Substrate processing apparatus

Abstract

This substrate processing apparatus is provided with: a processing chamber having an internal space capable of accommodating a substrate; a supply unit capable of supplying the processing fluid as a liquid; a heating unit for heating the liquid processing fluid supplied from the supply unit to a critical temperature or higher of the processing fluid and transferring the liquid processing fluid to a supercritical state; a flow path forming part forming a flow path of the processing fluid from the fluid supply part to the processing chamber through the heating part; a first filtration unit that is inserted in the flow path between the supply unit and the heating unit and filters the liquid treatment fluid; and a second filtration unit that is interposed in the flow path between the heating unit and the processing chamber and filters the processing fluid in the supercritical state.

Description

TECHNICAL FIELD

[0001] The present application relates to a technology of housing a substrate in a processing chamber to be processed with a processing fluid in a supercritical state. BACKGROUND

[0002] In a processing procedure of various substrates such as semiconductor substrates, glass substrates for display devices, and the like, a procedure of processing the front surface of a substrate with various processing fluids is included. A wet processing using a liquid such as a chemical solution or a cleaning solution as a processing fluid has been widely performed. In recent years, a processing using a processing fluid in a supercritical state has also been put into practical use in order to dry a substrate after the wet processing. In particular, in a drying processing of a substrate having a patterned surface in which a fine pattern is formed, a processing with a supercritical processing fluid is advantageous. This is because a processing fluid in a supercritical state has a property of entering a deep portion of a gap of a pattern due to a low surface tension compared to a liquid. By using the processing fluid, a drying processing can be efficiently performed. In addition, a risk of pattern collapse due to surface tension at the time of drying can be reduced.

[0003] For example, in a substrate processing apparatus described in Japanese Patent Application Publication No. 2023-036123 (Patent Literature 1), a substrate is housed in a processing chamber in a state of being placed on a flat plate-shaped support member. In the processing chamber, a processing fluid is introduced into a space on the upper side of the substrate and a space on the lower side of the support member, respectively, and a laminar flow of the processing fluid is formed in these spaces to process the substrate. In each of a pipe that supplies the processing fluid to the upper side of the substrate and a pipe that supplies the processing fluid to the lower side of the substrate, a filter that filters the processing fluid is interposed in order to remove a contaminant that can be contained in the processing fluid. SUMMARY

[0004] [PROBLEMS TO BE SOLVED BY THE INVENTION]

[0005] In a substrate processing technology that processes a substrate with a supercritical processing fluid, in a processing procedure thereof, generally, the processing fluid phase changes between several states such as a gas phase, a liquid phase, and a supercritical state. There are cases where such a phase change occurs in a pipe through which the processing fluid flows. On the other hand, the specification of a filter provided in a pipe system changes depending on whether a fluid that becomes a processing target is a gas or a liquid. That is, if the kind of a fluid that flows or the purpose of arrangement does not match the specification of the filter, sometimes, a desired filtering performance cannot be obtained. In addition, a problem that an excessive burden is applied to the filter or the pipe and adverse effects are caused to them can occur.

[0006] Therefore, it is important to configure what kind of filter at which position in the piping system for obtaining a good filtering result. However, in the conventional technology, this is not mentioned in detail. Thus, in the apparatus for performing processing using a supercritical processing fluid, regarding the configuration of the filter in the piping system, careful study is required. However, it cannot be said that the insight based on such a viewpoint is sufficiently accumulated, and establishment of a technology for optimizing the configuration of the filter is desired.

[0007] [Technical means for solving the problem]

[0008] The present application was made in view of the problem, and aims at proposing a preferred configuration of a filter on a flow path of a processing fluid in a technology of processing a substrate by a supercritical processing fluid.

[0009] One aspect of the present application is a substrate processing apparatus that processes a substrate by a processing fluid in a supercritical state, including: a processing chamber having an internal space capable of housing the substrate; a supply portion capable of supplying the processing fluid as a liquid; a heating portion that heats the processing fluid of the liquid supplied from the supply portion to a critical temperature or higher of the processing fluid to shift to a supercritical state; a flow path forming portion that forms a flow path of the processing fluid from the supply portion through the heating portion to the processing chamber; a first filter portion that filters the processing fluid of the liquid interposed in the flow path between the supply portion and the heating portion; and a second filter portion that filters the processing fluid in the supercritical state interposed in the flow path between the heating portion and the processing chamber.

[0010] In the application thus configured, the processing fluid supplied as a liquid from the supply portion is heated by the heating portion to be supercritical, and introduced into the processing chamber. Thereby, the processing fluid in the supercritical state is supplied to the processing chamber. Further, the first filter portion is provided in the flow path of the liquid from the supply portion to the heating portion. In addition, the second filter portion is provided in the flow path of the processing fluid in the supercritical state (hereinafter, sometimes simply referred to as "supercritical fluid") from the heating portion to the processing chamber.

[0011] Thus, regarding the flow path of the processing fluid, it is possible to explicitly divide the upstream side thereof as a region in which a liquid flows and the downstream side thereof as a region in which a supercritical fluid flows, with the heating portion therebetween. Further, by configuring the filter in each region, it is possible to apply a filter that focuses on the fluid to be processed. That is, it is possible to utilize a filter suitable for processing of a liquid to the first filter portion and a filter suitable for processing of a supercritical fluid to the second filter portion, respectively.

[0012] [Effects of the application]

[0013] As described above, according to the present application, the flow path through which the processing fluid is supplied to the processing chamber is clearly divided into a region of the processing liquid and a region of the processing supercritical fluid. Also, a filter is provided in each region. Therefore, by selecting a filter corresponding to the processing fluid, the performance thereof can be fully exhibited, and the substrate can be processed by the clean processing fluid from which contaminating substances have been removed.

[0014] The application will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Figure One The above and other objects and novel features of the present application will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which: BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 FIG. 1 is a diagram showing the schematic configuration of a substrate processing system of an embodiment of a substrate processing apparatus equipped with the present application.

[0016] Figure 2 FIG. 2 is a side view showing the entire configuration of a wet processing apparatus.

[0017] Figure 3 FIG. 3 is a diagram for explaining the operation of the wet processing apparatus.

[0018] Figure 4 FIG. 4 is a side view showing the configuration of a supercritical processing apparatus.

[0019] Figure 5 FIG. 5 is a diagram showing details of the supply and discharge paths of the processing fluid.

[0020] Figure 6 FIG. 6 is a flowchart showing the processing performed by the supercritical processing apparatus.

[0021] Figure 7 FIG. 7 is a diagram showing the change in pressure in the processing chamber and the reservoir.

[0022] Figure 8 FIG. 8 is a diagram showing a second embodiment of the substrate processing apparatus.

[0023] Figure 9 FIG. 9 is a diagram showing a third embodiment of the substrate processing apparatus.

[0024] Figure 10 FIG. 10 is a diagram showing a fourth embodiment of the substrate processing apparatus. DETAILED DESCRIPTION

[0025] <First Embodiment>

[0026] Figure 1is a view showing a schematic configuration of a substrate processing system equipped with a substrate processing apparatus according to the first embodiment of the present application. The substrate processing system 1 is, for example, a processing system for supplying a processing liquid to an upper surface of a substrate such as a semiconductor wafer, wet processing the substrate, and then drying the substrate. The substrate processing system 1 has a system configuration suitable for implementing the substrate processing method according to the present application. The substrate processing system 1 includes a wet processing apparatus 2, a substrate conveyance apparatus 3, a supercritical processing apparatus 4, and a control apparatus 9 as its main components.

[0027] The wet processing apparatus 2 receives a substrate to be processed and performs a prescribed wet processing. The processing content is not particularly limited. The wet processing includes a development processing or a cleaning processing, but after the development processing or the like, a liquid- filled state in which an organic solvent such as an IPA (Iso-Propyl Alcohol) liquid is filled on a pattern formation surface of the substrate is formed. The substrate conveyance apparatus 3 conveys the substrate out of the wet processing apparatus 2 while maintaining the liquid-filled state and conveys the substrate into the supercritical processing apparatus 4. The supercritical processing apparatus 4 corresponds to the substrate processing apparatus according to the present application and performs a drying processing (supercritical drying processing) using a processing fluid in a supercritical state on the substrate conveyed in. These apparatuses are disposed in a clean room. Therefore, the substrate conveyance apparatus 3 conveys the substrate in an atmospheric atmosphere and an atmospheric pressure.

[0028] The control apparatus 9 controls the operations of the respective apparatuses and realizes a prescribed processing. For the purpose, the control apparatus 9 includes a CPU (Central Processing Unit) 91, a memory 92, a storage 93, an interface 94, and the like. The CPU 91 executes various control programs. The memory 92 temporarily stores processing data. The storage 93 stores the control programs executed by the CPU 91. The interface 94 exchanges information with a user or an external apparatus. The operations of the apparatuses described later are realized by the CPU 91 executing the control programs written in advance into the storage 93 so that the respective parts of the apparatuses perform prescribed operations.

[0029] The control apparatus 9 realizes, as functional blocks, a wet processing control section 95 that controls the operation of the wet processing apparatus 2, a conveyance control section 96 that controls the operation of the substrate conveyance apparatus 3, a supercritical processing control section 97 that controls the operation of the supercritical processing apparatus 4, and the like by the CPU 91 executing prescribed control programs. In addition, at least a part of each of the functional blocks can be configured by a dedicated software.

[0030] As the "substrate" in the present embodiment, various substrates such as a semiconductor wafer, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a glass substrate for a plasma display, a substrate for a FED (Field Emission Display), a substrate for an optical disc, a substrate for a magnetic disc, and a substrate for a magneto-optical disc can be applied. Hereinafter, a substrate processing apparatus for processing a disc-shaped semiconductor wafer will be mainly described with reference to the drawings. However, the present embodiment can also be applied to processing of the various substrates exemplified above. In addition, various shapes can be applied to the shape of the substrate.

[0031] In addition, in the following description, a substrate in which a pattern is formed on only one main surface will be exemplified. Here, the main surface on which a pattern or the like is formed will be referred to as the "front surface", and the main surface on the opposite side thereof on which no pattern is formed will be referred to as the "back surface". In addition, the main surface of the substrate facing downward will be referred to as the "lower surface", and the main surface of the substrate facing upward will be referred to as the "upper surface". Hereinafter, the upper surface will be described as the front surface.

[0032] Figure 2 and Figure 3 is a view showing a configuration example of a wet processing apparatus. More specifically, Figure 2 is a side view showing the entire configuration of the wet processing apparatus, Figure 3 is a view for explaining the operation of the wet processing apparatus. The wet processing apparatus 2 is an apparatus that processes a substrate S by supplying a processing liquid to the upper surface of the substrate S. The operation of the wet processing apparatus 2 is controlled by the wet processing control section 95 of the control apparatus 9.

[0033] The wet processing apparatus 2 supplies a processing liquid to the front surface (pattern formation surface) Sa of the substrate S, and performs wet processing such as front surface processing or cleaning of the substrate S. For this purpose, the wet processing apparatus 2 has a substrate holding section 21, a splash guard 22, and processing liquid supply sections 23 and 24 inside a processing chamber 200. These operations are controlled by the wet processing control section 95 provided in the control apparatus 9. The substrate holding section 21 has a circular plate-shaped spin chuck 211 having substantially the same diameter as the substrate S, and a plurality of chuck pins 212 are provided at the peripheral portion of the spin chuck 211. The substrate S is supported by the chuck pins 212 abutting against the peripheral portion of the substrate S, and the spin chuck 211 can hold the substrate S in a horizontal posture in a state in which the upper surface of the substrate S is separated.

[0034] The rotary chuck 211 is supported in a manner that the upper surface thereof becomes horizontal by a rotary support shaft 213 extending downward from the center portion of the lower surface thereof. The rotary support shaft 213 is rotatably supported by a rotary mechanism 214 installed at the bottom of the processing chamber 200. The rotary mechanism 214 has a rotary motor not shown therein. The rotary chuck 211 directly coupled to the rotary support shaft 213 is rotated about the rotary axis AX shown by a one-dot chain line by the rotation of the rotary motor according to a control command from the control device 9. Figure 2 The substrate S is rotated about the rotary axis AX in a horizontal posture.

[0035] A splash guard 22 is provided in a manner that the substrate holding portion 21 is surrounded from the side. The splash guard 22 has a substantially cylindrical cup 221 provided in a manner that the peripheral portion of the rotary chuck 211 is covered, and a liquid receiving portion 222 provided at the lower portion of the outer peripheral portion of the cup 221. The cup 221 is raised and lowered according to a control command from the control device 9. The cup 221 is moved up and down between a lower position shown in Figure 2 and an upper position shown in Figure 3 The lower position is a position where the upper end portion of the cup 221 is lowered below the peripheral portion of the substrate S held on the rotary chuck 211. The upper position is a position where the upper end portion of the cup 221 is positioned above the peripheral portion of the substrate S.

[0036] When the cup 221 is positioned at the lower position, the substrate S held on the rotary chuck 211 is exposed to the outside of the cup 221 as shown in Figure 2 Therefore, for example, the cup 221 does not become an obstacle when the substrate S is carried into and out of the rotary chuck 211.

[0037] When the cup 221 is positioned at the upper position, the peripheral portion of the substrate S held on the rotary chuck 211 is surrounded as shown in Figure 3 Therefore, the processing liquid splashed from the peripheral portion of the substrate S is prevented from flying into the chamber 200 during the liquid supply described later, and the processing liquid can be surely recovered. That is, the droplets of the processing liquid splashed from the peripheral portion of the substrate S by the rotation of the substrate S adhere to the inner wall of the cup 221, flow downward, and are collected and recovered by the liquid receiving portion 222 provided at the lower portion of the cup 221. In order to individually recover a plurality of processing liquids, a plurality of cups can be concentrically provided.

[0038] The processing liquid supply portion 23 has a configuration in which a rotary support shaft 232 is rotatably provided with respect to a base 231 fixed to the processing chamber 200, and a nozzle 234 is installed at the front end of an arm 233 extending horizontally from the rotary support shaft 232. The arm 233 is swung by the rotation of the rotary support shaft 232 according to a control command from the control device 9. Therefore, the nozzle 234 at the front end of the arm 233 is retracted from the upper direction of the substrate S to a retracted position shown in Figure 2 and is projected to a projection position shown inFigure 3 moves between the processing positions above the substrate S.

[0039] The nozzle 234 is connected to a processing liquid supply source 238, and when an appropriate processing liquid is sent from the processing liquid supply source 238, the processing liquid is sprayed from the nozzle 234 toward the substrate S. As shown in the figure, while the substrate S is rotated by the spin chuck 211 at a relatively low speed, the processing liquid Ll is supplied from the nozzle 234 positioned above the center of rotation of the substrate S. In this way, the front surface Sa of the substrate S is processed by the processing liquid Ll. As the processing liquid Ll, a liquid having various functions such as a developing liquid, an etching liquid, a cleaning liquid, a rinsing liquid, and the like can be used, and the composition thereof is arbitrary. Furthermore, processing can also be performed by combining a plurality of processing liquids. Figure 3

[0040] The other group of processing liquid supply sections 24 also has a configuration corresponding to the first processing liquid supply section 23. That is, the second processing liquid supply section 24 has a base 241, a rotating shaft 242, an arm 243, and a nozzle 244, and the like. The configurations of these are the same as the corresponding configurations in the first processing liquid supply section 23. The arm 243 swings by the rotating shaft 242 rotating in accordance with a control command from the control device 9. The nozzle 244 at the front end of the arm 243 supplies a processing liquid to the front surface Sa of the substrate S.

[0041] In the embodiment, the second processing liquid supply section 24 is used for the purpose of forming a liquid film for preventing drying on the substrate S after wet processing. That is, the substrate S after wet processing is carried to the supercritical processing device 4 and subjected to supercritical drying processing. At this time, in order to prevent the front surface of the substrate S from being oxidized or a fine pattern formed on the front surface from collapsing during the carrying, the substrate S is carried in a state in which the front surface is covered with a paddle-shaped liquid film.

[0042] As the liquid constituting the liquid film, a main component of a processing liquid used for rinsing processing, that is, a substance having a surface tension smaller than water, such as an organic solvent such as isopropyl alcohol (IPA) or acetone, is used. These organic solvents are supplied from an organic solvent supply source 248.

[0043] Here, two groups of processing liquid supply sections are provided in the wet processing device 2, but the number of processing liquid supply sections provided or the configuration or function thereof is not limited to this. For example, the processing liquid supply sections can be only one group, and furthermore, three or more groups can be provided. Furthermore, one processing liquid supply section can have a plurality of nozzles. For example, a plurality of nozzles can be provided at the front end of one arm. Furthermore, not only aspects in which the nozzles as described above spray a processing liquid in a state in which they are positioned at a prescribed position, but also aspects in which, for example, the nozzles spray a processing liquid while scanning and moving along the front surface Sa of the substrate S can be included.

[0044] Returning to Figure 1 ​Continuing the explanation. The substrate conveyance device 3 is provided with a conveyance robot 30 in which a hand 31 is provided at the tip of an arm that is capable of extending and retracting and rotating freely. The hand 31 is capable of supporting a substrate by coming into contact with the lower surface portion of the substrate, as shown in Figure 1 The substrate conveyance device 3 is capable of moving in and out with respect to both the wet processing device 2 and the supercritical processing device 4, as shown by the dotted line. As a result, the substrate can be conveyed in and out of each of the wet processing device 2 and the supercritical processing device 4. The operation of the conveyance robot 30 is controlled by a conveyance control section 96 of the control device 9. There are many well-known technologies for such conveyance robots, and since these technologies can be appropriately selected for use in the present embodiment, a detailed explanation will be omitted.

[0045] Figure 4 is a side view showing the configuration of the supercritical processing device. The supercritical processing device 4 corresponds to the first embodiment of the substrate processing device of the present application, and is a device that performs drying processing on a substrate S after wet processing using a processing fluid in a supercritical state. More specifically, the supercritical processing device 4 is a device that receives a substrate S after wet processing, replaces the liquid remaining on the substrate S with a processing fluid in a supercritical state, and then discharges the processing fluid, thereby bringing the substrate S to a final dry state.

[0046] The supercritical processing device 4 is provided with a processing unit 41, a transfer unit 43, and a supply unit 45. The processing unit 41 is the main body that performs supercritical drying processing. The transfer unit 43 receives a substrate S after wet processing that is conveyed by the substrate conveyance device 3, and conveys it into the processing unit 41. In addition, the processed substrate S is handed over from the processing unit 41 to an external conveyance device. The supply unit 45 supplies chemicals, power, and energy, etc. required for processing to the processing unit 41 and the transfer unit 43. These operations are controlled by the control device 9, particularly a supercritical processing control section 97.

[0047] The processing unit 41 has a configuration in which a processing chamber 412 is mounted on a pedestal 411. The processing chamber 412 is composed of a combination of several metal blocks, and has an internal cavity that constitutes a processing space SP. A substrate S that is the object of processing is conveyed into the processing space SP, and receives processing. On the (-Y) side surface of the processing chamber 412, a slit-shaped opening 421 is formed that extends long in the X direction. The processing space SP is in communication with the outside space via the opening 421. The cross-sectional shape of the processing space SP is substantially the same as the opening shape of the opening 421. That is, the processing space SP is a cavity that extends in the Y direction, and has a cross-sectional shape that is longer in the X direction and shorter in the Z direction.

[0048] On the (-Y) side of the processing chamber 412, a lid member 413 is provided so as to occlude the opening 421. By occluding the opening 421 of the processing chamber 412 with the lid member 413, a gas-tight processing container is constituted. Thus, processing of the substrate S at high pressure can be performed in the internal processing space SP. On the (+Y) side of the lid member 413, a flat plate-shaped support tray 415 is installed in a horizontal posture. The upper surface of the support tray 415 becomes a support surface on which the substrate S can be placed. The lid member 413 is supported so as to be movable in the Y direction by a support mechanism, which is not shown.

[0049] The lid member 413 is movable in and out with respect to the processing chamber 412 by a feed and withdrawal mechanism 453 provided in the supply unit 45. Specifically, the feed and withdrawal mechanism 453 has, for example, a linear motor, a direct-acting guide, a ball screw mechanism, a solenoid, or a cylinder, or the like direct-acting mechanism. This direct-acting mechanism moves the lid member 413 in the Y direction. The feed and withdrawal mechanism 453 is actuated in accordance with a control command from the control device 9.

[0050] The lid member 413 is moved in the (-Y) direction to be away from the processing chamber 412. As shown by the broken line, when the support tray 415 is pulled out to the outside from the processing space SP via the opening 421, the support tray 415 can be accessed. That is, the placement of the substrate S on the support tray 415 and the extraction of the substrate S placed on the support tray 415 can be performed. On the other hand, by moving the lid member 413 in the (+Y) direction, the support tray 415 is housed in the processing space SP. In the case where the support tray 415 has the substrate S placed thereon, the substrate S is carried into the processing space SP together with the support tray 415.

[0051] By moving the lid member 413 in the (+Y) direction, the opening 421 is covered and the processing space SP is sealed. Between the (+Y) side of the lid member 413 and the (-Y) side of the processing chamber 412, a seal member 422 is provided to maintain the gas-tight state of the processing space SP. The seal member 422 is made of, for example, rubber. Further, the lid member 413 is fixed with respect to the processing chamber 412 by a locking mechanism, which is not shown. In this way, in the present embodiment, the lid member 413 is switched between a state of occluding the opening 421 to seal the processing space SP (solid line) and a state of being largely separated from the opening 421 so that the substrate S can be accessed (broken line).

[0052] In a state in which the airtightness of the processing space SP is ensured, processing of the substrate S is performed in the processing space SP. In the present embodiment, the fluid supply unit 45 is provided with a fluid supply section 457 that sends out a processing fluid, such as carbon dioxide, which is a chemical substance that can be used for supercritical processing, as the processing fluid. Also, the processing fluid is brought to a supercritical state by being pressurized in the processing chamber 412. The processing fluid is supplied to the processing unit 41 in a gaseous or liquid state. Carbon dioxide becomes a supercritical state at a relatively low temperature and low pressure, and, in addition, has the property of dissolving organic solvents that are often used in substrate processing well, and is thus a chemical substance that is suitable for supercritical drying processing. The critical point at which carbon dioxide becomes a supercritical state is a gas pressure (critical pressure) of 7.38 MPa and a temperature (critical temperature) of 31.1°C.

[0053] When the processing space SP is filled with the processing fluid, and the processing space SP is brought to an appropriate temperature and pressure, the processing space SP is filled with the processing fluid in a supercritical state. Thus, the substrate S is processed in the processing chamber 412 with the processing fluid in a supercritical state. The fluid supply section 457 and the fluid recovery section 455 are controlled by the supercritical processing control section 97.

[0054] The processing space SP has a shape and volume that can receive the support tray 415 and the substrate S supported on the support tray 415. That is, the processing space SP has a substantially rectangular cross-sectional shape that is wider than the width of the support tray 415 in the horizontal direction, and greater than the total height of the support tray 415 and the substrate S in the vertical direction, and a depth that can receive the support tray 415. Thus, the processing space SP has a shape and volume that receives only the support tray 415 and the substrate S. However, the gap between the support tray 415 and the substrate S and the inner wall surface of the processing space SP is small. Therefore, the amount of processing fluid required to fill the processing space SP is relatively small.

[0055] The fluid supply section 457 supplies the processing fluid to the processing space SP further on the (+Y) side than the (+Y) side end portion of the substrate S. On the other hand, the fluid recovery section 455 discharges the processing fluid that flows through the space above the substrate S and the space below the support tray 415 in the processing space SP further on the (-Y) side than the (-Y) side end portion of the substrate S. Thus, in the processing space SP, a laminar flow of the processing fluid is formed from the (+Y) side toward the (-Y) side in each of the space above the substrate S and the space below the support tray 415.

[0056] The supercritical processing control unit 97 of the control device 9, based on the detection results of a detection unit (not shown), measures the pressure and temperature within a specific processing space SP, and controls the fluid supply unit 457 and the fluid recovery unit 455 accordingly. This appropriately manages the supply of processing fluid to the processing space SP and the discharge of processing fluid from the processing space SP. The pressure and temperature within the processing space SP are adjusted according to a predetermined processing formula.

[0057] The transfer unit 43 is responsible for transferring the substrate S between the substrate transfer device 3 and the support tray 415. For this purpose, the transfer unit 43 includes a body 431, a lifting member 433, a base member 435, and multiple lifting pins 437. The lifting member 433 is a columnar member extending in the Z direction, supported by a support mechanism (not shown), which allows it to move freely in the Z direction relative to the body 431. The base member 435, having a generally horizontal upper surface, is mounted on the upper part of the lifting member 433. Multiple lifting pins 437 are erected facing upwards from the upper surface of the base member 435. Each lifting pin 437 abuts against the lower surface of the substrate S at its upper end, supporting the substrate S in a horizontal position from below. To stably support the substrate S in a horizontal position, it is desirable to provide three or more lifting pins 437 with equal upper end heights.

[0058] The lifting component 433 can be moved up and down via a lifting mechanism 451 provided in the supply unit 45. Specifically, the lifting mechanism 451 may be a linear motor, a direct-acting guide, a ball screw mechanism, a solenoid, or a cylinder, etc. This direct-acting mechanism causes the lifting component 433 to move in the Z direction. The lifting mechanism 451 operates according to control commands from the control device 9.

[0059] The base component 435 moves up and down due to the lifting mechanism 433, and multiple lifting pins 437 move up and down together with it. This achieves the transfer of the substrate S between the transfer unit 43 and the support tray 415. More specifically, as... Figure 4 As shown by the dashed line, the substrate S is transferred when the support tray 415 is pulled out of the cavity. For this purpose, the support tray 415 is provided with a through hole 419 for inserting the lifting pin 437. When the base component 435 rises, the upper end of the lifting pin 437 reaches above the upper surface of the support tray 415 through the through hole 419. In this state, the substrate S, which has been transported by the transfer robot 30, is transferred from the hand 31 of the transfer robot 30 to the lifting pin 437. As the lifting pin 437 descends, the substrate S is transferred from the lifting pin 437 to the support tray 415. The substrate S can be removed in the reverse order.

[0060] Next, the supply path of the processing fluid to the processing chamber 412 and the discharge path of the processing fluid from the processing chamber 412 will be described in more detail. Above, the supply of processing fluid from the fluid supply unit 457 to the processing chamber 412 and the recovery of processing fluid from the processing chamber 412 to the fluid recovery unit 455 were briefly described. In the actual device, the fluid supply unit 457 and the fluid recovery unit 455 have the following configuration.

[0061] Figure 5 It is a diagram showing the details of the supply and discharge paths for the processed fluid. Additionally, Figure 5 In the diagram, for ease of illustration, the orientation of the processing chamber 412 is shown in the figure. Figure 4 On the contrary, that is to say, Figure 4 In the middle, the processing fluid is introduced into the processing chamber 412 from the right side of the paper and discharged to the left side of the paper. On the other hand, Figure 5 Conversely, the flow becomes one where the processing fluid is introduced into the processing chamber 412 from the left side of the paper and discharged to the right side of the paper. That is to say, Figure 5 In the processing chamber 412, a diagram showing the relationship with... Figure 4 The processing chamber 412 is on the opposite side.

[0062] First, the detailed structure of the fluid supply unit 457 will be described. The fluid supply unit 457 mainly consists of a fluid supply source 700, a purification unit 710, a supply unit 720, and piping groups 730 and 740 connecting these. These operate according to control commands from the supercritical processing control unit 97.

[0063] The fluid supply source 700 outputs the substance used as a processing fluid in the supercritical process (carbon dioxide in this embodiment) as needed. The fluid supply source 700 may also be provided as part of the substrate processing system 1 and may be constituted by a container for storing the substance, such as a high-pressure gas cylinder. Alternatively, it may be an external supply source separately provided with the substrate processing system 1.

[0064] At the fluid supply source 700, a portion of the piping group 730, namely piping 731, is connected. The processed fluid delivered from the fluid supply source 700... Figure 5 The fluid flows through piping 731 from center to right. In piping 731, along the flow direction of the processed fluid, valves V70 and V71, purifier 711, filter 712, condenser 713, and valve V72 are sequentially arranged. Valve V70 is, for example, a pressure regulating valve that functions to adjust the pressure of the processed fluid flowing through piping 731. The other valves, V71 and V72, are on / off valves that switch the flow of fluid.

[0065] The valve V70 causes the treatment fluid at a pressure specified in accordance with a control command from the supercritical treatment control section 97 to flow in the pipe 731. The purifier 711 and the filter 712 remove impurities contained in the treatment fluid, and increase the purity. The condenser 713 condenses the treatment fluid sent out as a gas from the fluid supply source 700. When the valves V71 and V72 are opened, the treatment fluid is output from the pipe 731.

[0066] The pipe 731 merges with the pipe 735 connected to the tank 717 described later on the output side of the valve V72. In the pipe 732 after the merging, the condenser 714, the pressurizing pump 715, and the filter 716 are provided. The condenser 714 is provided in order to more surely maintain the treatment fluid in a liquid phase state. The pressurizing pump 715 pressurizes and sends out the treatment fluid in a liquid state. The filter 716 removes impurities from the treatment fluid.

[0067] The pipe 732 branches into two pipes 733 and 734 on the output side of the filter 716. The pipe 733 is connected to the upper portion of the tank 717, and an on-off valve, that is, the valve V74 is interposed in the middle of the way. Further, the on-off valve, that is, the valve V75 is interposed in the pipe 734.

[0068] The tank 717 is a high-pressure container having a function of storing the treatment fluid pressurized in a liquid state. A liquid level sensor 718 is provided in the tank 717, and the height of the liquid surface is managed. Therefore, the inside space of the tank 717 does not become a liquid-tight state, and the treatment fluid gasified is stored in a state pressurized to the same degree as the liquid in the space above the liquid surface. Further, a heater 719 is installed in the tank 717, and the heater 719 can heat the treatment fluid in the tank in accordance with a control command from the supercritical treatment control section 97.

[0069] The pipe 735 is connected to the lower portion of the tank 717, and merges with the pipe 731, and is connected to the pipe 732. When the on-off valve, that is, the valve V73 interposed in the pipe 735 is opened, the liquid of the treatment fluid in the tank 717 flows into the pipe 732 via the pipe 735. If the valve V74 on the pipe 733 is further opened, a reflux flow path from the tank 717 through the pipes 735, 732, and 733 to the tank 717 is formed. If the treatment fluid is pressurized by the pressurizing pump 715 while circulating the treatment fluid in the reflux path, the pressure of the treatment fluid can be increased in stages. Finally, the treatment fluid is stored in the tank 717 in a state increased to a pressure specified in accordance with a control command from the supercritical treatment control section 97.

[0070] The output pipe 736 is connected to the upper portion of the tank 717, and merges with the pipe 734 via an on-off valve, i.e., the valve V76. The gas-like process fluid filled in the upper portion of the internal space of the tank 717 is output from the pipe 736. The gas-like process fluid when the valve V76 is open and the liquid-like process fluid when the valve V75 is open selectively flow into the pipe 741 after merging with the pipe 734 and the pipe 736.

[0071] Thus, the refining unit 710 of the fluid supply section 457 has a function of selectively outputting the phase, specifically, the gas phase and the liquid phase of the process fluid required for the subsequent process after removing the impurities from the process fluid supplied from the fluid supply source 700.

[0072] The pipe 741 becomes a part of the pipe group 740 constituting the introduction flow path of the process fluid introduced from the refining unit 710 to the processing chamber 412. The pipe 741 is branched into two pipes 743 and 744 on the downstream side of an on-off valve, i.e., the valve V77, and the filters 721 and 722 are respectively provided in the respective pipes. These pipes 743 and 744 temporarily merge into the pipe 745, and are further branched into two pipes 747 and 748.

[0073] In the pipe 747, a flow meter 723, a heater 725, an on-off valve, i.e., the valve V78, and a filter 727 are sequentially interposed in the flow direction of the process fluid (rightward in the figure), and the pipe 747 is finally connected to the processing chamber 412. More specifically, the pipe 747 is connected to the internal space SP above the support tray 415 (see FIG. 2) supporting the substrate S, on the downstream side of the valve V77. On the other hand, in the pipe 748, a flow meter 724, a heater 726, an on-off valve, i.e., the valve V79, and a filter 728 are sequentially interposed in the flow direction of the process fluid. Further, the pipe 748 is connected to the internal space SP below the support tray 415 (see FIG. 2) supporting the substrate S, on the downstream side of the valve V79. Thus, the internal space SP is supplied with the process fluid to each of the spaces above and below the substrate S placed on the support tray 415. Figure 4 Figure 4

[0074] The flow meters 723 and 724 measure the flow rate of the process fluid at the respective positions, and transmit the results to the supercritical process control section 97. The heaters 725 and 726 heat the process fluid to a predetermined temperature according to the control command from the supercritical process control section 97. The filters 727 and 728 finally remove the impurities from the process fluid introduced into the processing chamber 412.

[0075] Thus, the fluid supply section 457 can supply the process fluid, which is purified and further adjusted in temperature and pressure to predetermined target values, to the processing chamber 412. The order of the supply of the process fluid from the fluid supply section 457 to the processing chamber 412 will be described in detail later.​​

[0076] The processing fluid supplied to the processing chamber 412 is sent from the tank 717, and the processing fluid pressurized by the pressurizing pump 715 is stored in the tank 717. Therefore, the pressure of the processing fluid sent from the fluid supply source 700 can also be lower than the pressure required for processing. In addition, in the case where the fluid supply source 700 is capable of stably sending the processing fluid at a pressure suitable for processing, as shown by the alternate long and short dash line, the processing fluid in the gaseous phase can also be supplied directly from the fluid supply source 700 via the pipe 737 without being taken from the tank 717. Furthermore, the processing fluid after pressure adjustment can also be supplied from the output side of the valve V70. Figure 5

[0077] As described above, in the fluid supply section 457 of the present embodiment, the refining unit 710 has a function of purifying and liquefying the processing fluid output as a gas from the fluid supply source 700 and storing it. Furthermore, the processing fluid output as a liquid from the refining unit 710 is heated in the supply unit 720 to become in a supercritical state, and is introduced into the processing chamber 412.

[0078] On the flow path of the processing fluid, a plurality of filters are arranged. Specifically, the filter 712 is interposed in the pipe 731 through which the processing fluid flows as a gas. The processing fluid at this time is always a gas, and after the pressure thereof is adjusted by the pressure regulating valve, that is, the valve V70, a filter unit capable of applying a gas at a pressure suitable for processing to the filter 712 can be used. For example, a filter unit of a configuration in which a filter element is housed in a resin-made housing can be used.

[0079] On the other hand, the filters on the upstream side of the filters arranged in the supply unit 720, that is, the filters 721, 722 are interposed in the pipe 741 through which the processing fluid flows as a liquid at a high pressure. The processing fluid flowing in the pipe 741 is always a liquid, and the pressure thereof is also stable. Therefore, a filter unit suitable for processing of such a liquid, for example, a filter unit of a configuration in which a filter element is housed in a metal-made housing can be used. The filter units for the two filters 721, 722 are configured to be the same as each other here.

[0080] The filters 721, 722 are connected in parallel on the flow path. That is, filter units of the same configuration are arranged in parallel on the flow path of the liquid. The main reasons for this are as follows. The first reason is to ensure a sufficiently large flow rate of the processing fluid in the section. The second reason is to suppress a decrease in the temperature of the filter unit.

[0081] ​The first reason will be explained in more detail. The flow path of the process fluid branches into two on the downstream side of the filters 721, 722, and the process fluid is supplied to the space above the substrate S in the process space SP and the space below the support tray 415, respectively. Since the process fluid supplied to these two is supplied through the pipe 741, a large capacity is required for the filters that receive it.

[0082] In this sense, a filter unit with a larger capacity alone can be used. However, filter units with excellent particle removal performance are mostly small, and merely using a filter unit with a large capacity cannot achieve the required filtration performance. Therefore, by connecting filter units with excellent performance in parallel, both high filtration performance and a large capacity can be achieved.

[0083] Three or more filter units can also be connected in parallel. However, an increase in the number of parts such as pipes or joints that connect them is also considered to increase the cause of contamination. Therefore, the number of filter units to be installed is preferably determined in consideration of the balance between performance and capacity.

[0084] Next, the second reason will be explained in more detail. The filter at the position is a filter for the process liquid. The fluid in the liquid phase has a higher viscosity than other states, and therefore the pressure loss in the filter is also larger. Therefore, the temperature decreases due to the sharp pressure drop of the process fluid passing through the filter, and the filter unit is cooled. In the experiments of the present inventor, it was confirmed that condensation actually occurred in the housing. In particular, in a filter unit having a metal housing, corrosion or rust due to condensation is a concern.

[0085] A more serious problem is that the process fluid itself is cooled and partially solidified in the filter unit, causing clogging of the filter. As a result, the flow rate of the process fluid decreases, and the pressure loss further increases, so that the clogging once generated is not easily eliminated. In addition, fluctuations in the flow rate of the process fluid have a large impact on the processing in the processing chamber 412.

[0086] By connecting filter units in parallel, the flow of the process fluid is distributed, and the pressure loss in each filter unit is reduced, and the temperature decrease also becomes slow. As a result, the risk of clogging due to condensation on the housing or solidification of the process fluid in the filter unit can be greatly reduced.

[0087] The filters 727, 728 disposed in the flow path immediately before the processing chamber 412 finally determine the cleanliness of the processing fluid introduced into the processing space SP. Therefore, a higher particle removal performance is required. Therefore, a filter unit using a metal case that is less likely to become a new source of contamination is suitably used. Although a problem of temperature reduction can occur in this case as well, unlike the filters 721, 722, it is not a large problem. The reason is as follows. First, since the fluid to be processed is a supercritical fluid having a low viscosity, the pressure loss is small. Further, since the processing fluid is heated by the heaters 725, 726, there is less concern that the temperature will be reduced to a low temperature at which dew condensation or solidification of the processing fluid occurs.

[0088] Further, the processing fluid is preliminarily divided into two flow paths. Therefore, it is not necessary to connect filter units in parallel in each flow path. Further, in the filters 727, 728, performance is more emphasized, and a small filter unit having a high performance can also be used in parallel.

[0089] It is assumed that a filter unit for processing a supercritical fluid is not easily obtained in general. However, the supercritical fluid can also be regarded as a liquid having a very low viscosity, and a filter designed for such a liquid can be used as it is. For example, the filters 727, 728 can be constituted by filter units having the same configuration as the filters 721, 722. In this case, a cost advantage resulting from the common use of the filter body and replacement parts is obtained.

[0090] The processing fluid flows through the filter 716 disposed on the downstream side of the pressurizing pump 715 as a liquid. The processing fluid has a large pressure change due to a relatively large flow rate. Therefore, it is desirable to use a filter unit suitable for such use. For example, a filter unit in which a filter element is housed in a metal case can be used. In addition, a plurality of filter units can also be connected in parallel here. However, a higher particle removal performance is not necessarily required for the filter at this position. Therefore, a filter unit having a large capacity but a slightly poor performance can also be used alone.

[0091] In this way, several filters are disposed in the flow path of the processing fluid, and each filter is appropriately selected in accordance with the state of the fluid to be processed or the required performance.

[0092] Next, the detailed configuration of the fluid recovery section 455 will be described. The fluid recovery section 455 has, as main components, a high-pressure exhaust tank 505, a low-pressure exhaust tank 508, and a pipe group 530 connecting these exhaust tanks. These operate in accordance with a control command from the supercritical processing control section 97.

[0093] In the upper portion of the processing chamber 412, a pipe 531 which is a part of the pipe group 530 is connected. On the other hand, a pipe 532 is connected to the lower portion of the processing chamber 412. These pipes 531, 532 respectively discharge the processing fluid which flows in the inside space SP above and below the support tray 415 from the processing chamber 412 to the outside. In the pipe 531, a pressure gauge 503 is provided.

[0094] In the pipe 531, a flow meter 501, an on-off valve, that is, a valve V51 are sequentially interposed in the flow direction of the processing fluid. On the other hand, in the pipe 532, a flow meter 502, an on-off valve, that is, a valve V52 are sequentially interposed in the flow direction of the processing fluid. In the output side of the valves V51, V52, the pipes 531, 532 are merged. In the merged pipe 533, a pressure regulating valve, that is, a valve V53, an on-off valve, that is, a valve V54 are interposed.

[0095] The pipe 533 is connected to the high-pressure exhaust tank 505, and the processing fluid discharged from the processing chamber 412 is stored in the high-pressure exhaust tank 505 via the pipe 533. In the high-pressure exhaust tank 505, a heater 506 is provided, and the temperature of the processing fluid stored in the inside is appropriately maintained.

[0096] In the upper portion of the high-pressure exhaust tank 505, a pipe 544 is connected, and in the pipe 544, an on-off valve, that is, a valve V55, a pressure regulating valve, that is, a valve V56, and a heater 507 are interposed, and the pipe 544 is finally connected to a low-pressure exhaust tank 508. Therefore, the processing fluid which is a gas whose pressure and temperature are appropriately adjusted flows into the low-pressure exhaust tank 508. The processing fluid in the low-pressure exhaust tank 508 is finally recovered by an external recovery device which is not shown via a pipe 545. In the pipe 545, a heater 509 for adjusting the temperature of the gas discharged to the outside, and a pressure gauge 510 for detecting the pressure of the gas are provided.

[0097] Further, in the lower portion of the high-pressure exhaust tank 505, a pipe 546 is connected, and on the other hand, in the lower portion of the low-pressure exhaust tank 508, a pipe 547 is connected. These pipes are merged to become a pipe 548, and in the pipe 548, an on-off valve, that is, a valve V57 is connected. When the valve V57 is opened, the processing fluid which is a liquid stored in the high-pressure exhaust tank 505 and the low-pressure exhaust tank 508 is discharged to the external recovery device.

[0098] Reference Figure 6 and Figure 7 The operation of the supercritical processing device 4 configured as described above will be described. The supercritical processing device 4 performs a processing of bringing the substrate S after wet processing to a dry state using a processing fluid in a supercritical state, that is, a supercritical dry processing. The processing is realized by controlling the device by the CPU 91 of the control device 9 which executes a control program prepared in advance.

[0099] Figure 6 is a flowchart showing the processing performed by the supercritical processing apparatus. Furthermore, Figure 7 is a graph showing the changes in the pressures in the processing chamber and the tank during the processing. The fluid supply section 457 supplies the processing fluid of gas and liquid from the tank 717 storing the processing fluid to the processing chamber 412. Therefore, the pressure in the processing space SP of the processing chamber 412 (hereinafter, referred to as "chamber internal pressure") and the pressure of the internal space of the tank 717 (hereinafter, referred to as "tank internal pressure") change as the processing progresses.

[0100] First, the substrate carrying device 3 cooperates with the supercritical processing apparatus 4 to carry the substrate S into the processing chamber 412 (step S101). Specifically, the carrying robot 30 of the substrate carrying device 3 holds the substrate S on which the liquid film formation processing in the wet processing apparatus 2 has been completed, and places the substrate S on the support tray 415 in a state pulled out from the processing chamber 412. More specifically, first, the substrate S is handed over from the hand 31 of the carrying robot 30 to the lift pins 437 of the supercritical processing apparatus 4, and then the substrate S is handed over from the lift pins 437 to the support tray 415.

[0101] The support tray 415 on which the substrate S is placed is housed in the processing chamber 412. The processing space SP inside the processing chamber 412 is sealed by closing the opening 421 of the processing chamber 412 with the lid member 413. In this way, the carrying-in of the substrate S is completed. Since the processing chamber 412 is opened to the atmosphere in order to carry in the substrate S, as shown in the upper part of the figure, the internal pressure of the processing chamber 412 is atmospheric pressure Pa in the initial state. Figure 7

[0102] In this way, during the handover of the substrate S, a prescribed standby operation is performed in the fluid supply section 457 (step S102). The details of the standby operation are described later, and the standby operation is an operation in the fluid supply section 457 to prepare the required amount of processing fluid suitable for the temperature and pressure used in the subsequent processing. As described later, in the embodiment, carbon dioxide in a gaseous state at a temperature of 20°C and a pressure of 6 MPa, and carbon dioxide supercriticalized by heating from a temperature of 20°C and a pressure of 11 MPa are used for the processing.

[0103] After the substrate S is carried in, the processing fluid in a gaseous phase is introduced from the fluid supply section 457 (step S103; time T1), and thus the chamber internal pressure gradually rises. When the chamber internal pressure rises to a predetermined first pressure PI (step S104; time T2), the processing fluid in a supercritical state is supplied from the fluid supply section 457 to the processing chamber 412 to replace the gas (step S105; time T3).

[0104] ​Thus, the processing space SP of the processing chamber 412 is filled with a supercritical processing fluid, and the internal pressure of the chamber is maintained at a first pressure P1 and a certain second pressure P2 (at times T4 to T5) that is greater than the critical pressure of the processing fluid. During this period, the liquid remaining attached to the substrate S is replaced by the supercritical processing fluid, dissolved into the processing fluid, and removed from the front side of the substrate S.

[0105] When the pressure inside the chamber is maintained at approximately pressure P2 for a predetermined time (step S106), the processing fluid begins to be discharged from the processing chamber 412 (step S107; time T5), thereby depressurizing the processing space SP. After the pressure inside the chamber decreases to near atmospheric pressure Pa at time T7, the substrate S is removed by the transfer robot 30 (step S108), and the processing of one substrate S is completed. Then, if there are substrates to be processed, return to step S101 (step S109) and repeat the process.

[0106] like Figure 7 As shown in the next section, the pressure inside the tank gradually decreases as the processing fluid stored in the tank 717 is consumed. To restore it, pressurized processing fluid is replenished to the tank 717; for this purpose, a standby operation (step S111) is performed. The standby operation can be performed after the moment T6 when the supply of processing fluid from the tank 717 to the processing chamber 412 stops. Therefore, as... Figure 7 As shown, during the decompression process within the processing chamber 412, a standby operation can be initiated.

[0107] When performing supercritical drying on substrate S, it is desirable to pre-increase the tank pressure to the same level as or slightly higher than the first pressure P1 during standby operation, in a manner that allows the chamber pressure to be increased to the first pressure P1 in step S103 of the process.

[0108] Specifically, the processing fluid output from the fluid supply source 700 is pressurized by the booster pump 715 and flows into the storage tank 717. This raises the pressure inside the tank to a target value. For this purpose, valves V71, V72, and V74 are opened, while valves V73, V75, and V76 are closed.

[0109] Therefore, the processed fluid, output from the fluid supply source 700 and whose pressure is adjusted by valve V70, is stored in the storage tank 717 as a liquid pressurized to a specified pressure by the booster pump 715. The liquid level in the tank is monitored by the level sensor 718. The processed fluid continues to be supplied until a predetermined amount of liquid at a predetermined pressure has been accumulated. In addition, the temperature of the processed fluid in the tank is adjusted by the heater 719.

[0110] Thus, during the standby period when no processing fluid is supplied from storage tank 717 to processing chamber 412 ( Figure 7the time Tl and after the time T6), the process for maintaining the liquid amount, pressure, and temperature in the tank at predetermined values is executed. The target value of the pressure is the first pressure PI or a pressure slightly higher than the first pressure PI, and in this embodiment, 6 MPa. Further, the target temperature is 20°C in this embodiment. Further, the target value of the liquid amount is set to an amount that can sufficiently supply the processing chamber 412 with the processing fluid in the supercritical drying process.

[0111] As described above, in the first embodiment of the substrate processing apparatus of the present application, the filters are arranged at a plurality of positions on the flow path of the processing fluid, and purification of the processing fluid is sought. The processing fluid is liquefied as a gas output, and finally becomes a supercritical state by heating, and is introduced into the processing chamber. The filters are arranged optimally according to the state of the processing fluid at each position. In other words, each filter is arranged at a position where the processing fluid flowing in the flow path of the processing fluid is a gas, a position where the processing fluid is a liquid, and a position where the processing fluid is in a supercritical state, respectively.

[0112] Thus, the filters can be arranged optimally according to the state or purpose of the processing fluid. As a result, the purified processing fluid can be used effectively, and the processing of the substrate can be performed well. Further, among the substances contained in the processing fluid that become a source of contamination of the substrate, a substance that is easily removed in a state where the processing fluid is a gas, a substance that is easily removed in a state where the processing fluid is a liquid, and a substance that is easily removed in a state where the processing fluid is supercritical can be mixed. By arranging the filters at the flow path of the processing fluid in each phase, respectively, these contaminant substances can be removed effectively.

[0113] As described above, in the embodiment, the supercritical processing apparatus 4 corresponds to the "substrate processing apparatus" of the present application. Further, the processing chamber 412 having the processing space SP as an "internal space" functions as the "processing chamber" of the present application. Further, the fluid supply section 457 has a function as the "supply section" of the present application.

[0114] Further, in the embodiment, the pipe groups 730, 740, and the valves of the entire pipe arranged on the pipe function as the "flow path forming section" of the present application. Further, the heaters 725, 726 function as the "heating section" of the present application. Further, the filters 721, 722 correspond to the "filter units" of the present application, respectively. Together with them, they integrally constitute the "first filter section" of the present application. On the other hand, the filters 727, 728 individually correspond to the "second filter section" of the present application, respectively. Further, the pipes 747, 748 in which these filters are arranged correspond to the "branch paths" of the present application, respectively.

[0115] Further, in the embodiment, the fluid supply source 700 functions as the "gas supply source" of the present application, and the refining unit 710 functions as the "liquefying mechanism" of the present application. Also, the filter 712 functions as the "third filter section" of the present application.

[0116] <2nd Embodiment>

[0117] Figure 8 is a view showing a 2nd embodiment of the substrate processing apparatus. In addition, the substrate processing apparatus of the 2nd embodiment and each of the embodiments described later is a substrate processing apparatus in which a constituent part of the supply unit 720 in the 1st embodiment is changed. The other constituents are the same as those of the 1st embodiment. Therefore, in order to indicate the point of change from the supply unit 720, the description of the constituents whose configuration and function are the same as those of the 1st embodiment is omitted, or the same reference numerals are marked and the detailed description is omitted.

[0118] As shown in Figure 8 , in the supply unit 720A of the 2nd embodiment, liquid filters 721A, 722A are provided in the pipes branched from the pipe 741. That is, the pipes 743, 744 provided in the 1st embodiment are removed, and two pipes 747A, 748A are directly branched from the pipe 741. Also, in one pipe 747A, the liquid filter 721A, the flow meter 723, the heater 725, the valve V78, and the supercritical fluid filter 727 are arranged.

[0119] Here, as for the filter 721A, as shown by the solid line in the drawing, it can be provided on the upstream side of the flow meter 723, and in addition, as shown by the broken line, it can be provided on the downstream side of the flow meter 723. The drawing shows that the filter 721A is provided at one of the positions, but does not show that it is provided at both.

[0120] In addition, in the other pipe 748A, the liquid filter 722A, the flow meter 724, the heater 726, the valve V79, and the supercritical fluid filter 728 are also arranged. Here, as for the position of the filter 722A, either of the front and rear of the flow meter 723 can be adopted.

[0121] According to this configuration, by omitting the pipes 743, 744, it is possible to reduce the structures that can become a source of contamination. In this case, the flow rate of the processing fluid in each filter 721A, 722A is the same degree as that of the filters 721, 722 connected in parallel. Therefore, it is possible to separately use the filter units of the same degree.

[0122] <3rd Embodiment>

[0123] Figure 9is a view showing a third embodiment of the substrate processing apparatus. The supply unit 720B of the present embodiment differs from the first embodiment in that a filter for supercritical fluid is connected in series. That is, another filter 727B is arranged on the upstream side or the downstream side of the filter 727. Further, another filter 728B is also arranged on the upstream side or the downstream side of the filter 728. The two filters 727, 727B connected in series can be the same configuration, and further, can be different configurations in order to distinguish the use according to the purpose. The same applies to the other two filters 728, 728B.

[0124] The connection in series of such filters can improve the particle removal performance, and on the other hand, increase the pressure loss on the flow path. In the flow path of the supercritical fluid having extremely low viscosity, such a configuration can also be allowed.

[0125] <Fourth Embodiment>

[0126] Figure 10 is a view showing a fourth embodiment of the substrate processing apparatus. The supply unit 720C of the present embodiment differs from the first embodiment in that filters for supercritical fluid are connected in parallel. That is, the filter 727C is connected in parallel to the filter 727 arranged in the flow path of the supercritical fluid, and the filter 728C is connected in parallel to the filter 728. Regarding such a configuration, as mentioned also in the explanation of the first embodiment. Thus, by adopting the connection in parallel, even a small capacity can apply a filter unit having higher performance. Thereby, the cleanliness of the processing fluid introduced to the processing chamber 412 can be further improved.

[0127] <Other Modification Examples>

[0128] Further, the present application is not limited to the embodiments described above, and various modifications can be made thereto without departing from the spirit of the present application. For example, in the fluid supply part 457 of the embodiments described above, a configuration such as a flow meter or the like is generally arranged in the flow path of the processing fluid, but is not directly related to the present application. Even if these are omitted, the present application can be established.

[0129] Further, for example, in the embodiments described above, the introduction of the processing fluid to the processing chamber 412 and the discharge of the processing fluid from the processing chamber 412 are performed individually on each of the upper side and the lower side of the support tray 415. However, this is not an essential requirement of the technical idea of the present application.

[0130] Further, in the embodiments described above, the fluid supply source 700 outputs the processing fluid as a gas. Therefore, the gas filter 712 is interposed in the pipe 731 which becomes the flow path of the gas. If the fluid supply source outputs the processing fluid as a liquid, the filter can be changed to a filter for liquid or omitted.

[0131] Further, as shown by a broken line in the figure, in a case where a pipe 737 is provided which is directly connected from the fluid supply source 700 to the valve V76, it is desirable that a filter for gas be interposed in the pipe 737. Figure 5

[0132] Further, the various chemicals and numerical values used in the processing of the embodiment are shown as examples of chemicals and numerical values, and various chemicals and numerical values can be used in place of them if they are consistent with the technical idea of the present application.

[0133] As described above with reference to the specific embodiments, in the substrate processing apparatus of the present application, for example, the flow path can be branched into a plurality of branch paths, and the heating section and the second filter section can be provided individually for each of the branch paths. According to this configuration, the processing fluid can be supplied to the processing chamber from a plurality of sites. By providing the heating section and the second filter section in the flow paths, respectively, the temperature and the cleanliness of the supplied processing fluid can be appropriately maintained.

[0134] In this case, the flow path can be configured, for example, in such a manner that it is branched on the output side of the first filter section, and further, the first filter section can be provided individually for each of the branch paths. According to either configuration, the processing fluid that has passed through the first filter section as a liquid can be supplied to the processing chamber as a supercritical fluid.

[0135] Further, for example, the first filter section can be configured by a plurality of filter units having the same configuration and connected in parallel with each other. The performance and the magnitude of the pressure loss of the filter are in a trade-off relationship, and in particular, in the first filter section that processes the liquid, the pressure loss often becomes large. Further, there are cases where it is not easy to prepare a filter having a high performance and a large capacity. Therefore, by connecting a plurality of filter units in parallel with each other at a necessary performance, capacity expansion can be sought without losing the performance.

[0136] Further, when the pressure loss is large, the pressure of the processing fluid decreases, and the temperature of the processing fluid that is caused thereby can become a problem. In particular, in a case where the filter unit has a configuration in which the filter element is housed in a metal-made housing, dew condensation that is caused by the decrease in the temperature of the processing fluid becomes a cause of rust or corrosion of the housing. By connecting the filter units in parallel with each other, the processing fluid is dispersed, and thereby, this decrease in the temperature can be alleviated.

[0137] ​Further, for example, the 2nd filter section can also have a filter unit of the same configuration as the filter unit of the 1st filter section. The process fluid handled by the 2nd filter section is in a supercritical state. However, a filter unit optimized for the same cannot be said to be sufficiently supplied in the market. If the fluid in a supercritical state is regarded as a liquid with extremely low viscosity, then a filter unit capable of handling such a liquid can be applied. Thus, for example, a filter unit of the same configuration as the filter unit handling the liquid used by the 1st filter section can be used. Thereby, cost advantages brought about by commonality of parts are obtained.

[0138] Further, in the present application, for example, the supply section can be configured to have: a gas supply source that outputs a process fluid as a gas; a liquefaction mechanism that pressurizes or cools the process fluid output from the gas supply source to liquefy the same; and the liquefaction mechanism that outputs the process fluid as a liquid to the flow path. According to this configuration, as the gas supply source, for example, a gas cylinder that can be supplied in the market can be used for the process. Thereby, the cost of the process of the substrate can be reduced.

[0139] In this case, it is desirable that the gas supply source and the liquefaction mechanism be connected via a 3rd filter section that filters the process fluid of the gas. Thereby, contaminant substances such as particles contained in the gas can be removed before liquefaction. Further, since the level of cleanliness required for the gas supply source is reduced, the cost of supply thereof can be suppressed.

[0140] The application has been described above with reference to specific embodiments, but the description is not intended to be construed in a limiting sense. Rather, various changes and modifications can be apparent to those skilled in the art, once given the benefit of the description of the application. Therefore, the scope of the application is not intended to be limited to the particular embodiments described herein, but includes all changes and modifications that come within the scope of the application.

[0141] [Industrial Applicability]

[0142] The present application can be applied to the entire technology of processing a substrate with a process fluid in a supercritical state in a processing chamber.

[0143] [Explanation of Symbols]

[0144] 4 supercritical processing apparatus (substrate processing apparatus)

[0145] 412 processing chamber

[0146] 457 fluid supply section (supply section)

[0147] 700 fluid supply source (gas supply source)

[0148] 710 refining unit (liquefaction mechanism)

[0149] 712 filter (3rd filter section)

[0150] 715 pressurizing pump (pressurizing section)

[0151] 721, 722 filter (filter unit, 1st filter section)

[0152] 725, 726 heater (heating section)

[0153] 727, 728 filter (2nd filter section)

[0154] 730, 740 piping group (flow path forming section)

[0155] 747, 748 pipe (branch path)

[0156] S substrate

[0157] SP processing space (internal space)

Claims

1. A substrate processing apparatus, comprising a substrate processing apparatus for processing a substrate using a supercritical processing fluid, comprising: The processing chamber has an internal space capable of accommodating the substrate; The supply unit is capable of supplying the processing fluid as a liquid. The heating unit heats the liquid being processed from the supply unit to a temperature above the critical temperature of the processed fluid, thereby transferring it to a supercritical state. A flow path forming section forms a flow path for the processing fluid from the supply section through the heating section to the processing chamber; The first filtration unit is inserted into the flow path between the supply unit and the heating unit to filter the liquid processing fluid; and The second filtration section is interposed in the flow path between the heating section and the processing chamber to filter the supercritical processing fluid.

2. The substrate processing apparatus according to claim 1, wherein the flow path is branched into a plurality of branch paths, each of the branch paths being connected to the processing chamber, and the heating unit and the second filtering unit are individually provided for each of the branch paths.

3. The substrate processing apparatus according to claim 2, wherein the flow path branches off on the output side of the first filter section.

4. The substrate processing apparatus according to claim 2, wherein the first filter section is individually provided in each of the branch paths.

5. The substrate processing apparatus according to claim 1, wherein the first filter section has a plurality of filter units with the same structure and connected in parallel with each other.

6. The substrate processing apparatus according to claim 5, wherein the filter unit has a configuration in which a filter element is housed within a metal housing.

7. The substrate processing apparatus according to claim 5, wherein the second filter section has a filter unit with the same structure as the filter unit.

8. The substrate processing apparatus according to any one of claims 1 to 7, wherein the supply unit has a gas supply source for outputting the processing fluid as gas, and a liquefaction mechanism for pressurizing or cooling the processing fluid output from the gas supply source to liquefy it. The liquefaction mechanism outputs the liquid processing fluid into the flow path.

9. The substrate processing apparatus of claim 8, wherein the gas supply source is connected to the liquefaction mechanism via a third filter section of the processing fluid through which the gas is filtered.

Images