JP3865969B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, 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 simply referred to as “substrate”) are immersed in the processing liquid, and the substrate is detached from the processing liquid. It is related with the substrate processing apparatus which performs a predetermined process by doing.
[0002]
[Prior art]
Conventionally, in the manufacturing process of the substrate, after sequentially performing a treatment with a chemical solution such as hydrofluoric acid and a cleaning treatment with pure water, isopropyl alcohol (hereinafter referred to as “IPA”) or the like while pulling out the substrate from the pure water. 2. Description of the Related Art Substrate processing apparatuses that perform drying by supplying an organic solvent vapor to the periphery of a substrate are used.
[0003]
In general, there are two known methods for performing a drying process while pulling out a substrate from pure water: pull-up drying and pull-down drying.
[0004]
Pull-up drying is a technique for performing a drying process while pulling up a substrate placed on a lifter or the like from a processing solution. That is, the substrate is placed on the lifter, and is lowered and immersed in the processing liquid in the processing tank by the lifter. Then, after the dipping process (usually a cleaning process with pure water) is finished, the substrate is dried by lifting the substrate from the processing tank with a lifter, supplying IPA to the periphery of the substrate, and then setting the atmosphere under reduced pressure. Is going.
[0005]
On the other hand, pull-down drying is a technique for drying a substrate by draining the processing liquid in the processing tank. That is, the substrate is held in a fixed position in the processing tank, and the immersion process proceeds by filling the processing tank with the processing liquid. When the immersion process is completed, the processing liquid in the processing tank is drained while the substrate is held at a fixed position, and the liquid level is lowered to expose the substrate to the air. Then, IPA is supplied to the periphery of the substrate, and after that, the substrate is dried by setting a reduced pressure atmosphere.
[0006]
[Problems to be solved by the invention]
However, when lifting and drying, since the substrate is moved up and down by the lifter, a slight amount of friction is generated between the substrate and the lifter due to the vibration of the drive unit of the lifter during the movement, and contaminants such as particles accompanying the friction are generated. May occur and adhere to the substrate. Although the amount of particles generated by the vibration of the lifter driving unit is very small, the amount of particles during the drying process is reduced due to the advancement of technology, and under the recent situation where a higher degree of cleanliness is required, Even such a small amount of particles is a problem.
[0007]
On the other hand, when performing drying by pulling down, particles are not generated due to vibration of the lifter drive unit because the substrate is not moved, but particles that float on the liquid level as the liquid level in the treatment tank decreases. The problem of adhering to the substrate occurs.
[0008]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a substrate processing apparatus that can reduce the adhesion of particles to a substrate when the substrate is detached from the processing liquid.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention of claim 1 is a substrate processing apparatus for performing a predetermined process by immersing a substrate in a processing solution and detaching the substrate from the processing solution. A processing tank for storing the processing liquid; (b) a liquid supply means provided in the processing tank for supplying the processing liquid to the processing tank; (c) a holding means for holding the substrate; and (d). Raising the processing tank to immerse the substrate held in the holding means in the processing liquid, and supplying the processing liquid from the liquid supply means while overflowing the processing liquid from the processing tank, the processing tank A processing tank lifting / lowering means capable of lowering the substrate and separating the substrate held by the holding means from the processing liquid, (e) an openable / closable opening / closing part provided above the processing tank, and the processing Surrounding the space between the tank and the opening / closing part And a shielding surface for蔽, while closing the opening portion, a closed space defining means for defining a closed space volume is changed according to an elevating state of the processing tank above the processing bath, ( f) decompression means for decompressing the closed space; and (g) gas supply means for supplying a predetermined gas to the closed space when the processing tank is raised .
[0012]
According to a second aspect of the present invention, in the substrate processing apparatus according to the first aspect of the present invention, the substrate processing apparatus further comprises a holding means raising / lowering means for raising and lowering the holding means.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
<1. Configuration of substrate processing apparatus>
First, the configuration of the substrate processing apparatus according to the present invention will be described. FIG. 1 is a front view of the substrate processing apparatus. FIG. 2 is a side view of the substrate processing apparatus.
[0015]
This substrate processing apparatus is an apparatus for performing a drying process by detaching a substrate from pure water after immersing the substrate in pure water for cleaning. The substrate processing apparatus includes an outer tank 10, a processing tank 20, a lifter arm 30, and a tank lifting mechanism 40.
[0016]
The treatment tank 20 is a tank capable of storing a chemical solution such as hydrofluoric acid or pure water (hereinafter collectively referred to as “treatment liquid”) and performing surface treatment on the substrate. Housed inside. A liquid supply nozzle 25 for supplying a processing liquid to the processing tank 20 is provided inside the processing tank 20. The liquid supply nozzle 25 is connected to the processing liquid supply port of the outer tub 10 via a bellows 26 (see FIG. 2). Further, the processing liquid supply port is connected to a processing liquid supply source (not shown). Accordingly, the processing liquid supplied from the processing liquid supply source is guided to the liquid supply nozzle 25 through the bellows 26 and discharged into the processing tank 20.
[0017]
In addition, the treatment tank 20 is provided with a quick drain valve 27 at a lower portion thereof. The quick drain valve 27 is a large-diameter valve, and can quickly drain the processing liquid stored in the processing tank 20 in the open state. The quick drain valve 27 is connected to the drain port of the outer tub 10 via the bellows 28. The processing liquid drained from the quick drain valve 27 flows through the bellows 28 and is discharged to the outside of the outer tub 10.
[0018]
The lifter arm 30 is provided so that a plurality of substrates W can be placed in the outer tub 10. Three holding portions 31, 32, and 33 are fixed to the lifter arm 30. Each of the three holding portions 31, 32, 33 is provided with a plurality of holding grooves arranged at predetermined intervals so that the outer edge portion of the substrate W fits in and holds the substrate W in an upright posture.
[0019]
The lifter arm 30 can be moved up and down in the vertical direction by a lifter 35. The lifter 35 includes a motor 36 and a ball screw 37. A lifter arm 30 is screwed onto the ball screw 37, and the ball screw 37 is rotatable by a motor 36. When the motor 36 rotates the ball screw 37 in the forward or reverse direction, the lifter arm 30 screwed to the ball screw 37 moves up and down.
[0020]
In the state where the lifter arm 30 is lowered to the processing position (the position indicated by the solid line in FIG. 1), the upper portion of the outer tub 10 is closed by the lid 15. When the lid 15 is closed, the gap between the lid 15 and the outer tub 10 is sealed by the O-ring 12. On the other hand, when the lifter arm 30 is raised to the substrate delivery position (position indicated by a two-dot chain line in FIG. 1), the lid 15 is opened by a lid opening / closing mechanism (not shown), and the upper portion of the outer tub 10 is It is open.
[0021]
In the substrate processing apparatus according to the present invention, a tank lifting mechanism 40 for moving the processing tank 20 up and down is provided in the outer tank 10. The tank lifting mechanism 40 includes a motor 41, a pulley 42, a belt 43, a driven pulley 44, and a ball screw 45. A belt 43 is hung on a pulley 42 connected to the motor 41 and a driven pulley 44 connected to a ball screw 45. When the motor 41 rotates in the forward or reverse direction, the pulley 42 rotates with the rotation, and the belt 43 rotates. Then, the belt 43 rotates the driven pulley 44 and the ball screw 45. A bus holder 21 fixed to the outside of the tank wall of the processing tank 20 is screwed to the ball screw 45. Therefore, when the ball screw 45 is rotated by the rotation of the motor 41, the processing tank 20 is moved up and down.
[0022]
In the state where the lifter arm 30 on which the substrate W is placed is lowered, when the processing tank 20 storing the processing liquid rises to the processing position (the two-dot chain line position in FIG. 1), the substrate W is placed in the processing liquid. Can be immersed. Then, when the processing tank 20 is lowered to the standby position (solid line position in FIG. 1) while the lifter arm 30 is stopped, the substrate W held on the lifter arm 30 is detached from the processing liquid.
[0023]
An upper bellows 18 is provided on the upper side of the bath holder 21 of the processing tank 20. Further, a lower bellows 19 is provided below the bus holder 21. The upper bellows 18 is a seal member that is provided between the upper end of the bath holder 21 and the upper wall of the outer tub 10 so as to be extendable. In a state where the lid 15 (opening / closing portion) is closed, a closed space is formed above the processing tank 20 by the lid 15, the O-ring 12, the upper bellows 18 (shielding surface), and the bath holder 21. Here, since the upper bellows 18 can be expanded and contracted, even if the processing tank 20 is moved up and down, the upper bellows 18 expands and contracts following the operation to maintain the airtightness of the closed space, and the closed space. The size (volume) increases or decreases. The lower bellows 19 is an expandable / contractible seal member provided to shield the tank lifting mechanism 40 from the atmosphere of the processing liquid.
[0024]
A drainage bellows 22 is connected to a part of the bus holder 21. The drainage bellows 22 is a member for discharging the processing liquid overflowing from the processing tank 20 to the bath holder 21 to the outside of the apparatus. Since the drainage bellows 22 is extendable, the drainage function is not lost even when the treatment tank 20 is moved up and down. The bellows 26 for supplying the processing liquid and the bellows 28 for rapid drainage can also freely expand and contract as the processing tank 20 moves up and down.
[0025]
An IPA / N ₂ supply nozzle 50 is disposed inside the outer tub 10 and inside the closed space formed by the upper bellows 18. The IPA / N ₂ supply nozzle 50 is gas supply means for supplying IPA, nitrogen, or a mixed gas thereof derived from a gas supply source outside the apparatus to the closed space.
[0026]
In addition, the substrate processing apparatus includes a decompression unit 60. The decompression unit 60 includes a suction pump and a valve accompanying the suction pump, and can decompress the closed space formed by the upper bellows 18.
[0027]
<2. Operation of substrate processing apparatus>
Next, the operation of the substrate processing apparatus having the above configuration will be described with reference to FIGS. FIG. 3 to FIG. 9 are diagrams for explaining processing in the substrate processing apparatus.
[0028]
First, a plurality of unprocessed substrates W are transferred from the substrate transfer robot (not shown) to the lifter arm 30 (FIG. 3). At this time, the lid 15 is opened, the upper part of the outer tub 10 is opened, and the lifter arm 30 is raised to the substrate delivery position through the open part. Further, the processing tank 20 is lowered by the tank lifting mechanism 40. In the present embodiment, pure water is supplied from the liquid supply nozzle 25 and pure water is stored in the treatment tank 20. The pure water overflowing from the treatment tank 20 is collected by the bath holder 21 and discharged from the drainage bellows 22 to the outside of the outer tank 10.
[0029]
Next, as shown by arrow A1 in FIG. 4, the lifter 35 lowers the lifter arm 30 downward in the vertical direction. As the lifter arm 30 is lowered, the substrate W placed thereon is naturally lowered. At this time, the processing tank 20 does not move while waiting downward. In the treatment tank 20, pure water supply from the liquid supply nozzle 25 is continued, and pure water continues to overflow from the treatment tank 20.
[0030]
When the lifter arm 30 is lowered to a predetermined processing position in the outer tub 10, the lid 15 is closed. When the lid 15 is closed, a closed space is formed above the processing tank 20 by the lid 15, the O-ring 12, the upper bellows 18, and the bath holder 21.
[0031]
Next, as shown by arrow A2 in FIG. 5, the tank lifting mechanism 40 raises the processing tank 20 upward in the vertical direction. At this time, the lifter arm 30 stands by at a predetermined processing position. Further, as described above, the drainage bellows 22, the bellows 26 and the bellows 28 expand and contract in conjunction with the rise of the treatment tank 20.
[0032]
As the processing tank 20 rises, the substrate W held by the lifter arm 30 is gradually immersed in the pure water in the processing tank 20. Eventually, when the processing bath 20 rises to the processing position, the entire substrate W is immersed in the pure water in the processing bath 20 as shown in FIG.
[0033]
By continuing to supply pure water from the liquid supply nozzle 25 in the state shown in FIG. 5, the water washing process of the substrate W proceeds. The water used for the cleaning process overflows from the processing tank 20 and is collected by the bath holder 21 and discharged from the extended drainage bellows 22 to the outside of the outer tank 10.
[0034]
After the substrate W is washed with water for a predetermined time, IPA pre-purge is performed (FIG. 6). The IPA pre-purge is a process in which IPA is ejected upward from the IPA / N ₂ supply nozzle 50 and the inside of the closed space SP formed by the upper bellows 18 is changed to an IPA atmosphere.
[0035]
At this time, since the processing tank 20 is rising, the capacity of the closed space SP is small. Accordingly, the IPA supply amount from the IPA / N ₂ supply nozzle 50 in the pre-purge can be reduced, and the supply time can be shortened. Note that the pure water supply from the liquid supply nozzle 25 is continued even when the IPA pre-purge is being performed, and the pure water overflows from the processing tank 20.
[0036]
When the closed space SP is filled with the IPA atmosphere, the tank lifting mechanism 40 lowers the processing tank 20 downward in the vertical direction as indicated by an arrow A3 in FIG. As the processing tank 20 is lowered, the substrate W is gradually detached from the pure water in the processing tank 20 and when the processing tank 20 is lowered to the original standby position, as shown in FIG. Removed from pure water. In the descending stage of the processing tank 20, pure water supply from the liquid supply nozzle 25 is always continued, and pure water overflows from the processing tank 20.
[0037]
Further, at this stage, the IPA ejection from the IPA / N ₂ supply nozzle 50 is continued, and the IPA purge into the closed space SP is performed. IPA vapor condenses on the surface of the substrate W exposed in the IPA atmosphere, and water droplets attached to the substrate W are replaced with IPA.
[0038]
In the descending stage of the processing tank 20, the lifter arm 30 does not move while waiting at the processing position. Therefore, the vibration accompanying the raising and lowering of the lifter arm 30 is not transmitted to the substrate W, and the friction between the substrate W and the holding portions 31, 32, 33 of the lifter arm 30 due to the vibration of the lifter 35 does not occur. Therefore, generation of particles due to friction is prevented, and particle adhesion to the substrate W can be reduced.
[0039]
In the descending stage of the processing tank 20, pure water supply is always continued from the liquid supply nozzle 25, and pure water overflows from the upper part of the processing tank 20. It will be discharged out of the tank with pure water overflowing from the tank. Therefore, it is possible to prevent such particles floating on the liquid surface from adhering to the substrate W.
[0040]
Thus, since the substrate processing apparatus according to the present invention can move the processing tank 20 itself up and down by the tank lifting mechanism 40, the pure water is supplied to the processing tank 20 while the lifter arm 30 holding the substrate W is stopped. As a result, the treatment tank 20 (that is, the liquid level) can be lowered while being overflowed, and as a result, the adhesion of particles to the substrate W can be reduced. In other words, the substrate processing apparatus according to the present invention moves the processing tank 20 up and down to provide the advantages of conventional pulling and drying (the substrate can be lifted while overflowing pure water from the processing tank) and the advantage of pulling and drying (to the substrate). (Not giving vibration).
[0041]
When the processing tank 20 is lowered to the standby position and the water droplets adhering to the surface of the substrate W are replaced with IPA, the supply of pure water from the liquid supply nozzle 25 is stopped and the quick drain valve 27 is opened to perform processing. Pure water in the tank 20 is quickly drained through the rapid drain valve 27 and the bellows 28. At the same time, nitrogen gas is ejected from the IPA / N ₂ supply nozzle 50 (N ₂ purge), and the IPA atmosphere in the closed space SP is replaced with a nitrogen atmosphere.
[0042]
Thereafter, as indicated by an arrow A4 in FIG. 8, the tank lifting mechanism 40 raises the processing tank 20 again upward in the vertical direction. At this stage, the inside of the processing tank 20 is drained and emptied, and the nitrogen gas ejection from the IPA / N ₂ supply nozzle 50 is stopped.
[0043]
After the processing tank 20 has moved up to the processing position, the decompression unit 60 (see FIG. 1) starts suction, and the inside of the closed space SP is set to a decompressed atmosphere. When the periphery of the substrate W held by the lifter arm 30 is in a reduced pressure atmosphere, the IPA adhering to the substrate W evaporates and the drying of the substrate W is promoted.
[0044]
At this time, since the processing tank 20 is rising, the capacity of the closed space SP is small. Therefore, the burden on the decompression unit 60 in the decompression stage can be reduced and the decompression time can be shortened. This, combined with the reduction in the IPA supply time described above, leads to a reduction in the overall substrate processing time.
[0045]
When the drying of the substrate W is completed, nitrogen gas is again ejected from the IPA / N ₂ supply nozzle 50 to perform N ₂ purge. Then, when the atmospheric pressure in the closed space SP returns to atmospheric pressure, the lid 15 is opened (FIG. 9). Thereafter, the lifter 35 raises the lifter arm 30 upward in the vertical direction, the substrate W is transferred from the lifter arm 30 to the substrate transfer robot, and a series of substrate processing ends.
[0046]
<3. Modification>
While the embodiments of the present invention have been described above, the present invention is not limited to the above examples. For example, in the above-described embodiment, the upper bellows 18 that is an expandable / contractible seal member is used to form a closed space above the processing tank 20, but the present invention is not limited to this, and as shown in FIG. good. FIG. 10 is a front view of another example of the substrate processing apparatus according to the present invention.
[0047]
The substrate processing apparatus shown in FIG. 10 is different from the substrate processing apparatus shown in FIG. 1 in that an O-ring 16 and a seal wall 17 are used instead of the upper bellows 18 that is an elastic seal member. The O-ring 16 is provided at the end of the bus holder 21. The O-ring 16 can seal a gap between the bus holder 21 and the seal wall 17 (so-called O-ring seal) and is slidable with respect to the seal wall 17. Therefore, as in the above embodiment, when the lid 15 is closed, the lid (opening / closing portion) 15, the O-ring 12, the O-ring 16, the seal wall (shielding surface) 17, and the bath holder 21 are placed above the treatment tank 20. A closed space is formed. Since the O-ring 16 is slidable with respect to the seal wall 17, the treatment tank 20 can be raised and lowered, and the airtightness of the closed space is maintained by the raising and lowering, The size (volume) of the closed space increases or decreases. The remaining points are the same as those of the substrate processing apparatus of the above embodiment.
[0048]
Therefore, also in the substrate processing apparatus of FIG. 10, the processing tank 20 itself can be moved up and down by the tank lifting mechanism 40, so that the processing tank is allowed to overflow while pure water is overflowed while the lifter arm 30 holding the substrate W is stopped. 20 can be lowered, and particle adhesion to the substrate W can be reduced. Moreover, since the capacity of the closed space formed above the treatment tank 20 can be reduced in the IPA supply stage and the pressure reduction stage, the IPA supply time and the pressure reduction time can be shortened.
[0049]
Moreover, in the said embodiment, although the lifter arm 30 holding the board | substrate W was stopped, the process tank 20 was raised / lowered and the drying process was performed, However, The lifter arm 30 and the process tank 20 are raised / lowered simultaneously. You may make it perform a drying process. That is, after the cleaning process with pure water is completed, the processing tank 20 is lowered while the lifter arm 30 is raised, and the substrate W is detached from the pure water in the processing tank 20.
[0050]
In this way, it is inevitable that the vibration accompanying the raising and lowering of the lifter arm 30 is transmitted to the substrate W. However, since the lifter arm 30 and the processing tank 20 are simultaneously raised and lowered, the substrate W is quickly detached from the pure water. Can be made. Therefore, in a situation where the shortening of the drying process time is required rather than the cleanliness of the substrate W, this is an optimum mode.
[0051]
Moreover, in the said embodiment, although the lifter 35 and the tank raising / lowering mechanism 40 were comprised using the motor and the ball screw, it is not limited to this, For example, it is good also as a mechanism using a pulley and a belt. Any mechanism that can control the height position and the lifting speed of the lifter 35 and the tank lifting mechanism 40 may be used.
[0052]
Furthermore, the technology according to the present invention can be applied to a so-called one-bath type processing apparatus that performs a chemical treatment and a water washing treatment in one treatment tank, and the chemical treatment and the water washing treatment are performed in different treatment tanks. Even a so-called multi-tank processing apparatus is applicable. When applied to a multi-tank processing apparatus, it is usually effective to apply to the final finishing water washing tank, but it may be applied to other water washing tanks or chemical tanks.
[0053]
【The invention's effect】
As described above, according to the first aspect of the present invention, the processing tank is raised by immersing the substrate held by the holding means in the processing liquid and by supplying the processing liquid from the liquid supply means. The substrate held by the holding means can be released from the processing liquid by lowering the processing tank while overflowing the processing liquid from the processing liquid, so that particles floating on the liquid surface can be removed while the holding means holding the substrate is stopped. The treatment tank can be lowered while overflowing from the treatment tank together with the treatment liquid, and particle adhesion to the substrate can be reduced when the substrate is detached from the treatment liquid. In addition, since the processing tank lifting / lowering means moves up and down the processing tank, the processing tank lifting / lowering means includes a closed space defining means for defining a closed space whose volume changes above the processing tank, and a decompression means for decompressing the closed space. When the decompression means decompresses the closed space, the volume of the decompression means can be reduced, the burden on the decompression means can be reduced, and the decompression time can be shortened. Furthermore, a gas supply means for supplying a predetermined gas to the closed space when the processing tank is rising is provided, so that the gas supply amount can be reduced and the supply time can be shortened.
[0056]
According to the second aspect of the present invention, since the holding means raising / lowering means for raising and lowering the holding means is provided, the holding means and the treatment tank can be raised and lowered at the same time, and the time required for processing can be shortened. .
[Brief description of the drawings]
FIG. 1 is a front view of a substrate processing apparatus according to the present invention.
FIG. 2 is a side view of the substrate processing apparatus of FIG.
FIG. 3 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1;
4 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
5 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
6 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
7 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
8 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
9 is a diagram for explaining a state of processing in the substrate processing apparatus of FIG. 1; FIG.
FIG. 10 is a front view of another example of the substrate processing apparatus according to the present invention.
[Explanation of symbols]
10 the outer tank 15 cover 16 O-ring 17 sealing wall 18 upper bellows 20 treatment vessel 25 liquid supply nozzle 30 lifter arm 35 lifter 40 tank elevating mechanism 50 IPA · N ₂ supply nozzle 60 under reduced pressure section SP closed space W substrate

Claims (2)

A substrate processing apparatus for performing a predetermined process by immersing a substrate in a processing liquid and detaching the substrate from the processing liquid,
(a) a treatment tank for storing the treatment liquid;
(b) a liquid supply means that is provided in the processing tank and supplies the processing liquid to the processing tank;
(c) holding means for holding the substrate;
(d) Raising the treatment tank and immersing the substrate held in the holding means in the treatment liquid, and overflowing the treatment liquid from the treatment tank by supplying the treatment liquid from the liquid supply means A processing tank lifting means capable of lowering the processing tank and releasing the substrate held by the holding means from the processing liquid;
(e) having an openable / closable opening / closing part provided above the processing tank, and a shielding surface that surrounds and shields a space portion between the processing tank and the opening / closing part, and closes the opening / closing part. A closed space defining means for defining a closed space whose volume changes according to the ascending / descending state of the treatment tank above the treatment tank;
(f) decompression means for decompressing the closed space;
(g) gas supply means for supplying a predetermined gas to the closed space when the processing tank is raised;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
A substrate processing apparatus further comprising holding means raising / lowering means for raising and lowering the holding means .

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