Substrate processing method and substrate processing system

Abstract

The present invention provides a substrate processing method that reduces the consumption of processing fluid and environmental burden while increasing throughput. The substrate processing method and substrate processing system of the present invention perform a preliminary organic solvent supply process between a chemical liquid process and a rinse process. Then, after the rinse process, a displacement process using an organic solvent and a liquid stacking process (liquid film formation process) are performed, forming a liquid film. At this time, sometimes the rinse liquid remains within the pattern, but the position of the remaining rinse liquid is not the inner bottom surface of the pattern, but a position sandwiched by liquid layers containing two kinds of organic solvents (= IPA + DIW) in the vertical direction. The rinse liquid constituting the remaining liquid diffuses between these liquid layers, becoming a non-remaining liquid. In this state, a drying process of the processing fluid based on a supercritical state is performed.

Description

TECHNICAL FIELD

[0001] The present application relates to a technique of drying a substrate in a processing chamber, and particularly to a process of processing a substrate covered with a liquid film using a processing fluid in a supercritical state.

[0002] The disclosure in the specification, drawings, and claims of Japanese Patent Application is hereby incorporated by reference in its entirety:

[0003] JP Application No. 2023-138194 (filed on August 28, 2023). BACKGROUND

[0004] A processing procedure of various substrates such as semiconductor substrates, glass substrates for display devices, and the like includes a procedure of processing a surface of a substrate using various processing fluids. Since the past, wet processing using a liquid such as a chemical liquid or a rinse liquid as a processing fluid has been widely performed. In recent years, 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. This is particularly advantageous in drying processing of a substrate having a patterned surface on which a fine pattern is formed. This is because a processing fluid in a supercritical state has a property of having a low surface tension and entering a deep gap of a pattern compared to a liquid. By using the processing fluid, drying processing can be efficiently performed. In addition, it is also possible to reduce the risk of occurrence of pattern collapse due to surface tension at the time of drying.

[0005] For example, in a substrate processing system described in JP Publication No. 2013-201302, a substrate developing device is provided as an example of the "wet processing device" of the present application. In the substrate developing device, as a final processing in the device, IPA (isopropyl alcohol) liquid as an example of the "organic solvent" of the present application is supplied to a substrate wetted with a rinse liquid. Thereby, IPA replacement is performed, and the rinse liquid is removed from the surface of the substrate. In addition, a liquid-accumulation (liquid accumulation) state in which the IPA liquid is stacked on the surface of the substrate is formed. That is, a liquid film containing the IPA liquid is formed in a paddle shape. As a result, the surface of the substrate is maintained in a state wetted with the IPA liquid. Then, the substrate is carried to a substrate drying device as an example of the "supercritical processing device" of the present application by a substrate carrying device while maintaining the liquid-accumulation state, and drying processing based on a processing fluid in a supercritical state is performed on the substrate. SUMMARY

[0006] In a wet processing apparatus such as a substrate developing apparatus or a substrate cleaning apparatus, it is desirable to completely discharge a liquid such as a rinse liquid from the inside of a pattern by IPA displacement. However, sometimes the liquid remains on the inner bottom surface of the pattern. If the substrate is carried into a substrate drying apparatus (supercritical processing apparatus) in a state where the liquid remains as described above (hereinafter referred to as "residual liquid") remains, and supercritical drying processing is performed, sometimes the following problem occurs. That is, displacement of the liquid component constituting the liquid film from the processing fluid in a supercritical state is not easily complete. Therefore, in order to cope with this problem, a countermeasure is considered in which the amount of use of the processing fluid is increased. However, this results in an increase in the running cost, and causes a large environmental burden to society.

[0007] In addition, sometimes even if the amount of use of the processing fluid is increased, the residual liquid remains directly on the inner bottom surface of the pattern, which becomes a factor of pattern collapse. For this reason, the presence of the residual liquid becomes one of the main causes of a decrease in product yield.

[0008] The present application has been made in view of the above-described problems, and an object thereof is to provide a technology in which, in a substrate processing system in which a substrate in a state where an organic solvent is stacked on the surface of the substrate subjected to wet processing is carried from a wet processing apparatus to a supercritical processing apparatus, and the substrate is dried using a processing fluid in a supercritical state, it is possible to improve the yield while reducing the consumption amount of the processing fluid and reducing the environmental burden.

[0009] One aspect of the present application is a substrate processing method of processing a substrate having a pattern formation surface on which a pattern is formed, the substrate processing method including: (a) a process of sequentially performing, in a wet processing apparatus, a chemical liquid treatment of supplying a chemical liquid to the pattern formation surface to process the substrate, a preliminary organic solvent supply treatment of supplying an organic solvent to the pattern formation surface, a rinse treatment of supplying a rinse liquid to the pattern formation surface, a displacement treatment of supplying the organic solvent to the pattern formation surface, and a liquid stacking treatment of stacking the organic solvent on the pattern formation surface; (b) a process of carrying the substrate from the wet processing apparatus to a supercritical processing apparatus while maintaining a liquid stacking state in which the organic solvent is stacked on the pattern formation surface by the liquid stacking treatment; and (c) a process of drying the substrate in the supercritical processing apparatus by bringing the pattern formation surface in the liquid stacking state into contact with a processing fluid in a supercritical state.

[0010] Another aspect of the present invention is a substrate processing system for processing a substrate having a pattern forming surface on which a pattern is formed. The substrate processing system comprises: a wet processing apparatus that sequentially performs a liquid treatment of the substrate by supplying a liquid solution to the pattern forming surface, a pre-solvent supply treatment by supplying an organic solvent to the pattern forming surface, a rinsing treatment by supplying a rinsing solution to the pattern forming surface, a displacement treatment by supplying an organic solvent to the pattern forming surface, and a liquid stacking treatment in which an organic solvent is stacked on the pattern forming surface; a supercritical processing apparatus that dries the substrate by contacting the liquid stacked pattern forming surface with a supercritical processing fluid; and a substrate conveying apparatus that conveys the substrate from the wet processing apparatus to the supercritical processing apparatus while maintaining the liquid stacked state.

[0011] Conventionally, in wet processing apparatuses, after chemical treatment by supplying a chemical solution to the pattern forming surface, rinsing, displacement, and stacking processes are performed sequentially. Consequently, rinsing fluid sometimes remains on the inner bottom surface of the pattern. This residue contributes to increased consumption of processing fluids or decreased product yield. Therefore, in this invention, a preparatory organic solvent supply process is performed between the chemical treatment and the rinsing process. Thus, even if rinsing fluid remains within the pattern, the residue is not located on the inner bottom surface of the pattern, but rather as will be explained later. Figure 7 As shown in (b), the substrate is positioned by two liquid layers in the vertical direction. The lower vertical liquid layer is either a layer of organic solvent used in the preparatory organic solvent supply process or a mixture of the organic solvent and the rinsing liquid. The other liquid layer is either a layer of organic solvent used in the displacement process or a mixture of the organic solvent and the rinsing liquid. Therefore, until the substrate in its liquid-packed state is transported to the supercritical processing apparatus and comes into contact with the supercritical processing fluid, the rinsing liquid constituting the residual liquid diffuses between adjacent liquid layers in the vertical direction and mixes with the organic solvent. As a result, a drying process based on the supercritical processing fluid is performed with no residual liquid on the inner bottom surface of the pattern, i.e., a so-called residue-free state.

[0012] Invention Effects

[0013] As described above, the present invention enables supercritical drying processing with no residue. As a result, it reduces the consumption of processing fluids and increases yield.

[0014] The plurality of components possessed by the aspects of the present application described above are not all necessary, and in order to solve part or all of the problems described above, or to achieve part or all of the effects described in this specification, it is possible to change, delete, replace with a new other component, delete part of the limitation content, with respect to part of the plurality of components. In addition, in order to solve part or all of the problems described above, or to achieve part or all of the effects described in this specification, it is also possible to combine part or all of the technical features included in one aspect of the present application described above with part or all of the technical features included in another aspect of the present application described above as an independent one mode of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a diagram showing an outline configuration of a substrate processing system according to a first embodiment of the present application.

[0016] Figure 2A is a side view showing an overall configuration of a wet processing apparatus.

[0017] Figure 2B is a diagram for explaining the operation of the wet processing apparatus.

[0018] Figure 3 is a diagram schematically showing the configuration and operation of a chuck pin.

[0019] Figure 4 is a side view showing the configuration of a supercritical processing apparatus.

[0020] Figure 5 is a perspective view showing the configuration of a support tray.

[0021] Figure 6 is a flowchart showing an outline of the processing performed by the substrate processing system according to the first embodiment.

[0022] Figure 7 is a diagram schematically showing the difference in the liquid film configuration due to the presence or absence of a preliminary organic solvent supply process.

[0023] Figure 8 is a diagram showing the change in pressure in the processing chamber.

[0024] Figure 9 is a flowchart showing the operation of a substrate processing system according to a second embodiment of the present application.

[0025] In the drawings, the reference signs are as follows:

[0026] 1 substrate processing system

[0027] 2 wet processing apparatus

[0028] 3 substrate conveyance device

[0029] 4 supercritical processing device

[0030] 9 control device

[0031] 95 wet processing control section

[0032] 96 conveyance control section

[0033] 97 supercritical processing control section

[0034] AX rotational axis

[0035] LF liquid film

[0036] LL2, LL4 liquid layer (= IPA + DIW)

[0037] LL3 liquid film (= DIW)

[0038] PT pattern

[0039] S substrate

[0040] Sa surface (pattern formation surface)

[0041] Z vertical directionDETAILED DESCRIPTION

[0042] Figure 1 Fig. 1 is a diagram showing an outline configuration of a first embodiment of a substrate processing system of the present application. The substrate processing system 1 is, for example, a processing system for supplying a processing liquid to a surface of a variety of substrates such as a semiconductor wafer and performing wet processing on the substrate, and thereafter drying the substrate, and has a system configuration preferred for carrying out a substrate processing method of the present application. The main configuration of the substrate processing system 1 has a wet processing device 2, a substrate conveyance device 3, a supercritical processing device 4, and a control device 9.

[0043] The wet processing device 2 receives a substrate to be processed and performs a prescribed wet processing. The content of the processing is not particularly limited. The wet processing includes a developing processing using a chemical liquid or a cleaning processing for cleaning the substrate, and the like, performed by the above-described conventional device, and forms a liquid-heap state in which an organic solvent such as an IPA liquid is heaped on a pattern formation surface of the substrate. The substrate conveyance device 3 conveys the substrate from the wet processing device 2 while maintaining the liquid-heap state, and conveys the substrate to the supercritical processing device 4. The supercritical processing device 4 performs a drying processing (supercritical drying processing) using a processing fluid in a supercritical state with respect to the substrate conveyed therein. These are provided in a clean room. Therefore, the substrate conveyance device 3 conveys the substrate S in an ambient gas, atmospheric pressure.

[0044] The control device 9 controls the operation of each of these devices to achieve a prescribed process. For this purpose, the control device 9 has a CPU 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 process data. The storage 93 stores control programs executed by the CPU 91. The interface 94 exchanges information with a user or an external device. The operation of the devices described later is achieved by the CPU 91 executing control programs written in advance to the storage 93, causing each part of the devices to perform prescribed operations.

[0045] The control device 9 is caused to function as a wet process control section 95 that controls the operation of the wet process device 2, a conveyance control section 96 that controls the operation of the substrate conveyance device 3, a supercritical process control section 97 that controls the operation of the supercritical process device 4, and the like by the CPU 91 executing prescribed control programs. In addition, at least a part of each of these functional blocks can also be configured using dedicated hardware.

[0046] As the "substrate" in the present embodiment, various substrates such as semiconductor wafers, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, substrates for FEDs (Field Emission Displays), substrates for optical disks, substrates for magnetic disks, and substrates for optical magnetic disks can be applied. Hereinafter, a substrate processing device used for processing of a disc-shaped semiconductor wafer will be mainly described with reference to the drawings. However, the processing of the various substrates exemplified above can also be applied. In addition, various shapes of substrates can also be applied.

[0047] In addition, in the following description, a substrate having a pattern formed on only one main surface will be exemplified. Here, the side of the main surface on which the pattern and the like are formed will be referred to as the "front surface", and the side of the main surface 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.

[0048] Figure 2A and Figure 2B is a view showing a configuration example of the wet process device. More specifically, Figure 2A is a side view showing the overall configuration of the wet process device, Figure 2B is a view for explaining the operation of the wet process device. The wet process device 2 is a device that processes a substrate S by supplying a process liquid to the front surface of the substrate. The operation of the wet process device 2 is controlled by the wet process control section 95 of the control device 9.

[0049] The wet processing apparatus 2 supplies a processing liquid to the surface (pattern formation surface) Sa of the substrate S for various processes (liquid medicine processing, preliminary organic solvent supply processing, rinsing processing, replacement processing, liquid film formation processing, and the like) to be described later in detail. For this purpose, the wet processing apparatus 2 has a substrate holding portion 21, a splash guard 22, and processing liquid supply portions 23, 24 inside the processing chamber 200. These operations are controlled by a wet processing control portion 95 provided in the control apparatus 9. The substrate holding portion 21 is provided with a rotary chuck 211 having a circular plate shape with substantially the same diameter as the substrate S, and a plurality of chuck pins 212 are provided at the peripheral portion of the rotary chuck 211.

[0050] Figure 3 is a view schematically showing the configuration and operation of the chuck pin, and (a) in the same figure shows the chuck pin in the engaged state (clamped state), and (b) in the same figure shows the chuck pin in the disengaged state (released state). Although not shown in the drawing, in the present embodiment, 12 chuck pins 212 are provided radially around the rotational axis AX of the rotary chuck 211. Each of the chuck pins 212 is disposed movably in the radial direction D on the upper surface of the peripheral portion of the rotary chuck 211. The "radial direction D" referred to here means the longitudinal direction of the imaginary line connecting the rotational axis AX and the chuck pin 212.

[0051] The plurality of chuck pins 212 have the same configuration. Therefore, hereinafter, the configuration of one chuck pin 212 will be described, and the same reference numerals will be assigned to the respective portions of the other chuck pins 212, and the description thereof will be omitted. The chuck pin 212 has a chuck abutment surface 212a as shown in Figure 3 The chuck abutment surface 212a is movable in the radial direction D on the upper surface of the peripheral portion of the rotary chuck 211. Above the chuck abutment surface 212a, the chuck pin 212 has a lower abutment surface 212b. The lower abutment surface 212b is inclined downward as it approaches the direction (+D) toward the rotational axis AX. Above the end portion of the lower abutment surface 212b in the (-D) direction, a curved abutment surface 212c is provided upward. The curved abutment surface 212c is finally formed as a curved surface toward the rotational axis AX. Further, above the upper end of the curved abutment surface 212c, an upper abutment surface 212d is provided extending upward. The upper abutment surface 212d is inclined upward as it approaches the direction (+D) toward the rotational axis AX. More specifically, as shown in Figure 3As shown, the curved abutment surface 212c is directly continuous with the upper abutment surface 212d and the lower abutment surface 212b in a state disposed between the upper abutment surface 212d and the lower abutment surface 212b. Therefore, if the substrate abutment site 212e, at which the upper abutment surface 212d, the curved abutment surface 212c, and the lower abutment surface 212b are continuous and abut against the substrate S, is viewed from a horizontal direction orthogonal to the radial direction D, the substrate abutment site 212e has a substantially C-shaped shape. That is, the chuck pin 212 is capable of reciprocating along the radial direction D in a state in which the substrate abutment site 212e is directed toward the rotational axis AX.

[0052] The chuck pin 212 is connected to a chuck drive section 215. The chuck drive section 215 moves the chuck pin 212 in the radial direction D in accordance with an instruction from the wet processing control section 95. For example, at the time of handover of the substrate S between the substrate transfer device 3 and the substrate processing device 1, as shown in (b) of FIG. 10, the chuck drive section 215 moves the chuck pin 212 in the direction (-D) to position it in the non-engagement position. At this time, the curved abutment surface 212c and the upper abutment surface 212d are separated from the rotational axis AX by a distance slightly greater than the radius of the substrate S. On the other hand, the lower abutment surface 212b is positioned below the substrate S. Therefore, the substrate S is supported only by the lower abutment surface 212b as shown in (b) of FIG. 10, and is supported at a position in the lower abutment surface 212b separated from the curved abutment surface 212c in the direction (+D). Figure 3

[0053] On the other hand, at the time of engagement of the substrate S, as shown in (a) of FIG. 10, the chuck drive section 215 moves the chuck pin 212 in the direction (+D) to position it in the engagement position. By moving the chuck pin 212 from the non-engagement position to the engagement position in this way, the support position of the substrate S at the lower abutment surface 212b is displaced in the direction (-D). If the movement of the chuck pin 212 to the engagement position is completed, the substrate S is supported by the lower abutment surface 212b, the curved abutment surface 212c, and the upper abutment surface 212d. That is, the engagement of the substrate is completed. Figure 3

[0054] At the time of release of the engagement of the substrate S, the chuck pin 212 is moved in the reverse order to the above, and the support position of the substrate S at the lower abutment surface 212b is displaced in the direction (+D).

[0055] ​​Furthermore, by moving the support position of the substrate S on the lower abutment surface 212b radially D, the height position of the substrate S in the vertical direction Z is displaced by only a distance dz. Therefore, if the wet processing control unit 95 gives the chuck drive unit 215 a reciprocating movement command, the chuck pin 212 reciprocates radially D and synchronously and repeatedly raises and lowers the substrate S. That is, it is possible to provide vibration in the vertical direction relative to the substrate S. In addition, in this embodiment, the object of the present invention is achieved by utilizing this vibration addition. In this regard, a chuck pin 212 capable of vibration addition is used, but a conventional chuck pin without vibration addition function can also be used.

[0056] Return to Figure 2A as well as Figure 2B The configuration of the wet processing apparatus 2 will continue to be described. The rotary chuck 211 is supported by a rotary spindle 213 extending downwards from the center of its lower surface, ensuring its upper surface is horizontal. The rotary spindle 213 is supported by a rotary mechanism 214 mounted at the bottom of the processing chamber 200. The rotary mechanism 214 contains a rotary motor (not shown), which rotates according to control commands from the control device 9, causing the rotary chuck 211, directly connected to the rotary spindle 213, to rotate about the rotation axis AX, indicated by a dashed line. In Figure 2, the vertical direction is indicated by the up-down direction. Thus, the substrate S maintains a horizontal orientation while rotating about the rotation axis AX.

[0057] A splash guard 22 is provided to surround the substrate holding portion 21 from the side. The splash guard 22 has a generally cylindrical cup portion 221 that covers the periphery of the rotating chuck 211, and a liquid receiving portion 222 located below the outer periphery of the cup portion 221. The cup portion 221 moves up and down according to control commands from the control device 9. The cup portion 221 moves up and down between a lower position and an upper position, such as the lower position... Figure 2A The upper end of the cup portion 221 is lowered to a position below the periphery of the substrate S held in the rotating chuck 211, as shown in the figure. Figure 2B The upper end of the cup portion 221 is located above the periphery of the substrate S.

[0058] When the cup portion 221 is in the lower position, such as Figure 2A As shown, the substrate S held by the rotary chuck 211 is in a state where it protrudes outward toward the cup portion 221. For this purpose, for example, it is to prevent the cup portion 221 from causing an obstruction when the substrate S is being moved into and out of the rotary chuck 211.

[0059] Additionally, when the cup portion 221 is in the upper position, such as Figure 2BAs shown, the peripheral portion of the substrate S, held by the rotating chuck 211, is surrounded. This prevents the processing liquid ejected from the peripheral portion of the substrate S during the liquid supply process (described later) from splashing into the processing chamber 200, and allows for reliable recovery of the processing liquid. Specifically, droplets of processing liquid ejected from the peripheral portion of the substrate S by rotating the substrate S adhere to the inner wall of the cup portion 221 and flow downwards, where they are collected and recovered by the liquid receiving portion 222 located below the cup portion 221. Multiple cup portions are provided concentrically for the independent recovery of various processing liquids.

[0060] The processing fluid supply unit 23 has a structure in which a nozzle 234 is mounted at the front end of an arm 233 that extends horizontally from a rotating main shaft 232 rotatably mounted relative to a base 231 fixed to the processing chamber 200. By rotating the rotating main shaft 232 according to a control command from the control device 9, the arm 233 is rocked, and the nozzle 234 at the front end of the arm 233... Figure 2A The retraction position shown is the one that retracts laterally from the top of the substrate S, and as shown in the figure. Figure 2B The processing position above the substrate S shown moves between different locations.

[0061] Nozzle 234 is connected to processing liquid supply source 238. When appropriate processing liquid is supplied from processing liquid supply source 238, processing liquid is sprayed from nozzle 234 toward substrate S. Figure 2B As shown, while rotating the rotating chuck 211 at a relatively low speed to rotate the substrate S, a processing liquid L1 is supplied from a nozzle 234 positioned above the center of rotation of the substrate S, thereby treating the surface Sa of the substrate S with the processing liquid L1. The processing liquid L1 can be any liquid with various functions such as a chemical solution (developer, etchant, cleaning solution, etc.) and a rinsing solution; its composition is arbitrary. Furthermore, multiple processing liquids can be combined to perform the processing.

[0062] Another set of processing liquid supply units 24 also has a configuration corresponding to the first processing liquid supply unit 23 described above. That is, the second processing liquid supply unit 24 has a base 241, a rotating spindle 242, an arm 243, a nozzle 244, etc., which are the same as the configuration corresponding to the first processing liquid supply unit 23. The rotating spindle 242 rotates according to the control command from the control device 9, thereby causing the arm 243 to rock. The nozzle 244 at the front end of the arm 243 supplies processing liquid relative to the surface Sa of the substrate S.

[0063] In this embodiment, the second processing liquid supply unit 24 is used to perform preparatory organic solvent supply processing, displacement processing, and liquid film formation processing. That is, the substrate S after wet processing is transported to the supercritical processing apparatus 4 to undergo supercritical drying processing, but in order to prevent the surface of the substrate S from being exposed and oxidized during transport, or the fine patterns formed on the surface from collapsing, the substrate S is transported with its surface covered by a paddle-shaped liquid film.

[0064] As the liquid constituting the liquid film, a substance having a smaller surface tension than the main component of the treatment liquid used in the chemical liquid treatment, i.e., water, such as an organic solvent such as isopropyl alcohol (IPA) or acetone, is used. These organic solvents are supplied from the organic solvent supply source 248.

[0065] In addition, in the present embodiment, the organic solvent is supplied from the second treatment liquid supply section 24 to the substrate S not only at the time of the liquid film formation treatment but also at the time of the preparatory organic solvent supply treatment. This is for the purpose of removing the residual liquid, and will be described later with reference to FIG. 6. Figure 6 and Figure 7 A detailed description thereof will be given.

[0066] Here, two sets of treatment liquid supply sections are provided in the wet treatment device 2, but the number of sets of treatment liquid supply sections, the configuration thereof, and the function thereof are not limited thereto. For example, the treatment liquid supply sections can be only one set, and three or more sets can also be provided. In addition, one treatment liquid supply section can have a plurality of nozzles. For example, a plurality of nozzles can be provided at the tip of one arm section. In addition, as such, not only a configuration in which the nozzles spray the treatment liquid in a state of being positioned at a prescribed position can be included, but also a configuration in which the nozzles spray the treatment liquid while scanning along the surface Sa of the substrate S can be included.

[0067] Returning to Figure 1 , the description will be continued. The substrate transfer device 3 is provided with a transfer robot 30 having a hand section 31 at the tip of an arm section that is freely stretchable and rotatable. The hand section 31 can support the substrate S by coming into partial contact with the back surface of the substrate S, as will be described later with reference to FIG. 5. Figure 1 As shown by the broken line, the hand section 31 is freely movable in and out with respect to both the wet treatment device 2 and the supercritical treatment device 4. Thus, the substrate can be carried in and out with respect to the wet treatment device 2 and the supercritical treatment device 4, respectively. The operation of the transfer robot 30 is controlled by the transfer control section 96 of the control device 9. Such a transfer robot has many known technologies, and in the present embodiment, it can be appropriately selected and used, and thus a detailed description thereof will be omitted.

[0068] Figure 4 is a side view showing the configuration of the supercritical treatment device. The supercritical treatment device 4 is a device that performs a drying treatment using a treatment fluid in a supercritical state with respect to the substrate S after the wet treatment. More specifically, the supercritical treatment device 4 is a device for receiving the substrate S after the wet treatment, discharging the treatment fluid after replacing the liquid remaining on the substrate S with the treatment fluid in a supercritical state, and thereby finally bringing the substrate S to a dry state.

[0069] The supercritical processing apparatus 4 has a processing unit 41, a transfer unit 43, and a supply unit 45. The processing unit 41 becomes the main body of execution of supercritical drying processing. The transfer unit 43 receives the substrate S after wet processing, which is carried by the substrate carrying apparatus 3, and carries it into the processing unit 41, and delivers the processed substrate S from the processing unit 41 to the carrying apparatus outside. The supply unit 45 supplies chemicals, power, and energy, and the like necessary for processing to the processing unit 41 and the transfer unit 43. These operations are controlled by the control device 9, particularly by the supercritical processing control section 97.

[0070] The processing unit 41 has a configuration in which a processing chamber 412 is installed above a pedestal 411. The processing chamber 412 is composed of a combination of several metal blocks, the inside of which is a hollow, and constitutes a processing space SP. The substrate S as a processing target is carried into the processing space SP and subjected to processing. An opening 421 in the form of a slit extending long in the X direction is formed in the (-Y) side surface of the processing chamber 412. The processing space SP is communicated 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 has a cross-sectional shape long in the X direction and short in the Z direction, and is a hollow extending in the Y direction.

[0071] In the (-Y) side surface of the processing chamber 412, a cover member 413 is provided in a manner to close the opening 421. The cover member 413 closes the opening 421 of the processing chamber 412, thereby constituting a hermetic processing container. Thus, processing under high pressure can be performed with respect to the substrate S in the processing space SP inside. In the (+Y) side surface of the cover 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 cover member 413 is supported so as to be freely movable horizontally in the Y direction by a support mechanism, which is omitted from the illustration.

[0072] The cover member 413 is movable in and out with respect to the processing chamber 412 by a movement-in-and-out mechanism 453 provided in the supply unit 45. Specifically, the movement-in-and-out mechanism 453 has, for example, a linear motor, a direct-acting guide rail, a ball screw mechanism, a solenoid valve, an air cylinder, or the like. Such a direct-acting mechanism moves the cover member 413 in the Y direction. The movement-in-and-out mechanism 453 operates according to a control command from the control device 9.

[0073] The lid member 413 is separated from the processing chamber 412 by moving in the (-Y) direction, as shown by the dotted line, and the support tray 415 can be accessed if it is pulled out to the outside from the processing space SP through the opening 421. That is, the substrate S can be placed on the support tray 415, and the substrate S placed on the support tray 415 can be taken out. 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.

[0074] Figure 5 is a perspective view showing the configuration of the support tray. The support tray 415 has a tray member 416 and a plurality of support pins 417. The tray member 416 has, for example, a configuration in which a recessed portion 418 having a diameter corresponding to the planar dimension of the substrate S, more specifically, a diameter slightly larger than the diameter of the circular substrate S, is provided on the horizontal and flat upper surface of a flat-plate-shaped configuration body.

[0075] The recessed portion 418 extends locally to the side surface of the tray member 416. That is, the side wall surface of the recessed portion 418 is not circular but is locally cut away. Therefore, in the cut-away portion, a part of the bottom surface 418a of the recessed portion 418 is directly connected to the side surface. In this example, such cut-away portions are provided at both ends in the X direction and the (+Y) direction end of the support tray 415, and in these portions, the bottom surface 418a is directly connected to the side surface.

[0076] In addition, a through-hole 419 for the lift pin 437 of the transfer unit 43 to be inserted therethrough is provided at a position in the bottom surface 418a corresponding to the lift pin 437. By passing the lift pin 437 through the through-hole 419 and lifting it, a state in which the substrate S is housed in the recessed portion 418 and a state in which it is lifted upward in this state are realized.

[0077] A plurality of support pins 417 are arranged at the peripheral portion of the recessed portion 418. The number of support pins 417 is arbitrary, but from the viewpoint of stably supporting the substrate S, it is preferable to provide three or more. In the present embodiment, three support pins 417 are installed to the tray member 416 in a manner of surrounding the bottom surface 418a when viewed from above. Figure 5 As shown in the partial enlarged view in (b) of FIG. 4, the support pin 417 has a height restriction portion 417a and a horizontal position restriction portion 417b.

[0078] The upper surface of the height restriction site 417a is flat, and by abutting against the peripheral portion of the back surface of the substrate S, the substrate S is supported and its position in the vertical direction Z (hereinafter referred to as "height position") is shown. On the other hand, the horizontal position restriction site 417b extends to a position above the upper end of the height restriction site 417a, and abuts against the side surface of the substrate S, thereby restricting the position of the substrate S in the horizontal direction (XY direction). With this support pin 417, the substrate S is supported in a horizontal posture in which the bottom surface 418a of the recessed portion 418 is opposed to the substrate S and separated upward from the bottom surface 418a.

[0079] The lid member 413 closes the opening 421 by moving in the (+Y) direction, and seals the processing space SP. A seal member 422 is provided between the (+Y) side surface of the lid member 413 and the (-Y) side surface of the processing chamber 412, and maintains the airtight state of the processing space SP. The seal member 422 is made of rubber, for example. In addition, the lid member 413 is fixed with respect to the processing chamber 412 by a lock mechanism not shown. As such, in the present embodiment, the lid member 413 is switched between a closed state (solid line) in which the opening 421 is closed and the processing space SP is sealed, and a separated state (dotted line) in which the opening 421 is largely separated and the substrate S can be brought in and out.

[0080] In a state in which the airtight state 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 portion 457 of the supply unit 45 sends out a processing fluid, such as carbon dioxide, which is a substance that can be used for supercritical processing, as a processing fluid, and further pressurizes the processing fluid in the processing chamber 412, thereby achieving a supercritical state. The processing fluid is supplied to the processing unit 41 in a gaseous or liquid state. Carbon dioxide is a chemical substance that is preferable for supercritical dry processing because it becomes a supercritical state at a relatively low temperature and low pressure, and has a property of dissolving an organic solvent that is commonly used for substrate 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.

[0081] The processing fluid is filled into the processing space SP, and when the processing space SP reaches 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 using the processing fluid in a supercritical state. The fluid supply portion 457 and the fluid recovery portion 455 are controlled by the supercritical processing control portion 97.

[0082] The processing space SP has a shape and a volume capable of accepting the support tray 415 and the substrate S supported by the support tray 415. That is, the processing space SP has a substantially rectangular cross-sectional shape larger in the horizontal direction than the width of the support tray 415 and larger in the vertical direction than the height of the support tray 415 and the substrate S taken together, and a depth capable of accepting the support tray 415. The processing space SP has a shape and a volume capable of accepting only the support tray 415 and the substrate S as such. 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 the processing fluid required to fill the processing space SP is small enough.

[0083] The fluid supply portion 457 supplies the processing fluid to the processing space SP on the (+Y) side relative to the (+Y) side end portion of the substrate S. On the other hand, the fluid recovery portion 455 discharges the processing fluid flowing in the space above the substrate S and the space below the support tray 415 in the processing space SP on the (-Y) side relative to the (-Y) side end portion of the substrate S. Thereby, in the processing space SP, the laminar flow of the processing fluid is formed from the (+Y) side toward the (-Y) side above the substrate S and below the support tray 415, respectively.

[0084] The supercritical processing control portion 97 of the control device 9 determines the pressure and the temperature in the processing space SP based on the detection results of a detection portion not shown, and controls the fluid supply portion 457 and the fluid recovery portion 455 based on the results thereof. Thereby, the supply of the processing fluid to the processing space SP and the discharge of the processing fluid from the processing space SP are appropriately managed, and adjusted according to the processing recipe for achieving the prescribed pressure and the temperature in the processing space SP.

[0085] The transfer unit 43 is responsible for the handover of the substrate S between the substrate conveyance device 3 and the support tray 415. To achieve this, the transfer unit 43 has a main body 431, a lifting member 433, a base member 435, and a plurality of lifting pins 437. The lifting member 433 is a columnar member extending in the Z direction, and is supported so as to be movable in the Z direction relative to the main body 431 by a support mechanism not shown. The base member 435 having a substantially horizontal upper surface is installed at the upper portion of the lifting member 433. The plurality of lifting pins 437 are erected upward from the upper surface of the base member 435. The lifting pins 437 respectively support the substrate S in a horizontal posture from below by abutting the upper end portions thereof against the back surface of the substrate S. In order to stably support the substrate S in a horizontal posture, it is preferable to provide three or more lifting pins 437 having upper end portions equal in height to each other.

[0086] The lift member 433 is capable of being lifted by a lift mechanism 451 provided to the supply unit 45. Specifically, the lift mechanism 451 has, for example, a linear motor, a direct drive guide, a ball screw mechanism, a solenoid valve, a pneumatic cylinder, or the like, which is a direct drive mechanism that moves the lift member 433 in the Z direction. The lift mechanism 451 operates in accordance with a control command from the control device 9.

[0087] The base member 435 is moved up and down by the lift of the lift member 433, and the plurality of lift pins 437 are moved up and down integrally therewith. By this, the substrate S is exchanged between the transfer unit 43 and the support tray 415. More specifically, as shown by the broken line, the substrate S is exchanged while the support tray 415 is pulled out to the outside of the chamber. In order to achieve this, the support tray 415 is provided with a through hole 419 for the lift pins 437 to be inserted therethrough. When the base member 435 is raised, the upper ends of the lift pins 437 pass through the through hole 419 to above the upper surface of the support tray 415. In this state, the substrate S, which is carried by the transfer robot 30, is exchanged with respect to the lift pins 437 from the hand 31 of the transfer robot 30. By lowering the lift pins 437, the substrate S is exchanged from the lift pins 437 to the support tray 415. The carry-out of the substrate S can be performed in the reverse order to the above. Figure 5

[0088] Figure 6 is a flowchart showing an outline of processing performed by the substrate processing system of the first embodiment. The substrate processing system 1 receives a substrate S as a processing target, and sequentially performs wet processing using a processing liquid such as a chemical liquid, a rinse liquid, and an organic solvent, a carry-in process of carrying the substrate S, which has been subjected to the wet processing, from the wet processing device 2 to the supercritical processing device 4, and supercritical dry processing using a supercritical processing fluid. Specifically, when the substrate S as the processing target is housed in the wet processing device 2 (step S10) that constitutes the substrate processing system 1, the wet processing (step S20), the carry-in process (step S30), and the supercritical dry processing (step S40) are sequentially performed.

[0089] ​The wet processing apparatus 2 performs wet processing on the substrate S using a prescribed processing liquid (step S20). In the present embodiment, on the basis of the conventional chemical liquid processing (step S21), the rinsing processing (step S23), the displacement processing (step S24), and the liquid film formation processing (step S25), the preliminary organic solvent supply processing (step S22) of supplying the above-described organic solvent is also performed. The preliminary organic solvent supply processing is performed between the chemical liquid processing and the rinsing processing. That is, after the prescribed chemical liquid processing is performed by supplying a chemical liquid such as a developer or a rinsing liquid in step S21 in the wet processing, an organic solvent such as IPA or acetone is supplied to the surface Sa of the substrate S (step S22). Next, a rinsing liquid such as DIW (De-ionized water) is supplied to the surface Sa of the substrate S, and an organic solvent such as IPA is supplied to the substrate S, whereby the rinsing liquid adhering to the surface Sa of the substrate S is displaced by the organic solvent (step S24), and a liquid film state in which the organic solvent is stacked is formed. That is, a liquid film LF is formed on the surface Sa of the substrate S (step S25: liquid film formation processing).

[0090] Here, referring to Figure 7 the significance of the liquid film formation processing and the technology of the preliminary organic solvent supply processing will be described. Figure 7 is a diagram schematically showing the difference in the constitution of the liquid film due to the presence or absence of the preliminary organic solvent supply processing, Figure 7 column (a) shows the prior art in which the preliminary organic solvent supply processing is not performed, and column (b) shows the embodiment in which the preliminary organic solvent supply processing is performed. For example Figure 7 As shown in FIG. 8, when DIW is present inside the pattern PT formed on the surface Sa of the substrate S, collapse of the pattern PT due to the surface tension of the DIW is feared. In addition, sometimes a watermark remains on the surface Sa of the substrate S due to incomplete drying. Furthermore, sometimes deterioration such as oxidation occurs due to contact of the surface Sa of the substrate S with the outside air. In order to prevent such problems, the surface Sa of the substrate S is covered with an organic solvent. As the organic solvent, a liquid having a lower surface tension than that of DIW and a lower corrosiveness to the substrate S, such as a solvent having a mutual solubility with respect to DIW, for example, IPA, acetone, or the like, is preferably used. Hereinafter, a case in which DIW is used as the rinsing liquid and IPA is used as the organic solvent will be described.

[0091] Here, when the displacement into IPA is performed well, the liquid film LF is constituted only with IPA, or with a mixture of IPA and DIW. In this case, DIW does not remain on the inner bottom surface of the pattern PT. However, in reality, as in the prior example Figure 7(a) as shown, sometimes a residual liquid (DIW) remains on the inner bottom surface of the pattern PT. The specific gravity of this residual liquid is greater than that of the organic solvent, and it easily remains on the inner bottom surface of the pattern PT.

[0092] To this end, in the present embodiment, IPA is supplied to the surface Sa of the substrate S between the chemical liquid treatment (step S21) and the rinse treatment (step S22). Thereby, in the pattern PT, the following five liquid layers LL1 to LL5 are sequentially stacked from the inner bottom surface side thereof:

[0093] Liquid layer LL1 = an IPA layer composed of IPA used in the preparatory organic solvent supply treatment,

[0094] Liquid layer LL2 = a mixed layer of IPA used in the preparatory organic solvent supply treatment and DIW,

[0095] Liquid layer LL3 = a layer of a residual liquid composed of DIW,

[0096] Liquid layer LL4 = a mixed layer of IPA used in the displacement treatment and DIW, Liquid layer LL5 = an IPA layer composed of IPA used in the displacement treatment.

[0097] Further, there are cases where the liquid layer LL5 contains a portion of the IPA used in the liquid film formation treatment.

[0098] As such, the liquid layer LL3 (that is, the residual liquid (DIW)) within the pattern PT exists in a state sandwiched by the liquid layers LL2 and LL4 including IPA. The DIW constituting the residual liquid diffuses between the liquid layers LL2 and LL4 with each other during the period of being carried by the substrate carrying device 3 to the supercritical processing device 4 as explained next. As a result, the liquid layer LL3 composed of only the residual liquid is removed. Thereby, the liquid film LF without the residual liquid is formed on the surface Sa of the substrate S. Then, the substrate S is carried from the wet processing device 2 to the supercritical processing device 4 by the substrate carrying device 3 while maintaining the liquid-heap state (step S30).

[0099] The substrate S carried to the supercritical processing device 4 is housed in the processing chamber 412 while maintaining the liquid-heap state. Specifically, the substrate S is carried with the pattern formation surface (surface Sa) as the upper surface, and in a state where this pattern formation surface is covered with the very thin liquid film LF. As Figure 4With the lid member 413 moved to the (-Y) side and the support tray 415 pulled out as shown by a dotted line, the lift pin 437 is raised. The conveyance device hands over the substrate S to the lift pin 437. When the lift pin 437 is lowered, the substrate S is loaded in the support tray 415. When the support tray 415 and the lid member 413 are integrally moved in the (+Y) direction, the support tray 415 supporting the substrate S is housed in the processing space SP in the processing chamber 412, and the opening 421 is closed by the lid member 413.

[0100] In this state, carbon dioxide as a processing fluid is introduced into the processing space SP in a gaseous phase (step S41). When the substrate S is carried in, outside air intrudes into the processing space SP, but this is replaced by the introduction of the processing fluid in a gaseous phase. Further, the pressure in the processing chamber 412 is raised by the injection of the processing fluid in a gaseous phase.

[0101] Further, during the introduction of the processing fluid, the discharge of the processing fluid from the processing space SP is continued. That is, during the introduction of the processing fluid by the fluid supply section 457, the discharge of the processing fluid from the processing space SP by the fluid recovery section 455 is also performed. Thus, the processing fluid supplied to the processing is not left in the processing space SP but is discharged, preventing impurities such as residues remaining in the processing fluid from adhering to the substrate S again.

[0102] If the amount of the processing fluid supplied is more than the amount of the processing fluid discharged, the density of the processing fluid in the processing space SP rises, and the pressure in the chamber rises. Conversely, if the amount of the processing fluid supplied is less than the amount of the processing fluid discharged, the density of the processing fluid in the processing space SP falls, and the pressure in the chamber is reduced. As for the supply and discharge of the processing fluid to / from the processing chamber 412, these are performed based on a supply / discharge recipe created in advance. That is, the control device 9 controls the fluid supply section 457 and the fluid recovery section 455 based on the supply / discharge recipe, thereby adjusting the timing of the supply / discharge of the processing fluid and the flow rate thereof, and the like.

[0103] Figure 8 is a graph showing the change in the pressure in the processing chamber. In the case where the processing fluid is carbon dioxide, this critical temperature does not change much from the room temperature, and thus the temperature change during processing is not large. Here, the phenomenon is explained with focus on the pressure in the chamber so that the change is more noticeable. From the state where the atmosphere is opened to the processing space SP to make the internal pressure atmospheric pressure Pa, the introduction of the processing fluid is started at a time Tl after the processing space SP is closed, and the internal pressure starts to rise.

[0104] The pressurization is continued until the pressure of the processing fluid in the processing space SP rises and exceeds the critical pressure Pc (step S42). At the time T2 when the critical pressure Pc is reached in the chamber, the processing fluid becomes a supercritical state in the chamber. That is, the processing fluid is changed from a gas phase to a supercritical state due to the phase change in the processing space SP. By filling the processing space SP with the processing fluid in the supercritical state, the IPA (or the mixed fluid of IPA and DIW) covering the substrate S is replaced by the processing fluid in the supercritical state. The IPA or the like that is desorbed from the surface of the substrate S is removed from the substrate S in a state of being dissolved in the processing fluid, together with the processing fluid, and is discharged from the processing chamber 412. That is, the processing fluid in the supercritical state has a function of replacing the replacement target liquid, i.e., the IPA (or the mixed fluid of IPA and DIW) adhering to the substrate S, as a replacement target liquid, and discharging it to the outside of the processing chamber 412.

[0105] After the time T3 when the processing fluid is reliably changed to the supercritical state, the state in which the processing space SP is filled with the processing fluid in the supercritical state is continued for a prescribed time (steps S43 and S44), so that the replacement target liquid adhering to the substrate S can be completely replaced and discharged to the outside of the chamber. Further, in the case where the processing fluid in the supercritical state is used as a replacement target liquid, the processing fluid in the supercritical state is used as a replacement target liquid, and the processing fluid in the supercritical state is used as a replacement target liquid. Figure 8 In the case shown in FIG. 6, the pressure Pm in the chamber in the supercritical state is constant, but the pressure can be varied within a range that does not become the critical pressure Pc or less.

[0106] At the time T4, if the replacement of the replacement target liquid based on the processing fluid in the supercritical state in the processing chamber 412 is completed (YES in step S44), the processing fluid in the processing space SP is discharged to dry the substrate S. Specifically, the processing chamber 412 filled with the processing fluid in the supercritical state is depressurized by increasing the amount of discharge of the fluid from the processing space SP (step S45).

[0107] In the depressurization process, the supply of the processing fluid can be stopped, or a small amount of the processing fluid can be continuously supplied. By depressurizing the processing space SP from the state in which it is filled with the processing fluid in the supercritical state, the processing fluid is changed in phase from the supercritical state to a gas phase. By discharging the gaseous processing fluid to the outside, the substrate S becomes in a dry state. At this time, the depressurization rate is adjusted so that solid and liquid phases are not generated due to a rapid temperature drop. That is, after the depressurization is started at the time T4, the depressurization is performed at a relatively low depressurization rate until the time T5 when the pressure is reliably decreased to the critical pressure Pc. Thus, the processing fluid in the processing space SP is directly gaseousized from the supercritical state and is discharged to the outside.

[0108] After the moment T5 when the process fluid is completely vaporized, the decompression rate is increased, thereby enabling the decompression to atmospheric pressure Pa in a short time. In this way, during the entire period from the moment T4 when the decompression begins until T6 when the pressure in the chamber drops to atmospheric pressure Pa, the process fluid will not liquefy, thus preventing the formation of a gas-liquid interface on the substrate S exposed on the dried surface.

[0109] In this supercritical drying process, after the processing space SP is filled with a supercritical fluid, the gas phase undergoes a phase change and is discharged. This efficiently replaces the liquid adhering to the substrate S, preventing residue from remaining on the substrate S. Furthermore, the substrate can be dried without problems such as contamination caused by impurities, pattern collapse, or the formation of a gas-liquid interface.

[0110] The processed substrate S is moved to the next process (step S50). That is, by moving the cover member 413 in the (-Y) direction, the support tray 415 is pulled out from the processing chamber 412 and transferred to the external transport device via the transfer unit 43. At this time, the substrate S is in a dry state. The content of the next process is arbitrary. The processing of one substrate S is completed in this way. If there is a substrate to be processed next, return to step S10 to receive a new substrate S, and repeat the above processing.

[0111] As described above, according to the first embodiment, in the wet processing apparatus 2, after the liquid treatment (step S21), a preparatory organic solvent supply treatment (step S22), a rinsing treatment (step S23), a displacement treatment (step S24), and a liquid film formation treatment (step S25), which is an example of the "liquid stacking treatment" of the present invention, are performed sequentially. Here, even if DIW remains in the pattern PT of the pattern forming surface (surface Sa) of the substrate S in the liquid stacking state, it is as follows Figure 7 As shown in (b), the liquid layer LL3, composed of residual liquid, is sandwiched in the vertical direction by liquid layers LL2 and LL4, which are a mixture of IPA and DIW. Therefore, the DIW constituting the liquid layer LL3 diffuses between liquid layers LL2 and LL4. Specifically, there is sufficient time for the residual liquid (DIW) to diffuse between the aforementioned liquid layers LL2 and LL4 until the substrate S, in its liquid-packed state, is transported to the supercritical processing apparatus 4 and comes into contact with the supercritical processing fluid. Accordingly, through this interdiffusion, the residual liquid is mixed with the IPA. Therefore, a drying process based on the supercritical processing fluid is performed with so-called residue-free operation. This means that the supercritical processing fluid is not overused, and supercritical drying can be performed with high quality. As a result, the consumption of processing fluid can be reduced while increasing yield.

[0112] As described above, in the first embodiment, the DIW corresponds to an example of the "rinse liquid" of the present application. In addition, the IPA corresponds to an example of the "organic solvent" of the present application, and the IPA is used as the "organic solvent" in the preparatory organic solvent supply process (step S22), the displacement process (step S24), and the liquid film formation process (step S25). The surface Sa of the substrate S corresponds to the "pattern formation surface" of the present application. In addition, the steps S20, S30, S40 respectively correspond to examples of the "(a) process", the "(b) process", and the "(c) process" of the present application.

[0113] Further, in the above-described first embodiment, the substrate S is carried from the wet process apparatus 2 to the supercritical process apparatus 4 while maintaining a state in which the liquid layer LL3 corresponding to the residual liquid is sandwiched by the liquid layers LL2, LL4, so-called sandwich structure. Here, the substrate S can be additionally vibrated before the carrying, during the carrying, and / or before the supply of the process fluid in the supercritical process apparatus 4. With this vibration addition, the mutual diffusion between the DIW constituting the liquid layer LL3 and the liquid layers LL2, LL4 is promoted, and the residual liquid can be removed in a shorter time.

[0114] Figure 9 is a flowchart showing the operation of the second embodiment of the substrate processing system of the present application. In the above-described first embodiment, the chuck pin 212 has a vibration addition function in addition to the function of holding the substrate S by clamping the side end portion of the substrate S. Thus, in the second embodiment, for example, as shown in Figure 9 , the substrate S can be additionally vibrated (step S60) after the liquid film formation process (step S25) and before the substrate carrying (step S30). More specifically, after the liquid stacking state is formed in the wet process apparatus 2, the wet process control section 95 gives a reciprocating movement instruction to the chuck drive section 215. Thus, Figure 3 the engaged state shown in (a) of Figure 3 is alternately repeated with the non-engaged state shown in (b). That is, the substrate S is repeatedly raised and lowered in conjunction with the reciprocating movement of the chuck pin 212 in the radial direction D. As a result, as shown in the lower left of Figure 9 , the residual liquid (DIW) constituting the liquid layer LL3 is moved and diffused to the liquid layers LL2, LL4 with respect to the vibration in the vertical direction Z added to the substrate S, and the DIW contained in the liquid layers LL2, LL4 is also moved and diffused to the liquid layers LL1, LL5, respectively. As such, the liquid layer LL3 disappears in a shorter time compared to the first embodiment, and the DIW diffuses to the entire liquid film LF (step S60). Further, in the present specification, the process of removing the residual liquid by vibration addition as such is referred to as a "residual liquid removal process".

[0115] In addition, in the second embodiment, in order to perform the residual liquid removal processing, the chuck pin 212 functions as a vibration addition function. Therefore, a configuration dedicated to the vibration addition function is not required, and thus the device cost can be reduced.

[0116] In addition, in the second embodiment, the substrate S is vibrated in the vertical direction Z in order to perform the residual liquid removal processing, but the vibration addition mode is not limited thereto. For example, the wet processing control section 95 can impart a positive and negative rotation command to the rotation mechanism 214 while the substrate S is held by the chuck pin 212. In this case, the rotation mechanism 214 that has received the positive and negative rotation command repeatedly performs an operation of positively and negatively rotating the substrate S by a predetermined angle around the rotation axis AX, that is, repeatedly performs a turning operation. In this way, the substrate S can be vibrated by a turning operation of the substrate S in the circumferential direction.

[0117] In addition, the substrate S can be vibrated by a configuration that is additionally provided, instead of the vibration addition of the chuck pin 212 in the vertical direction Z (hereinafter referred to as "added up-down vibration") or the vibration addition of the rotation mechanism 214 in the circumferential direction (hereinafter referred to as "added turning vibration"). For example, after the liquid film formation processing (step S25), the wet processing control section 95 can operate an ultrasonic transducer provided at a position separate from the substrate holding section 21, and the substrate S can be vibrated by ultrasonic waves generated by the ultrasonic transducer. In addition, a vibrator can be installed in the substrate holding section 21 in advance, and the wet processing control section 95 can operate the vibrator after the liquid film formation processing (step S25). In these embodiments, the vibration direction of the substrate S can be controlled depending on the arrangement of the vibrator. Furthermore, as for the vibrator and the ultrasonic transducer, a conventionally known device can be used. Therefore, detailed configuration descriptions are omitted in this specification.

[0118] In addition, in the second embodiment described above, the substrate S in the liquid stacking state is vibrated in the wet processing device 2, but the substrate S can be vibrated in the substrate conveyance device 3 or the supercritical processing device 4.

[0119] For example, in the first embodiment and the fifth embodiment, the transfer robot 30 is movable in and out of both the wet processing apparatus 2 and the supercritical processing apparatus 4 while supporting the substrate S in the puddle state from the back side. Therefore, the transfer robot 30 not only has the function of transferring the substrate S in and out of the wet processing apparatus 2 and the supercritical processing apparatus 4, respectively, but also can move the hand 31 supporting the substrate S back and forth in the horizontal direction or rotate it. That is, by repeating the back-and-forth movement or the rotation of the hand 31, the substrate S can be vibrated in the horizontal direction. Then, the transfer process (step S30) from the wet processing apparatus 2 to the supercritical processing apparatus 4 can be controlled so that the transfer robot 30 sequentially performs the following three sub-processes:

[0120] • a process in which the hand 31 receives the substrate S in the puddle state,

[0121] • a process in which the hand 31 vibrates the substrate S in the puddle state by moving back and forth in the horizontal plane by a predetermined distance or rotating in the forward and reverse directions;

[0122] • a process in which the transfer robot 30 transfers the substrate S in the puddle state to the processing unit 41 of the supercritical processing apparatus 4.

[0123] Further, in this case, the residual liquid removal process is performed at the time point when the hand 31 enters the wet processing apparatus 2 and receives the substrate S in the puddle state, but the timing of performing the residual liquid removal process is not limited to this. For example, during the period in which the hand 31 stops and waits near the supercritical processing apparatus 4 while moving toward the supercritical processing apparatus 4, the residual liquid removal process can be performed.

[0124] In addition, in order to wait for the transfer of the substrate S to the supercritical processing apparatus 4 according to the operation state of the supercritical processing apparatus 4, in addition to setting the vicinity of the supercritical processing apparatus 4 as the waiting position as described above, there is a case where another waiting position is provided. For example, in a case where the substrate transfer apparatus 3 has a placement table that temporarily places the substrate S in the puddle state to wait, the placement table functions as a waiting position. Therefore, a vibrator can be installed in the placement table to vibrate the substrate S waiting in the placement table. That is, the residual liquid removal process can be performed at the waiting position where the placement table is provided.

[0125] In addition, in order to perform the residual liquid removal process, the hand 31 vibrates in the horizontal direction or rotates in the horizontal plane, but the transfer robot 30 can be configured to vibrate in another form. For example, sometimes the transfer robot 30 is configured to be able to move the hand 31 in the vertical direction Z. In this case, the hand 31 holding the substrate S in the puddle state is raised and lowered in the vertical direction Z to vibrate the substrate S.

[0126] In the first embodiment and the second embodiment, the substrate S carried to the supercritical processing apparatus 4 is housed in the processing chamber 412 while being kept in a state of being retained by liquid. Specifically, the substrate S is carried in a state in which the pattern formation surface Sa serves as the upper surface and the pattern formation surface Sa is covered with a very thin liquid film LF. As Figure 4 As shown by a dotted line, in a state in which the cover member 413 is moved to the (-Y) side and the support tray 415 is pulled out, the lift pins 437 are raised. The carrying apparatus hands over the substrate S to the lift pins 437. By lowering the lift pins 437, the substrate S is placed on the support tray 415. As such, the acceptance of the substrate S is completed.

[0127] At this point, the supercritical processing control section 97 moves the support tray 415 and the cover member 413 back and forth along the Y direction while the substrate S is kept in a state of being retained by liquid. By adding vibration to the substrate S by the back and forth movement, the residual liquid is caused to diffuse (residual liquid removal processing) as in the second embodiment.

[0128] According to this embodiment, the residual liquid removal processing is performed in the supercritical processing apparatus 4 before the processing fluid in a supercritical state contacts the substrate S. Therefore, the same effect as in the second embodiment is obtained.

[0129] In addition, in this embodiment, the support tray 415 and the cover member 413 are vibrated along the Y direction in order to perform the residual liquid removal processing, but a vibrator can be installed in the support tray 415 or the cover member 413. That is, the vibrator can be caused to operate to vibrate the substrate S according to a vibration instruction from the supercritical processing control section 97.

[0130] In addition, the residual liquid removal processing is performed before the pressure in the processing chamber 412 is increased, but the residual liquid removal processing can be performed in the pressure increase as long as it is before the supercritical condition is reached. For example, the residual liquid removal processing can be performed in a subcritical state. In particular, considering the elapsed time from the start of the residual liquid removal processing to the start of the contact with the processing fluid in a supercritical state, it is preferable to perform the residual liquid removal processing at a timing close to the subcritical state. That is, for the reason that the specific gravity of DIW is larger than that of IPA, and the like, as the above elapsed time becomes longer, a part of the DIW diffused into IPA can be deposited on the inner bottom surface of the pattern PT, resulting in an increase in the DIW concentration. In view of this, it is also preferable to set the execution timing of the residual liquid removal processing.

[0131] In addition, a step of heating the inside of the pattern can be provided instead of the above vibration addition, or the step of heating the inside of the pattern can be further provided on the basis of the above vibration addition. For example, at least one of the following means can be performed:

[0132] (a) using a rinse liquid having a temperature that can be maintained above 40°C and below the upper limit temperature of the puddle state;

[0133] (b) in parallel with the liquid film formation process (puddle process), supplying a high-temperature DIW or a fluid after heating (these will be collectively referred to as "heating medium") to the back surface Sb of the substrate S opposite the pattern formation surface Sa. Furthermore, the heating medium preferably has a temperature that can be maintained above 80°C and below the upper limit temperature of the puddle state;

[0134] (c) in parallel with the liquid film formation process (puddle process), heating the substrate S using a heater (not shown) disposed opposite the back surface Sb of the substrate S opposite the pattern formation surface Sa;

[0135] (d) while heating the substrate S received from the wet process device 2 using a heater (not shown) provided to the hand 31 of the transfer robot 30, delivering the substrate S to the supercritical process device 4 using the hand 31;

[0136] (e) in the supercritical process device 4, before contacting the substrate S with the supercritical state process fluid to supercritically dry, heating the substrate S using a heater (not shown) provided to the support tray 415.

[0137] Furthermore, the present application is not limited to the above-described embodiments, and various modifications other than those described above can be made within the scope of the gist thereof. In the above-described embodiments, IPA was used as the organic solvent in any of the preparatory organic solvent supply process (step S22), the displacement process (step S24), and the liquid film formation process (step S25). However, the combination of the organic solvents used in each process is not limited thereto, and a plurality of types can be combined. For example, acetone can be used in one of the three processes, and IPA can be used in the remaining processes.

[0138] In addition, the various chemicals used in the processes of the above-described embodiments show only some examples, and various chemicals can be used instead as long as they conform to the technical idea of the present application.

[0139] The application has been described above along with specific examples, but these descriptions are not intended to be construed in a limiting sense. Various modifications to the disclosed embodiments can be made by those skilled in the art without departing from the scope of the application. Therefore, the appended claims are intended to cover all such modifications as fall within the scope of the application.

[0140] The present application can be applied to all substrate processing methods and substrate processing systems that process a substrate covered with a liquid film using a process fluid in a supercritical state.

Claims

1. A substrate processing method for processing a substrate having a patterned surface on which a pattern is formed, the substrate processing method being characterized by comprising: (a) In a wet processing apparatus, the following steps are performed in sequence: a solution treatment of the substrate by supplying a solution to the pattern forming surface, a pre-solvent supply treatment of supplying an organic solvent to the pattern forming surface, a rinsing treatment of supplying a rinsing solution to the pattern forming surface, a replacement treatment of supplying the organic solvent to the pattern forming surface, and a liquid stacking treatment of the organic solvent on the pattern forming surface. (b) The substrate is transferred from the wet processing apparatus to the supercritical processing apparatus while maintaining the state of being piled with the organic solvent on the pattern forming surface by the piled liquid treatment. as well as (c) In the supercritical processing apparatus, the substrate is dried by bringing the patterned surface in the liquid-pile state into contact with the processing fluid in the supercritical state.

2. The substrate processing method according to claim 1, characterized in that, The organic solvent used in the preparative organic solvent supply treatment, the organic solvent used in the displacement treatment, and the organic solvent used in the heap liquid treatment are of the same type.

3. The substrate processing method according to claim 2, characterized in that, The organic solvent used in the preparative organic solvent supply process, the organic solvent used in the displacement process, and the organic solvent used in the heap liquid process are IPA, which is isopropanol.

4. The substrate processing method according to claim 1, characterized in that, It also includes a step (d), in which, before the pattern forming surface comes into contact with the supercritical state of the processing fluid, vibration is applied to the substrate while maintaining the liquid pile state, thereby mixing the rinsing liquid remaining on the pattern with the organic solvent.

5. The substrate processing method according to claim 1, characterized in that, In at least one of the steps (a), (b), and (c), the pattern is heated while maintaining a liquid-filled state.

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