JP3625017B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, a processing tank configured to be able to selectively switch and supply chemical and pure water from the bottom of the tank is housed in a sealed chamber, and in this processing tank, a substrate is subjected to chemical processing such as etching and chemical cleaning, The present invention relates to a substrate processing apparatus that performs a pure water cleaning process and performs a drying process for drying a substrate in a sealed chamber after the pure water cleaning process in a processing tank.
[0002]
[Prior art]
As shown in FIG. 13, a conventional substrate processing apparatus of this type is configured such that a processing tank 100 that performs chemical processing and pure water cleaning processing on a substrate W is housed in a sealed chamber 101. A drying processing space 102 for performing a drying process on the substrate W is provided above the processing tank 100 in the sealed chamber 101.
[0003]
A processing liquid injection tube 103 is attached to the lower part of the processing tank 100. A processing liquid supply unit 105 is connected to the processing liquid injection pipe 103 via a pipe 104. The processing liquid supply unit 105 is configured to be able to selectively switch and supply a chemical liquid and pure water to the processing liquid injection pipe 103. Thereby, the chemical solution and the pure water are selectively switched and supplied to the treatment tank 100 from the treatment liquid injection pipe 103 at the bottom of the tank.
[0004]
Further, a liquid (chemical solution or pure water) supplied from the lower part of the tank and overflowing from the upper part of the tank flows into the sealed chamber 101, and is opened and closed from a drain / exhaust port 106 provided at the bottom of the sealed chamber 101. The liquid is drained to the drainage drain 109 through the pipe 108 in which 107 is interposed. A drainage port 110 is provided at the bottom of the treatment tank 100. The drainage port 110 is connected to a drainage drain 109 through a pipe 112 having an on-off valve 111 interposed therein. By switching the on-off valve 111 to open, the liquid in the processing tank 100 is removed. It is configured so that it can be discharged from the bottom.
[0005]
In the sealed chamber 101, a nozzle 113 for ejecting an organic solvent or the like is provided. Further, the drainage / exhaust port 106 is also connected to a vacuum suction source 116 via a pipe 115 having an on-off valve 114 interposed therein, so that the inside of the sealed chamber 101 can be decompressed by sucking the gas in the sealed chamber 101. doing.
[0006]
In the sealed chamber 101, there is also provided a substrate support member 117 that can be moved up and down to support a plurality of substrates W aligned at a predetermined interval.
[0007]
The cleaning / drying process by the conventional apparatus having the above-described configuration is performed as follows.
The pure water is supplied from the treatment liquid injection pipe 103 into the treatment tank 100, the pure water is filled in the treatment tank 100, and the ascending liquid flow of pure water is formed, and is supported by the substrate support member 117. In the state in which the substrate W is immersed (solid line in FIG. 13), the liquid supplied from the processing liquid injection tube 103 into the processing tank 100 is switched from pure water to a chemical solution (for example, hydrofluoric acid), and the processing tank A rising liquid flow of the chemical solution is formed in 100 to replace the liquid in the treatment tank 100 from pure water to the chemical solution, and chemical treatment is performed.
[0008]
When the chemical liquid processing is finished, pure water is supplied from the processing liquid injection pipe 103 into the processing tank 100, an ascending liquid flow of pure water is formed in the processing tank 100, and the liquid in the processing tank 100 is converted from the chemical liquid to the pure water. And the pure water washing process is performed.
[0009]
In the treatment tank 100, the chemical treatment and the pure water cleaning treatment are performed once or more. When the final pure water cleaning process is completed, the organic solvent is ejected from the nozzle 113 into the sealed chamber 101, and the substrate support member 117 is raised in a state where an ascending liquid flow of pure water is formed. The substrate W is pulled up from within 100 pure water. During the pulling up of the substrate W, the organic solvent is dissolved in the pure water at the gas-liquid interface, and the surface tension of the pure water is reduced just before coming out of the liquid surface on the surface of the substrate W, so that the substrate is almost drained. W is raised from pure water. Then, as shown by a two-dot chain line in FIG. 13, drying of the substrate W can be promoted by positioning the substrate W in the drying processing space 102 in the sealed chamber 101 and reducing the pressure in the sealed chamber 101. When the pressure in the sealed chamber 101 is reduced, the supply of pure water from the processing liquid injection tube 103 into the processing tank 100 is stopped and the on-off valve 111 is switched to open before the pressure reduction. The pure water inside is discharged from the bottom of the treatment tank 100 to the drainage drain 109.
[0010]
[Problems to be solved by the invention]
However, the conventional example having such a configuration has the following problems.
In the conventional apparatus, when liquid (pure water or chemical solution) overflows from the upper part of the processing tank 100, the on-off valve 107 is switched to open, and the liquid that has flowed into the sealed chamber 101 from the upper part of the processing tank 100. Is discharged from the drainage / exhaust port 106 at the bottom of the sealed chamber 101 to the drainage drain 109, but the liquid that has flowed into the sealed chamber 101, particularly the chemical solution, adheres to the inner wall surface of the sealed chamber 101. It is inevitable that it remains.
[0011]
As a result, the chemical solution remaining on the inner wall surface of the sealed chamber 101 is vaporized and drifts into the sealed chamber 101, and the chemical solution is reattached to the substrate W during the drying process, thereby reducing the cleanliness of the finished cleaning / drying process. There was a problem. For example, in an apparatus that performs a chemical treatment using hydrofluoric acid as a chemical solution on a silicon wafer as the substrate W, the hydrofluoric acid is reattached to the silicon wafer during the drying process, and then the silicon wafer is oxidized. Become. In particular, when the pressure in the sealed chamber 101 is reduced during the drying process, the chemical solution remaining on the inner wall surface of the sealed chamber 101 is more easily vaporized, and the chemical solution is more easily reattached to the substrate W.
[0012]
Further, in an apparatus that performs chemical processing using a plurality of types of chemical solutions, various chemical solutions are successively flowed into the sealed chamber 101 from the upper part of the processing tank 100, so that the chemical solutions that remain attached to the inner wall surface of the sealed chamber 101. Then, it may happen that another type of chemical liquid that has flowed into the sealed chamber 101 from the upper part of the processing tank 100 comes into contact therewith. As a result, there has been a problem that various chemical solutions cause a chemical reaction in the sealed chamber 101, resulting in generation of particles and contamination of the substrate W in the sealed chamber 101.
[0013]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a substrate processing apparatus capable of preventing reattachment of a chemical solution to a substrate and contamination of the substrate in a sealed chamber.
[0014]
[Means for Solving the Problems]
In order to achieve such an object, the present invention has the following configuration.
That is, according to the first aspect of the present invention, a treatment tank configured to selectively supply a chemical solution and pure water from the lower portion of the tank is accommodated in a sealed chamber. In the substrate processing apparatus for performing a water cleaning process and performing a drying process for drying the substrate in the sealed chamber after the pure water cleaning process in the processing tank, the liquid overflowing from the upper part of the processing tank is received. The recovery unit that collects the liquid and the liquid recovered by the recovery unit is discharged out of the sealed chamber.PipingWhen,A flow rate adjusting valve that is provided in the pipe and adjusts the amount of liquid discharged from the recovery unit, and recovers the chemical in the recovery unit while keeping the chemical in the recovery unit at a predetermined liquid level.When recovering pure water in the recovery unit after recovering the chemical solution in the recovery unit, the liquid level in the recovery unit of pure water recovered in the recovery unit is recovered for a predetermined period, and the chemical solution is recovered in the recovery unit So that it is higher than the liquid level of the chemical in the recovery unitThe flow control valveLiquid level control means for controlling.
[0015]
(Delete)
[0016]
[Action]
The operation of the first aspect of the invention is as follows.
When processing in the processing tank, the liquid (pure water or chemical liquid) supplied from the lower part of the processing tank and overflowing from the upper part of the processing tank is received and recovered by the recovery unit,PipingIs discharged out of the sealed chamber. Therefore, the chemical solution overflowing from the upper part of the processing tank is touched only by the recovery unit in the sealed chamber.
[0017]
Since the pure water washing process is performed after the chemical solution treatment in the treatment tank, the collection unit collects the pure water after collecting the chemical solution. Then, the liquid level control means, when collecting the pure water in the collecting unit after collecting the chemical solution in the collecting unit, sets the liquid level in the collecting unit of the pure water collected in the collecting unit for a predetermined period. Thus, the liquid level is controlled to be higher than the liquid level of the chemical liquid in the collection unit when the chemical liquid is collected. As a result, when the chemical solution is collected by the recovery unit, the chemical solution that adheres to the recovery unit at a height that is less than or equal to the liquid level of the chemical solution in the recovery unit is recovered at a liquid level higher than the liquid level of the chemical solution. It is washed away with pure water collected. Moreover, since the last process performed with a processing tank is a pure water washing process, a recovery part will collect | recover pure water finally. Therefore, in the sealed chamber, the chemical liquid does not remain and remains in the collecting portion, which is the only member touched by the chemical liquid overflowing from the upper part of the processing tank. As a result, the vaporized chemical liquid does not drift in the sealed chamber, and the chemical liquid can be prevented from re-adhering to the substrate. The generation of particles due to contact with each other is eliminated, and contamination of the substrate can be prevented.
[0018]
(Delete)
[0019]
(Delete)
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing the overall configuration of a substrate processing apparatus according to a first embodiment of the present invention, FIG. 2 is a plan view showing the configuration of a processing tank, and FIG. 3 is a main part of the apparatus of the first embodiment. It is an expanded sectional view.
[0021]
The substrate processing apparatus according to the first embodiment is configured such that a processing tank 1 that performs chemical liquid processing and pure water cleaning processing on a substrate W is housed in a sealed chamber 2. A drying processing space 3 for performing a drying process on the substrate W is provided above the processing tank 1 in the sealed chamber 2.
[0022]
A treatment liquid injection tube 4 is attached to the lower part of the treatment tank 1. The treatment liquid injection tube 4 is closed at the distal end, and has a large number of treatment liquid ejection holes 4a provided in parallel on the side surface so that the liquid introduced from the base end part 4b is ejected from each treatment liquid ejection hole 4a. It is configured. The treatment liquid injection pipe 4 is attached to the treatment tank 1 so that these treatment liquid ejection holes 4 a face the treatment tank 1. A processing liquid supply unit 6 is connected to the base end 4 b of the processing liquid injection pipe 4 via a pipe 5. The processing liquid supply unit 6 is configured to be able to selectively switch and supply pure water and one or more kinds of chemical liquids to the base end part 4 b of the processing liquid injection pipe 4. As a result, the chemical liquid and pure water are selectively switched and supplied to the treatment tank 1 from the treatment liquid ejection holes 4a of the treatment liquid injection pipe 4 at the bottom of the tank.
[0023]
A member 7 having a bottom surface and a side surface is joined to the upper outer periphery of the processing tank 1, and the member 7 and the outer peripheral wall 1 a of the processing tank 1 work together to overflow from the upper part of the processing tank 1. An overflow tank 8 is formed as a collection unit for receiving and collecting the liquid (chemical solution or pure water) that has come out. A discharge port (not shown) is provided at the bottom of the overflow tank 8, and this discharge port is connected to a drainage drain 10 outside the sealed chamber 2 via a pipe 9, and the liquid recovered in the overflow tank 8 is discharged from the sealed chamber 2. The drainage drain 10 can be discharged. In addition, the piping 9 and the drainage drain 10 comprise the discharge means in this invention.
[0024]
The pipe 9 is provided with a flow rate adjusting valve 20 that appropriately adjusts the amount of liquid discharged from the overflow tank 8. As this flow control valve 20, for example, a valve that operates with compressed air disclosed in Japanese Patent Application No. 3-93634 proposed by the present applicant, an appropriate electromagnetic flow control valve, or the like can be used. .
[0025]
In addition, a liquid level detection sensor 21 that detects the liquid level of the liquid in the overflow tank 8 is provided near the overflow tank 8. The liquid level detection sensor 21 includes an inert gas ejection pipe 22 and a micro pressure gauge 23. The tip of the inert gas ejection pipe 22 is introduced into the overflow tank 8. The micro pressure gauge 23 supplies an inert gas, such as a very small amount of nitrogen gas, to the inert gas ejection pipe 22 and discharges bubbles of the inert gas from the tip of the inert gas ejection pipe 22, and the inert gas at this time By detecting the discharge pressure of the inert gas from the ejection pipe 22, the liquid level of the current liquid (chemical liquid or pure water) in the overflow tank 8 is detected.
[0026]
A drainage port 11 is provided at the bottom of the processing tank 1. The drainage port 11 is connected to a drainage drain 10 through a pipe 13 having an on-off valve 12 interposed therein. By switching the on-off valve 12 to open, the liquid in the processing tank 1 is supplied to the processing tank 1. It is configured so that it can be discharged from the bottom.
[0027]
The sealed chamber 2 includes a main body 2a and a lid 2b configured to be openable and closable with respect to the main body 2a. When the substrate W is taken in and out of the sealed chamber 2 (main body 2a) with the lid 2b opened with respect to the main body 2a, and the lid 2b is closed with respect to the main body 2a. In addition, the inside of the sealed chamber 2 is configured to be in a sealed state.
[0028]
In the sealed chamber 2, a nozzle 30 for ejecting an organic solvent such as IPA (isopropyl alcohol) and an inert gas such as nitrogen gas is provided. An inert gas / organic solvent supply unit 32 is connected to the nozzle 30 via a pipe 31. The inert gas / organic solvent supply unit 32 supplies the heated and vaporized organic solvent to the nozzle 30 using an inert gas such as nitrogen gas as a carrier, and supplies only the inert gas used as the carrier to the nozzle 30. The organic solvent and the inert gas can be selectively switched and supplied from the nozzle 30 into the sealed chamber 2.
[0029]
An exhaust port 40 is provided at the bottom of the sealed chamber 2. The exhaust port 40 is connected to a vacuum suction source 43 via a pipe 42 provided with an on-off valve 41, and is configured so that the gas in the sealed chamber 2 can be sucked to depressurize the sealed chamber 2.
[0030]
A substrate support member 50 that supports a plurality of substrates W aligned at a predetermined interval is provided in the sealed chamber 2. The substrate support member 50 is connected to an elevating mechanism 52 that uses an air cylinder or the like as a drive source via a connecting member 51, and can be moved up and down by the elevating mechanism 52.
[0031]
The controller 60 controls switching supply of chemical liquid and pure water from the processing liquid supply unit 6 to the processing liquid injection pipe 4 and stopping supply of the chemical liquid and pure water (control of supply of chemical liquid and pure water to the processing tank 1). , Switching supply of the organic solvent and the inert gas from the organic solvent supply unit 32 to the nozzle 30 and control of stopping the supply of the organic solvent and the inert gas (supply control of the organic solvent and the inert gas into the sealed chamber 2) ), Control of opening / closing of the on-off valves 12 and 41, control of raising and lowering of the substrate support member 50, control of the overall level of the chemical and pure water collected in the overflow tank 8, etc. Perform the process.
[0032]
The liquid level control of the chemical solution or pure water recovered in the overflow tank 8 is based on the detection data from the liquid level detection sensor 21 while controlling the flow rate adjusting valve 20 to adjust the amount of liquid discharged from the overflow tank 8. As will be described later, when the pure water is collected in the overflow tank 8 after the chemical solution is collected in the overflow tank 8, the liquid level in the overflow tank 8 collected in the overflow tank 8 is set to DWL for a predetermined period. Maintained and controlled to be higher than the liquid level MQL of the chemical in the overflow tank 8 when the chemical is recovered in the overflow tank 8It is.
[0033]
Further, the controller 60 has a built-in timer 61 to manage the chemical liquid processing, the pure water cleaning processing, the drying processing, the timing control at the time of changing the liquid level of the liquid in the overflow tank 8, and the like. ing.
[0034]
Next, the cleaning / drying process performed by the first embodiment apparatus having the above-described configuration will be described with reference to the time charts shown in FIGS.
[0035]
In addition, each code | symbol in FIG. 4, FIG. 5 is as follows.
MQP: Chemical solution treatment.
DWP: pure water cleaning treatment.
DP: Drying process.
CP (DW / MQ): A process of replacing the liquid in the processing tank 1 from pure water with a chemical liquid.
CP (MQ / DW): A process of replacing the liquid in the treatment tank 1 from chemical liquid to pure water.
T1: CP (DW / MQ) start timing (start timing for switching the liquid supplied into the treatment tank 1 from pure water to chemical).
T2: CP (DW / MQ) completion timing (MQP start timing).
T3: CP (MQ / DW) start timing (start timing for switching the liquid supplied into the processing tank 1 from chemical to pure water).
T4: CP (MQ / DW) completion timing (DWP start timing).
t1: Time required for CP (DW / MQ).
t2: Time required for CP (MQ / DW).
t3: Time required for the liquid level in the overflow tank 8 to drop from DWL to MQL.
t4: Time required for the liquid level in the overflow tank 8 to rise from 0 level to MQL.
[0036]
Each of the above times 1, t2, t3, and t4 can be experimentally obtained in advance. Therefore, the controller 60 can grasp T2 based on T1 and t1 using the timer 61, can grasp T4 based on T3 and t2, and can overflow from the overflow tank on the basis of T1 based on T3. It is possible to determine the start of control for lowering the liquid level in the liquid 8 from DWL to MQL.
[0037]
In the cleaning / drying process, first, the lid 2b of the sealed chamber 2 is opened, and a plurality of substrates W are delivered from a substrate transport device (not shown) to the substrate support member 50 that is raised to the drying processing position 3. When the delivery of W is finished, the lid 2b is closed.
[0038]
Next, pure water is supplied from the treatment liquid injection pipe 4 into the treatment tank 1, the pure water is filled in the treatment tank 1, and a rising liquid flow of pure water is formed in the treatment tank 1. The substrate support member 50 is lowered and the substrate W is immersed together with the substrate support member 50 in the rising liquid flow of pure water. Alternatively, after the substrate support member 50 is lowered and the substrate W together with the substrate support member 50 is put into the processing tank 1, pure water is supplied from the processing liquid injection pipe 4 into the processing tank 1, and the inside of the processing tank 1 As the pure water is filled, a rising liquid flow of pure water is formed in the treatment tank 1.
[0039]
At this time, the pure water overflowing from the upper part of the treatment tank 1 is received and collected by the overflow tank 8 and discharged to the drainage drain 10. At this time, the controller 60 only needs to control so that the pure water recovered in the overflow tank 8 does not overflow from the overflow tank 8. Even if the liquid level is maintained at DWL, the controller 60 maintains the MQL. Alternatively, control may be performed so that the pure water to be recovered is maintained at an appropriate liquid level that does not overflow from the overflow tank 8. Furthermore, the amount of pure water discharged from the overflow tank 8 is made larger than the amount of pure water to be recovered, that is, the amount of pure water inflowing from the upper part of the processing tank 1 into the overflow tank 8. It may be adjusted so that the pure water does not accumulate in the overflow tank 8 and the pure water flowing into the overflow tank 8 is maintained at the liquid level discharged from the overflow tank 8 one after another.
[0040]
In this way, the pure water is supplied from the processing liquid injection pipe 4 into the processing tank 1 and the processing tank 1 is filled with pure water, and the rising liquid flow of pure water is formed. In a state where the substrate W supported by the member 50 is immersed (state of the solid line in FIG. 1), the liquid supplied from the processing liquid injection tube 4 into the processing tank 1 is switched from pure water to a chemical liquid (for example, hydrofluoric acid). Then, an ascending liquid flow of the chemical solution is formed in the treatment tank 1 and the liquid in the treatment tank 1 is replaced with the chemical solution from the pure water to perform the chemical treatment.
[0041]
During the replacement of the pure water with the chemical solution, a liquid in which the chemical solution is gradually mixed with the pure water overflows from the upper portion of the treatment tank 1, and this liquid is also received and recovered by the overflow tank 8, and drained drain 10 To be discharged. During the chemical treatment, the chemical solution is continuously supplied from the treatment solution injection pipe 4 into the treatment tank 1, a new chemical solution is supplied from the lower part of the treatment tank 1, and the treated chemical solution is supplied from the upper part of the treatment tank 1. Since the chemical liquid treatment is performed while the chemical liquid in the processing tank 1 is replaced and overflowed, the chemical liquid overflows from the upper part of the processing tank 1 during the chemical liquid treatment, and this chemical liquid is also received by the overflow tank 8 and collected. , And drained to the drainage drain 10.
[0042]
At this time, the controller 60 controls so that the liquid level in the overflow tank 8 is lowered to MQL at the start of replacement of the pure water with the chemical liquid (T1). For example, when the pure water is supplied into the treatment tank 1 from the treatment liquid injection pipe 4 and the pure water is filled in the treatment tank 1, an overflow in a state where an ascending liquid flow of pure water is formed in the treatment tank 1. When the level of pure water in the tank 8 is maintained at DWL, the liquid level of the pure water in the overflow tank 8 is earlier than T1 by (t3 + α) (α is an appropriate time of 0 seconds or more). Control for lowering the surface level from DWL to MQL is started. If the level of pure water in the overflow tank 8 is maintained at 0 level, the level of pure water in the overflow tank 8 is changed from 0 level to MQL at a timing earlier than T1 by (t4 + α). Start rising control. By controlling in this way, when the chemical solution is recovered in the overflow tank 8, the liquid level of the liquid in the overflow tank 8 is MQL, and the liquid level of the liquid in the overflow tank 8 is MQL. In the state, the chemical solution can be collected in the overflow tank 8. Thereafter, the controller 60 maintains the liquid level of the liquid in the overflow tank 8 (chemical liquid recovered in the overflow tank 8) at MQL during the replacement of pure water with chemical liquid, chemical liquid processing, and replacement of chemical liquid with pure water. Control to do.
[0043]
When a predetermined chemical processing time elapses, the liquid supplied from the processing liquid injection pipe 4 into the processing tank 1 is switched from the chemical liquid to pure water, and an ascending liquid flow of pure water is formed in the processing tank 1 to form the processing tank 1. The liquid in the inside is replaced with a pure water, and a pure water cleaning process (a cleaning process for washing away the chemical liquid adhering to the substrate W) is performed for a predetermined pure water cleaning time.
[0044]
During the replacement of the chemical solution with pure water, the liquid that is gradually diluted with pure water overflows from the upper part of the treatment tank 1, but this liquid also overflows with the liquid level maintained at MQL. It is received and collected in the tank 8 and discharged to the drainage drain 10. Moreover, since the supply of pure water from the processing liquid injection pipe 4 into the processing tank 1 is continued during the pure water cleaning process, pure water overflows from the upper part of the processing tank 1 during the pure water cleaning process. The pure water is also received and recovered by the overflow tank 8 and discharged to the drainage drain 10. The controller 60 starts the control to raise the liquid level of the liquid in the overflow tank 8 from MQL to DWL at the timing (T4) when the replacement of the chemical liquid with pure water is completed. Control is performed so that the liquid level in the overflow tank 8 is maintained at DWL. When the replacement of the chemical liquid with pure water is completed, the liquid flowing from the upper part of the processing tank 1 into the overflow tank 8 is pure water only. Accordingly, by controlling the liquid level as described above, when pure water is recovered in the overflow tank 8 after recovering the chemical liquid in the overflow tank 8, the overflow of pure water recovered in the overflow tank 8 for a predetermined period of time. When the liquid level in the tank 8 is maintained at DWL and can be higher than the liquid level MQL of the chemical liquid in the overflow tank 8 when the chemical liquid is collected in the overflow tank 8, and when the chemical liquid is collected in the overflow tank 8 The chemical liquid adhered to the inner wall surface of the overflow tank 8 at a height corresponding to the liquid level MQL of the chemical liquid in the overflow tank 8 is recovered in the overflow tank 8 at a liquid level DWL higher than the liquid level MQL of the chemical liquid. Can be washed away with pure water.
[0045]
In the treatment tank 1, the chemical solution treatment and the pure water cleaning treatment are performed once or more. Even when the chemical solution treatment and the pure water cleaning treatment are performed twice or more, the chemical treatment, the pure water cleaning treatment, the chemical solution treatment, the pure water cleaning treatment, and so on are repeated. At the time of starting the second and subsequent chemical processing, pure water is supplied into the processing tank 1 from the processing liquid injection pipe 4 in the previous pure water cleaning process, and the processing tank 1 is filled with pure water. Since the ascending liquid flow of pure water is formed and is in the same state as the start time of the first chemical treatment, the same chemical control and pure water cleaning treatment for the second and subsequent rounds are also performed as described above. Done in In addition, since the liquid level of the pure water in the overflow tank 8 is maintained at DWL during the pure water cleaning process, in the second and subsequent replacements from pure water to chemicals, the start of the replacement (T1) Control for lowering the level of pure water in the overflow tank 8 from DWL to MQL is started at a timing earlier than (t3 + α). Further, when the chemical liquid treatment and the pure water cleaning process are performed twice or more, and different types of chemical liquids are used for each chemical liquid process, the chemical liquid used for each chemical liquid process is supplied from the processing liquid supply unit 6 to the processing liquid injection pipe 4. To be supplied.
[0046]
When the pure water cleaning process time for the last pure water cleaning process elapses, the substrate 30 is supplied with the organic solvent supplied from the nozzle 30 into the sealed chamber 2 and a pure liquid rising liquid flow is formed. To raise the substrate W from the pure water in the processing tank 1. During the pulling up of the substrate W, the organic solvent is dissolved in the pure water at the gas-liquid interface, and the surface tension of the pure water is reduced just before coming out of the liquid surface on the surface of the substrate W, so that the substrate is almost drained. W is raised from pure water. Then, as shown by a two-dot chain line in FIG. 1, the substrate W is positioned in the drying processing space 3 in the sealed chamber 2 to dry the substrate W. At this time, drying of the substrate W can be promoted by opening the on-off valve 41 and reducing the pressure in the sealed chamber 2. When the pressure in the sealed chamber 2 is reduced, the supply of pure water from the processing liquid injection pipe 4 to the processing tank 1 is stopped and the on-off valve 12 is switched to open before the pressure reduction. The pure water inside is discharged from the bottom of the processing tank 1 to the drainage drain 10, and when the discharge of pure water in the processing tank 1 is finished, the on-off valve 12 is switched to the closed state. Further, after the supply of pure water from the processing liquid injection pipe 4 into the processing tank 1 is stopped, the pure water does not flow into the overflow tank 8 from the upper part of the processing tank 1, so that the controller 60 The level of pure water is not controlled. As a result, all the pure water in the overflow tank 8 is discharged to the drainage drain 10. In addition, while decompressing the inside of the sealed chamber 2, the inert gas may be supplied from the nozzle 30 into the sealed chamber 2 with a supply amount smaller than the exhaust amount of the gas from the sealed chamber 2.
[0047]
When the inside of the sealed chamber 2 is depressurized after the elapse of a predetermined drying processing time, the on-off valve 41 is closed and an inert gas is supplied from the nozzle 30 into the sealed chamber 2 to normalize the inside of the sealed chamber 2. Return to. Then, the lid 2b of the sealed chamber 2 is opened, and a plurality of cleaned and dried substrates W supported by the substrate support member 50 raised to the drying processing position 3 by a substrate transfer device (not shown). It is taken out. Thereafter, the same processing is switched back, and cleaning / drying processing is successively performed on the group of substrates W.
[0048]
If the supply of pure water into the processing tank 1 is continued without reducing the pressure in the sealed chamber 2 during the drying process, the level of pure water in the overflow tank 8 is maintained at DWL even during the drying process. You may make it do. 4 and 5 show the case where the chemical treatment and the pure water cleaning treatment are performed twice or more, but when the chemical treatment and the pure water cleaning treatment are performed only once, the first pure water cleaning treatment is performed. Control as the final pure water cleaning process.
[0049]
As described above, according to the apparatus of the first embodiment, when processing is performed in the processing tank 1, liquid (pure water or chemical liquid) that is supplied from the lower part of the processing tank 1 and overflows from the upper part of the processing tank 1. Is collected in the overflow tank 8 and discharged to the drainage drain 10 outside the sealed chamber 2. Therefore, in the sealed chamber 2, the chemical solution overflowing from the upper part of the processing tank 1 is limited to the inner wall surface of the overflow tank 8. Then, when the controller 60 recovers the pure water in the overflow tank 8 after recovering the chemical in the overflow tank 8, the controller 60 determines the liquid level in the overflow tank 8 of pure water recovered in the overflow tank 8 for a predetermined period. Since it is controlled to be higher than the liquid level of the chemical liquid in the overflow tank 8 when the chemical liquid is collected in the overflow tank 8, it adheres to the inner wall surface of the overflow tank 8 when the chemical liquid is collected in the overflow tank 8. The chemical solution can be washed away with pure water collected in the overflow tank 8, and in the sealed chamber 2, the chemical solution remains attached to the overflow tank 8, which is the only member touched by the chemical liquid overflowing from the upper part of the processing tank 1. It will not be left behind. Therefore, the vaporized chemical liquid does not drift in the sealed chamber 2, and reattachment of the chemical liquid to the substrate W can be prevented regardless of whether or not the pressure in the sealed chamber 2 is reduced during the drying process. In addition, various chemical solutions do not come into contact in the overflow tank 8, and no particles are generated due to the various chemical solutions coming into contact, and contamination of the substrate W can be prevented.
[0050]
Since the chemical liquid does not flow into the overflow tank 8 immediately after the replacement of the pure water with the chemical liquid is started, the control for lowering the liquid level of the pure water in the overflow tank 8 from DWL to MQL is shown in the above figure. 4. You may make it start at a timing later than FIG. For example, when the time from the start of replacement of pure water to the chemical solution until the chemical solution flows into the overflow tank 8 is longer than t3, as shown in FIG. Control for lowering the level of pure water from DWL to MQL may be started at T1.
[0051]
Further, as shown in FIG. 6B, if the liquid level in the overflow tank 8 is raised from MQL to DWL after T4, the chemical liquid that adheres to the inner wall surface of the overflow tank 8 Since the height of the liquid can be reduced to DWL or less, control for increasing the liquid level in the overflow tank 8 from MQL to DWL is started at a timing earlier than T4 by β (however, 0 <β <t5). You may make it do. Note that t5 is a time required for the liquid level in the overflow tank 8 to rise from MQL to DWL, and can be experimentally obtained in advance.
[0052]
Further, when the chemical solution adhering to the inner wall surface of the overflow tank 8 can be washed out relatively quickly, as shown in each drawing of FIG. You may control to maintain the liquid level of a pure water at DWL.
[0053]
Further, the liquid level MQL of the chemical liquid recovered in the overflow tank 8 may be set to the O level.
[0054]
Further, as shown in FIGS. 8 and 9, at the final stage of maintaining the liquid level of the chemical in the overflow tank 8 at MQL by the control of FIGS. 4 and 5, the liquid level of the chemical in the overflow tank 8 is maintained. In the final stage of maintaining the liquid level of the pure water in the overflow tank 8 at DWL by the control of FIG. The liquid level may be controlled to be adjusted to a liquid level HL that is higher than DWL. By controlling in this way, it can be expected that the chemical solution is washed out more reliably with the recovered pure water.
[0055]
In addition, you may control the liquid level level of these overflow tanks 8 with the specific resistance value and chemical | medical solution concentration in a tank.
[0056]
next,According to reference examplesThe configuration of the apparatus will be described with reference to FIG. FIG.Reference exampleIt is a longitudinal cross-sectional view which shows the whole structure of the substrate processing apparatus which concerns on this.
[0057]
thisAccording to reference examplesThe apparatus omits the liquid level control of the liquid in the overflow tank 8 by the flow rate adjusting valve 20, the liquid level detection sensor 21, and the controller 60 of the first embodiment apparatus, and instead collects in the sealed chamber 2. A shower nozzle 70 as a part cleaning means is provided, and pure water as a cleaning liquid is jetted and supplied from the shower nozzle 70 toward the overflow tank 8, particularly the inner wall surface of the overflow tank 8, and the overflow tank 8 (inner wall surface thereof) And the chemical solution adhering to the overflow tank 8 is washed away.
[0058]
A pure water supply unit 72 is connected to the shower nozzle 70 via a pipe 71, and pure water is supplied from the pure water supply unit 72 to the shower nozzle 70 and stopped (control of pure water to the overflow tank 8 is ejected). The supply control is performed by the controller 60.
[0059]
Further, considering that pure water from the shower nozzle 70 is jetted onto the inner wall surface of the sealed chamber 2, the exhaust port 40 is used as a drain / exhaust port, and the drain / exhaust port 40 is connected to the on-off valve 44. Is connected to the drainage drain 10 via a pipe 45 in which is disposed, so that pure water sprayed from the shower nozzle 70 onto the inner wall surface of the sealed chamber 2 can be discharged to the drainage drain 10. Note that when the pure water ejected from the shower nozzle 70 is supplied only to the inner wall surface of the overflow tank 8 and is not sprayed to the inner wall surface of the sealed chamber 2, the on-off valve 44 and the piping 45 are omitted. Also good.
[0060]
Further, the liquid discharged from the overflow tank 8 to the drainage drain 10 is discharged so that the liquid (chemical solution or pure water) overflowing from the upper part of the processing tank 1 and recovered in the overflow tank 8 does not overflow from the overflow tank 8. The liquid volume is adjusted.
[0061]
thisAccording to reference examplesThe overall operation of the cleaning / drying process by the apparatus is the same as the operation described in the first embodiment. However, thisAccording to reference examplesIn the apparatus, instead of the liquid level control of the liquid in the overflow tank 8 performed in the apparatus of the first embodiment, a process of cleaning the inner wall surface of the overflow tank 8 with pure water ejected from the shower nozzle 70 is performed.
[0062]
The cleaning process of the inner wall surface of the overflow tank 8 with pure water from the shower nozzle 70 is, for example, after starting the replacement of pure water before the chemical process with the chemical liquid every time the chemical process and the pure water cleaning process are performed. The chemical solution used for each chemical treatment was collected in the overflow tank 8 by performing until the replacement of the chemical solution after the chemical treatment with pure water was completed (between T1 and T4 in FIGS. 4 and 5). Thereafter, the chemical solution can be prevented from remaining in the overflow tank 8.
[0063]
The controller 60 opens the on-off valve 44 when drain water is supplied from the shower nozzle 70 for the first time, and drains pure water sprayed from the shower nozzle 70 onto the inner wall surface of the sealed chamber 2. The drain 10 can be discharged.
[0064]
Like thisAccording to reference examplesAccording to the apparatus, the inner wall surface of the overflow tank 8 is washed with pure water jetted and supplied from the shower nozzle 70, so that the chemical solution adhering to the inner wall surface of the overflow tank 8 is completely washed away in the sealed chamber 2. Further, it is possible to prevent the chemical liquid from being left attached and remaining in the overflow tank 8 which is the only member touched by the chemical liquid overflowing from the upper part of the processing tank 1. Therefore, the vaporized chemical liquid does not drift in the sealed chamber 2, and reattachment of the chemical liquid to the substrate W can be prevented regardless of whether or not the pressure in the sealed chamber 2 is reduced during the drying process. In addition, various chemical solutions do not come into contact in the overflow tank 8, and no particles are generated due to the various chemical solutions coming into contact, and contamination of the substrate W can be prevented.
[0065]
As shown in FIG. 11, the features of the first embodiment andReference exampleThe liquid level control of the liquid in the overflow tank 8 described in the first embodiment and the aboveReference exampleThe chemical solution adhering to the overflow tank 8 may be washed away by combining the cleaning of the inner wall surface of the overflow tank 8 with pure water from the shower nozzle 70 described in the above.
[0066]
Further, in each of the above-described embodiments and modifications thereof, the treatment tank 1 to which the so-called single-pipe structure treatment liquid injection pipe 4 is attached is illustrated. However, as shown in FIG. The present invention can be similarly applied to a structure in which the outer tube 81 having the holes 80 arranged in parallel is further arranged on the outer periphery of the processing liquid injection tube 4 to have a double tube structure.
[0067]
【The invention's effect】
As is apparent from the above description, the claims1According to the described invention, the liquid overflowing from the upper part of the treatment tank is received and collected by the collection unit and is discharged outside the sealed chamber, so that the liquid overflowed from the upper part of the treatment tank in the sealed chamber. The member which a chemical solution touches can be limited to a collection part.
[0068]
And in invention of Claim 1, when collect | recovering pure water in a collection | recovery part after collect | recovering a chemical | medical solution in a collection | recovery part, the liquid level in the collection | recovery part of the pure water collect | recovered in a collection | recovery part for a predetermined period, Control was made to be higher than the liquid level of the chemical solution in the recovery unit when the recovery unit collects the chemical solution, so the chemical solution adhering to the recovery unit when the chemical solution was recovered was washed away with pure water recovered by the recovery unit. In other words, the chemical solution is not left on the collecting part while it is left attached. Therefore, the vaporized chemical solution does not drift in the sealed chamber, and the chemical solution can be prevented from re-adhering to the substrate. Generation of particles due to contact is eliminated, and contamination of the substrate can be prevented.
[0069]
(Delete)
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an overall configuration of a substrate processing apparatus according to a first embodiment of the present invention.
FIG. 2 is a plan view showing a configuration of a processing tank.
FIG. 3 is an enlarged cross-sectional view of a main part of the apparatus according to the first embodiment.
FIG. 4 is a time chart showing liquid level control of the liquid in the overflow tank by the first embodiment device.
FIG. 5 is a time chart continued from FIG. 4;
FIG. 6 is a time chart showing a modification of the liquid level control of the liquid in the overflow tank by the first embodiment.
FIG. 7 is a time chart showing another modification of the liquid level control of the liquid in the overflow tank by the first embodiment.
FIG. 8 is a time chart showing still another modified example of the liquid level control of the liquid in the overflow tank by the first embodiment.
FIG. 9 is a time chart continued from FIG. 8;
FIG. 10Reference exampleIt is a longitudinal cross-sectional view which shows the whole structure of the substrate processing apparatus which concerns on this.
FIG. 11 shows the features of the first embodiment.Reference exampleIt is a longitudinal cross-sectional view which shows the whole structure of the modification which comprised both of these characteristics.
FIG. 12 is a longitudinal cross-sectional view showing a main configuration of a modified example of the processing tank, and a cross-sectional view showing configurations of a processing liquid injection pipe and an outer pipe.
FIG. 13 is a longitudinal sectional view showing an overall configuration of a conventional apparatus.
[Explanation of symbols]
1: Treatment tank
2: Sealed chamber
3: Drying treatment space
4: Treatment liquid injection tube
6: Treatment liquid supply unit
8: Overflow tank
10: Drainage drain
20: Flow control valve
21: Liquid level detection sensor
60: Controller
70: Shower nozzle
W: Substrate
MQL: Liquid level of the chemical in the overflow tank when collecting the chemical in the overflow tank
DWL: Level of pure water in the overflow tank when pure water is collected in the overflow tank

Claims (1)

A processing tank configured to be able to selectively switch and supply chemical liquid and pure water from the bottom of the tank is housed in a sealed chamber, and performs chemical liquid processing and pure water cleaning processing on the substrate in the processing tank, and the processing tank In the substrate processing apparatus for performing a drying process for drying the substrate in the sealed chamber after the pure water cleaning process in
A collection unit that receives and collects liquid overflowing from the upper part of the treatment tank;
A pipe for discharging the liquid recovered by the recovery unit to the outside of the sealed chamber;
A flow rate adjusting valve provided in the pipe for adjusting the amount of liquid discharged from the recovery unit;
The recovery unit collects the chemical solution while keeping the chemical solution in the recovery unit at a predetermined liquid level, and collects the chemical solution in the recovery unit and then collects pure water in the recovery unit for a predetermined period. A liquid that controls the flow rate control valve so that the liquid level in the recovery part of pure water recovered by the part is higher than the liquid level of the chemical liquid in the recovery part when the chemical liquid is recovered by the recovery part Surface level control means;
A substrate processing apparatus comprising:

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