JP3916340B2 - Thin film forming apparatus and method of manufacturing contact jig thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a method of manufacturing a thin film forming apparatus represented by a copper film forming apparatus and a contact jig thereof.
[0002]
[Prior art]
Aluminum is generally used as a conductive material for wiring patterns of silicon wafers used in semiconductor integrated circuits. However, this aluminum has an electrical conductivity of about 2/3 that of copper and a high resistance (3 to 3.3 μΩ · cm), which hinders the speeding up of the IC. Therefore, in recent years, a wiring pattern using copper (1.7 to 1.9 μΩ · cm) has been intensively studied in order to reduce the wiring impedance and increase the speed of the IC. When forming this copper wiring pattern, a thin conductive film is formed on the surface of the silicon wafer as the first step, and then, as a second step, electrolytic plating (electroplating) is performed using the conductive film as a cathode. By forming an electrolytic plating layer, a predetermined copper wiring pattern can be formed on the silicon wafer.
[0003]
The conductive film is also referred to as a plating base, and is formed by a dry plating method such as a vapor deposition method, an ion plating method, or a sputtering method at a location where a copper wiring pattern is to be formed on the silicon wafer surface. This conductive film is usually formed in the range of 0.2 μm to 1 μm and electroplated. This is because the film formation speed and mass productivity are taken into consideration, and the required time for forming the thick film is shortened as much as possible, and the required range for the film thickness that can form the electrolytic plating layer is shown. It is.
[0004]
Since many products are simultaneously formed on the surface of the silicon wafer, it is required to form a film having a uniform thickness on the entire surface of the silicon wafer through the first and second steps. According to the dry plating method, since the vapor pressure of copper in the plating chamber is uniform within the surface of the silicon wafer, there is almost no variation in the thickness of the conductive film, and even when managing the thickness of the conductive film, the sputtering target, Alternatively, the voltage or the like may be adjusted as appropriate. On the other hand, in the electroplating method, an electrolytic plating layer having a uniform thickness cannot be obtained unless the current density of the pattern to be plated is controlled uniformly, as well as the temperature and concentration of the chemical solution.
[0005]
The conductive film, i.e., the plating base, is formed by the above method, and is characterized by being extremely thin and having high resistance. Therefore, when the power is supplied from only one place, the current density cannot be made uniform when the electrolytic plating layer is formed, and an electrolytic plating layer having a uniform thickness cannot be obtained at all. In order to solve such problems, special plating jigs such as power feeding from a plurality of locations on the outer peripheral edge of the conductive film of the silicon wafer have been developed and used. This plating jig supplies power by the following method as disclosed in JP-A-5-36698.
[0006]
In this publication, a plurality of electrodes are embedded in a substantially ring-shaped jig at equal intervals, and the outer peripheral edge portion of the conductive film formed on the surface of the silicon wafer is brought into contact with the plurality of electrodes. The difference in current density in the silicon wafer surface is obtained by electroplating the conductive film, which is the cathode, with a plurality of contact-corresponding portions in the part as electrode portions and applying an appropriate potential difference between the plurality of electrode portions and the electrodes. A plating jig that significantly reduces the variation in the thickness of the copper plating pattern while suppressing the above is disclosed. According to this plating jig, it is possible to suppress a difference in current density to a smaller extent than when power is supplied from one place. However, in this jig, a difference occurs in the current density at a position away from the electrode portion of the conductive film, which causes a variation in the thickness of the copper plating pattern.
[0007]
In the same publication, an electrode having the same shape is provided on a substantially ring-shaped jig, and the outer peripheral edge of the conductive film formed on the surface of the silicon wafer is mounted and supported on the flat surface of the electrode. An example is disclosed in which the outer peripheral edge of the conductive film is used as an electrode portion and electrolytic plating is performed by applying a potential difference between the electrode portion and the electrode. However, in this example, it is very difficult to form a flat surface on the electrode. Moreover, when improving the contact property with respect to the outer periphery part of an electrically conductive film by using an electrode as a thin film, an electrode is easy to deform | transform easily and you must pay careful attention for deformation prevention. Further, when the electrode is deformed, the contact portion becomes non-uniform, so that a difference occurs in the current density and a variation in the thickness of the copper plating pattern occurs.
[0008]
On the other hand, in Japanese Patent Laid-Open No. 58-181898, a ring-shaped elastic body is formed using silicone rubber and the like, and an electrode of the same shape made of copper is provided around the elastic body. The outer peripheral edge of the conductive film deposited on the surface is brought into contact with the outer peripheral edge of the conductive film as an electrode part, and an appropriate potential difference is applied between the electrode part and the electrode to electrolyze the conductive film as the cathode. A power supply device for plating is disclosed. However, in this power feeding device, the electrode and the outer peripheral edge of the conductive film are in point contact not only in the cross-sectional direction of the electrode but also in the line direction. Differences occur and variations in the copper plating pattern thickness occur.
[0009]
[Problems to be solved by the invention]
Since conventional plating jigs and power feeding devices are configured as described above, there is a problem in that a difference occurs in current density and variation in copper plating pattern thickness increases.
[0010]
The present invention has been made in view of the above problems, and it is an object of the present invention to provide a thin film forming apparatus and a method for manufacturing a contact jig thereof that can suppress and prevent a difference in current density and reduce variations in plating pattern thickness. It is said.
[0011]
[Means for Solving the Problems]
In the invention of claim 1, in order to achieve the above-mentioned object, the outer peripheral portion of the wafer is brought into contact with an endless contact jig, and the surface of this wafer is electrolytically plated to form a thin film,
The contact jig includes an endless electrode substrate, an endless elastic pillow body provided on the electrode substrate, and at least one end joined on the electrode substrate so as to be arranged in the circumferential direction of the elastic pillow body. A plurality of conductive wires supported at least from the lower part of either the inner or outer portion of the elastic pillow body to the vicinity of the upper portion of the elastic pillow body, and the elastic pillow body and the plurality of conductive wire materials are coated to cover the wafer. And an endless sealing elastic body that supports the outer peripheral portion of the surface and exposes the upper portion of each conductive wire to be in contact with the outer peripheral portion of the surface of the wafer.
[0012]
In addition, both ends of the plurality of conductive wires are joined to the electrode substrate, the elastic pillows are straddled over the conductive wires, and the upper portions of the conductive wires are protruded from the surface of the seal elastic body. Can do.
Further, one end portions of the plurality of conductive wires can be joined to the electrode substrate, and the upper end portion of the other end can be protruded from the surface of the seal elastic body.
[0013]
According to a fourth aspect of the present invention, in order to achieve the above object, the outer peripheral portion of the wafer having a thin film formed on the surface by electrolytic plating is supported by a seal elastic body, and the seal is formed on the outer peripheral portion of the wafer. A method of manufacturing a contact jig of a thin film forming apparatus for contacting upper portions of a plurality of conductive wires protruding from the surface of an elastic body,
A process of casting and curing a molding material on an endless electrode substrate to form an elastic pillow body having a substantially semicircular cross section in an endless manner;
At least one end of each of the plurality of conductive wire members is joined to the electrode substrate and arranged in the circumferential direction of the elastic pillow body, and each of the conductive wire members is provided from at least the lower part of the elastic pillow body inside or outside the elastic pillow body. Extending to near the top of the
The molding material is cast-cured on the electrode substrate to form the seal elastic body that covers the elastic pillow body and the plurality of conductive wires in an endless manner, and the upper portion of each conductive wire is formed from the surface of the seal elastic body. And a step of exposing.
In addition, it is good to join at least one end part of each said conductive wire on the said electrode board | substrate using the method of either an ultrasonic wire bonding method or a resistance welding method.
[0014]
Here, the wafer in the claims includes a Si wafer, a GaP wafer, or various types of wafers. In addition, there are various types of electrode substrates such as a printed wiring substrate, but almost all substrates used in this field are included. In addition, the elastic pillow body and the seal elastic body have a JIS hardness A20 ° to 60 °, preferably a JIS hardness A20 ° to 40 °, and are excellent in watertight function, elastic function, and / or compression set characteristics. It can be molded using rubber or the like. The substantially semicircular cross section includes a semicircular cross section, a semicircular cross section, a semielliptical cross section, a semielliptical cross section, or a similar shape.
[0015]
The arrangement pitch of the plurality of conductive wires is 0.03 mm to 1 mm, preferably 0.03 mm to 0.05 mm. The plurality of conductive wires may be arranged at a constant pitch in the circumferential direction of the elastic pillow body to improve current density uniformity or not. Examples of each conductive wire include a punched and slender conductive plate and a wire. The ultrasonic wire bonding method includes an ultrasonic wire bonding method, an ultrasonic combined thermocompression wire bonding method, and an ultrasonic heating method, and any bonding method may be used. Furthermore, the thin film forming apparatus may be a copper plating apparatus or an apparatus for forming another metal thin film.
[0016]
According to the first or fourth aspect of the invention, the upper portions of the plurality of conductive wires arranged in the circumferential direction of the elastic pillow body are exposed from the surface of the seal elastic body, and the upper portions of the plurality of conductive wire materials are the surface of the wafer. It contacts the outer periphery, and equalizes the current density during electrolytic plating. At this time, the elastic pillow body functions as a guide and reinforces the elastic force of the conductive wire. In addition, when a highly rigid conductive wire is used, there is a risk of difficulty in controlling the height accuracy and securing the posture, but the elastic pillow functions as a guide, so the height accuracy can be controlled easily. And the attitude of the conductive wire can be maintained in a predetermined attitude. In addition, since the seal elastic body protects the elastic pillow body and the portions other than the upper part of the plurality of conductive wires, the contact resistance between the outer peripheral portion of the wafer and the contact jig varies with the contact between the plating solution and the conductive wires. Can be suppressed or prevented. Furthermore, the seal elastic body assists the elasticity of the conductive wire, and gives a restoring force to the conductive wire so that the contact pressure can be maintained.
[0017]
Further, according to the invention described in claim 2, since both ends of the plurality of conductive wires straddling the elastic pillow body are respectively joined on the electrode substrate, the conductive wires can be formed in a shape having spring elasticity, and elastic. The pillow can support the conductive wire in a stable, elastic and effective manner. Further, it is possible to suppress or prevent each conductive wire from unnecessarily moving or being displaced in the circumferential direction of the elastic pillow body.
According to the invention described in claim 3, since only one end of each of the plurality of conductive wires is joined onto the electrode substrate and the conductive wire is wound around the elastic pillow body, the conductive wire is processed into a shape having spring elasticity. The conductive pillow can be stably, elastically and effectively held in the elastic pillow body. Moreover, it becomes possible to reduce the usage-amount of a conductive wire compared with the case where the both ends of a conductive wire are each joined.
[0018]
Furthermore, according to the fifth aspect of the invention, when the ultrasonic wire bonding method is used, the wires are bonded at room temperature or low temperature, the bonding area is reduced, or a high-density connection pitch is supported. be able to.
In addition, when the resistance welding method is selected, a large current is passed through the welding point, melting is caused by the electric resistance heat (joule heat) generated here, and joining is performed by applying pressure. Even when the ultrasonic wire bonding method cannot be used for reasons such as high temperature and hardness, it is possible to stably and firmly bond at least one end of the conductive wire on the electrode substrate.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.
As shown in FIGS. 1 and 2, the thin film forming apparatus according to the present embodiment is provided around the plating chamber 1, a holding lid 4 for the plating chamber, and the upper opening of the plating chamber 1. An insoluble contact jig 7 for mounting and supporting the outer peripheral edge P of the thin seed layer C formed on the entire surface is provided, and the seed layer C of the silicon wafer W is electrolytically plated by contact plating, that is, bladder plating. Thus, a wiring pattern made of copper is formed.
[0020]
As shown in FIG. 1, the plating chamber 1 is formed into a bottomed cylindrical shape by combining, for example, PVC, PP, FRP, stainless steel, or titanium and a reinforcing metal member, and includes a chemical liquid containing a plurality of chemicals. 2 is stored. Inside the plating chamber 1, an injection mechanism (not shown) composed of a pump or the like located at the bottom and a copper anode (not shown) are respectively disposed. An anode and a diffuser (not shown) are arranged from the injection mechanism. The chemical liquid 2 functions so as to come into jet contact at a constant speed with the seed layer C of the silicon wafer W that passes through and sequentially faces (see the arrow in FIG. 1). A ring-shaped support flange 3 is horizontally provided around the inner periphery of the upper opening of the plating chamber 1, and a ring-shaped contact jig 7 is installed on the support flange 3. The presser lid 4 includes a window 5 having a diameter smaller than that of the silicon wafer W, and is detachably attached to the upper portion of the opening of the plating chamber 1 via a plurality of fasteners 6 so as to contact the silicon wafer W directly below the contact jig. 7 and the rattling of the silicon wafer W is prevented.
[0021]
As shown in FIGS. 1 and 2, the contact jig 7 includes a ring-shaped electrode substrate 8 mounted on the support flange 3 of the plating chamber 1. An elastic pillow body 9 and a plurality of pillows 9 are mounted on the electrode substrate 8. The wire 10 and the seal elastic body 11 are disposed in combination. The electrode substrate 8 is formed of a printed wiring board in which a copper foil is bonded to an insulating resin substrate, and platinum is plated on a portion that may come into contact with the chemical liquid 2 from the viewpoint of preventing impurities from being mixed. A connecting portion (not shown) protrudes radially outward from the outer peripheral portion of the electrode substrate 8, and this connecting portion is connected to a single plating DC power source (for example, a large current low voltage rectifier or a silicon rectifier). Connected via connector. The elastic pillow body 9 is formed into a ring shape with a semicircular cross section using a fluoro rubber having a JIS hardness of A20 ° to 40 °, and is installed on the electrode substrate 8.
[0022]
As shown in FIG. 2, the plurality of wires 10 are made of a gold wire having elasticity, and are excellent in conductivity after both ends are electrically ultrasonically bonded to inner and outer ends on the electrode substrate 8. Platinum is plated. The plurality of wires 10 are juxtaposed at a constant pitch of 0.03 mm to 0.5 mm in the circumferential direction of the elastic pillow body 9, and are elastically supported in a wound contact state on the surface across the elastic pillow body 9. Further, the seal elastic body 11 is formed in a substantially inverted concave shape using a fluoro rubber having a JIS hardness A of 20 ° to 40 °, and is placed on the electrode substrate 8 so as not to be attached to the elastic pillow body 9 and the plurality of wires 10. Is encapsulated from above. Then, only the curved upper portion 10a of each wire 10 is slightly exposed from the flat surface 11a, and the curved upper portion 10a, in other words, the cathode electrode portion is protruded and contacted with the outer peripheral edge portion P of the seed layer C of the silicon wafer W. It works as follows.
[0023]
Further, the silicon wafer W is formed by sequentially forming an insulating film on the surface, forming a wiring pattern by etching the insulating film, removing a natural oxide film by pre-cleaning, and forming a copper barrier layer by Ta and TaN. A copper seed layer C is formed on the layer. This copper seed layer C provides a good current path and promotes subsequent copper grain growth.
[0024]
Next, a method for manufacturing the contact jig 7 will be described with reference to FIGS. 3 (a), 3 (b), and 3 (c).
First, marking lines (not shown) are drawn at both the inner and outer ends on the electrode substrate 8, and liquid fluororubber is cast between the marking lines through a mold (not shown) to be heat-cured. The elastic pillow body 9 is protruded into a ring shape (see FIG. 3 (a)). Even if there are variations in wettability, surface tension, etc. between the electrode substrate 8 and the fluororubber, each marking line prevents and suppresses the variation in the width due to the dripping of the fluororubber. Is stable.
[0025]
Next, both end portions of the plurality of wires 10 are ultrasonically wire-bonded to both the inner and outer end portions on the electrode substrate 8 and sequentially arranged at a constant pitch in the circumferential direction of the elastic pillow body 9. The wires 10 are elastically supported on the surface in a wound contact state, and a plurality of wires 10 are plated with platinum together with the electrode substrate 8 (see FIG. 3B). Then, a liquid elastic rubber is cast on the electrode substrate 8 through a mold (not shown) and is heat-cured, and the elastic elastic body 9 and the non-upper portions of the platinum-plated wires 10 are encapsulated from above. 11 is formed in a ring shape, and the curved upper portion 10a of each wire 10 is slightly exposed from the surface 11a of the seal elastic body 11, whereby the contact jig 7 having a simple configuration can be manufactured (FIG. 3 ( c)). The contact jig 7 manufactured in this way is mounted on the support flange 3 of the plating chamber 1 and connected to a DC power supply for plating via a connector.
[0026]
In the above configuration, when a wiring pattern made of copper is formed, the outer peripheral edge P of the seed layer C of the silicon wafer W is mounted and supported on the flat seal elastic body 11 of the contact jig 7, and the opening of the plating chamber 1 is formed. The presser lid 4 is covered on the upper part via the fastener 6, and the silicon wafer W is pressed against the contact jig 7 in close contact. Then, if the thin film forming apparatus is operated, a potential difference is applied between the anode of the silicon wafer W and the anode, and the chemical liquid 2 is brought into contact with the seed layer C by an injection mechanism, the seed layer of the silicon wafer W is obtained by a plating reaction. An electrolytic plating layer is formed on C. Then, a predetermined copper wiring pattern can be formed on the silicon wafer W by performing a planarization process by CMP or the like.
[0027]
According to the above configuration, since the plurality of wires 10 aligned at a constant pitch in the circumferential direction of the elastic pillow body 9 are in contact with the outer peripheral edge portion P of the seed layer C, it is extremely effective to suppress and prevent the difference in current density from occurring. And there is no variation in the thickness of the copper plating pattern. Further, since the number of contact points between the contact jig 7 and the outer peripheral edge P of the seed layer C can be increased in the circumferential direction of the contact jig 7, a difference occurs in the current density, and the copper plating pattern thickness varies. It is possible to effectively prevent the occurrence of. Further, since the conductor resistance of each wire 10 is low, it is possible to very effectively suppress and prevent a difference in current density.
[0028]
In addition, since each wire 10 is plated with platinum having a higher rigidity than gold, it does not easily deform, and there is no need to pay close attention to prevent deformation. In particular, compared to the case where the gold wire is used as it is, it is possible to suppress or prevent the possibility of contamination of the plating. In addition, when using hard platinum, it is difficult to control the accuracy of the height and to secure the loop shape. However, since the elastic pillow body 9 functions as a guide and a base, the accuracy of the loop height can be controlled very easily. And a predetermined loop shape can be easily ensured. Further, since the elastic pillow body 9 also reinforces the elastic force of the wire 10, the wire 10 is not buried in the pillow body 9, and stable connection can be greatly expected even after repeated use. In addition, since the seal elastic body 11 assists the spring elasticity of the wire 10 and gives a restoring force to the wire 10 so that the contact pressure can be maintained, stable connection can be achieved even when used repeatedly.
[0029]
Further, since the seal elastic body 11 protects the elastic pillow body 9 and the non-upper portions of the plurality of platinum-plated wires 10, contact with the outer peripheral edge P of the seed layer C and contact treatment with the contact between the chemical liquid 2 and the wire 10 is achieved. There is no variation in the contact resistance with the tool 7, and the current density can be made extremely uniform. Moreover, since the sealing elastic body 11 is comprised by a shaping | molding method, the surface 11a of the sealing elastic body 11 can be planarized easily. In addition, since the elastic pillow body 9 and the seal elastic body 11 have a low hardness of 20 ° to 40 °, respectively, the pressing force for maintaining the watertight function is prevented from being a stress on the electrode substrate 8 and the silicon wafer W. It becomes possible to do.
[0030]
Further, since the elastic pillow body 9 and the seal elastic body 11 are respectively formed of fluororubber, an effect excellent in heat resistance, oil resistance, chemical resistance, solvent resistance, weather resistance, and / or ozone resistance is obtained. I can expect. In this regard, when molding with silicone rubber, low molecules bleed as oligomers even after vulcanization, which may cause problems during the plating operation or cause problems in subsequent processes. However, since it molds with fluororubber, such a problem can be solved. Furthermore, since there are no corners on the surface of the elastic pillow body 9, it can be expected to prevent the stress on the plurality of wires 10 from being suppressed.
[0031]
Next, FIG. 4 shows a second embodiment of the present invention. In this case, one end portion of a plurality of wires 10 is ultrasonically wire-bonded to the outer end portion on the electrode substrate 8 and the other end portion is attached. The upper end portion 10b is extended to the upper surface of the elastic pillow body 9, and the upper end portion 10b of each wire 10, that is, the cathode electrode portion is slightly exposed from the surface 11a of the seal elastic body 11, so that the seed layer C of the silicon wafer W is formed. The outer peripheral edge P is projected and contacted. The other parts are the same as those in the above embodiment, and the description thereof is omitted.
In this embodiment, the same effect as the above embodiment can be expected, and since only one end portion of the wire 10 is subjected to ultrasonic wire bonding, it is obvious that the bonding work time can be shortened.
[0032]
Next, FIG. 5 shows a third embodiment of the present invention. In this case, one end of a plurality of wires 10 is ultrasonically bonded to both inner and outer end portions on the electrode substrate 8, respectively. The wires 10 are arranged in a zigzag pattern in the circumferential direction, the upper end portion 10 b of the other end of each wire 10 is extended near the upper surface of the elastic pillow body 9, and the upper end portion 10 b of each wire 10 is connected to the seal elastic body 11. It is slightly exposed from the surface 11a (not shown, but the same as in FIG. 4) so as to protrude and contact the outer peripheral edge P of the seed layer C of the silicon wafer W. The other parts are the same as those in the above embodiment, and the description thereof is omitted.
[0033]
In the present embodiment, the same effect as the above embodiment can be expected, and the amount of the wire 10 used can be greatly reduced, and the contact area in the inner and outer end portions of the electrode substrate 8 can be increased. It is obvious that it can be done.
[0034]
Next, FIG. 6 shows a fourth embodiment of the present invention. In this case, an elongated platinum conductive plate 12 is used in place of the wire 10 in the third embodiment, and an ultrasonic wire is used. The resistance welding method is adopted instead of the bonding method. The other parts are the same as those in the above embodiment, and the description thereof is omitted.
In this embodiment, the same effect as that of the above embodiment can be expected, and the contact area between the outer peripheral edge P of the seed layer C and the contact jig 7 can be greatly increased in the circumferential direction of the contact jig 7. Can be planned. Further, the conductive wire has a melting point of 1768 ° C., a boiling point of 3827 ° C., a specific gravity of 21.45, and a specific resistance of 10.6 × 10. ^-6 Ω · cm (0 ° C), Mohs hardness 4.3, harder than silver, and made of chemically stable platinum. There is little possibility of contamination with impurities.
[0035]
Next, FIG. 7 shows a fifth embodiment of the present invention. In this case, all or a part of the plurality of conductive plates 12 according to the fourth embodiment are bifurcated. The upper end portion 12a, that is, the cathode electrode portion is slightly exposed from the surface 11a of the seal elastic body 11 (not shown, but the same as in FIG. 4), and the outer peripheral edge of the seed layer C of the silicon wafer W is formed. The part P is projected and contacted. The other parts are the same as those in the above embodiment, and the description thereof is omitted.
Also in this embodiment, the same effect as the above embodiment can be expected, and the contact pressure between the outer peripheral edge P of the seed layer C and the contact jig 7 is increased, and the stability and the flexibility of the upper edge portion are improved. It is possible to remarkably improve and to make contact with the contacted part even more uniformly.
[0036]
In the above embodiment, the plating chamber 1 of FIG. 1 is simply shown, but the configuration of the plating chamber 1 can be changed as appropriate. For example, the supporting flange 3 can be formed in a substantially mortar shape in cross section, and a wafer such as a silicon wafer W can be mounted and supported on the inner peripheral edge of the lower portion of the opening. The plating chamber 1 can be appropriately provided with a heating device, a cooling device, a filtration device, a stirring device, and / or an exhaust device. Further, a transfer device or the like that automatically sets the silicon wafer W in the plating chamber 1 can be provided. Further, a plurality of connecting portions may be protruded from the outer peripheral portion of the electrode substrate 8 in accordance with the uniformity of the current density and the like, and each connecting portion may be connected to a plating DC power source. The DC power source for plating may be a common power source or a plurality of dedicated power sources.
[0037]
Further, the elastic pillow body 9 can be formed into a square cross section, a polygonal cross section, or a substantially semi-oval cross section. Further, the upper portion of the wire 10 may be extended near the vicinity of the upper surface of the elastic pillow body 9. Further, the wire 10 and the conductive plate 12 can be used in combination. Further, the bifurcated upper end portion 12a of the conductive plate 12 can be slightly inclined upward. Further, the upper end portion 12a of each conductive plate 12 may be appropriately branched into three or the like. Further, if the seal elastic body 11 is made of fluoro rubber having a hardness of 20 ° to 60 ° and a plurality of wires 10 are arranged at a small pitch of 0.03 mm to 1 mm from existing data, empirical rules, and experimental results, the seed layer The contact points of the plurality of wires 10 with respect to the outer peripheral edge P of C are increased uniformly, and the uniformity of current density is improved.
[0038]
【Example】
Examples of the method for manufacturing the contact jig 7 according to the present invention will be described below. Example 1
First, an electrode substrate 8, a casting mold, SIFEL (Fluorine rubber manufactured by Shin-Etsu Chemical Co., Ltd.), and an ultrasonic wire bonder were prepared. The electrode substrate 8 is made of a copper-clad printed wiring board (glass / epoxy base material) patterned so that a single connection portion protrudes from the outer peripheral portion thereof. The pattern is gold plated on a nickel base. The wire 10 used in the ultrasonic wire bonder was a 50 μm gold wire.
[0039]
First, SIFEL was cast on the electrode substrate 8 through a mold and cured by heating, and an elastic pillow 9 having a semicircular cross section (height: 1.0 mm, width: 1.0 mm) was formed into a ring shape. Next, both ends of the wire 10 are wire-bonded to the inner and outer ends on the electrode substrate 8 by an ultrasonic-heating method, and are arranged in parallel at a constant pitch of 0.5 mm in the circumferential direction of the elastic pillow body 9. The elastic pillow body 9 was straddled on 10 and each wire 10 was elastically supported on the surface in a wound contact state, and the electrode pattern of the electrode substrate 8 and the plurality of wires 10 were plated with platinum.
[0040]
After that, SIFEL is cast on the electrode substrate 8 through a mold and cured by heating, and the elastic elastic body 9 and the seal elastic body 11 encapsulating the non-upper portions of the plurality of platinum-plated wires 10 from above are formed in a ring shape. The curved upper portion 10a of each wire 10 was slightly exposed from the surface 11a of the seal elastic body 11, and the contact jig 7 was manufactured.
[0041]
Example 2
First, the electrode substrate 8 was made of a 4-2 alloy plate having a thickness of 0.3 mm, and the 4-2 alloy plate was subjected to a gold plating process. SIFEL was cast on this electrode substrate 8 through a mold and heat-cured, and an elastic pillow 9 having a semicircular cross section (height: 1.0 mm, width: 1.0 mm) was protruded into a ring shape. Next, both ends of the wire 10 are wire-bonded to the inner and outer ends on the electrode substrate 8 by an ultrasonic-heating method, and are arranged in parallel at a constant pitch of 0.5 mm in the circumferential direction of the elastic pillow body 9. 10, the elastic pillow body 9 was straddled and each wire 10 was elastically supported on the surface in a wound contact state, and the electrode substrate 8 and the plurality of wires 10 were plated with platinum.
[0042]
Then, SIFEL is cast on the electrode substrate 8 through a mold and cured by heating. The elastic pillow 9, the plurality of platinum-plated wires 10, and the chemical liquid 2 on the inner peripheral side of the plurality of wires 10 are formed. The seal elastic body 11 encapsulating the contacted portion from above was formed into a ring shape, and the upper portion of each conductive wire was slightly exposed from the surface 11a of the seal elastic body 11, whereby the contact jig 7 was manufactured.
[0043]
Example 3
First, the electrode substrate 8 is made of a SUS304 plate having a thickness of 0.3 mm, a plurality of marking lines are drawn on the SUS304 plate so as to have a spacing of 1.0 mm, and a plurality of marking lines are formed so as not to leach outside each marking line. SIFEL was cast between the marking lines through a mold and cured by heating, and an elastic pillow 9 having a semicircular cross section (height: 1.0 mm, width: 1.0 mm) was formed into a ring shape.
[0044]
Next, resistance welding is performed on the elastic pillow body 9 at a position in contact with the electrode substrate 8 so as to cross the platinum conductive plate 12 having a thickness of 0.2 mm and a width of 1.0 mm. A cathode electrode portion was formed by sequentially arranging them at a pitch of 0 mm. Then, SIFEL is cast on the electrode substrate 8 through a mold and heated and cured, and the elastic seal body 9 and the sealing elastic body 11 encapsulating the non-upper portions of the plurality of conductive plates 12 from above are formed into a ring shape. The contact jig 7 was manufactured by slightly exposing the upper end 12a of each conductive plate 12 from the surface 11a of the seal elastic body 11.
[0045]
Example 4
First, the electrode substrate 8 is manufactured from a SUS304 plate having a thickness of 0.3 mm, a plurality of marking lines are drawn on the SUS304 plate so as to have a gap of 1.0 mm, and a plurality of marking lines are prevented from leaching outside the marking lines. SIFEL was cast between the marking lines through a mold and cured by heating, and an elastic pillow 9 having a semicircular cross section (height: 1.0 mm, width: 1.0 mm) was formed into a ring shape.
[0046]
Next, resistance welding is performed at a position where the elastic pillow body 9 is in contact with the electrode along the platinum conductive plate 12 having a thickness of 0.2 mm, a width of 1.0 mm, and an upper end portion 12a that is bifurcated. The conductive plates 12 were successively arranged at a pitch of 2.0 mm to form a cathode electrode portion. After that, SIFEL is cast on the electrode substrate 8 through a mold and heat-cured to seal the elastic pillow body 9 and the non-upper portions of the plurality of conductive plates 12 having the bifurcated upper ends 12a from above. The body 11 was molded into a ring shape, and the upper end portion 12a of each conductive plate 12 was slightly exposed from the surface 11a of the seal elastic body 11 to manufacture the contact jig 7.
[0047]
As a result of forming the electrolytic plating layer formed using each of the contact jigs 7, the thickness variation of the electrolytic plating layer was 0.2 μm or less at any location on the surface of the silicon wafer W. . Furthermore, even if the contact jig 7 is used 10,000 times, the initial characteristics can be maintained, and the variation in the thickness of the electrolytic plating layer can be reduced to 0. 0 at any location on the surface of the silicon wafer W. It was 2 μm or less.
[0048]
【The invention's effect】
As described above, according to the present invention, it is possible to suppress or prevent the difference in current density flowing through the wafer and to reduce the variation in the thickness of the plating pattern.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional explanatory view showing an embodiment of a thin film forming apparatus according to the present invention.
FIG. 2 is a schematic cross-sectional explanatory view showing an embodiment of a method for manufacturing a contact jig of a thin film forming apparatus according to the present invention.
FIG. 3 is a cross-sectional explanatory view showing an embodiment of a method for manufacturing a contact jig of a thin film forming apparatus according to the present invention, wherein FIG. (b) is a cross-sectional explanatory view showing a state in which the wire is elastically supported on the surface of the elastic pillow body in a wound state. It is sectional explanatory drawing which shows the state which shape | molded the elastic body.
FIG. 4 is a cross-sectional explanatory view showing a second embodiment in the method for manufacturing a contact jig of the thin film forming apparatus according to the present invention.
FIG. 5 is a partial perspective explanatory view showing a third embodiment of the method for manufacturing a contact jig of the thin film forming apparatus according to the present invention.
FIG. 6 is a partial perspective explanatory view showing a fourth embodiment in the method for manufacturing a contact jig of the thin film forming apparatus according to the present invention.
FIG. 7 is a partial perspective explanatory view showing a fifth embodiment in the method for manufacturing a contact jig of the thin film forming apparatus according to the present invention.
[Explanation of symbols]
1 Plating chamber
2 Chemical liquid
3 Support flange
4 Holding lid
7 Contact jig
8 Electrode substrate
9 Elastic pillow body
10 wire (conductive wire)
10a Curved upper part (upper part)
10b Upper end
11 Seal elastic body
12 Conductive plate (conductive wire)
12a Upper end
C seed layer
P outer periphery (outer periphery)
W Silicon wafer (wafer)

Claims (5)

A thin film forming apparatus for forming a thin film by bringing the outer periphery of a wafer into contact with an endless contact jig and electrolytically plating the surface of the wafer.
The contact jig includes an endless electrode substrate, an endless elastic pillow body provided on the electrode substrate, and at least one end joined on the electrode substrate so as to be arranged in the circumferential direction of the elastic pillow body. A plurality of conductive wires supported at least from the lower part of either the inner or outer portion of the elastic pillow body to the vicinity of the upper portion of the elastic pillow body, and the elastic pillow body and the plurality of conductive wire materials are coated to cover the wafer. A thin film forming apparatus comprising: an endless seal elastic body that supports the outer peripheral portion of the surface and exposes the upper portion of each conductive wire to be in contact with the outer peripheral portion of the surface of the wafer. The both ends of the plurality of conductive wires are joined to the electrode substrate, the elastic pillows are straddled over the conductive wires, and the upper portions of the conductive wires are protruded from the surface of the seal elastic body. The thin film forming apparatus according to 1. The thin film forming apparatus according to claim 1, wherein one end portions of the plurality of conductive wires are joined to the electrode substrate, and an upper end portion of the other end is projected from the surface of the seal elastic body. A thin film in which a surface elastic part of a wafer on which a thin film is formed by electrolytic plating is supported on a surface by a seal elastic body, and upper portions of a plurality of conductive wires protruding from the surface of the seal elastic body are in contact with the surface outer peripheral part of the wafer A method of manufacturing a contact jig of a forming apparatus,
A process of casting and curing a molding material on an endless electrode substrate to form an elastic pillow body having a substantially semicircular cross section in an endless manner;
At least one end of each of the plurality of conductive wire members is joined to the electrode substrate and arranged in the circumferential direction of the elastic pillow body, and each of the conductive wire members is provided from at least the lower part of the elastic pillow body inside or outside the elastic pillow body. Extending to near the top of the
The molding material is cast-cured on the electrode substrate to form the seal elastic body that covers the elastic pillow body and the plurality of conductive wires in an endless manner, and the upper portion of each conductive wire is formed from the surface of the seal elastic body. A method for manufacturing a contact jig for a thin film forming apparatus. 5. The manufacturing method of a contact jig for a thin film forming apparatus according to claim 4, wherein at least one end of each conductive wire is joined to the electrode substrate using any one of an ultrasonic wire bonding method and a resistance welding method. Method.

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