JP3892749B2 - Substrate processing apparatus and substrate processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a substrate treatment for drying a semiconductor substrate, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, a substrate for an optical disk, etc. (hereinafter referred to as “substrate”) that has been cleaned with a treatment liquid such as pure water. Relates to the device.
[0002]
[Prior art]
In the substrate processing apparatus, surface treatment such as chemical treatment with various chemical solutions and cleaning treatment with pure water is sequentially performed. After finishing cleaning with pure water, a drying process is performed as a final process. As such a substrate drying process, for example, in a so-called single-wafer type substrate processing apparatus that performs substrate processing on each substrate one by one, the substrate is rotated at a high speed and moisture is applied to the substrate by the centrifugal force. Shaking-off drying (spin drying) is known.
[0003]
However, with this swing-off drying, with the recent complication of the semiconductor device structure, a drying defect called a watermark has become a problem. A watermark is a dry stain generated by the reaction of moisture adhering to the substrate surface with silicon, which is a material of the substrate, and oxygen in the air, and is more likely to occur as the time that moisture adheres to the substrate surface is longer.
[0004]
Therefore, a method of rotating and drying the substrate while spraying isopropyl alcohol (hereinafter also referred to as “IPA”), which is an organic solvent having a surface tension smaller than that of pure water and having a low latent heat of vaporization, has been proposed. Yes. Since IPA has a smaller surface tension and higher permeability than pure water, water droplets that have entered inside a fine pattern such as a trench structure formed on a substrate can be easily dried. In addition, IPA has a lower latent heat of vaporization and higher drying speed than pure water. For these reasons, in the drying method in which IPA is sprayed on the substrate while rotating the substrate, the water droplets on the substrate are shaken out while draining the water droplets that have entered the fine pattern on the substrate, so that moisture adheres to the substrate surface. The drying time can be reduced, generation of watermarks can be suppressed, and drying performance can be improved.
[0005]
[Problems to be solved by the invention]
However, a substance that has an impact on the environment, such as IPA, cannot be released to the outside as it is, and it is necessary to perform a predetermined drainage treatment to make it a harmless substance, which increases the cost of substrate processing. Problems arise. Further, when IPA is used, it is necessary to provide a special safety mechanism such as an explosion-proof structure, so that there is a problem that the substrate processing apparatus is increased in size and the manufacturing cost of the substrate processing apparatus is increased.
[0006]
In addition, with further miniaturization and complexity of semiconductors in recent years, even when IPA is used, it is sometimes difficult to drain water droplets that have entered the fine pattern.
[0007]
And the problem of the drying process using such IPA is a problem which occurs not only in the single wafer type substrate processing apparatus but also in the batch type substrate processing apparatus which performs substrate processing on a plurality of substrates at once. .
[0008]
Therefore, the present invention provides a substrate processing apparatus that dries while supplying a desiccant, and does not generate a watermark even if the substrate has a miniaturized / complex structure, and increases the cost required for the drying process. It is an object of the present invention to provide a substrate processing apparatus and a substrate processing method that can suppress the above-described problem.
[0009]
[Means for Solving the Problems]
  In order to solve the above-mentioned problem, the invention according to claim 1 has completed the cleaning treatment with the treatment liquid.pluralA substrate processing apparatus for drying a substrate,A treatment tank for storing a treatment liquid and immersing a plurality of substrates in the treatment liquid to perform a predetermined substrate treatment;,A lifting means for lifting a plurality of substrates after the substrate processing from the processing tank while holding the substrates in a substantially vertical posture;,It is provided above the processing tank and holds a plurality of substrates delivered from the lifting means in a substantially vertical posture.Holding means toA plurality of substrates are held around a rotation axis along a substantially horizontal direction and the holding means is rotated.A rotating unit; and a solvent supplying unit that rotates the substrate using the rotating unit and supplies a desiccant containing a fluorinated solvent as a main component to the substrate on which the processing liquid is adhered.
[0012]
  Claim 2The invention described inClaim 1The substrate processing apparatus according to claim 1, further comprising: a rotation speed control unit that reduces the rotation speed of the substrate by the rotation unit when supplying the desiccant from the solvent supply unit to the substrate held by the holding unit. It is characterized by that.
[0013]
  Claim 3The invention described in claim 1Or claim 24. The substrate processing apparatus according to claim 1, wherein the solvent supply unit supplies a vapor of a desiccant to the substrate.
[0014]
  Claim 4The invention described in claim 1 to claim 1Claim 3The substrate processing apparatus according to any one of the above, wherein the fluorine-based solvent is hydrofluoroether.
[0015]
  Claim 5The invention described in claim 1 to claim 1Claim 4The substrate processing apparatus according to any one of the above, wherein the desiccant is a solvent obtained by mixing the fluorine-based solvent and isopropyl alcohol.
[0016]
  Claim 6The invention described in the above is a substrate processing method for performing a drying process on a substrate that has been cleaned with a processing liquid,(a) A step of performing predetermined substrate processing by immersing a plurality of substrates in a processing solution stored in a processing tank; (b) Said process (a) A step of lifting the plurality of substrates that have been finished from the processing tank while being held in a substantially vertical posture by the lifting means;,(c) Said process (b) Delivering a plurality of substrates in a substantially vertical posture lifted by the lifting means to the holding means;,(d) Held by the holding meansRotating the substrate and supplying a desiccant containing a fluorinated solvent as the base material to the substrate to which the processing solution is attachedWorkAboutWhenIt is characterized by providing.
[0017]
  Claim 7The invention described in the above is a substrate processing apparatus for performing a drying process on a plurality of substrates that have been cleaned with a processing solution,A treatment tank for storing a treatment liquid and immersing a plurality of substrates in the treatment liquid to perform a predetermined substrate treatment;,A lifting means for lifting a plurality of substrates after the substrate processing from the processing tank while holding the substrates in a substantially vertical posture;,It is provided above the processing tank and holds a plurality of substrates delivered from the lifting means in a substantially vertical posture.Holding means toA plurality of substrates are held around a rotation axis along a substantially horizontal direction and the holding means is rotated.Rotating means and solvent supply means for rotating a substrate using the rotating means and supplying a desiccant containing a silicone-based solvent as a main agent to the substrate on which the processing liquid is adhered.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0019]
<1. First Embodiment>
(1) Configuration of substrate processing equipment
First, a first embodiment of the present invention will be described. 1 is a front view of a substrate processing apparatus 100 according to the first embodiment of the present invention, FIG. 2 is a side view of the substrate processing apparatus 100 shown in FIG. 1, FIG. 3 is a substrate processing apparatus 100 shown in FIG. The perspective view of the rotor 30 which is a component of is shown, respectively. 1 and the subsequent drawings are attached with an XYZ orthogonal coordinate system in which the Z-axis direction is the vertical direction and the XY plane is the horizontal plane, as necessary, in order to clarify the directional relationship.
[0020]
The substrate processing apparatus 100 according to the first embodiment is a so-called batch-type substrate processing apparatus, and can perform a plurality of substrate processing at a time, so that the throughput of the substrate processing can be improved. As shown in FIG. 1, the substrate processing apparatus 100 holds a plurality of substrates W in a substantially vertical posture in a processing tank 10 that stores a chemical solution such as hydrofluoric acid or pure water (hereinafter also referred to as “processing solution”). Then, the substrate is immersed and subjected to predetermined substrate processing, and mainly includes a container 1, a processing tank 10, a lifter 20, and a rotor 30.
[0021]
The container 1 is a housing that accommodates the processing tank 10, the lifter 20, the rotor 30, the nitrogen gas discharge nozzle 40, the desiccant discharge nozzle 50, the pure water discharge nozzle 60, and the like therein. The upper part of the container 1 can be opened and closed by a sliding opening / closing mechanism (not shown). When the upper part of the container 1 is opened, the substrate is carried in and out from the opened part. On the other hand, in a state where the upper portion of the container 1 is closed, the inside is set as a sealed space.
[0022]
The treatment tank 10 is a tank that stores a treatment liquid and sequentially performs surface treatment on a plurality of substrates, and is accommodated inside the container 1. Two processing liquid discharge nozzles (not shown) are arranged near the bottom of the processing tank 10, and by storing the processing liquid in the processing tank 10, predetermined substrate processing can be performed.
[0023]
The processing liquid is supplied from the bottom of the processing tank 10 and overflows from the upper end of the processing tank 10. For this reason, the recovery unit 12 is disposed at the upper end of the processing tank 10, and the drainage of the processing liquid overflowing from the upper part of the processing tank 10 is recovered by the recovery unit 12. The drainage liquid collected by the collection unit 12 and the drainage liquid discharged from the bottom of the processing tank 10 are drained outside the substrate processing apparatus 100 via a drainage pipe 15 connected to the bottom of the container 1. It is discharged to the liquid drain 16. In addition, a supply path and a discharge path for a liquid such as a processing liquid including the drain pipe 15 are configured by piping.
[0024]
As shown in FIG. 2, the lifter 20 includes a lifter arm 23, three holding bars 21 a, 21 b, 21 c, and a lift drive unit 22. The raising / lowering drive part 22 has a function which raises / lowers the lifter arm 23 along arrow AR2 (Z-axis direction) of FIG. In the lifter arm 23, three holding bars 21a, 21b, 21c are fixed so that the longitudinal direction thereof is substantially horizontal (Y-axis direction), and each of the three holding bars 21a, 21b, 21c is fixed. Are provided with a plurality of holding grooves arranged at a predetermined pitch so that the outer edge of the substrate W fits in and holds the substrate W in a substantially vertical posture. Each holding groove is a notch-shaped groove formed along the Y direction.
[0025]
With such a configuration, the lifter 20 immerses the plurality of substrates W arranged and held in parallel with each other by the three holding portions 21 a, 21 b, and 21 c in the processing liquid stored in the processing tank 10. It is moved up and down between the dipping position (solid line position in FIG. 1) and the lifting position above the processing tank 10 in the container 1 (dotted line position in FIG. 1). Further, the lifter 20 raises the substrate W to a delivery position (position where the substrate W is delivered to and from the transfer robot outside the apparatus) further above the lifting position.
[0026]
As shown in FIG. 3, the rotor 30 is provided at the above-described lifting position, and includes a motor 31, a rotating plate 32, and four holding arms 33. The holding arm 33 is a columnar member, and is attached to the rotating plate 32 so that the longitudinal direction thereof is along the Y-axis direction. The holding arm 33 is attached to the rotating plate 32 so as to be swingable around an axis that is parallel to the Y-axis direction and eccentric from the central axis. The four holding arms 33 are configured to swing in conjunction with each other by a link mechanism (not shown), and as shown by an arrow AR1 in FIG. 1, an edge portion of the substrate W located at the lifting position. Between the holding position (solid line position in FIG. 1) for holding and pressing the substrate W and the open position (dotted line position in FIG. 1) spaced from the edge of the substrate W to open the substrate W. Swing between.
[0027]
When the substrate W is transferred from the lifter 20 to the rotor 30, the lifter 20 rises and holds the substrate W in the lifting position. When the lifter 20 is raised and lowered, the holding arm 33 is positioned at the open position so that the substrate W can pass between the holding arms 33. In a state where the substrate W is held at the lifted position by the lifter 20, the holding arm 33 swings from the open position to the holding position and comes into contact with the edge of the substrate W to hold the substrate W. Even if the lifter 20 is lowered in this state, the state in which the substrate W is held by the rotor 30 by the holding arm 33 is maintained. Conversely, when the substrate W is transferred from the rotor 30 to the lifter 20, the lifter 20 is raised and the holding bars 21 a, 21 b, 21 c come into contact with the lower end portion of the substrate W held by the rotor 30. In this state, the holding arm 33 swings from the holding position to the open position and is separated from the edge of the substrate W, and the substrate W is held by the three holding portions 21a, 21b, and 21c of the lifter 20. Become.
[0028]
The central portion of the rotating plate 32 is fixed to the rotating shaft 34 of the motor 31. Thereby, the motor 31 can rotate the rotary plate 32, the four holding arms 33, and the plurality of substrates W held by them around the Y axis. That is, the rotor 30 holds a plurality of substrates W passed from the lifter 20 and rotates them all around the horizontal axis.
[0029]
Two nitrogen gas discharge nozzles 40, a desiccant discharge nozzle 50, and two pure water discharge nozzles 60 are provided in the container 1 in order from the top. As shown in FIG. 2, each of the nitrogen gas discharge nozzle 40, the desiccant discharge nozzle 50, and the pure water discharge nozzle 60 is a hollow tubular member that extends along the X direction, and is arranged at equal intervals in the X direction. A plurality of discharge holes 40a, 50a, 60a are provided. Each of the plurality of discharge ports 40a provided in the nitrogen gas discharge nozzle 40 and the plurality of discharge ports 50a provided in the desiccant discharge nozzle 50 has pure water so that the discharge direction is obliquely downward. Each of the plurality of discharge ports 60a provided in the discharge nozzle 60 is formed so that the discharge direction is substantially horizontal.
[0030]
Further, as shown in FIG. 1, the two nitrogen gas discharge nozzles 40 include a nitrogen gas supply source 43 and two desiccant discharge nozzles via a pipe 41 (41a, 41b, 41c, 41d) and a valve. 50 is a dry solvent supply source 56 via a pipe 51 (51a, 51b, 51c, 51d) and a valve 52, and a pure water discharge nozzle 60 is via a pipe 61 (61a, 61b, 61c, 61d) and a valve 62. The pure water supply source 63 is connected to each other. Therefore, by opening the valve 42, nitrogen gas is discharged from the nitrogen gas discharge nozzle 40 to form an atmosphere containing nitrogen gas in the container 1. In addition, the valve 52 is opened, and the drying solvent (HFE, which will be described later) is discharged from the desiccant discharge nozzle 50, and the pure water is discharged from the pure water discharge nozzle 60 by opening the valve 62. To the substrate W.
[0031]
Inside the container 1, a recovery unit 11 is provided below the processing tank 10, and the processing liquid discharged from the desiccant discharge nozzle 50 and the pure water discharge nozzle 60, and the processing tank 10 and the recovery unit 12. Used to recover the effluent. Similar to the processing tank 10 and the recovery unit 12, the recovery unit 11 is connected to a drainage pipe 15 at the bottom of the container 1, and the drainage recovered by the recovery unit 11 is discharged from the substrate processing apparatus 100. It is discharged to the liquid drain 16.
[0032]
The atmosphere in the container 1 is exhausted to an exhaust drain 18 outside the substrate processing apparatus 100 through an exhaust pipe 17 connected to the container 1. Therefore, the pressure in the container 1 is kept constant.
[0033]
The control unit 70 includes a memory 71 that stores programs, variables, and the like, and a CPU 72 that executes control according to the programs stored in the memory 71. The CPU 72 performs lifting / lowering control of the lifter 20, rotation control of the rotor 30, opening / closing control of each valve, and the like at predetermined timings according to a program stored in the memory 71.
[0034]
(2) Substrate drying process sequence
Here, a substrate drying process sequence performed by the substrate processing apparatus 100 according to the first embodiment will be described. FIG. 4 shows the open / closed state of the valves 40, 50, 60 from the time t 0 when the plurality of substrates W that have been subjected to the predetermined chemical processing are lifted by the lifter 20 and delivered from the lifter 20 to the rotor 30 until the drying process is completed. 4 is a timing chart showing an example of the number of rotations of a motor 31 that is a component of the rotor 30.
[0035]
In a period before time t0, the substrate W held by the lifter 20 is immersed in a processing liquid stored in the processing tank 10 and subjected to a predetermined substrate processing such as a cleaning processing. When the predetermined substrate processing is completed, the plurality of substrates W are raised to the lifting position (the one-dot chain line position in FIG. 1) by the lifter 20, and transferred from the lifter 20 to the rotor 30. The valve 42 communicating with the nitrogen gas supply source 43 is opened during a period until the substrate W is lifted from the dipping position (solid line position in FIG. 1) and held up, and the atmosphere in the container 1 is In addition, since the lifter 20 is quickly raised from the dipping position to the lifting position, the water mark generated by moisture adhering to the surface of the substrate W is suppressed, and the drying process is performed. The substrate W can be raised to the lifted position. Since the atmosphere in the container 1 is connected to the outside of the substrate processing apparatus 100 via the exhaust pipe 17, the pressure in the container 1 is kept constant even if nitrogen gas is continuously supplied.
[0036]
At time t0, the rotation speed n of the stopped motor 31 is n₀And the substrate W held by the rotor 30 starts to rotate. At time t0, the valve 42 is opened and the inside of the container 1 is in a nitrogen atmosphere.
[0037]
Next, the rotational speed of the motor 31 is n₀In this state, at time t1, the valve 62 communicating with the pure water supply source 63 is opened, and pure water is supplied to the plurality of substrates W held by the rotor 30 to clean the substrate W with pure water. At this time, the valve 42 is opened, and the substrate W is cleaned with pure water while rotating in a nitrogen atmosphere. Therefore, the cleaning process can proceed while suppressing the generation of watermarks on the substrate W.
[0038]
As will be described in detail later, at the next time t <b> 2, the hydrofluoroether (hereinafter also referred to as “HFE”) of the fluorinated solvent contained in the dry solvent supply source 56 in a liquid state is supplied from the desiccant discharge nozzle 50. By spraying, the vapor | steam of HFE is supplied to the board | substrate W as a desiccant. Here, HFE is a fluorine-based compound that does not contain a chlorine atom in its structure, and does not cause ozone layer destruction, which has become a problem in recent years, and it is also considered environmental issues that have little impact on global warming. Organic solvent. Further, it is not flammable as compared with IPA used as a drying solvent in the conventional drying treatment. Therefore, it is not necessary to provide a special safety mechanism such as an explosion-proof structure as in a conventional substrate processing apparatus that performs a drying process using IPA, and the substrate processing apparatus can be prevented from being enlarged. Furthermore, since it is not necessary to perform a predetermined drainage process to be a harmless substance, the cost for the drainage process can be reduced.
[0039]
HFE has a small surface tension, that of water is 71.8 dyn / cm and IPA is 20.8 dyn / cm, whereas the surface tension of HFE is 16.6 dyn / cm or less. Therefore, the permeability of HFE is higher than that of IPA, and water droplets that have entered the fine wiring pattern formed on the substrate W such as a trench structure can be easily dried, and the drainage efficiency of water droplets that have entered the wiring pattern Can be improved.
[0040]
Further, HFE has a small latent heat of vaporization, that of water is 2256 J / g and IPA is 674 J / g, whereas the low molecular weight silicone solvent has a latent heat of evaporation of 210 J / g or less. Therefore, the drying process using HFE can shorten the time required for drying compared to the case where IPA is used.
[0041]
Due to the physical properties of HFE, the drying process using HFE as a desiccant improves the drainage efficiency of the moisture that has entered the fine pattern compared with the conventional drying process using IPA, while reducing the drying time. It can be shortened. Therefore, it is possible to further suppress the generation of a watermark due to moisture that has entered the fine pattern.
[0042]
The operation at the time t2 will be described in detail. The valve 62 is closed to stop supplying pure water, the valve 42 is closed to stop supplying nitrogen gas, and the valve 52 connected to the dry solvent supply source 56 is opened, so that the substrate W is used as a desiccant. HFE is supplied to the substrate W. At time t2, the rotation speed n of the motor 31 is set to n.₀To n₁To lower.
[0043]
Here, the rotational speed n of the motor 31 is decreased by supplying the HFE to the entire surface of the substrate W while being supplied to the substrate W and staying on the substrate without being shaken off by the centrifugal force caused by the rotation of the motor 31. This is to increase the replacement efficiency between the pure water adhering to the substrate W and HFE. At this time, the HFE supplied to the substrate W is replaced with pure water adhering to the surface or pure water that has entered the fine pattern.
[0044]
Subsequently, at time t3, the valve 52 is closed and the supply of HFE is stopped, and the valve 42 is opened and nitrogen gas is resupplied into the container 1, and the inside of the container 1 is replaced with a nitrogen gas atmosphere. In addition, the rotational speed of the motor 31 is n₁To n₀Will be increased. Therefore, the pure water adhering to the substrate W and most of the HFE are removed by being shaken off by the centrifugal force due to the rotation. Further, the HFE that has entered the fine pattern such as the trench structure is evaporated and removed from the substrate W. At this time, nitrogen gas continues to be supplied into the container 1 that is connected to the outside via the exhaust pipe 17, and the vaporized HFE vapor is quickly replaced with nitrogen gas. Since the density of the HFE vapor does not exceed the maximum density at which the HFE vapor determined by the atmospheric temperature in the container 1 can exist, the HFE remaining on the substrate W evaporates quickly. At time t4, the rotation number of the motor 31 is set to zero, the rotation of the substrate W is stopped, and the drying process is finished.
[0045]
(3) Advantages of the substrate processing apparatus of the first embodiment
As described above, in the drying process of the substrate processing apparatus 100 according to the first embodiment, HFE having a small latent heat of evaporation and a small surface tension is used as a desiccant as compared with IPA used in the conventional drying process. The substrate 31 is rotated by the motor 31 while being supplied to the substrate W to which pure water is adhered, and the water droplets on the substrate W and the fluorinated solvent are separated by centrifugal force while improving the drainage efficiency of the water droplets inside the fine pattern. It can be removed at once by shaking. Therefore, it is possible to improve the drying performance while further suppressing the drying failure inside the fine pattern.
[0046]
In addition, by using HFE as a desiccant, it is not necessary to install a special explosion-proof device that is essential in the conventional substrate processing apparatus using IPA, thereby suppressing an increase in cost required for the drying process. be able to. In addition, HFE does not contain chlorine atoms in its structure, does not cause ozone layer destruction that has become a problem in recent years, and has little impact on global warming, so it is harmless by performing drainage treatment. There is no need to use a substance, and the cost for the drainage treatment can be reduced.
[0047]
In addition, when HFE is supplied to the substrate W, by reducing the rotation speed of the motor 31, the replacement efficiency between the pure water adhering to the substrate W and HFE can be increased, so that the drying efficiency can be increased. it can.
[0048]
Moreover, since the substrate processing apparatus 100 of 1st Embodiment can hold | maintain the several board | substrate W and can perform a drying process simultaneously, it can improve the throughput of a process.
[0049]
<2. Second Embodiment>
Next, a second embodiment of the present invention will be described. The substrate processing apparatus according to the second embodiment is different from the first embodiment except that the desiccant supply mechanism is different and the desiccant supplied to the substrate W is different as described later. This is the same as the embodiment. Therefore, in the following, this difference will be mainly described.
[0050]
(1) Configuration of substrate processing equipment
In FIG. 5, the front view of the substrate processing apparatus 100 in 2nd Embodiment of this invention is shown.
In the drying process in the second embodiment, the drying process is performed by supplying HFE vapor to the plurality of substrates W instead of the HFE solvent as a drying agent. Therefore, here, the mechanical configuration of the substrate processing apparatus 100 will be described focusing on the HFE vapor supply unit.
[0051]
As shown in FIG. 5, the two desiccant discharge nozzles 50 are connected in communication with a dry gas supply source 53 via pipes 51 (51 a, 51 b, 51 c, 51 d) and a valve 52. The dry gas supply source 53 stores HFE, which is a fluorinated solvent, in a liquid state. The dry gas supply source 53 is connected to a nitrogen gas supply source 55 through a pipe 54, and supplies nitrogen gas as bubbles to the HFE stored in the dry gas supply source 53, so-called nitrogen. Gas bubbling can be performed. Therefore, the gas phase (gas) of HFE is mixed in the nitrogen gas by this bubbling, and the dry gas composed of HFE vapor is sent to the pipe 51 using the nitrogen gas as a carrier gas to the rotor 30 from the two desiccant discharge nozzles 50. Supply to a plurality of held substrates W.
[0052]
(2) Substrate drying process sequence
Here, a substrate drying process sequence performed by the substrate processing apparatus 100 according to the second embodiment will be described. As in the first embodiment, FIG. 6 shows the open / closed state of the valves 40, 50, 60 from the time t0 when the plurality of substrates W on which the predetermined chemical liquid processing has been completed is held in the rotor 30 until the drying processing is completed. 3 is a timing chart showing an example of the number of rotations of a motor 31 that is a component of the rotor 30. Here, the points different from the first embodiment will be mainly described.
[0053]
At time t0, the rotation speed n of the stopped motor 31 is n₀And the substrate W held by the rotor 30 starts to rotate.
[0054]
Next, the rotational speed of the motor 31 is n₀In this state, at time t1, the valve 62 communicating with the pure water supply source 63 is opened, and pure water is supplied to the plurality of substrates W held by the rotor 30 to clean the substrate W with pure water. At this time, the inside of the container 1 is in a nitrogen atmosphere, and since the substrate W is supplied with pure water while being rotated by the motor 31, generation of watermarks can be suppressed.
[0055]
Subsequently, at time t2, the valve 62 is closed to supply pure water, the valve 42 is closed to stop supplying nitrogen gas, and the valve 52 connected to the dry solvent supply source 56 is opened. Then, HFE vapor is supplied to the substrate W as a desiccant. At this time, the HFE vapor is condensed on the substrate W and replaced with water droplets. HFE has a smaller surface tension and lower latent heat of vaporization than IPA used as a desiccant in the conventional drying process, so water droplets that enter inside fine wiring patterns such as trench structures can be drained well. Can be dried. Furthermore, when using HFE vapor | steam as a desiccant, the usage-amount of HFE can be reduced compared with the case where an HFE solvent is used.
[0056]
At time t2, the rotation speed n of the motor 31 is n.₁And the rotation speed of the substrate is lowered. At this time, the number of rotations of the motor 31 is n₁The reason for this is that HFE is efficiently condensed on the substrate W.
[0057]
Subsequently, at time t3, the supply of HFE is stopped and nitrogen gas is resupplied into the container 1, and the HFE vapor in the container 1 is replaced with nitrogen gas and exhausted through the exhaust pipe 17. It is exhausted to the drain 18. Further, the rotational speed of the motor 31 is n₁To n₀Will be increased. As a result, pure water adhering to the substrate W and most of the HFE are shaken off by the centrifugal force due to rotation, and the HFE that has entered the fine pattern such as the trench structure is vaporized and removed from the substrate W. At time t4, the rotation number of the motor 31 is set to zero, the rotation of the substrate W is stopped, and the drying process is finished.
[0058]
(3) Advantages of the substrate processing apparatus of the second embodiment
As described above, in the second embodiment, the HFE vapor is supplied to the substrate W, and the HFE vapor condensed on the substrate W and the pure water are replaced to perform the drying process of the substrate processing apparatus 100. The drying process of the second embodiment can have the same advantages as the first embodiment.
[0059]
Furthermore, in 2nd Embodiment, when using HFE vapor | steam as a desiccant, compared with the case where an HFE solvent is used, the amount of HFE used in a drying process can be reduced and process liquid cost can be reduced.
[0060]
<3. Third Embodiment>
(1) Configuration of substrate processing equipment
Here, a third embodiment of the present invention will be described. FIG. 7 shows a front view of the substrate processing apparatus 200 in the third embodiment, and FIG. 8 shows a top view of the substrate processing apparatus 200 shown in FIG. The substrate processing apparatus 200 according to the third embodiment is a so-called single-wafer type substrate processing apparatus, and can perform substrate processing for each substrate, so that variations in processing between substrates can be suppressed.
[0061]
As shown in FIG. 7, the substrate processing apparatus 200 in the third embodiment rotates while holding the substrate W in a substantially horizontal posture, and supplies a processing liquid from above the substrate W to perform a predetermined substrate processing. And mainly includes a spin base 110, an atmosphere shielding plate 120, and a cup 130.
[0062]
The spin base 110 has a plurality of chuck pins 111 erected on the upper surface thereof. Each of the plurality of chuck pins 111 holds the peripheral edge of the substrate W, thereby holding the substrate W in a substantially horizontal posture at a predetermined interval from the spin base 110. At this time, the upper end portion of the chuck pin 111 slightly protrudes from the upper surface of the substrate W in order to securely grip the peripheral portion of the substrate W.
[0063]
A rotation shaft 112 is suspended from the lower surface side of the center portion of the spin base 110. The rotating shaft 112 is linked to the motor 113 via a belt driving mechanism 114. When the motor 113 is driven, the driving force is transmitted to the rotating shaft 112 via the belt driving mechanism 114, and the substrate W held on the chuck pin 111 together with the rotating shaft 112 and the spin base 110 is along the vertical direction in the horizontal plane. It is rotated in the direction of arrow AR5 around the axis.
[0064]
The atmosphere blocking plate 120 is a disk-shaped member provided to face the spin base 110. A rotation shaft 122 is suspended from the upper surface side of the central portion of the atmosphere blocking plate 120. The inside of the rotating shaft 122 is hollow, and the treatment liquid nozzle 121 is inserted into the hollow portion. The rotating shaft 122 is connected to the motor 123. When the motor 123 is driven, the atmosphere blocking plate 120 is rotated about the axis along the vertical direction in the horizontal plane via the rotation shaft 122. That is, the atmosphere blocking plate 120 is rotated in parallel and coaxially with the substrate W and at substantially the same rotational speed.
[0065]
Further, the processing liquid nozzle 121 is connected to a dry solvent supply source 156 through a pipe 151 (151a, 151b) and a valve 152. Therefore, the dry solvent is discharged from the processing liquid nozzle 121 onto the upper surface of the substrate W by opening the valve 152. The pipe 151 is also connected to a chemical solution supply source (not shown), and a chemical solution treatment can be performed on a substrate W by opening and closing a valve (not shown).
[0066]
On the other hand, a gap between the inner wall of the rotating shaft 122 and the treatment liquid nozzle 121 is connected to a nitrogen gas supply source 143 through a pipe 141 (141a, 141b) and a valve 142. Therefore, by opening the valve 142, nitrogen gas is supplied as an inert gas from the rotating shaft 122 to the upper surface of the substrate W.
[0067]
The cup 130 is disposed so as to surround the periphery of the spin base 110, the substrate W held by the spin base 110, and the atmosphere blocking plate 120, and collects the processing liquid scattered by the rotation thereof. The collected processing liquid is discharged to a drainage drain 116 outside the substrate processing apparatus 200 via a discharge port 131 and a drainage pipe 115 (115a, 115b, 115c) provided at the bottom of the cup 130.
[0068]
In addition, this type of substrate processing apparatus is normally installed in a clean room, and a downflow of clean air flowing down the clean room flows from the upper opening of the cup 130. The clean air that has flowed into the cup 130 is exhausted to the exhaust drain 118 outside the substrate processing apparatus 200 via a discharge port 131 and exhaust pipes 117 (117 a, 117 b, 117 c) provided at the bottom of the cup 130. At this time, a minute mist of the processing liquid floating in the cup 130 is also exhausted.
[0069]
In addition to the above, this substrate processing apparatus is provided with, for example, a mechanism for raising and lowering the cup 130 and the atmosphere blocking plate 120 in the direction of the arrow AR3.
[0070]
As shown in FIG. 8, a pure water discharge nozzle 160 is provided at a predetermined position on the side of the cup 130 so as to be rotatable in the direction of an arrow AR6. The pure water discharge nozzle 160 is connected in communication with a pure water supply source 163 via a pipe 161 (161a, 161b) and a valve 162. Therefore, the atmosphere blocking plate 120 is moved to a predetermined position where it does not interfere with the pure water discharge nozzle 160, the discharge port of the pure water discharge nozzle 160 is moved to a position immediately above the center position on the substrate W, and the valve 162 is opened. Then, pure water is supplied to the substrate W.
[0071]
The control unit 170 includes a memory 171 that stores programs, variables, and the like, and a CPU 172 that executes control in accordance with the programs stored in the memory 171. The CPU 172 performs the rotation control of the motors 113 and 123, the raising / lowering control of the atmosphere shielding plate 120 and the cup 130, the opening / closing control of each valve, and the like at predetermined timings according to the program stored in the memory 171.
[0072]
(2) Substrate drying process sequence
Here, a substrate drying process sequence by the substrate processing apparatus 200 according to the third embodiment will be described. FIG. 9 is a timing chart showing an example of the open / close states of the valves 142, 152, 162 and the rotation speeds of the motors 113, 123 from the time t0 when the predetermined chemical solution process is completed until the drying process is completed.
[0073]
In a period before time t0, an unprocessed substrate W is transferred to the spin base 110 by a transfer robot (not shown), and the peripheral portion is held by the chuck pins 111, whereby the substrate W is held in a horizontal posture. The Next, the atmosphere shielding plate 120 is close to the spin base 110 and covers the upper portion of the substrate W, and the cup 130 is positioned so as to surround the periphery of the spin base 110 and the atmosphere shielding plate 120. Subsequently, the spin base 110 and the atmosphere blocking plate 120 are rotated, and accordingly, the substrate W held on the spin base 110 is rotated. Then, a predetermined chemical liquid process is performed on the rotating substrate W by discharging a predetermined chemical liquid from the processing liquid nozzle 121.
[0074]
At time t0, the atmosphere blocking plate 120 is raised in the arrow AR3 direction to a position where it does not interfere with the pure water discharge nozzle 160, and the pure water discharge nozzle 160 is moved from the retracted position (solid line position in FIG. 8) to the discharge position (in FIG. 8). The position of the discharge port of the pure water discharge nozzle 160 is moved to a predetermined position above the substrate W. When the movement of the pure water discharge nozzle 160 is completed, the valve 162 communicating with the pure water supply source 163 is opened, and pure water is discharged from the pure water discharge nozzle 160 and supplied to the substrate W. At this time, the motor 113 has a rotational speed n.₀Therefore, the pure water discharged onto the substrate W spreads from the pure water dropping position toward the outside of the substrate due to the centrifugal force caused by the rotation, and the cleaning process proceeds.
[0075]
Further, at time t0, the valve 142 is opened, and nitrogen gas is continuously supplied from the gap between the inner wall of the rotating shaft 122 connected to the nitrogen gas supply source 143 and the processing liquid nozzle 121. Therefore, the vicinity of the substrate W becomes a nitrogen gas atmosphere, and the contact between the substrate W and oxygen can be suppressed, and the generation of watermarks can be suppressed.
[0076]
Next, at time t1, the valve 162 is closed and the supply of pure water is stopped, the pure water discharge nozzle 160 is moved from the discharge position to the retracted position, and the valve 142 is closed and the supply of nitrogen gas is stopped. Is done. Further, at time t1, the atmosphere blocking plate 120 is lowered in the direction of the arrow AR3 from a position where it does not interfere with the pure water discharge nozzle 160 and is moved to a position where it does not interfere with the plurality of chuck pins 111. Further, the valve 152 communicating with the dry solvent supply source 156 is opened so that HFE is supplied to the substrate W as a desiccant to the substrate W, and the rotational speed n ′ of the motor 113 is set to n₀'To n₁'Decrease to.
[0077]
Here, the purpose of lowering the atmosphere blocking plate 120 is to prevent the processing liquid and contaminants bounced from the cup 130 when rotating the substrate W from adhering to the surface of the substrate W. The reason why the rotational speed n ′ of the motor 113 is reduced is that the HFE is supplied to the substrate W and spreads over the entire surface of the substrate W while the HFE is not shaken off by the centrifugal force generated by the rotation of the motor 31 and remains on the substrate. It is. The HFE supplied to the substrate W also enters the fine pattern.
[0078]
As described above, in the third embodiment, HFE is used as a desiccant as in the first embodiment. HFE has lower surface tension and lower latent heat of vaporization than IPA used in the conventional drying process. Time can be shortened, and the generation of watermarks due to moisture entering the fine pattern can be further suppressed.
[0079]
Subsequently, at time t2, the valve 152 is closed and the supply of HFE is stopped, the valve 142 is opened and nitrogen gas is supplied again, and the vicinity of the substrate W is replaced with a nitrogen gas atmosphere. 113 is n₁'To n₀'Increased to. Therefore, the pure water adhering to the substrate W and most of the HFE are shaken off by the centrifugal force due to the rotation and removed, and the water droplets on the substrate W can be efficiently removed.
[0080]
Further, the HFE that has entered the fine pattern is vaporized and removed from the substrate W. At this time, the atmosphere in the vicinity of the substrate W is connected to the exhaust drain 118 through the exhaust port 131 and the exhaust pipe 117, and the vaporized HFE vapor is quickly replaced with nitrogen gas. The remaining HFE evaporates quickly. At time t3, the rotational speed n ′ of the motor 113 is set to zero, the rotation of the substrate W is stopped, and the drying process ends.
[0081]
(3) Advantages of the substrate processing apparatus of the third embodiment
As described above, in the drying process of the substrate processing apparatus 200 according to the third embodiment, as in the first embodiment, the motor is supplied with HFE vapor, which is a fluorinated solvent, as a desiccant to the substrate W to which pure water has adhered. By rotating the substrate W by 113, the replacement efficiency of the water droplets inside the fine pattern formed on the substrate W and the desiccant is improved, and the drainage efficiency of the water droplets inside the fine pattern is improved, while the substrate W is improved. The upper water droplets and the fluorinated solvent can be removed at once by shaking off with centrifugal force. Therefore, compared with the conventional drying process which uses IPA as a desiccant, drying performance can be improved, further suppressing the drying defect inside a fine pattern.
[0082]
In addition, since HFE is used as a desiccant, it is not necessary to install a special apparatus for explosion prevention like the conventional substrate processing apparatus as in the first embodiment, and the cost required for the drying process is increased. Can be suppressed. Furthermore, HFE does not cause destruction of the ozone layer and has little influence on global warming, so that the cost for drainage treatment can be reduced.
[0083]
Further, when HFE is supplied to the substrate W, the drying efficiency can be increased by reducing the rotation speed of the motor 113.
[0084]
Further, by performing substrate processing one by one, it is possible to suppress drying defects while suppressing variations in drying processing between substrates.
[0085]
<4. Modification>
The first to third embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made.
[0086]
In the first embodiment and the third embodiment, the fluorine-based solvent HFE is used as the desiccant, but IPA is 1% to 10% (preferably 3% to 7%, particularly preferably 5%) to the HFE. A solvent mixed by about volume (hereinafter, also referred to as “HFE mixed solvent”) may be used. By using the HFE mixed solvent as a desiccant, the permeability between pure water and the dry solvent can be further increased. Therefore, the drainage efficiency of water droplets entering the fine pattern formed on the substrate is increased, and the drying efficiency is increased. Can be improved. That is, as the desiccant in the present invention, not only pure HFE but also a desiccant mainly composed of HFE can be used.
[0087]
In the second embodiment, HFE, which is a fluorinated solvent, is stored in the dry gas supply source 53. Instead, the HFE mixed solvent is stored, and the vapor of the HFE mixed solvent is supplied to the substrate. Also good. Since the HFE mixed solvent condensed on the substrate has higher permeability to pure water than HFE, the drainage efficiency of water droplets entering the fine pattern formed on the substrate is improved and the drying efficiency is improved. Can do.
[0088]
In the second embodiment, the dry gas supply source 53 stores HFE, which is a fluorinated solvent. However, instead of this, a desiccant containing a silicone solvent as a main agent may be stored. For example, in the case of a low molecular silicone solvent from a dimer to a pentamer, the latent heat of vaporization is 2256 J / g for pure water and 674 J / g for IPA, whereas the latent heat for evaporation of a low molecular silicone solvent is The surface tension of water is 71.8 dyn / cm and IPA is 20.8 dyn / cm, whereas the surface tension of the low molecular weight silicone solvent is 16.5 dyn / cm or less. Therefore, when the vapor of silicone solvent using nitrogen gas as the carrier gas is used as the dry gas, it has excellent permeability to pure water and also increases the drying speed compared to the case of using IPA vapor. The drying performance can be improved as in the case of the vapor of the fluorinated solvent.
[0089]
【The invention's effect】
  From claim 1Claim 6According to the invention described in the above, the substrate is rotated while supplying a desiccant mainly composed of a fluorinated solvent onto the substrate on which pure water is adhered, so that the inside of a fine pattern such as a trench structure formed on the substrate can be obtained. While draining the water droplets, the pure water and the fluorinated solvent on the substrate can be removed at once by shaking off with centrifugal force. Therefore, it is possible to improve the drying performance while suppressing poor drying inside the fine pattern.
[0090]
  Also,Claims 1 to 6According to the invention described in (4), since a plurality of substrates can be dried at the same time, the throughput of the drying process can be improved.
[0092]
  In particular,Claim 2According to the invention described in the above, by supplying a desiccant mainly containing a fluorinated solvent, the substrate rotational speed is decreased, thereby further improving the drainage efficiency of pure water inside the fine pattern and improving the drying efficiency. Can do.
[0093]
  In particular,Claim 3According to the invention described in the above, the desiccant mainly containing the fluorinated solvent in the pure water adhering portion by supplying the fluorinated solvent vapor to the substrate and efficiently bringing the substrate and the fluorinated solvent vapor into contact with each other. Therefore, the drying performance can be improved while reducing the amount of the fluorinated solvent used.
[0094]
  In particular,Claim 4According to the invention described in the above, pure water adhering to the substrate is replaced with hydrofluoroether by using hydrofluoroether having a small surface tension and low latent heat of vaporization as the main agent of the desiccant compared with pure water. Therefore, drying efficiency can be improved.
[0095]
Moreover, since hydrofluoroether is nonflammable and it is not necessary to install a special device for explosion prevention, an increase in cost required for the drying process can be suppressed.
[0096]
In addition, hydrofluoroethers do not contain chlorine atoms in their structure, do not cause ozone layer destruction that has become a problem in recent years, and have little impact on global warming. Since it is a solvent and does not need to be drained to be a harmless substance, the cost for draining can be reduced.
[0097]
  In particular,Claim 5According to the invention described in the above, by using a solvent in which isopropyl alcohol is mixed with a fluorinated solvent as a desiccant, as compared with the case where only the fluorinated solvent is used as a desiccant, a desiccant and pure water are used. Therefore, the drying efficiency can be increased.
[0098]
  Claim 7According to the invention described in the above, while the substrate is rotated while supplying a desiccant mainly composed of a silicone solvent on the substrate to which pure water is adhered, the pure water on the substrate is removed by shaking off by centrifugal force. Since the substrate can be dried while draining water droplets inside the fine pattern such as the trench structure, the same effect as in the first aspect is obtained.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a substrate processing apparatus according to a first embodiment of the present invention.
FIG. 2 is a side view of the substrate processing apparatus of FIG.
FIG. 3 is a perspective view of the rotor of FIG. 1;
FIG. 4 is a timing chart showing an example of a valve opening / closing state of a supply unit and the number of rotations of a motor in the first embodiment of the present invention.
FIG. 5 is a diagram illustrating an overall configuration of a substrate processing apparatus according to a second embodiment of the present invention.
FIG. 6 is a timing chart showing an example of a valve opening / closing state of a supply unit and the number of rotations of a motor in a second embodiment of the present invention.
FIG. 7 is a diagram showing an overall configuration of a substrate processing apparatus according to a third embodiment of the present invention.
8 is a top view of the substrate processing apparatus of FIG. 7. FIG.
FIG. 9 is a timing chart showing an example of a valve opening / closing state of a supply unit and the number of rotations of a motor in a third embodiment of the present invention.
[Explanation of symbols]
100 Substrate processing equipment
1 container
30 rotor
50 Desiccant discharge nozzle
56 Dry solvent source
200 Substrate processing equipment
110 spin base
113 motor
121 Treatment liquid nozzle
156 Dry solvent source
W substrate

Claims (7)

A substrate processing apparatus that performs a drying process on a plurality of substrates that have been cleaned with a processing solution,
A treatment tank for storing a treatment liquid and immersing a plurality of substrates in the treatment liquid to perform a predetermined substrate treatment ;
And withdrawal means withdraw from the treatment vessel while maintaining at a substantially vertical posture the plurality of substrates wherein the substrate processing is completed,
A holding unit that is provided above the processing tank and holds the plurality of substrates delivered from the lifting unit in a substantially vertical posture ;
A rotating means for holding a plurality of substrates around a rotation axis along a substantially horizontal direction and rotating the holding means ;
A solvent supply means for supplying a desiccant mainly composed of a fluorinated solvent to the substrate to which the processing liquid is adhered while rotating the substrate using the rotating means;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
A rotation speed control means for reducing the rotation speed of the substrate by the rotation means when supplying the desiccant from the solvent supply means to the substrate held by the holding means ;
The substrate processing apparatus characterized by obtaining further Bei a. The substrate processing apparatus according to claim 1 or 2 , wherein
The solvent supply means, a substrate processing apparatus which is characterized that you provide steam of desiccant substrate. A substrate processing apparatus according to any one of claims 1 to 3,
The fluorinated solvent is a substrate processing apparatus according to claim hydrofluoroether der Rukoto. The substrate processing apparatus according to claim 1, wherein:
The drying agent is a substrate processing apparatus according to claim solvent der Rukoto of a mixture of said fluorine-based solvent and isopropyl alcohol. A substrate processing method for drying a substrate that has been cleaned with a processing solution ,
(a) a step of immersing a plurality of substrates in a processing solution stored in a processing tank and performing a predetermined substrate processing;
(b) a step of lifting the plurality of substrates from which the step (a) has been completed from the processing tank while being held in a substantially vertical posture by the lifting means ;
(c) transferring a plurality of substrates in a substantially vertical posture lifted in the step (b) from the lifting means to the holding means ;
(d) supplying a desiccant containing a fluorinated solvent as a main agent to the substrate on which the processing liquid is adhered while rotating the substrate held by the holding means ;
A substrate processing method comprising: A substrate processing apparatus that performs a drying process on a substrate that has been cleaned with a processing liquid ,
A treatment tank for storing a treatment liquid and immersing a plurality of substrates in the treatment liquid to perform a predetermined substrate treatment ;
And withdrawal means withdraw from the treatment vessel while maintaining at a substantially vertical posture the plurality of substrates wherein the substrate processing is completed,
A holding unit that is provided above the processing tank and holds the plurality of substrates delivered from the lifting unit in a substantially vertical posture ;
A rotating means for holding a plurality of substrates around a rotation axis along a substantially horizontal direction and rotating the holding means ;
A solvent supply means for supplying a desiccant mainly composed of a silicone-based solvent to the substrate on which the treatment liquid is adhered, while rotating the substrate using the rotation means ;
The substrate processing apparatus according to claim Rukoto equipped with.

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