JP3769584B2 - Substrate processing apparatus and method - Google Patents

Description

  The present invention relates to a method and apparatus for removing unnecessary materials such as an organic film coated on the outer periphery of the back surface of a base material such as a semiconductor wafer or a liquid crystal display substrate.

For example, as means for coating an insulating film, an organic resist, polyimide, or the like on a base material such as a semiconductor wafer or a glass substrate for liquid crystal display, methods such as coating by spin coating, CVD, and thin film deposition by PVD are known. However, in spin coating, the coated material is applied thicker to the outer periphery than the central portion of the substrate, and the outer periphery is raised. In addition, when plasma CVD is used as the CVD, for example, the electric field concentrates on the edge portion of the outer periphery of the base material and abnormal film growth occurs. Therefore, the film quality of the outer peripheral portion of the base material is different from that of the central portion. The thickness also tends to increase compared to the central part. In the case of thermal CVD using O ₃ , TEOS, etc., the resistance of the reactive gas is different between the central part of the substrate and the edge part of the outer periphery. The film thickness also increases.

  Further, in the manufacturing process of a semiconductor wafer, fluorocarbon deposited during anisotropic etching travels from the outer end surface of the wafer to the back surface and deposits there as well. For this reason, unnecessary organic substances adhere to the outer peripheral portion of the back surface of the wafer.

  Such a thin film on the outer periphery of the base material is likely to break when the base material is transported by a transport conveyor or housed in a transport cassette and transported, which may generate dust. Due to this dust, there is a problem that particles adhere to the wafer and the yield decreases.

Conventionally, a film formed by fluorocarbon wrapping around the wafer back surface during the anisotropic etching has been removed by, for example, passing O ₂ plasma from the front side surface of the wafer to the back surface by dry ashing. However, in the case of a low-k film, it is damaged when dry ashing is performed. For this reason, attempts have been made to process at low output. However, at low output, the fluorocarbon on the back surface of the wafer cannot be completely removed, and particles are generated when the substrate is transported, which is a main cause of lowering the yield.

As a prior document for processing the outer peripheral portion of a semiconductor wafer, for example, in Patent Document 1; Japanese Patent Laid-Open No. 5-82478, the central portion of the semiconductor wafer is covered with a pair of upper and lower holders, while the outer peripheral portion is projected. It is described that a plasma is sprayed. However, since the O-ring of the holder is in physical contact with the wafer, it is difficult to suppress the generation of particles.
Japanese Patent Application Laid-Open No. 8-279494 discloses that a central portion of a base material is placed on a stage and plasma is blown to the outer peripheral portion from above. Patent Document 3; Japanese Patent Laid-Open No. 10-189515 describes that plasma is blown from the lower side to the outer peripheral portion of a base material.

Japanese Patent Application Laid-Open No. 2003-264168 describes that ozone gas is sprayed from above while the outer periphery of a wafer is contact-heated from the back side by embedding a heater on the outer periphery of the stage.
Japanese Patent Application Laid-Open No. 2004-96086 describes that oxygen radicals are blown from above while the outer peripheral portion of a wafer is radiantly heated from the back side with an infrared lamp.
JP-A-5-82478 JP-A-8-279494 JP-A-10-189515 JP 2003-264168 A JP 2004-96086 A

  Heating is required to efficiently remove organic thin films such as photoresist and low-k film and deposited fluorocarbon during etching under normal pressure using a reactive gas such as ozone. That is, as shown in FIG. 33, the reaction is promoted and the etching rate (E / R) is increased when the portion to be processed is heated. However, if the entire wafer is exposed to a high temperature atmosphere, Cu oxidation, low-k characteristics, etc., such as changes in wiring and insulation film, will affect device characteristics and reliability. Will be reduced.

In Patent Document 4, the outer peripheral portion of the base material is heated by a heater, but the film on the outer peripheral portion of the front side surface is removed by heating from the back side and transferring the heat to the front side. Therefore, not only heat transfer loss occurs, but heat may be transferred to the inner part of the outer peripheral part, and the inner film may be altered. Moreover, since the outer peripheral part of the back surface of the base material is applied to the heater, the gas does not reach that much, and it is difficult to remove the film on the outer peripheral part of the back surface. In addition, particles may be generated by contact with the heater.
In Patent Document 5, the base material is radiantly heated from the back side with an infrared lamp, but by radiating infrared rays over a wide range, as in Patent Document 4, the inner part is also heated from the outer peripheral part, There is a possibility that the film there is altered.

  An object of this invention is to remove efficiently the unnecessary film | membrane of the back surface outer peripheral part of a base material, without affecting the film | membrane of a front side.

In order to achieve the above object, the present invention is an apparatus for removing unnecessary substances coated on the outer peripheral portion of the back surface of a substrate,
(A) a stage having a support surface for supporting the base material so that the outer peripheral portion protrudes;
(B) A light source disposed away from the processing target position on the outer peripheral portion of the back surface of the substrate supported by the stage, and a heat beam from the light source is directed to the processing position so as not to diverge. A radiant heater having an optical system;
(C) It has a blow-out port that blows out a reactive gas connected to a reactive gas supply source that supplies a reactive gas for removing unnecessary substances, and this blow-out port is located on the back side of the support surface or its extended surface or substantially Reactive gas supply means disposed on the extended surface close to the position to be processed;
It is provided with.
According to this characteristic configuration, it is possible to locally heat the outer peripheral portion of the back surface of the base material by locally applying a heat beam, and it is possible to spray a reactive gas to the locally heated portion from the vicinity thereof. As a result, it is possible to efficiently remove unnecessary materials at the site. On the other hand, it is possible to prevent or suppress even the part of the base material other than the local part from being heated. As a result, it is possible to prevent damage to the film on the front side surface of the base material, particularly the inner portion of the outer peripheral portion. Moreover, since non-contact heating by radiation can be performed, generation of particles can be prevented.

It is desirable that the optical system of the radiant heater includes an irradiation unit that converges and radiates heat rays from a light source toward the processing position. This makes it possible to reliably irradiate and heat the heat ray to the outer peripheral portion of the back surface of the base material, and to reliably prevent other parts of the base material from being heated.
As the optical member for convergence, a parabolic reflector, a convex lens, a cylindrical lens, or the like can be used. These may be combined. Further, it is desirable to incorporate a focus adjustment mechanism in the irradiation part of the radiant heater. The focal point may be exactly adjusted to the processing position, or may be slightly shifted. Thereby, the density of the radiant energy given to the outer peripheral part of the back surface of the substrate, and the heating temperature and the irradiation area (condensed diameter, spot diameter) can be adjusted to an appropriate size. As a result, the processing width can be adjusted. In addition, when the notch part or orientation flat part on the outer periphery of the substrate comes to the processing position, if the condensing diameter (irradiation area) of the radiant heater is increased, the edge of the notch part or orientation flat part Heat rays can be applied to the back side, and the film attached to the back side can also be removed from the notch and orientation flat part.

  The irradiation part of the radiant heater is preferably arranged on the back side of the support surface or its extended surface. Thereby, it is possible to irradiate the heat beam directly to the outer peripheral portion of the back surface of the substrate (without being incident and reflected from the front side), and the irradiation efficiency can be improved. Moreover, it is preferable that the said irradiation part is arrange | positioned away from the said to-be-processed position from the said blower outlet. This facilitates the layout of the irradiation part and the outlet formation member. In addition, since the outlet is arranged in the vicinity of the heated part from the light source, the reactive gas can be reliably blown to the treated part in a non-diffusion, high concentration, high activity, and unnecessary object can be removed. Efficiency can be reliably increased.

  A reflective member that totally reflects the heat beam from the light source to the processing position may be provided on the back side of the processing position and in the vicinity of the processing position. Accordingly, the light source can be arranged in the vicinity of the extended surface of the support surface or on the front side thereof.

  It is preferable that the irradiation part and the outlet of the radiant heater are arranged in different directions with respect to the processing position. This further facilitates the layout of the radiant heater and the outlet formation member.

  It is preferable that either one of the irradiation part and the outlet of the radiant heater is substantially disposed on a line passing through the processing position and orthogonal to the extension surface. The heating efficiency can be increased by substantially arranging the irradiation part of the radiant heater on the orthogonal line, and the reaction efficiency can be increased by substantially arranging the outlet on the orthogonal line.

The optical system of the radiant heater may include a waveguide optical transmission system extending from a light source to the processing position. Thereby, the heat ray from a light source can be reliably transmitted to the back surface outer peripheral part of a base material. An optical fiber is preferably used as the waveguide. This facilitates routing. The optical fiber is preferably a bundle of a plurality (many).
The waveguide may include a plurality of optical fibers, the optical fibers may be branched and extend from the light source, and distal ends thereof may be arranged apart from each other along the circumferential direction of the stage. Thereby, a heat ray can be simultaneously irradiated to several places of the peripheral direction of the outer peripheral part of a base material.

  It is preferable that an irradiation unit including the converging optical member is optically connected to a distal end portion of an optical transmission system such as the optical fiber.

The light source may be a point light source, a linear light source along the circumferential direction of the stage, or an annular light source along the entire circumference of the stage. In the case of a point light source, it is possible to locally heat one place on the outer peripheral portion of the back surface of the substrate. Note that the point light of the point light source may be converted into linear light along the outer periphery of the base material by a convex lens, a cylindrical lens, or the like. In the case of a linear light source, the range extending in the circumferential direction of the outer peripheral portion of the back surface of the substrate can be locally heated linearly. In the case of an annular light source, the entire outer periphery of the back surface of the substrate can be locally heated in an annular shape. A plurality of point light sources or linear light sources may be arranged along the circumferential direction of the stage.
Similarly, the shape of the outlet may be a dot (spot shape), a line along the circumferential direction of the stage, or an annular shape along the entire circumference of the stage. May be. The point light source may be a point (spot) outlet, the linear light source may be a linear outlet, and the annular light source may be an annular outlet.
A plurality of dotted outlets and linear outlets may be arranged along the circumferential direction of the stage. In this case, it is desirable to arrange the irradiation unit and the outlet as a set.

  It is desirable that the output wavelength of the radiant heater corresponds to the absorption wavelength of the unwanted material. As a result, energy can be efficiently applied to unnecessary materials, and heating efficiency can be increased. The light emission wavelength of the light source may correspond to the absorption wavelength of the unwanted material, or only the absorption wavelength may be extracted by a wavelength extraction means such as a band pass filter.

A laser light source, a lamp light source, or the like can be used as the light source. A laser light source is generally a point light source, has good light condensing properties, is suitable for convergent irradiation, can apply energy to an unnecessary object at a site to be processed at a high density, and is instantaneously heated to a high temperature. Can do. Control of the processing width is also easy. The type of laser may be an LD (semiconductor) laser, a YAG laser, an excimer laser, or other types. For example, the wavelength of the LD laser is 808 nm to 940 nm, the wavelength of the YAG laser is 1064 nm, and the wavelength of the excimer laser is 157 nm to 351 nm. The power density is preferably about 10 W / mm ² or more. The oscillation form may be CW (continuous wave) or a pulse wave. Desirably, it can be continuously processed by high-frequency switching. It is more preferable to use a light emission wavelength that matches the absorption wavelength of the unwanted material.

Examples of the lamp light source include a near infrared lamp such as a halogen lamp and an infrared lamp such as a far infrared lamp. The light emission form of the lamp light source is continuous light emission. The emission wavelength of the infrared lamp is, for example, 760 nm to 10000 nm, and 760 nm to 2000 nm is the near infrared band. It is preferable to extract and irradiate a wavelength that matches the absorption wavelength of the unwanted matter from the wavelength range using a wavelength extraction means such as the band-pass filter.
The radiant heater (particularly lamp light source type) is preferably cooled by a radiant heater cooling means such as a refrigerant or a fan.

It is desirable that the outlet forming member (nozzle) that forms the outlet of the reactive gas supply means is made of a light-transmitting material. Thereby, even if the optical path of the radiant heater interferes with the blowout port forming member, light can be reliably irradiated to the treated portion of the base material through the blowout port forming member, and the portion can be reliably heated. Can do. As a result, the blowout port forming member can be reliably arranged in the vicinity of the processing target part without being restricted by the optical path of the radiant heater, and the reactive gas can be reliably blown from the vicinity to the part to be processed. it can. The translucent material, e.g., quartz, acrylic, transparent Teflon (registered trademark, polytetrafluoroethylene) is used, a transparent resin such as transparent polyvinyl chloride or the like may. When a transparent resin having low heat resistance is used, it is desirable to adjust the output of the radiant heater or the like so as not to deform or dissolve.

  An enclosure surrounding the position to be processed is provided on the radially outer side of the stage, and a reactive gas blow-out port is disposed in the enclosure, while an irradiation unit of the radiant heater is provided outside the enclosure, and at least the enclosure You may comprise the site | part of the side which faces an irradiation part with a translucent material. Thus, the treated reactive gas can be reliably prevented from leaking to the outside, and the heat beam of the radiant heater can be transmitted through the enclosure, and the treated portion of the substrate can be reliably radiantly heated.

The blowing port forming member may be provided with a swirl flow forming portion that swirls the reactive gas in the circumferential direction of the blowing port. As a result, the reactive gas can be sprayed uniformly on the treated portion of the substrate.
The swirl flow forming portion has a plurality of swirl guide holes extending in a substantially tangential direction of the blowout port and connected to the inner peripheral surface of the blowout port and spaced apart from each other in the circumferential direction of the blowout port. It is desirable to constitute a path portion upstream of the outlet.

The component of the reactive gas is selected according to the unnecessary material to be removed. For example, when the unnecessary material to be removed is an organic film such as fluorocarbon, it is desirable to use an oxygen system such as ozone or O ₂ plasma. The plasma may be obtained by adding perfluorocarbon (PFC) to O ₂ . Further, a gas containing an acid such as hydrofluoric acid vapor may be used.

As a reactive gas supply source (reactive gas generating reactor) of the reactive gas supply means, for example, an atmospheric pressure plasma processing apparatus can be used. When the reactive gas is ozone, an ozonizer may be used. When the reactive gas is hydrofluoric acid vapor, a hydrofluoric acid vaporizer or an injector may be used.
An atmospheric pressure plasma processing apparatus forms a glow discharge between electrodes under a substantially normal pressure (pressure near atmospheric pressure), and converts a process gas into a plasma (including radicalization and ionization) into a reactive gas. is there. In addition, “substantially normal pressure” in the present invention refers to a range of 1.013 × 10 ^{4 to} 50.663 × 10 ⁴ Pa, and considering the ease of pressure adjustment and the simplification of the apparatus configuration, 1.333 × 10 ^{4 to} 10.664 × 10 ⁴ Pa, and more preferably 9.331 × 10 ^{4 to} 10.9797 × 10 ⁴ Pa.

The reactive gas supply source may be disposed near the processing position, or may be disposed apart from the reactive gas supply source and led to the vicinity of the processing position by the blowing path forming member.
The outlet passage from one reactive gas supply source may be branched and connected to a plurality of outlets.

  When the reactive gas supply means has a blow-off path forming member that forms a blow-out path that guides the reactive gas from the reactive gas supply source to the blow-out port, the blow-out path forming member is a blow-off path. It is desirable that the temperature is controlled by the temperature control means. As a result, the temperature of the reactive gas passing through the blowing channel can be controlled and maintained at an appropriate temperature, and the activity can be maintained. For example, when ozone is used as the reactive gas, the lifetime of oxygen radicals can be extended by cooling and maintaining at about 25 ° C. As a result, a reaction with an unnecessary substance can be ensured, and the removal processing efficiency can be improved.

  The blowout path temperature control means can be constituted by, for example, a temperature control path through which a temperature control medium passes or a fan. The blowout path forming member may have a double pipe structure, the inner path thereof may be used as a blowout path, for example, and a reactive gas may be allowed to flow therethrough, and the outer annular path may be used as a temperature control path and a temperature control medium may be passed therethrough. As the temperature control medium, water, air, helium, chlorofluorocarbon, or the like can be used.

  The stage is preferably provided with a heat absorption means for absorbing heat from the support surface. Thereby, even if the heat of a back surface outer periphery part is transmitted to parts other than the back surface outer periphery part which should be heated of a base material, especially an inner side part from an outer peripheral part, this can be absorbed with a heat absorption means. Therefore, it is possible to reliably prevent damage to the film on the inner side of the outer peripheral portion of the front side surface other than the unnecessary film on the outer peripheral portion of the back surface to be removed.

  For example, the heat absorbing means cools the stage with a refrigerant. As the specific structure, for example, the inside of the stage forms a cavity and a refrigerant chamber is configured, and the refrigerant is fed into the refrigerant chamber for filling, circulation, or circulation. By increasing the internal volume of the refrigerant chamber, the heat capacity and thus the heat absorption capacity can be sufficiently increased. For example, a fluid such as water, air, or helium is used as the refrigerant. The refrigerant may be compressed and supplied to the refrigerant chamber vigorously. Thereby, it can be made to flow evenly to every corner of the refrigerant chamber, and the heat absorption efficiency can be improved. In addition, even if the momentum of the refrigerant supply is moderate or the supply and discharge of the exhaust gas is stopped, heat absorption can be secured by natural convection in the refrigerant chamber.

Further, as a heat absorption means by the refrigerant, a refrigerant path may be formed by a pipe or the like inside or on the back surface of the stage, and the refrigerant may be passed therethrough.
As the heat absorption means, for example, a Peltier element may be used, and the heat absorption side may be embedded near the support surface with the heat absorption side facing the support surface.
The heat absorbing means may be provided at least at the outer peripheral portion of the stage, and may not be provided at the central portion.

The reactive gas supply means has a blow-off path forming member that forms a blow-out path that leads the reactive gas from the reactive gas supply source to the blow-out port, and the blow-out path forming member is along the stage, It may be cooled by the heat absorption means. As a result, there is no need to provide a cooling means dedicated to the blowout path, the configuration can be simplified, and the cost can be reduced.
This structure is particularly effective when the reactive gas is to be cooled, for example, when ozone is used as the reactive gas.

It is preferable that an electrostatic chuck or a vacuum chuck mechanism is incorporated in the stage as a fixing means for the substrate placed on the support surface. The suction chuck mechanism may be provided over the entire support surface of the stage, or may be provided only in the outer peripheral region of the support surface and not in the central region. If it is provided only in the outer peripheral region, particles caused by adsorption can be reduced.
It is desirable that the stage, the light source and the outlet are relatively moved.
Preferably, the stage is a circular stage, and the circular stage rotates relative to the light source and the outlet around a central axis. Thereby, even if a light source is a spot shape, an unnecessary object removal process can be performed along the circumferential direction of the back surface outer peripheral part of a base material. Even when the light source is ring-shaped, the processing uniformity can be improved by executing the relative rotation. The relative rotational speed (relative movement speed) is appropriately set according to the temperature at which the outer peripheral portion of the back surface of the substrate is to be heated.

It is desirable to provide a frame that surrounds the stage and thus the processing position in the circumferential direction and forms an annular space with the stage. As a result, the treated reactive gas can be kept near the position to be treated for a while, and diffusion to the outside can be suppressed, and a sufficient reaction time can be secured. It is desirable that the light source and the air outlet are housed in or face the annular space and fixed to the frame.
Furthermore, it is desirable to provide a rotational drive mechanism for rotating the stage relative to the frame around a central axis. The stage may be rotated while the frame is fixed, and the frame may be rotated while the stage is fixed.
Furthermore, it is desirable to provide a labyrinth seal that seals between the back side opposite to the support surface side (front side) of the stage and the frame while allowing relative rotation. Accordingly, the stage or the frame can be rotated without any trouble, and the processed reactive gas can be prevented from leaking from between the back side of the stage and the frame.

  A cover member that extends toward the stage side and covers the front side of the processing position on the front side portion of the frame, and covers the annular space alone or in cooperation with the outer peripheral portion of the base placed on the stage It is desirable to provide. Thereby, it is possible to prevent the treated reactive gas from leaking out from the annular space to the front side.

  The cover member is preferably retractable from a position covering the annular space. Thus, when the substrate is set on or taken out of the stage, the cover member can be retracted to prevent the cover member from interfering with the setting / removing operation.

It is desirable that an annular space suction means for sucking the annular space is connected to the annular space. Thereby, the processed reactive gas can be sucked and exhausted from the annular space.
It is desirable to provide suction means for sucking the vicinity of the outlet. Thereby, the processed reactive gas can be quickly sucked and exhausted from the periphery of the site to be processed on the outer peripheral portion of the back surface of the base material.

  It is desirable to form a step on the outer peripheral portion of the support surface of the stage in cooperation with the outer peripheral portion of the base material to form a gas reservoir. As a result, the reactive gas blown out from the outlet can be temporarily retained in the gas reservoir, the time for contacting the outer periphery of the back surface of the substrate can be lengthened, the reaction time can be sufficiently secured, and the reaction efficiency can be increased. Can be increased.

  It is desirable to dispose an inert gas spraying member that sprays an inert gas directly in the center of the support surface. As a result, the reactive gas can be prevented from flowing to the front side surface of the base material, and damage to the front side film can be reliably prevented. The inert gas blowing member may be a nozzle or a fan filter unit. Of course, the inert gas blowing member is arranged at least as much as the thickness of the substrate from the support surface. In addition, the base material is retracted so as not to get in the way during the installation / removal operation of the base material. As the inert gas, pure nitrogen gas, clean dry air (CDA), or the like can be used.

The substrate processing apparatus preferably includes an exhaust nozzle having a suction port and suction means for sucking the exhaust nozzle.
It is preferable that the suction port of the exhaust nozzle is disposed so as to face the blowout port across the processing position.
It is preferable that the blow-out port and the suction port are arranged to face each other with the position to be processed along the tangential direction of the outer peripheral portion of the base material.
It is preferable that the blowout port is disposed on the upstream side and the suction port is disposed on the downstream side along the forward direction of the rotation direction of the substrate.

It is preferable that the suction port is larger than the blowout port.
It is preferable that the suction port has a diameter 2 to 5 times that of the blowout port.
The inner diameter of the outlet is preferably about 1 to 3 mm, for example. On the other hand, the inner diameter of the suction port is preferably about 2 to 15 mm, for example.
Thereby, it is possible to suppress the diffusion of the processed gas and the reaction by-product, and the gas can be reliably sucked into the suction port and exhausted.

  In addition, the present invention is a method for removing unnecessary materials coated on the outer peripheral portion of the back surface of the base material, and the base material is supported on the stage so that the outer peripheral portion of the base material protrudes, and from the radiant heater. Reactive gas supply means that radiates heat rays to focus on the outer peripheral portion of the back surface of the base material or the vicinity thereof and locally heats, and in the vicinity of the locally heated portion, heads to the portion. A reactive gas for removing unnecessary substances is blown out from the outlet. As a result, the unnecessary film on the outer peripheral portion of the back surface of the substrate can be efficiently removed without affecting the film on the front side, as in the above-described apparatus invention.

  According to this invention, the back surface outer peripheral part of a base material can be heated locally, and reactive gas can be sprayed from the vicinity to this locally heated site | part. As a result, it is possible to efficiently remove unnecessary materials at the site. On the other hand, it is possible to prevent or suppress even the part of the base material other than the local part from being heated. As a result, it is possible to prevent damage to the film on the front side surface of the base material, particularly the inner portion of the outer peripheral portion.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 3 show a first embodiment of the present invention. First, the substrate 90 to be processed will be described. As shown in phantom lines in FIGS. 1 and 2, the base material 90 is, for example, a semiconductor wafer and has a circular thin plate shape. As shown in FIG. 3, a film 92 made of, for example, a photoresist is coated on the upper surface, that is, the front side surface of the wafer 90. The absorption wavelength of the photoresist is 1500 nm to 2000 nm. The film 92 not only covers the entire upper surface of the wafer 90 but also reaches the outer peripheral portion of the back surface through the outer end surface. In the substrate processing apparatus of the present invention, the outer peripheral portion of the back surface of the wafer 90 is a site to be processed, and the film 92c is removed as an unnecessary material.

  As shown in FIGS. 1 and 2, the substrate processing apparatus includes a frame 50, a stage 10 as a substrate support means for supporting a wafer 90, a laser heater 20 as a radiant heater, and a reactive gas supply. And a plasma nozzle head 30 as means.

  The frame 50 includes a perforated disk-shaped bottom plate 51 and a cylindrical peripheral wall 52 that protrudes upward from the outer periphery of the bottom plate 51, has an L-shaped annular shape, and is fixed to a gantry (not shown). .

  The stage 10 is disposed inside the frame 50 so as to be surrounded by the frame 50. The stage 10 is concentric with the frame 50 and has a circular shape in plan view having a smaller diameter than the peripheral wall 52, and the peripheral side surface has a taper shape with a diameter decreasing downward. The stage 10 is connected to a rotation drive mechanism (not shown) and is rotated around the central axis 11. In addition, while fixing the stage 10, a rotation drive mechanism may be connected to the flame | frame 50, and this flame | frame 50 may be rotated.

A wafer 90 to be processed is placed horizontally on the upper surface 10a (support surface, front side surface) of the stage 10 with its center aligned.
The diameter of the upper surface of the stage 10, that is, the support surface 10 a that supports the wafer 90 is slightly smaller than the diameter of the circular wafer 90. Therefore, when the wafer 90 is placed on the stage 10, the entire outer periphery of the wafer 90 projects slightly outward in the radial direction from the stage 10. The protruding amount is, for example, 3 to 5 mm. As a result, the back surface of the wafer 90 is exposed (opened) over the entire periphery of the narrow outer periphery, while most of the back surface excluding the inner portion, that is, the narrow outer periphery, is in contact with the upper surface of the stage 10. Covered.
Although not shown, the stage 10 incorporates a vacuum or electrostatic chuck chuck mechanism. With this suction chuck mechanism, the wafer 90 is sucked and fixed to the support surface 10 a of the stage 10. The suction chuck mechanism may be provided over the entire upper surface of the stage 10, or may be provided only in the outer peripheral portion of the stage 10 (the portion immediately inside the outer peripheral protruding portion of the wafer 90) and not in the central portion. . If the suction chuck mechanism is provided only on the outer peripheral portion of the stage 10, particles caused by suction can be reduced.

  A rear surface outer peripheral portion of the wafer 90 placed on the stage 10, that is, a position where a processing target portion exists is a processing position P. The processing position P is located on a virtual surface (extended surface) obtained by extending the upper surface 10a of the stage 10 radially outward.

  As the material of the stage 10, for example, aluminum is used because it has good thermal conductivity and does not cause metal contamination. In order to ensure corrosion resistance against the reactive gas, an alumina layer by anodization may be provided on the surface, and a fluorine resin such as PTFE may be infiltrated.

The inside of the stage 10 is a cavity, which is a refrigerant chamber 41 (heat absorption means). The refrigerant chamber 41 has a sufficient internal volume. A refrigerant supply path 42 and a refrigerant discharge path 43 are connected to the refrigerant chamber 41. These paths 42 and 43 extend from the stage 10 through the center shaft 11. The upstream end of the refrigerant supply path 42 is connected to a refrigerant supply source (not shown). The refrigerant supply source supplies, for example, water as a refrigerant to the refrigerant chamber 41 via the refrigerant supply path 42. Thereby, the refrigerant chamber 41 is filled with water. The water temperature may be room temperature. Further, the refrigerant is appropriately discharged from the refrigerant discharge path 43 and newly supplied from the refrigerant supply path 42. The discharged refrigerant may be circulated by returning to the refrigerant supply source and recooling.
As the refrigerant, air, helium, or the like may be used instead of water. The compressed fluid may be sent to the refrigerant chamber 41 with momentum and flowed inside the refrigerant chamber 41.
A Peltier element may be embedded in the stage 10 as a heat absorbing means.
The heat absorbing means may be provided at least at the outer peripheral portion of the stage 10 (the portion immediately inside the outer peripheral protruding portion of the wafer 90), and may not be provided at the central portion.

The stage 10 is located above the bottom plate 51 of the frame 50 and at a substantially intermediate height of the peripheral wall 52, and has a larger diameter than the inner periphery of the bottom plate 51. ) Inward in the radial direction, the inner edge of the bottom plate 51 enters. A labyrinth seal 60 is provided between the lower surface of the stage 10 and the inner edge of the bottom plate 51. The labyrinth seal 60 has a pair of upper and lower labyrinth rings 61 and 62. The upper labyrinth ring 61 has a plurality of drooping pieces 61 a concentric with the stage 10 and fixed to the lower surface of the stage 10. The lower labyrinth ring 62 has a plurality of projecting pieces 62 a forming a multiple ring concentric with the frame 50 and the stage 10, and is fixed to the upper surface of the bottom plate 51 of the frame 50. The hanging pieces 61a and the protruding pieces 62a of the upper and lower labyrinth rings 61 and 62 are alternately meshed with each other.
An annular space 50 a is defined between the frame 50, the stage 10, and the labyrinth seal 60.

  A suction path 51 c extending from the valley of the labyrinth ring 62 is formed in the bottom plate 51 of the frame 50. The suction path 51c is connected to a suction / exhaust device (not shown) including a vacuum pump, an exhaust processing system, and the like via a pipe. The suction path 51c, the piping, and the suction / exhaust device constitute “a suction means for the annular space”.

An irradiation unit 22 (irradiation unit) of the laser heater 20 is attached to a portion on the radially outer side of the labyrinth ring 62 of the bottom plate 51 of the frame 50 so as to be separated below the outer peripheral edge of the stage 10.
The laser heater 20 includes a laser light source 21 that is a point light source, and the irradiation unit 22 that is optically connected to the laser light source 21 via an optical transmission system 23 such as an optical fiber cable. For example, an LD (semiconductor) laser light source is used as the laser light source 21 and emits a laser (heat beam) having an emission wavelength of 808 nm to 940 nm. The emission wavelength may be set in a range corresponding to the absorption wavelength of the photoresist film 92 coated on the substrate 90.
The laser light source 21 is not limited to the LD, and various types such as YAG and excimer may be used. If possible, a laser beam having a wavelength after visible light which is easily absorbed by the film 92 is used, and a laser beam having a wavelength matching the absorption wavelength of the film 92 is preferably used.
The light source 21 may be accommodated in the unit 22 and the optical transmission system 23 such as an optical fiber may be omitted.

  The laser irradiation unit 22 is considerably farther from the processing position P than the plasma nozzle head 30. As shown in FIG. 2, a plurality (three in the figure) of laser irradiation units 22 are provided at equal intervals in the circumferential direction of the frame 50 and the stage 10. As shown in FIG. 1, the laser irradiation unit 22 is disposed on a line L1 that passes through the processing position P and is orthogonal to the extended surface. The laser irradiation direction of the laser irradiation unit 22 is directed right above the line L1 and is orthogonal to (intersects) the processing position P, that is, the outer periphery of the wafer 90 placed on the stage 10. .

The laser irradiation unit 22 accommodates optical members such as a convex lens and a cylindrical lens. As shown in FIG. 3, the laser L sent from the light source 21 is placed on the processing position P, that is, the stage 10. The wafer 90 is converged toward the outer periphery of the back surface. Further, the laser irradiation unit 22 has a built-in focus adjustment mechanism. The focus adjustment mechanism not only allows the laser focus to be adjusted to the processing position P, but also slightly shifts up and down with respect to the processing position P. You can also.
The optical transmission system 23 and the irradiation unit 22 constitute an “optical system” that transmits the thermal light source from the light source 21 so as not to diverge to the vicinity of the processing position and converges and irradiates the processing position.

  As shown in FIG. 1, the plasma nozzle head 30 is attached to the peripheral wall 52 of the frame 50. The plasma nozzle head 30 is disposed on the radially outer side of the stage 10 with respect to the processing position P, and is disposed in a direction different from the laser irradiation unit 22 with respect to the processing position P. As shown in FIG. 2, the plasma nozzle heads 30 are provided in the circumferential direction of the stage 10 at equal intervals and the same number (three in the drawing) as the laser irradiation units 22, and the same circumference as the laser irradiation units 22. A pair is arranged at a position slightly downstream of the laser irradiation unit 22 in the wafer rotation direction.

  The plasma nozzle head 30 has a stepped columnar shape that tapers stepwise, and is arranged with its axis lined horizontally along the radial direction of the stage 10. As shown in FIG. 1, the plasma nozzle head 30 accommodates a pair of electrodes 31 and 32. These electrodes 31 and 32 form a double ring shape, and a normal pressure space 30a is formed between them. A solid dielectric is coated on the opposing surface of at least one of the electrodes 31 and 32.

  A power source (electric field applying means) (not shown) is connected to the inner electrode 31, and the outer electrode 32 is grounded. The power supply is configured to output, for example, a pulsed voltage to the electrode 31. It is desirable that the rise time and / or fall time of this pulse is 10 μs or less, the electric field strength in the interelectrode space 30a is 10 to 1000 kV / cm, and the frequency is 0.5 kHz or more. Instead of the pulse voltage, a continuous wave voltage such as a sine wave may be output.

  A process gas supply source (not shown) is connected to a base end portion (upstream end) facing the side opposite to the stage 10 side of the interelectrode space 30a. The process gas supply source stores, for example, oxygen or the like as the process gas, and supplies it to the interelectrode space 30a in an appropriate amount.

  As best shown in FIG. 3, a resin blowout port forming member 33 having a disk shape is provided at the tip of the plasma nozzle head 30 facing the stage 10 side. An outlet 30 b is formed at the center of the outlet forming member 33. The outlet 30b is connected to the downstream end of the inter-electrode space 30a facing the stage 10 side, and the axis line is horizontally oriented along the radial direction of the stage 10 so as to be on or slightly below the extended surface of the upper surface 10a of the stage 10. And is opened at the tip of the plasma nozzle head 30. The tip of the plasma nozzle 30 and thus the outlet 30b are arranged in the vicinity of the processing position P, and when the wafer 90 is placed on the stage 10, it is very close to the outer edge. A reactive gas G obtained by converting the process gas into a plasma is injected along the axis of the outlet 30b. This injection direction is orthogonal to (or forms an angle from) the irradiation direction of the laser L of the laser heater 20. The intersection between the injection direction and the irradiation direction is substantially located on the back surface of the protruding outer peripheral portion of the wafer 90 on the stage 10.

A suction port 30 c is formed on the front end surface of the plasma nozzle head 30 between the front end surface forming member 34 and the blowout port forming member 33. The suction port 30c has an annular shape so as to be close to and surround the blowout port 30b. As shown in FIG. 1, the suction port 30 c is connected to a suction exhaust device (not shown) via a suction path 30 d formed in the plasma nozzle head 30. The suction port 30c, the suction path 30d, and the suction / exhaust device constitute “suction means in the vicinity of the blowout port” or “suction means in the annular space”.
The plasma nozzle head 30, the power source, the process gas supply source, the suction exhaust device, and the like constitute an atmospheric pressure plasma processing apparatus.

A method of removing the film 92c on the outer peripheral portion of the back surface of the wafer 90 by the substrate processing apparatus having the above configuration will be described.
The wafer 90 to be processed is placed on the upper surface of the stage 10 by a transfer robot or the like so as to be centered and chucked. The outer peripheral portion of the wafer 90 protrudes outward in the radial direction of the stage 10 over the entire periphery. The laser beam L is emitted from the laser irradiation unit 22 of the laser heater 20 while focusing on the rear surface of the protruding outer peripheral portion of the wafer 90, that is, the processing position P. Thus, the film 92c on the outer peripheral portion of the back surface of the wafer 90 can be radiantly heated in a spot shape (locally). Since it is point condensing, laser energy can be applied to the irradiated portion with high density. If the wavelength of the laser corresponds to the absorption wavelength of the film 92c, the absorption efficiency of the laser energy can be further increased. Thereby, the spot-like irradiated portion of the film 92c can be instantaneously heated to several hundred degrees (for example, 600 ° C.). The focal position is slightly shifted above and below the processing position P by the focus adjustment mechanism of the laser irradiation unit 22, so that the condensed diameter on the outer periphery of the back surface of the wafer 90, the area of the heated portion, the density of the radiant energy, and the The heating temperature of the heating part can be adjusted. As a result, the processing width can be adjusted. In addition, in the notch part and the orientation flat part, the laser can be applied to the edge of the notch part and orientation flat part by increasing the condensing diameter, and as a result, the film on the back side of the edge of the notch part and orientation flat part. Can be reliably removed.
Since it is radiant heating, it is not necessary to bring the heated portion of the wafer 90 into contact with the heating source, and no particles are generated.
On the other hand, even if heat is transmitted radially inward from the heated portion of the wafer 90, the heat can be absorbed by the water filled in the refrigerant chamber 41 in the stage 10. As a result, the temperature rise in the portion inside the heated portion of the wafer 90 can be suppressed. Therefore, not only the alteration of the film 92 can be suppressed, but also the reaction with the film 92 can be suppressed even if ozone of the reactive gas flows into the center of the upper surface of the wafer 90. As a result, the film 92 can be prevented from being damaged and can be reliably maintained in good quality.

  In parallel, a process gas (oxygen or the like) is supplied from a process gas supply source to the interelectrode space 30 a of the plasma nozzle head 30. Further, a pulse voltage is supplied from the pulse power source to the electrode 31, and a pulse electric field is applied to the interelectrode space 30a. Thereby, an atmospheric pressure glow discharge plasma is formed in the interelectrode space 30a, and a reactive gas such as ozone is formed from a process gas such as oxygen. This reactive gas is blown out from the blow-out port 30b, and is blown onto the locally heated portion on the back surface of the wafer 90 to cause a reaction. Thereby, the film 92c at this portion can be etched and removed. Since this part is sufficiently heated locally, the etching rate can be sufficiently increased.

Furthermore, the gas around the portion where the etching process is performed can be sucked into the suction port 30c by the suction means and exhausted through the suction passage 30d. As a result, the reactive gas that has been processed and the by-products generated by the etching can be quickly removed from the periphery of the site where the etching process is being performed, thereby increasing the etching rate. Further, gas inflow to the front side surface of the wafer 90 can be prevented, and damage to the film 92 on the front side surface can be more reliably prevented.
Further, by the suction means, the processed reactive gas or the like can be guided from the periphery of the outer peripheral portion of the wafer 90 toward the labyrinth seal 60 and can be sucked and exhausted from the gap of the labyrinth seal 60. Outflow of reactive gas or the like from the labyrinth seal 60 to the inside in the radial direction can be reliably prevented.

In parallel with the above operation, the stage 10 is rotated by the rotation drive mechanism. As a result, the removal range of the film 92c on the outer peripheral portion of the back surface of the wafer 90 can be extended in the circumferential direction. As a result, the film 92c on the outer peripheral portion of the back surface can be removed over the entire circumference.
By using the labyrinth seal 60 as a seal between the stage 10 and the frame 50, the stage 10 can be smoothly rotated without friction with the frame 50.

FIG. 4 uses the same apparatus as FIG. 1 and projects the outer edge of the wafer 3 mm from the stage 10, and the water temperature in the refrigerant chamber 41 is 50 ° C., 23.5 ° C., 5.2 ° C. In each of the cases, the experimental results of measuring the surface temperature of the wafer with respect to the distance from the vicinity of the heated portion of the outer edge of the wafer to the radially inward direction are shown. The output conditions of the laser heater 20 are as follows.
Laser emission wavelength: 808 nm
Output: 30W
Local heating area diameter: 0.6mm
Output density: 100 w / mm ²
Oscillation mode: continuous wave As shown in FIG. 4, when the water temperature is 23.5 ° C., which is normal temperature, the temperature is about 110 ° C. due to heat conduction from the heated portion in the vicinity of the heated portion on the outer edge of the wafer (heated The temperature is 600 ° C. or more at the portion, and the temperature is lowered to about 50 ° C. at the inner portion in the radial direction only 3 mm from there, and the central portion inside the radial direction is kept at 50 ° C. or lower. It was confirmed that even if it flows into the central portion of the front side surface, the reaction hardly occurs and damage to the film 92 can be suppressed.

Also, using the same apparatus as in FIG. 1, the outer edge of the wafer is projected 3 mm from the stage 10 and the laser output is set to 80 W and 100 W, in the vicinity of the heated portion of the outer edge of the wafer. The surface temperature of the wafer with respect to the distance in the radial inner direction was measured by thermography. Other conditions are as follows.
Wafer diameter: 300mm
Local heating area diameter: 1mm
Stage rotation speed: 3rpm
Water temperature in the stage refrigerant chamber: 23.5 ° C
As a result, as shown in FIG. 5, the surface temperature in the vicinity of the heated portion on the outer edge of the wafer was around 300 ° C. (about 700 to 800 ° C. at the heated portion), but from there, it went inward in the radial direction. As a result, the wafer temperature dropped rapidly, and the temperature was slightly below 100 ° C. at the inner part in the diameter direction of only 3 mm. Thereby, it was confirmed that damage to the film at the center of the wafer can be suppressed.

Next, another embodiment of the present invention will be described. In the following embodiments, the same reference numerals are given to the configurations corresponding to the above-described embodiments, and description thereof will be omitted as appropriate.
In the substrate processing apparatus shown in FIG. 6, the plasma nozzle head 30 is fixed to the bottom plate 51 of the frame 50 so as to be separated from the site to be processed and aligned with the laser irradiation unit 22 of the laser heater 20. The front end surface of the plasma nozzle head 30 is directed right above. A reactive gas passage 52 b extending from the tip opening 30 b ′ of the plasma nozzle head 30 is formed in the peripheral wall 52 of the frame 50. The tip of the reactive gas passage 52b reaches the inner peripheral surface of the peripheral wall 52, and a small cylindrical blowout nozzle 36 is connected to the inner peripheral surface. In the apparatus of FIG. 6, the blow nozzle 36 constitutes a blow port forming member, and the inside thereof forms a blow port 36a. The blowout nozzle 36 is made of a transparent and translucent material, such as tetrafluoroethylene-purple oloalkyl vinyl ether copolymer (PFA).

The blow-out nozzle 36 extends obliquely upward so as to protrude from the inner periphery of the peripheral wall 52, and its tip end portion is very close to the processing position P, that is, the back side of the protruding outer peripheral portion of the wafer 90 placed on the stage 10. It has become. Thereby, the blowing direction from the blowing nozzle 36 intersects the irradiation direction of the laser heater 20 facing vertically upward on the back surface of the protruding outer peripheral portion of the wafer 90 at an acute angle. (The radiant heater and the air outlet are arranged in different directions (directions forming an acute angle) with respect to the processing position P on the back side of the extended surface of the support surface 10a.)
The frame 50 having the reactive gas passage 52 b and the blowout nozzle 36 are components of the “reactive gas supply means” together with the plasma nozzle head 30.

According to this configuration, since the blowing nozzle 36 is disposed in the very vicinity of the portion to be processed of the wafer 90, a high concentration of reactive gas such as ozone blown from the nozzle 90 is not diffused while being highly active. In particular, the site to be processed can be reliably reached, the reaction efficiency with the film 92c can be improved, and the etching rate can be increased. Further, since the blowing direction of the reactive gas is not parallel to the back surface of the wafer 90 but is angled, the reaction efficiency with the film 92c can be further improved, and the etching rate can be further increased.
On the other hand, the blowing nozzle 36 is disposed so as to enter the optical path of the laser L from the laser heater 20, but the blowing nozzle 36 does not block the laser L because it has translucency. . Therefore, the part to be processed can be reliably heated, and a high etching rate can be secured.
Note that the blowing nozzle 36 may be disposed off the optical path of the laser L. In that case, the blowing nozzle 36 need not be made of a permeable material, and for example, stainless steel or the like may be used. However, in consideration of the possibility of a high temperature due to laser reflection and a decrease in ozone concentration due to a thermal reaction, it is preferable to use Teflon (registered trademark) or the like that has low radiation heat absorbability and high ozone resistance.

In FIG. 6, a step is formed on the upper surface of the peripheral wall 52 of the base plate, and an annular upper peripheral wall 53 having an inverted L-shaped cross section is covered with the step. The inner end edge of the upper peripheral wall 53 is disposed in the vicinity of the blowout nozzle 36, and in the vicinity of the outer end edge of the wafer 90 on the stage 10. An annular groove 53c (suction port) is formed at the inner end edge of the upper peripheral wall 53 so as to open toward the inner end edge and over the entire circumference in the circumferential direction. A suction path 53d extends from the groove bottom of the annular groove 53c at the same circumferential position as the blowing nozzle 36 to the outer periphery of the upper peripheral wall 53 and is connected to the suction connector 57, and is further connected to a suction exhaust device (not shown). . Thereby, the processed reactive gas can be sucked and exhausted from the periphery of the outer peripheral portion of the wafer 90.
The groove 53c, the suction path 53d, and the suction / exhaust device constitute “suction means in the vicinity of the outlet” or “suction means in the annular space”.

  In the substrate processing apparatus shown in FIG. 7, the structure of the plasma nozzle head is different from that already described. That is, the plasma nozzle head 30X of FIG. 7 has an annular shape corresponding to the stage 10 or the frame 50, and is arranged on the upper side of the stage 10 and the frame 50 so as to be concentric with them. The plasma nozzle head 30X has a retracted position (this state is not shown) that is largely separated above the stage 10 and the frame 50 by a lifting mechanism (not shown), and a set position (this state is shown on the peripheral wall 52 of the frame 50). 7). After the plasma nozzle head 30X is raised to the retracted position, the wafer 90 is placed on the stage 10, and then the plasma nozzle head 30X is lowered to the set position to perform processing.

  Inside the plasma nozzle head 30X, electrodes 31X and 32X having a double annular shape are accommodated over the entire circumference. A pulse power supply (not shown) is connected to the inner electrode 31X, and the outer electrode 32X is grounded. A narrow space 30ax that forms an annular shape over the entire circumference of the plasma nozzle head 30X is formed by the opposing surfaces of the electrodes 31X and 32X. A process gas such as oxygen from a process gas supply source (not shown) is introduced uniformly over the entire circumference in the circumferential direction of the upper end (upstream end) of the interelectrode space 30ax, and is caused by atmospheric pressure glow discharge in the interelectrode space 30ax. It is turned into plasma and reactive gas such as ozone is generated. Similar to the plasma nozzle head 30 described above, the solid dielectric layer is coated on at least one of the opposing surfaces of the electrodes 31X and 32X.

  At the bottom of the plasma nozzle head 30X, a reactive gas path 30bx 'extending obliquely from the lower end (downstream end) of the interelectrode space 30ax is formed. On the other hand, a reactive gas passage 52b extending vertically is also formed in the peripheral wall 52 of the frame 50. When the plasma nozzle head 30X is set to the set position, both reactive gas passages 30bx ′ and 52b are continuous. .

  A base end portion of a blowout nozzle 36 made of a translucent material is connected to a lower end portion (downstream end) of the reactive gas passage 52b of the frame 50. The blowout nozzle 36 is embedded in the peripheral wall 52 so as to be horizontal along the radial direction of the frame 50, and a tip end portion projects from the inner end surface of the peripheral wall 52. As a result, the processing position P, that is, the position near the back side of the outer peripheral portion of the wafer 90 placed on the stage 10 is set. The blowout nozzles 36 are arranged in the same number as the laser irradiation units 22 apart from each other in the circumferential direction so as to correspond one-to-one to the same circumferential position as the laser irradiation unit 22 of the laser heater 20. As a result, the reactive gas generated in the interelectrode space 30ax is blown from the blowing nozzle 36 through the reactive gas passages 30bx ′ and 52b and hits the portion of the film 92c locally heated by the laser heater 20. It is designed to be removed by etching. Even if the optical path of the laser L and the blowout nozzle 36 interfere with each other, the blowout nozzle 36 has translucency as in the embodiment of FIG.

A cover ring 37 is provided at the radially inner portion of the bottom of the plasma nozzle head 30X. When the plasma nozzle head 30X is in the set position, a suction port 30cx is formed between the outer end surface of the cover ring 37 that is tapered and the upper portion of the inner peripheral surface of the peripheral wall 52 of the frame 50. It has become. The suction port 30 cx is located just above the outer edge of the wafer 90 on the stage 10. The suction port 30cx is connected to a suction / exhaust device (not shown) through a suction passage 30dx and the like connected to the back thereof. Thereby, the processed reactive gas can be sucked and exhausted from the periphery of the outer peripheral portion of the wafer 90.
The suction port 30cx, the suction path 30dx, and the suction / exhaust device constitute “suction means in the vicinity of the outlet” or “suction means in the annular space”.
The cover ring 37 constitutes a suction port forming member.

  The substrate processing apparatus shown in FIG. 8 is a combination of the entire substrate processing apparatus of FIG. 6 and the annular plasma nozzle head 30X of FIG. Therefore, in the apparatus of FIG. 8, two types of plasma nozzle heads 30 and 30X are provided on the lower side and the upper side. The lower plasma nozzle head 30 is for removing the film 92c on the outer peripheral portion of the back surface of the wafer 90, as in the above-described embodiment. On the other hand, the upper plasma nozzle head 30X is for removing the outer peripheral portion of the front side surface of the wafer 90 and the film 92 (see FIG. 3) on the outer end surface. Therefore, unlike the one shown in FIG. 7, the bottom of the plasma nozzle head 30 </ b> X of the substrate processing apparatus of FIG. 8 is formed with a blowout port 30 bx that extends straight down from the interelectrode space 30 ax and opens to the bottom surface. . The outlet 30bx has an annular shape extending over the entire circumference in the circumferential direction of the plasma nozzle head 30X. When the plasma nozzle head 30X is set to the set position, the outlet 30bx is arranged just above the outer peripheral portion of the base material on the stage 10. The reactive gas from the inter-electrode space 30ax is blown straight down from the blow-out port 30bx, blown to the outer peripheral portion of the front side surface of the wafer 90, and part of the reactive gas goes around the outer end surface of the wafer 90. Thus, the outer peripheral portion of the front side surface of the wafer 90 and the film 92 on the outer end surface can also be etched and removed. Since the blowout port 30bx forms an annular shape and extends over the entire circumference of the wafer 90, the reactive gas can be sprayed to the entire circumference of the wafer 90 at once, and etching can be performed efficiently. Further, the process gas components for the upper and lower plasma nozzle heads 30X and 30 can be made different according to the film types on the front side surface and the back surface of the wafer 90.

  The outlet 30bx is disposed at the center in the width direction of the inlet 30cx. The suction port 30cx is divided into an inner peripheral side and an outer peripheral side across the blowout port 30bx. A suction passage 30dx extends from the suction port portion on the inner peripheral side and the suction port portion on the outer peripheral side, respectively. It is connected to the exhaust system.

  In the substrate processing apparatus shown in FIG. 9, the arrangement relationship between the plasma nozzle head 30 and the laser irradiation unit 22 of the laser heater 20 is different from that shown in FIG. That is, in the apparatus shown in FIG. 9, the plasma nozzle head 30 is fixed to the bottom plate 51 of the frame 50 with the front end surface and thus the blowout port 30b facing upward. The blowout port 30b is disposed close to the lower side of the outer peripheral edge of the wafer 90 installed on the stage 10, and blows reactive gas in a direction perpendicular to the outer peripheral portion of the back surface of the wafer 90 ( It is disposed on a line that passes through the processing position P and is orthogonal to the extended surface of the support surface 10a).

  As shown in an enlarged view in FIG. 10, a plate-like total reflection member 25 is provided at a position closer to the stage 10 than the outlet 30 b on the tip surface of the plasma nozzle head 30. The surface opposite to the stage 10 side of the total reflection member 25 is a slope inclined upward toward the stage 10 side. This slope serves as a total reflection surface 25a that totally reflects light such as a laser.

  On the other hand, the laser irradiation unit 22 is fixed to the peripheral wall 52 of the frame 50 with the axis line extending laterally away from the plasma nozzle head 30 in the radial direction and directing the laser irradiation direction inward in the radial direction. The laser L emitted from the laser irradiation unit 22 hits the reflection surface 25 a and is reflected obliquely upward, and hits the outer peripheral portion of the back surface of the wafer 90. Thereby, the outer peripheral part of the back surface of the wafer 90 can be locally heated.

Note that the member 34 and the like at the upper end of the plasma nozzle head 30 may be made of a translucent material so as to transmit the laser L.
In the case where the laser from the laser irradiation unit 22 is not linear but conical to collect light toward the reflection surface 25a, the plasma nozzle head 30 is lowered and separated from the wafer 90, and the total reflection member 25 is thickened by that amount, The laser may not interfere with the plasma nozzle head 30.

  As shown in FIG. 9, a cover member 80 having a ring shape along the entire inner circumference is provided at the upper end of the peripheral wall 52 of the frame 50. The cover member 80 has a horizontal portion 81 that forms a horizontal disk shape and extends radially inward from the peripheral wall 52, and a tubular hanging portion 82 that hangs down from the entire circumference of the inner end edge of the horizontal portion 81. The cross section is L-shaped. The cover member 80 includes a retracted position (this state is not shown) that is largely separated above the peripheral wall 52 by an elevating mechanism (not shown), and a set position where the outer peripheral surface of the horizontal portion 81 contacts the inner peripheral surface of the peripheral wall 52 (this The state can be moved up and down. When the wafer 90 is placed on or taken out of the stage 10, the cover member 80 is positioned at the retracted position, and when the wafer 90 is processed, the cover member 80 is positioned at the set position.

In the set position, the inner edge of the horizontal portion 81 and the hanging portion 82 of the cover member 80 are disposed above the processing position P, that is, above the outer peripheral portion of the wafer 90 on the stage 10, and cooperate with the outer peripheral portion of the wafer 90. The upper part of the annular space 50a is covered. Between the cover member 80 and the peripheral wall 52, a space 50b integrally formed with the annular space 50a is formed. The lower end portion of the drooping portion 82 is disposed slightly above the wafer 90 so that the gap 82a (FIG. 10) between the drooping portion 82 and the wafer 90 is very narrow. As a result, the processed reactive gas after hitting the outer peripheral portion of the wafer 90 can be surely confined in the spaces 50a and 50b, and is prevented from flowing toward the center of the upper surface of the wafer 90. Can do. As a result, the upper surface film 92 can be prevented from being damaged. A space 50b between the cover member 80 and the peripheral wall 52 is connected to a suction / exhaust device (not shown) via a suction connector 55 of the cover member 80 and the like. Thereby, the processed gas in the space 50a and the space 50b can be sucked and exhausted.
The suction connector 55 and the suction / exhaust device constitute “annular space suction means”.

  The substrate processing apparatus shown in FIG. 11 uses an ozonizer 70 as a reactive gas supply source of the reactive gas supply means in place of the atmospheric pressure glow discharge type plasma nozzle heads 30 and 30X of the above-described embodiment. Yes. The ozone generation method of the ozonizer 70 may be any type such as silent discharge and creeping discharge. The ozonizer 70 is installed apart from the frame 50. An ozone supply pipe 71 extends from the ozonizer 70, and the ozone supply pipe 71 reacts with the peripheral wall 52 of the frame 50 via a supply connector 72 provided on the bottom plate 51 radially outside the laser irradiation unit 22 of the frame 50. It connects to the property gas path 52b. The supply connectors 72 are arranged in the same number (for example, five) as the laser irradiation units 22 at equal intervals in the circumferential direction so as to correspond one-to-one to the same circumferential positions as the laser irradiation units 22. A supply pipe 71 is branched and connected to each supply connector 72. Reactive gas passages 52 b extend from the supply connectors 72.

The reactive gas passage 52b reaches the inner peripheral surface of the peripheral wall 52, and the translucent blowing nozzle 36 projects obliquely upward therefrom, and the tip of the blowing nozzle 36 projects from the wafer 90 installed on the stage 10. It is the same as that of FIG. 6 that it is very close to the back side of the outer peripheral portion.
The ozonizer 70, the ozone supply pipe 71, the supply connector 72, the frame 50 having the reactive gas passage 52b, and the blowout nozzle 36 are components of “reactive gas supply means”.

  Ozone as the reactive gas generated by the ozonizer 70 is blown out from the blowing nozzle 36 through the ozone supply pipe 71, the supply connector 72, and the reactive gas path 52b in this order. Since the blow-out nozzle 36 is disposed in the very vicinity of the outer peripheral portion of the back surface of the wafer 90, the film 92c can be efficiently removed by being reliably applied to the outer peripheral portion of the back surface of the wafer 90 before the ozone diffuses and deactivates. 6 and FIG. 6 that the laser L can pass through the blow nozzle 36 even if the blow nozzle 36 interferes with the optical path of the laser L from the laser heater 20, and the target portion of the wafer 90 can be reliably heated. It is the same as that. Further, the processed ozone passes through the suction path, that is, the suction path 53d near the blowout nozzle 36, the suction connector 57, or the like, or the exhaust path such as the space 50a, the gap between the labyrinth seal 60, and the suction path 51c. The suction and exhaust by a suction exhaust device (not shown) is the same as that in FIGS.

  A cover member 80 is provided above the upper peripheral wall 53. The cover member 80 can be moved up and down between an upward retracted position (indicated by a phantom line in FIG. 11) and a set position (indicated by a solid line in FIG. 11) by a lifting mechanism (not shown), as in FIG. It has become. The cover member 80 in the set position is in contact with the upper surface of the upper peripheral wall 53 and extends inward in the radial direction, and the drooping portion 82 at the inner end thereof is positioned above the outer peripheral edge of the stage 10. Thus, the cover member 80 alone covers the annular space 50a. As a result, the processed ozone is prevented from flowing toward the center of the upper surface of the wafer 90, as in FIG.

  The substrate processing apparatus shown in FIG. 12 uses an infrared heater 120 as a radiant heater instead of the laser heater 20 of the above-described embodiment. As shown in FIGS. 12 and 13, the infrared heater 120 includes a light source including an infrared lamp 121 such as a halogen lamp and an optical system 122 for convergent irradiation, and has an annular shape that extends over the entire circumference of the frame 50. There is no. That is, the infrared lamp 121 is an annular light source that extends over the entire circumference of the frame 50, and the optical system 122 is also disposed over the entire circumference of the frame 50. The optical system 122 includes a condensing system such as a parabolic reflector, a convex lens, and a cylindrical lens, a wavelength extraction unit such as a bandpass filter, and the like, and further includes a focus adjustment mechanism. The optical system 122 passes the infrared rays from the infrared lamp 121 through a bandpass filter, collects it with a condensing system such as a parabolic reflector and a lens, and converges it on the entire outer periphery of the back surface of the wafer 90. . As a result, the film 92c on the outer peripheral portion of the back surface can be heated locally and all at once over the entire periphery. As the infrared lamp 121, a far infrared lamp may be used, or a near infrared lamp may be used. The emission wavelength is, for example, 760 nm to 10000 nm, and light matching the absorption wavelength of the film 92 c is extracted from the light with a band pass filter. Thereby, the heating efficiency of the film 92c can be further increased.

Inside the infrared heater 120, a lamp cooling path 125 is formed over the entire circumference. A refrigerant supply source (not shown) is connected to the lamp cooling path 125 via a refrigerant forward path 126 and a return path 127, and the refrigerant is circulated. It has become so. Thereby, the infrared heater 120 can be cooled. For example, water, air, helium gas or the like is used as the refrigerant. When air or water is used, it may be discharged from the return path 127 without returning to the refrigerant supply source. The refrigerant supply source for cooling the heater may be shared with the refrigerant supply source for absorbing the base material.
The lamp cooling path 125, the forward path 126, the return path 127, and the heater cooling refrigerant supply source constitute “radiant heater cooling means”.

  As the reactive gas supply source of the reactive gas supply means, the ozonizer 70 is used as in the apparatus of FIG. The ozonizer 70 is connected to a plurality of supply connectors 72 of the frame 50 through an ozone supply pipe 71. The number of supply connectors 72 is relatively large, for example, eight. These supply connectors 72 are arranged at equal intervals in the circumferential direction of the upper portion of the outer peripheral surface of the peripheral wall 52.

  The upper portion of the peripheral wall 52 is provided as a blowout path and a blowout port forming member. That is, in the upper part of the peripheral wall 52, the reactive gas passages 73 connected to the supply connectors 72 are formed horizontally toward the inner side in the radial direction and in an annular shape over the entire circumference. The reactive gas path 73 opens to the entire inner periphery of the peripheral wall 52, and serves as an annular outlet 74. The height of the blow-out port 74 is located slightly below the upper surface of the stage 10 and thus the back surface of the wafer 90 to be placed thereon, and surrounds the entire periphery in the vicinity of the outer peripheral edge of the wafer 90. Is arranged.

Ozone from the ozonizer 70 is introduced into the connection position of each supply connector 72 of the reactive gas passage 73 and blown radially inward from the entire circumference of the blowout port 74 while spreading over the entire circumferential direction of the reactive gas passage 73. . Thereby, ozone can be sprayed at once on the entire circumference of the outer peripheral portion of the back surface of the wafer 90, and the film 92c on the entire circumference can be efficiently removed.
In the apparatus shown in FIG. 12, since the entire circumference of the wafer 90 can be processed at a time as described above, it is not always necessary to rotate the stage 10, but it is preferable to rotate it in order to make the processing uniform in the circumferential direction. .

  In the apparatus of FIG. 12, when the cover member 80 is positioned at the set position, the suction path 53 d is formed over the entire circumference between the upper surface of the peripheral wall 52. The suction path 53d is connected to a suction / exhaust device (not shown) via a suction connector 57 and the like provided in the cover member 80, whereby the processed reactive gas is sucked and exhausted from the periphery of the outer peripheral portion of the wafer 90. can do.

FIG. 14 uses the same apparatus as FIG. 12, and the outer edge of the wafer protrudes 3 mm from the stage 10, and the water temperature in the refrigerant chamber 41 is 5 ° C., 20 ° C., and 50 ° C., respectively. 3 shows the experimental results of measuring the surface temperature of the wafer with respect to the distance in the radial inner direction from the vicinity of the heated portion of the outer edge of the wafer. The output conditions of the infrared heater 120 are as follows.
Light source: annular halogen lamp Converging optical system: parabolic reflector Light emission wavelength: 800-2000 nm
Output: 200W
Width of local heating area: 2mm
As shown in FIG. 14, when the water temperature is 20 ° C., which is normal temperature, in the vicinity of the heated portion on the outer edge of the wafer, the temperature is about 80 ° C. due to heat conduction from the heated portion (400 ° C. or higher at the heated portion). From there, it was confirmed that the portion inside 9 mm or more in the radial direction was kept at a low temperature of 50 ° C. or less, and damage to the film could be suppressed.

  By the way, as shown in FIG. 15, the lifetime of the oxygen atom radical obtained by decomposing ozone depends on the temperature, and is sufficiently long near 25 ° C., but is halved near 50 ° C. On the other hand, since heating is performed to ensure reaction with the film 92c, the temperature of the ozone blowing path may increase.

In view of this, the base material processing apparatus shown in FIG. 16 is provided with a blowout path cooling (temperature control) means. That is, a reactive gas cooling path 130 is provided inside the peripheral wall 52 of the frame 50 as a blowout path forming member, and a refrigerant supply source (not shown) is connected to the reactive gas cooling path 130 via a refrigerant forward path 131 and a return path 132. The refrigerant is circulated. For example, water, air, helium gas or the like is used as the refrigerant. When air or water is used, it may be discharged from the return path 132 without returning to the refrigerant supply source. The refrigerant supply source for cooling the blowout path may be shared with the refrigerant supply source for absorbing the base material. As a result, the ozone passing through the reactive gas passage 52b can be cooled, the decrease in the amount of oxygen atom radicals can be suppressed, and the activity can be maintained. As a result, the removal efficiency of the film 92c can be improved.
In the substrate processing apparatus of FIG. 16, the same ozonizer as that of FIG. 11 and the like is used as a reactive gas supply source. However, a reactive gas cooling path 130 is provided in the apparatus using the plasma nozzle head 30 of FIG. The reactive gas passage 52b may be cooled.

An inert gas nozzle 140 as an inert gas spraying member is provided above the center of the stage 10 and thus the wafer 90 placed thereon, with the blowout port directly below. The upstream end of the inert gas nozzle 140 is connected to an inert gas supply source (not shown). For example, nitrogen gas is introduced into the inert gas nozzle 140 as an inert gas from the inert gas supply source and is blown out from the outlet. The blown nitrogen gas is diffused radially from the center to the radially outer side along the upper surface of the wafer 90. Eventually, the nitrogen gas reaches the gap 82 a between the vicinity of the outer peripheral portion of the upper surface of the wafer 90 and the cover member 80, and a part of the nitrogen gas tries to go around to the back side of the wafer 90. This flow of nitrogen gas can prevent the processed reactive gas around the back side of the outer peripheral portion of the wafer 90 from flowing around to the front side of the base material, and thus surely prevent leakage from the gap 82a. Can do.
The inert gas nozzle 140 is retracted so as not to get in the way when the wafer 90 is set on or taken out of the stage 10.

  In the substrate processing apparatus of FIG. 16, the laser heater 20 is used as the radiant heater, but instead of this, an infrared heater 120 may be used as shown in FIG. 17. The infrared heater 120 has an annular shape and extends around the entire circumference of the frame 50 as in the case of FIG.

  In the substrate processing apparatus shown in FIG. 18, the supply connector 72 from the ozonizer 70 is disposed between the laser irradiation unit 22 of the bottom plate 51 of the frame 50 and the labyrinth seal 60. The supply connector 72 is connected to a tubular blowing nozzle 75 as a blowing path forming member. The blowout nozzle 75 extends straight up from the supply connector 72, hits the vicinity of the bottom of the peripheral side surface of the stage 10, bends, and extends obliquely upward along the taper of the peripheral side surface of the stage 10. The opening at the tip of the blowing nozzle 75 serves as a blowing port and is located near the upper edge of the peripheral side surface of the stage 10. This blowout port faces the outer peripheral portion of the back surface of the wafer 90 placed on the stage 10 and blows out ozone to the film 92c.

According to this configuration, by passing the coolant through the coolant chamber 41 inside the stage 10, not only the wafer 90 is cooled by absorbing heat, but also the blowing nozzle 75 can be cooled. Thus, the base material heat absorbing means also serves as the blowout path cooling (temperature control) means. Therefore, it is not necessary to form the reactive gas cooling path 130 and the like in FIG. 16, and the cost can be reduced.
In addition, it is preferable to apply a friction reducing material such as grease for reducing friction due to rotation of the stage 10 on the peripheral side surface of the stage 10 or the outer peripheral surface of the blowout nozzle 75.

  In the substrate processing apparatus shown in FIG. 19, a step 12 is formed on the entire circumference of the outer peripheral portion of the upper surface of the stage 10. Thus, when the wafer 90 is installed, a recess (gas reservoir) 12 a is formed between the step 12 and the wafer 90. The recess 12a extends over the entire circumference of the stage 10 and opens radially outward. The depth along the radial direction of the recess 12a is, for example, about 3 to 5 mm.

  The ozone blown out from the blowout nozzle 36 enters the recess, that is, the gas reservoir 12a, and temporarily stays there. As a result, a sufficient reaction time between ozone and the film 92c on the outer periphery of the back surface of the wafer 90 can be ensured, and the processing efficiency can be increased.

  In the substrate processing apparatus shown in FIG. 20, an enclosure 150 is provided on the radially outer side of the outer peripheral portion of the stage 10. A base material insertion hole 10a is formed in the inner peripheral side wall of the enclosure 150 facing the stage 10 side. The protruding outer peripheral portion of the wafer 90 placed on the stage 10 is inserted into the enclosure 150 through the base material insertion hole 10a. A front end portion of the plasma nozzle head 30 is penetrated through the outer peripheral side wall of the enclosure 150, whereby a reactive gas blow-out port is disposed inside the enclosure 150. On the other hand, as the radiant heater, for example, the laser irradiation unit 22 of the laser heater 20 is arranged at the lower side of the enclosure 150, that is, outside the enclosure 150.

The enclosure 150 is made of a translucent material such as quartz, borosilicate glass, or transparent resin. As a result, the laser beam L from the laser irradiation unit 22 passes through the bottom plate of the enclosure 150 and is locally irradiated to the outer peripheral portion of the back surface of the wafer 90. As a result, the outer peripheral portion of the back surface of the wafer 90 can be heated locally. On the other hand, reactive gases such as oxygen radicals and ozone generated by the plasma nozzle head 30 are blown out into the enclosure 150, hitting the locally heated portion, and the film 92c there can be reliably removed. The treated reactive gas is prevented from leaking outside by the enclosure 150. Then, the air is sucked and exhausted from the suction port of the plasma nozzle head 30.
In addition, the enclosure 150 should just comprise the bottom plate which faces the laser irradiation unit 22 with a translucent material.

  FIG. 21 shows another embodiment of the optical system of the radiation heater. An optical fiber cable 23 (waveguide) is optically connected to the light source 21 of the laser heater 20 as an optical system that wire-transmits the emitted light to the outer periphery of the wafer 90. The optical fiber cable 23 is configured by a bundle of many optical fibers. A bundle of these optical fibers extends from the laser light source 21 and branches in a plurality of directions to form a plurality of branch cables 23a. Each branch cable 23a may be composed of a single optical fiber or a bundle of a plurality of optical fibers. The leading ends of the branch cables 23a extend to the outer periphery of the stage 10 and are spaced apart from each other at equal intervals along the circumferential direction of the stage 10. The front end portion of each branch cable 23a is disposed upward so as to face the wafer 90 at a position to be processed P, that is, directly below the vicinity of the outer peripheral portion of the back surface of the wafer 90 placed on the stage 10. Plasma nozzle heads 30 are provided sideways so as to have a one-to-one correspondence with the tip of each branch cable 23a. Although not shown, it is preferable to provide a laser irradiation unit 22 at the tip of each branch cable 23a.

According to this configuration, the laser from the light source 21 is transmitted without being diverged toward the outer peripheral portion of the back surface of the wafer 90 by the optical fiber cable 23. In addition, the signals are distributed and transmitted to different positions in the circumferential direction by the branch cable 23a. And it is radiate | emitted upwards from the front end surface of each branch cable 23a. Thereby, laser irradiation can be performed on the outer peripheral portion of the back surface of the wafer 90 from the vicinity thereof. Also, the point laser beam from one point light source 21 can be distributed and irradiated to a plurality of locations in the circumferential direction of the wafer 90. As a result, the film can be removed by simultaneously heating the plurality of locations.
Furthermore, the location of the light source 21 can be set freely. The optical fiber can be easily routed.
Note that a converging optical member such as a cylindrical lens may be provided at the tip of the branch cable 23a so that the emitted light is converged. A plurality of light sources 21 may be provided, and each optical fiber cable 23 from each light source 21 may be extended toward a predetermined circumferential position. The arrangement relationship between the tip of the optical fiber and the outlet can be variously arranged such that the tip of the optical fiber is inclined with respect to the wafer 90 and the outlet of the plasma nozzle head 30 is placed directly below. Of course, the ozonizer 70 may be used instead of the plasma nozzle head 30, and an infrared lamp may be used instead of the laser light source 21.

  FIG. 22 shows a modified form of the outlet forming member such as the outlet nozzle 36 of the apparatus shown in FIG. As shown in FIG. 22A, on the peripheral wall of the blow nozzle 36X, a plurality of swirl guide holes 36b having a pore shape as a swirl flow forming portion are spaced apart from each other at equal intervals in the circumferential direction (for example, 4 One) is formed. The swivel guide hole 36b penetrates the peripheral wall of the nozzle 36X from the outer peripheral surface to the inner peripheral surface so as to extend in the substantially tangential direction of the inner periphery of the nozzle 36X, that is, the inner peripheral surface of the outlet 36a. Moreover, as shown in FIG. 6B, the nozzle 36X is inclined toward the tip end direction from the outer peripheral surface of the peripheral wall of the nozzle 36X toward the inner peripheral surface (that is, radially inward). An end portion on the outer peripheral side of each turning guide hole 36b is connected to the blowout path 52b, and an end portion on the inner peripheral side is connected to the blowout port 36a. Therefore, the turning guide hole 36b constitutes a communication passage between the blowout passage 52b and the blowout port 36a or a passage portion upstream of the blowout port.

  According to this blowing nozzle 36X, the reactive gas from the blowing path 52b can be blown obliquely into the blowing port 36a, and a swirling flow can be formed along the inner peripheral surface of the blowing port 36a. Thereby, the reactive gas can be made uniform. Moreover, since the reactive gas passes through the fine swirl guide hole 36b and then blows out to the relatively wide outlet 36a, it can be made more uniform due to pressure loss. The uniform swirling flow of the reactive gas is blown out from the nozzle 36 </ b> X and hits the outer periphery of the back surface of the wafer 90, so that a good film removal process can be performed.

  FIG. 23 shows a modification of the substrate heat absorbing means. The refrigerant chamber inside the stage 10 is partitioned by a horizontal partition plate 45 into a first chamber portion 41U on the upper side (support surface side) and a second chamber portion 41L on the lower side (opposite side to the support surface). Yes. The partition plate 45 is smaller in diameter than the inner diameter of the peripheral wall of the stage 10, and the upper and lower first and second chamber portions 41 </ b> U and 41 </ b> L are connected to the outer periphery side of the partition plate 45. An end portion of a pipe constituting the refrigerant supply path 42 is connected to the central portion of the partition plate 45, and the refrigerant supply path 42 is connected to the upper first chamber portion 41U. In addition, an end of a pipe constituting the refrigerant discharge path 43 is connected to the center of the bottom plate of the stage 10, and the refrigerant discharge path 43 is connected to the lower second chamber portion 41L.

The refrigerant is introduced from the refrigerant supply path 42 to the center portion of the first chamber portion 41U on the upper side (support surface side), and flows so as to expand radially outward. Then, it goes around the outer edge of the partition plate 45, enters the second chamber portion 41 </ b> L on the lower side (opposite to the support surface), flows inward in the radial direction, and is discharged from the central refrigerant discharge passage 43.
As a result, the entire stage 10 can be reliably cooled, and the wafer 90 can be reliably cooled uniformly, and the upper surface film 92 can be reliably protected. Since the coolant is first introduced into the first chamber portion 41U on the side close to the support surface 10a and thus the wafer 90, the heat absorption efficiency can be further increased.

  In the embodiment of FIG. 23, the refrigerant supply path 42 and the refrigerant discharge path 43 are arranged in parallel. However, as shown in FIG. 24, the refrigerant supply path 42 is passed through the refrigerant discharge path 43 to form a double tubular shape. It may be configured.

  FIG. 25 shows another modification of the substrate heat absorbing means. A spiral refrigerant passage 46 is provided inside the stage 10. A refrigerant supply passage 42 is connected to an end portion on the outer peripheral side of the spiral refrigerant passage 46, and a refrigerant discharge passage 43 is connected to an end portion on the center side. Thus, the refrigerant flows in a spiral shape from the outer peripheral side of the refrigerant passage 46 to the inner peripheral side. Therefore, the side near the outer periphery of the wafer 90 can be sufficiently cooled. As a result, the heat transmitted from the outer peripheral portion of the wafer 90 can be reliably absorbed, and the film 92 on the upper surface can be reliably protected.

Although not shown in detail, not only the refrigerant discharge path 43 on the center side but also the refrigerant supply path 42 on the outer peripheral side is passed through the center shaft 11 of the stage 10. The refrigerant supply path 42 extends, for example, radially outward from the center axis 11 side between the bottom plate of the stage 10 and the refrigerant passage 46, and continues to the outer peripheral side end of the refrigerant passage 46.
When the stage 10 is fixed while the frame 50 is rotated, it is not necessary to pass the refrigerant supply path 42 into the central shaft 11.

The mechanism for flowing the refrigerant from the outer peripheral side of the stage 10 toward the center is not limited to the spiral structure of FIG. For example, the refrigerant passage in the stage 10 shown in FIG. 26 includes a plurality of concentric circular passages 47 and a communication passage 48 that connects the annular passages 47. A plurality of communication paths 48 are provided at equal intervals in the circumferential direction between adjacent annular paths 47. The communication path 48 on the outer side in the radial direction and the communication path 48 on the inner side in the radial direction are arranged so as to be offset from each other in the circumferential direction with one annular path 47 interposed therebetween. In the outermost annular passage 47, the refrigerant supply passage 42 is branched and connected to a plurality of positions spaced at equal intervals in the circumferential direction. The base end portion of the refrigerant discharge passage 43 is connected to the central annular passage 47.
Accordingly, as indicated by the arrows in FIG. 26, the refrigerant branches and flows in the circumferential direction along the outer annular path 47, and then merges in the communication path 48 and flows into the inner annular path 47. Then, the flow is diverted again in the circumferential direction, and the flow is repeated from the outer peripheral side of the stage 10 toward the center while repeating this.

The stage 10 shown in FIGS. 27 (a) and 27 (b) is a refrigerant chamber 41 having a hollow shape as in FIG. The refrigerant supply path 42 is branched into a plurality of lines and is connected to positions spaced apart at equal intervals in the circumferential direction of the outer peripheral portion of the refrigerant chamber 41. A refrigerant discharge path extends from the center of the refrigerant chamber 41. As a result, the refrigerant is introduced into the outer peripheral portion of the refrigerant chamber 41 and flows toward the center. The refrigerant chamber 41 constitutes a centripetal refrigerant passage.
23 and 24, the refrigerant supply path 42 and the refrigerant discharge path 43 may be reversed from each other. In this case, the refrigerant flow in the upper refrigerant chamber 41U is directed from the outer peripheral side toward the center.

  FIG. 28 shows a base material heat absorption means other than the refrigerant system. That is, the stage 10 incorporates a Peltier element 160 as a base material heat absorption means. The Peltier element 160 is disposed with the heat absorption side facing upward (the upper surface 10 a side of the stage 10) and close to the upper surface 10 a of the stage 10. As a result, the wafer 90 can absorb heat through the upper plate of the stage 10. Note that a fan, a fin, or the like may be provided below the Peltier element 160 of the stage 10 in order to promote heat dissipation from the heat dissipation side of the Peltier element 160.

  FIGS. 29A and 29B show a stage 10 incorporating a vacuum chuck mechanism as a substrate fixing means. A large number of suction holes 13 are dispersedly formed on the upper plate of the stage 10 made of a metal having a good thermal conductivity such as aluminum, and these suction holes 13 are sucked by a vacuum pump or the like (not shown) via a suction path 14. It is connected to means. The suction hole 13 is as small as possible. As a result, a sufficient contact area between the stage 10 and the wafer 90 can be secured. As a result, the heat absorption efficiency of the wafer 90 can be sufficiently ensured.

  30A and 30B show a modification of the vacuum chuck mechanism. Instead of the spot-like suction holes 13, suction grooves 15 are formed on the upper surface of the stage 10. The suction groove 15 has a plurality of concentric annular grooves 16 and a communication groove 17 that connects the annular grooves 16. A plurality of communication grooves 17 are provided at equal intervals in the circumferential direction between adjacent annular grooves 16. The communication groove 17 on the outer side in the radial direction and the communication groove 17 on the inner side in the radial direction are arranged so as to be offset from each other in the circumferential direction with one annular groove 16 therebetween. The annular groove 16 and the communication groove 17 are as narrow as possible. As a result, the contact area between the stage 10 and the wafer 90 and thus the heat absorption efficiency of the wafer 90 can be sufficiently secured.

In the substrate processing apparatus according to the embodiment shown in FIGS. 31 and 32, a processing head H is provided on the side of the stage 10. The processing head H is disposed below the upper surface of the stage 10. The processing head H is provided with a blowing nozzle 75 and an exhaust nozzle 76.
An ozone supply pipe 71 extends from an ozonizer 70 as a reactive gas supply source, and this ozone supply pipe 71 is connected to the base end portion of the blowing nozzle 75 via a connector 72 of the processing head H. The blowing nozzle 75 is disposed below the processing position (the outer peripheral portion of the wafer 90 on the stage 10). As shown in FIG. 31, the tip portion of the blow-out nozzle 75 is substantially inclined along the tangential direction of the outer periphery of the wafer 90 in a plan view and slightly inclined toward the stage 10 side, that is, toward the radially inner side of the wafer 90, and As shown in FIG. 32, it is inclined upward toward the wafer 90 in a front view. The blowout opening at the tip of the blowout nozzle 75 faces the vicinity of the processing position P (the back surface of the outer peripheral portion of the wafer 90).

A connector 77 connected to the exhaust nozzle 76 is provided on the side of the processing head opposite to the blowout connector 72. An exhaust pipe 78 extends from the connector 77, and the exhaust pipe 78 is connected to an exhaust means 79 including an exhaust pump.
The exhaust nozzle 76 is disposed below the processing position P (the outer peripheral portion of the wafer 90 on the stage 10). As shown in FIG. 31, the front end portion of the exhaust nozzle 76 is directed straight in the tangential direction of the outer periphery of the wafer 90 in a plan view, and tilted upward toward the wafer 90 in a front view as shown in FIG. ing. The suction port at the tip of the exhaust nozzle 76 is positioned at substantially the same height as the blowout port of the blowout nozzle 75 (just below the back surface of the wafer 90).

  As shown in FIG. 31, the tip portions of the blowout nozzle 75 and the exhaust nozzle 76 are arranged so as to face each other across the processing position P along one tangential direction of the outer periphery of the wafer 90 in plan view. . A processing position P is disposed between the blowout port at the tip of the blowout nozzle 75 and the suction port at the tip of the exhaust nozzle 76. The blowing nozzle 75 is disposed on the upstream side and the exhaust nozzle 76 is disposed on the downstream side along the rotation direction of the stage 10 and the wafer 90 (for example, clockwise in plan view). The distance between the blowout port of the blowout nozzle 75 and the suction port of the exhaust nozzle 76 takes into consideration the reaction temperature of the film 92c to be removed, the rotational speed of the stage 10, the heating capability of the laser heater 20, etc. It is appropriately set within a range of several tens of mm.

  The suction port diameter of the exhaust nozzle 76 is larger than the outlet port diameter of the outlet nozzle 75, for example, about 2 to 5 times. For example, the outlet diameter is about 1 to 3 mm, while the inlet diameter is about 2 to 15 mm.

  As shown in FIG. 32, a laser irradiation unit 22 of the laser heater 20 is provided as a radiation heater at the lower side of the processing head H. The laser irradiation unit 22 is disposed below the nozzles 75 and 76 and, as shown in FIG. 31, is disposed between the blowing nozzle 75 and the tip of the exhaust nozzle 76 in a plan view. A processing position P is located immediately above the laser irradiation unit 22.

  In the above configuration, the laser light from the laser light source 21 is converged and irradiated directly from the laser irradiation unit 22 through the optical fiber cable 23. Thereby, the back surface of the outer peripheral part of the wafer 90 is locally heated. The locally heated portion moves to the downstream side in the rotation direction by the rotation of the stage 10 while maintaining a high temperature for a while. Therefore, the outer peripheral portion of the wafer 90 is at a high temperature not only in the irradiated portion (processed position P) directly above the laser irradiation unit 22 but also in the downstream portion in the rotational direction. Of course, the irradiated portion P directly above the laser irradiation unit 22 has the highest temperature, and the temperature decreases from there toward the downstream side in the rotation direction. A distribution curve T shown by a two-dot chain line in FIG. 31 shows the temperature distribution of the wafer 90, and the distribution of the high temperature region is biased to the downstream side in the rotation direction with the irradiated portion P as the center.

  In parallel with the laser heating and the stage rotation, the ozone gas of the ozonizer 70 is blown out from the blowout port of the blowout nozzle 75 through the supply pipe 71, the connector 72 and the blowout nozzle 75 in order. The ozone is sprayed around the irradiated portion (processed position P) on the back surface of the outer peripheral portion of the wafer 90 and flows toward the exhaust nozzle 76 along substantially the tangent line of the outer periphery of the wafer 90 of the irradiated portion. . This gas flow is along the bias direction of the temperature distribution of the wafer 90. Accordingly, the reaction with the film 92c can be caused not only in the irradiated portion P immediately after the blowing but also in the portion on the exhaust nozzle 76 side downstream from the irradiated portion P. Thereby, processing efficiency can be improved.

  At the same time, the suction means 79 is driven. As a result, the treated ozone gas and reaction by-products can be guided to the suction port of the exhaust nozzle 76 and sucked and exhausted. Since the suction port is larger than the blowout port, the treated ozone gas or the like can be reliably captured and sucked, and the treated ozone gas or the like can be prevented from diffusing.

The present invention is not limited to the above embodiment, and various modifications can be made as necessary.
The component of the unnecessary object to be removed is not limited to an organic substance such as fluorocarbon, and may be an inorganic substance.
The process gas and thus the reactive gas can be appropriately selected according to the components of the target film, such as fluorine-based as well as oxygen-based. It is advisable to adjust the temperature (cooling or warming) of the blowing path from the reactive gas supply source to the blowing port so that the activity can be maintained according to the gas type.
The point light of the point light source such as the laser heater 20 may be converted into linear light by an optical system such as a convex lens or a cylindrical lens, and irradiated to a certain range along the circumferential direction of the wafer 90.
The infrared lamp 121 of the infrared heater 120 may be a point light source or a linear light source instead of the annular light source.
A radiant heater is placed on the front side of the support surface of the stage or its extended surface, and a reflector is installed on the back side of the support surface or its extended surface, and the heat rays from the radiant heater are reflected by the reflector, and It may be applied to the outer periphery of the back surface of the material.

  The present invention can be used, for example, for removing unnecessary films on the outer periphery in a semiconductor wafer manufacturing process or a liquid crystal display substrate manufacturing process.

FIG. 3 is a front cross-sectional view showing the substrate processing apparatus according to the first embodiment of the present invention and taken along line II in FIG. 2. It is a top view of the said apparatus. It is front sectional drawing which expands and shows the film removal process part of the said apparatus. It is a graph which shows the experimental result which measured wafer temperature with respect to the distance to the radial inside direction from the vicinity of the to-be-heated site | part of the outer edge of a wafer with the apparatus similar to FIG. 6 is a graph showing another experimental result of measuring the wafer temperature with respect to the distance from the vicinity of the heated portion of the outer edge of the wafer to the radially inward direction using the same apparatus as in FIG. 1. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as a reactive gas supply means. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as a reactive gas supply means. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as a reactive gas supply means. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as the arrangement | positioning relationship of a radiant heater and a reactive gas supply means. It is front sectional drawing which expands and shows the film | membrane removal process part of the apparatus of FIG. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as the reactive gas supply source of a reactive gas supply means. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as a radiant heater and a reactive gas supply means. It is a plane sectional view of the above-mentioned device which meets an XIII-XIII line of FIG. It is a graph which shows the experimental result which measured the wafer temperature with respect to the distance to the radial inside direction from the vicinity of the to-be-heated site | part of the outer edge of a wafer with the apparatus similar to FIG. It is a graph which shows the ozonolysis half life with respect to temperature. It is front sectional drawing which shows the base-material processing apparatus which concerns on the modified embodiment which added the nozzle cooling part, the inert gas supply part, etc. It is front sectional drawing which shows the base-material processing apparatus which concerns on embodiment which changed the radiation heater in FIG. It is front sectional drawing which shows the base-material processing apparatus which concerns on modified embodiment, such as a nozzle cooling part. It is front sectional drawing which shows the base-material processing apparatus which concerns on the modified embodiment which added the gas reservoir. It is a description front view which shows embodiment which added the translucent enclosure. It is an explanatory front view showing an embodiment using a plurality of optical fiber cables as an optical system of a radiation heater. It is front sectional drawing of the blower outlet formation member which has a swirl flow formation part. It is side surface sectional drawing of the blower outlet formation member which has the said turning flow formation part. It is a description front view of the stage which concerns on the modification aspect of a base-material heat absorption means. It is a description front view of the stage which concerns on the modification aspect of a base-material heat absorption means. It is explanatory drawing top view of the stage which concerns on the modification aspect of a base-material heat absorption means. It is explanatory drawing top view which shows the modification aspect of the base-material heat absorption means of a stage. It is explanatory drawing top view of the stage which concerns on the modification aspect of a base-material heat absorption means. It is the description front view of the stage of Fig.27 (a). It is a description front view of the stage which concerns on the modification aspect which used the Peltier device as a base-material heat absorption means. It is a top view of the stage incorporating the vacuum chuck mechanism as a base-material fixing means. It is explanatory front sectional drawing of the stage of Fig.29 (a). It is a top view of the stage which concerns on the modification aspect of a vacuum chuck mechanism. It is commentary front sectional drawing of the stage of Fig.30 (a). It is plane explanatory drawing which shows the base-material processing apparatus which concerns on other embodiment of the nozzle structure of blowing and exhaust. It is front explanatory drawing of the base-material processing apparatus of FIG. It is a graph which shows the relationship between the etching rate of the organic film by ozone, and temperature.

Explanation of symbols

10 Stage 10a Support surface 12 Step 12a Recess (Gas pool)
20 Laser heater (radiant heater)
21 Laser light source 22 Laser irradiation unit (irradiation unit)
23 Optical fiber cable (waveguide, transmission optical system)
25 Total reflection member 30 Plasma nozzle head (reactive gas supplier)
33, 36 Air outlet forming member 41 Refrigerant chamber (component of heat absorbing means)
50 frame 50a annular space 52 peripheral wall (blowing path forming member)
52b Air outlet 60 Labyrinth seal 70 Ozonizer (reactive gas supplier)
75 Blowout nozzle (Blowout path forming member)
76 Exhaust nozzle (suction exhaust path forming member)
80 Cover member 90 Base material 92c Film on the outer periphery of the back surface of the base material (unnecessary)
120 Infrared heater (radiant heater)
121 Infrared lamp (light source)
122 Optical system 140 Inert gas blowing nozzle (inert gas blowing member)
P Processing position

Claims (24)

An apparatus for removing unnecessary materials coated on the outer periphery of a substrate,
(A) a stage having a support surface for supporting the substrate;
(B) a radiant heater that locally irradiates the processing position where the outer peripheral portion of the base material supported by the support surface should exist, and locally heats the processing position ;
(C) continuous with the source of the reactive gas for the undesired removal, the arranged near the treated position, forming a reactive gas, the outlet blowing out toward the localized heated the treated location A blowout port forming member;
And the outlet forming member is made of a translucent material . The substrate processing apparatus according to claim 1, wherein the translucent material is any one of quartz, acrylic, and transparent resin . The substrate processing apparatus according to claim 2, wherein the transparent resin is transparent polytetrafluoroethylene or transparent vinyl chloride . 2. The substrate processing apparatus according to claim 1, wherein the translucent material is a tetrafluoroethylene-purple oloalkyl vinyl ether copolymer (PFA) . Either of the irradiation part of the said heat ray of the said radiant heater and a blower outlet is substantially arrange | positioned on the line | wire which passes along the said to-be-processed position, and is orthogonal to the said support surface . substrate processing apparatus according to any one. The irradiation part of the heat ray of the radiant heater is substantially disposed on an orthogonal line that passes through the processing position and is orthogonal to the support surface, and the outlet is oblique to the orthogonal line through the processing position. It arrange | positions on the line | wire which makes | forms , The base-material processing apparatus in any one of Claims 1-4 characterized by the above-mentioned. The direction in which the reactive gas blows out from the outlet is substantially along a tangent line at a position to be processed of the substrate as viewed from a direction orthogonal to the support surface . The substrate processing apparatus described in 1. The substrate processing according to claim 7 , further comprising an exhaust nozzle having a suction port facing the blowing port and a position to be processed of the substrate when viewed from a direction orthogonal to the support surface. apparatus. The substrate processing apparatus according to claim 8 , wherein the suction port is larger than the blowout port . The substrate processing apparatus according to claim 9 , wherein the suction port has a diameter 2 to 5 times that of the blowout port . When viewed from a direction perpendicular to the supporting surface, the substrate processing apparatus according to claim 8, wherein the irradiating portion is disposed between the air outlet and the inlet . The substrate processing according to any one of claims 7 to 11 , further comprising a rotation drive mechanism that rotates the stage about a central axis, wherein a rotation direction of the rotation drive mechanism is along the blowing direction. apparatus. Substrate processing apparatus according to any one of claims 1 to 12, characterized in that a total reflection member for totally reflecting heat rays from the radiant heater to the object to be processed position.   The blowout passage forming member that forms a blowout passage that guides the reactive gas to the blowout port, and the temperature of the blowout passage forming member is adjusted by a blowout passage temperature adjusting means. The substrate processing apparatus according to any one of 13.   The substrate processing apparatus according to claim 1, wherein the stage is provided with heat absorption means for absorbing heat from the support surface.   The blow-out path forming member that forms a blow-out path that guides the reactive gas to the blow-out port, and the blow-out path forming member is cooled by the heat absorbing means along the stage. 15. The substrate processing apparatus according to 15. A frame that surrounds the stage in the circumferential direction and forms an annular space with the stage;
A rotation drive mechanism for rotating the stage relative to the frame around a central axis;
A labyrinth seal that seals between the back side opposite to the support surface side of the stage and the frame while allowing relative rotation;
The substrate processing apparatus according to any one of claims 1 to 16, further comprising:   The frame is provided with a cover member that extends toward the stage side, covers the processing position, and covers the annular space alone or in cooperation with the outer peripheral portion of the base material installed on the stage. The substrate processing apparatus according to claim 17.   The substrate processing apparatus according to claim 18, wherein the cover member can be retracted from a position covering the annular space.   The substrate processing apparatus according to claim 17, wherein suction means for sucking the annular space is connected to the annular space.   The substrate processing apparatus according to any one of claims 1 to 20, wherein a step for forming a gas reservoir is formed on the outer peripheral portion of the support surface of the stage in cooperation with the outer peripheral portion of the base material. . The substrate processing apparatus according to any one of claims 1 to 21 , wherein an output wavelength of the radiant heater corresponds to an absorption wavelength of the unnecessary material. It is a method of removing unnecessary materials coated on the outer periphery of a substrate,
Support the substrate on the stage,
A heat beam from a radiant heater is locally applied to the processing position on the outer peripheral portion of the substrate to locally heat the processing position, and the light is placed in the vicinity of the processing position that is locally heated. A base material processing method, characterized in that a reactive gas for removing unnecessary substances is blown out from a blow-out port of a blow-out port forming member made of a material toward the processing position. When viewed from a direction orthogonal to the base material, the reactive gas is blown out from the outlet at a position substantially along the tangent line at the processing position of the base material, and downstream of the processing position in the blowing direction. 24. The substrate processing method according to claim 23, wherein suction is performed from a suction port of an exhaust nozzle disposed on the side so as to face the blowout port .

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