Substrate processing apparatus, fluid supply system, and substrate processing method

Abstract

This substrate processing apparatus is provided with: a processing container having a processing space capable of accommodating a substrate in a state in which the surface is wetted by a liquid; and a processing fluid supply unit for supplying a processing fluid in a supercritical state to the processing container, the processing fluid supply unit comprising: a fluid supply line, one of which is connected to the fluid supply source and the other of which is connected to the processing container; a pump provided in the fluid supply line; a heating unit provided on the downstream side of the pump; a first flow rate adjustment unit provided between the pump and the heating unit; a first pressure measurement unit provided between the first flow rate adjustment unit and the heating unit; a second pressure measurement unit provided between the pump and the first flow rate adjustment unit; a branch point provided in the fluid supply line between the pump and the first flow rate adjustment unit; a connection point provided on the upstream side of the pump in the fluid supply line; a branch line connecting the branch point and the connection point; a second flow rate adjustment unit provided in the branch line; and a control unit that controls the second flow rate adjustment unit.

Description

Technical Field

[0001] The invention relates to a substrate processing device, a fluid supply system and a substrate processing method. Background Art

[0002] A substrate processing apparatus is known, which includes: a processing container that accommodates a substrate whose surface is wetted by a liquid; and a processing fluid supply unit that supplies a processing fluid in a supercritical state to the liquid (for example, see Patent Document 1). In the substrate processing apparatus, the processing fluid supply unit is controlled based on the output from a pressure sensor located downstream of the processing container.

[0003] <Prior Art Literature>

[0004] <Patent Documents>

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-101053 Summary of the invention

[0006] <Problems to be Solved by the Invention>

[0007] The present invention provides a technology capable of improving the responsiveness of flow rate control of a supercritical fluid.

[0008] <Methods used to solve the problem>

[0009] A substrate processing device according to one embodiment of the present invention comprises: a processing container having a processing space capable of accommodating a substrate whose surface is wetted by a liquid; and a processing fluid supply unit, which supplies a processing fluid in a supercritical state to the processing container, the processing fluid supply unit comprising: a fluid supply line, one side of which is connected to a fluid supply source, and the other side of which is connected to the processing container; a pump, which is arranged in the fluid supply line; a heating unit, which is arranged in the fluid supply line and is arranged on the downstream side of the pump, and heats the processing fluid to generate the processing fluid in a supercritical state; a first flow adjustment unit, which is arranged in the fluid supply line and is arranged between the pump and the heating unit, and is arranged to adjust the supply flow rate of the processing fluid supplied to the processing container; a first pressure measuring unit, which is arranged in the fluid supply line and is arranged on the downstream side of the first pressure measuring unit A flow regulating unit is provided between the heating unit to measure the pressure of the treatment fluid; a second pressure measuring unit is provided in the fluid supply pipeline and between the pump and the first flow regulating unit to measure the pressure of the treatment fluid; a branch point is provided between the pump and the first flow regulating unit in the fluid supply pipeline; a connection point is provided on the upstream side of the pump in the fluid supply pipeline; a branch pipeline connects the branch point with the connection point; a second flow regulating unit is provided in the branch pipeline to adjust the supply flow rate of the treatment fluid supplied to the treatment container; and a control unit controls the second flow regulating unit based on the first pressure of the treatment fluid in a liquid state measured by the first pressure measuring unit and the second pressure of the treatment fluid in a liquid state measured by the second pressure measuring unit.

[0010] <Effects of the Invention>

[0011] According to the present invention, the responsiveness of the flow rate control of the supercritical fluid can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a diagram showing a configuration example of a substrate processing apparatus according to an embodiment.

[0013] Figure 2 It is a diagram showing a configuration example of a liquid processing unit.

[0014] Figure 3 It is a schematic perspective view showing a structural example of a drying unit.

[0015] Figure 4 It is a diagram showing a configuration example of a drying unit.

[0016] Figure 5 It is a diagram showing a configuration example of a supply unit.

[0017] Figure 6It is a diagram showing a configuration example of the third flow rate adjustment unit and its periphery.

[0018] Figure 7 FIG. 1 is a diagram showing a substrate processing method according to an embodiment.

[0019] Figure 8 FIG. 2 is a diagram showing a substrate processing method according to an embodiment.

[0020] Fig. 9 FIG. 3 is a diagram showing a substrate processing method according to an embodiment.

[0021] Fig.10 FIG. 4 is a diagram showing a substrate processing method according to an embodiment.

[0022] Fig.11 FIG. 5 is a diagram showing a substrate processing method according to an embodiment.

[0023] Fig.12 FIG. 6 is a diagram showing a substrate processing method according to an embodiment.

[0024] Fig.13 FIG. 7 is a diagram showing a substrate processing method according to an embodiment.

[0025] Fig.14 FIG. 8 is a diagram showing a substrate processing method according to an embodiment. DETAILED DESCRIPTION

[0026] Hereinafter, non-limiting exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In all the drawings, the same or corresponding components or parts are denoted by the same or corresponding reference numerals, and repeated descriptions are omitted.

[0027] [Structure of substrate processing apparatus]

[0028] Reference Figure 1 , the structure of the substrate processing apparatus 1 according to the embodiment will be described. Figure 1 1 is a diagram showing a configuration example of a substrate processing apparatus 1 according to an embodiment. In order to clarify the positional relationship, the X-axis, Y-axis, and Z-axis are defined to be orthogonal to each other, and the positive direction of the Z-axis is defined as the vertical upward direction.

[0029] like Figure 1 As shown, the substrate processing apparatus 1 includes a loading / unloading station 2, a processing station 3, and a control device 6. The loading / unloading station 2 and the processing station 3 are provided adjacent to each other.

[0030] The loading / unloading station 2 includes a carrier placement unit 11 and a conveying unit 12. The carrier C is placed on the carrier placement unit 11. The carrier C accommodates a plurality of substrates in a horizontal state. The substrate is, for example, a semiconductor wafer (hereinafter referred to as a "wafer W").

[0031] The conveying section 12 is provided adjacent to the carrier placement section 11. Inside the conveying section 12, a conveying device 13 and a delivery section 14 are arranged.

[0032] The transport device 13 includes a wafer holding mechanism for holding the wafer W. The transport device 13 can move horizontally, vertically, and rotate about a vertical axis. The transport device 13 transports the wafer W between the carrier C and the delivery unit 14 using the wafer holding mechanism.

[0033] The processing station 3 is provided adjacent to the conveying unit 12. The processing station 3 includes a conveying block 4, a plurality of processing blocks 5, and a plurality of supply units 19.

[0034] The transport block 4 includes a transport area 15 and a transport device 16. The transport area 15 is, for example, a rectangular parallelepiped area extending along the arrangement direction (X-axis direction) of the loading / unloading stations 2 and the processing stations 3. The transport device 16 is disposed in the transport area 15.

[0035] The transport device 16 includes a wafer holding mechanism for holding the wafer W. The transport device 16 can move horizontally, vertically, and rotate about a vertical axis. The transport device 16 transports the wafer W between the interface 14 and the plurality of processing blocks 5 using the wafer holding mechanism.

[0036] The plurality of processing blocks 5 are arranged adjacent to the conveying area 15 on both sides of the conveying area 15. Specifically, the plurality of processing blocks 5 are arranged on one side (positive Y-axis side) and the other side (negative Y-axis side) of the conveying area 15 in a direction (Y-axis direction) orthogonal to the arrangement direction (X-axis direction) of the loading and unloading stations 2 and the processing stations 3.

[0037] Although not shown, the plurality of processing blocks 5 are arranged in multiple layers (e.g., three layers) along the vertical direction. The wafer W is transported between the processing blocks 5 arranged in each layer and the interface 14 by a transport device 16 arranged in the transport block 4. The number of layers of the plurality of processing blocks 5 is not limited to three layers.

[0038] Each processing block 5 includes a liquid processing unit 17 and a drying unit 18 .

[0039] The liquid processing unit 17 performs a cleaning process for cleaning the pattern forming surface, ie, the upper surface of the wafer W. The liquid processing unit 17 performs a liquid film forming process for forming a liquid film on the upper surface of the cleaned wafer W. The structure of the liquid processing unit 17 will be described later.

[0040] The drying unit 18 performs supercritical drying on the wafer W after the liquid film forming process. Specifically, the drying unit 18 dries the wafer W by bringing the wafer W after the liquid film forming process into contact with a processing fluid in a supercritical state (hereinafter also referred to as "supercritical fluid"). The structure of the drying unit 18 will be described later.

[0041] The liquid processing unit 17 and the drying unit 18 are arranged along the conveying area 15 (along the X-axis direction). The liquid processing unit 17 is arranged on the side closer to the loading / unloading station 2 than the drying unit 18.

[0042] Each processing block 5 includes one liquid processing unit 17 and one drying unit 18. The substrate processing apparatus 1 is provided with the same number of liquid processing units 17 and drying units 18.

[0043] The drying unit 18 includes a processing area 181 and a delivery area 182. Supercritical drying is performed in the processing area 181. In the delivery area 182, wafers W are delivered between the conveyance block 4 and the processing area 181. The processing area 181 and the delivery area 182 are arranged along the conveyance area 15.

[0044] The delivery region 182 is arranged on the side closer to the liquid processing unit 17 than the processing region 181. In each processing block 5, the liquid processing unit 17, the delivery region 182, and the processing region 181 are arranged in this order along the transport region 15.

[0045] One supply unit 19 is arranged for three processing blocks 5. For example, one supply unit 19 is arranged for three processing blocks 5 stacked in the vertical direction.

[0046] The supply unit 19 supplies the processing fluid to the drying unit 18. Specifically, the supply unit 19 includes a supply equipment group including a flow meter, a flow regulator, a back pressure valve, a heater, etc., and a box for accommodating the supply equipment group. In this embodiment, the supply unit 19 supplies carbon dioxide (CO 2 ) as the processing fluid. The structure of the supply unit 19 will be described later. The processing fluid can be supplied from one supply unit 19 to the three processing blocks 5.

[0047] The control device 6 is, for example, a computer, and includes a control unit 7 and a storage unit 8. The control unit 7 includes a microcomputer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input / output port, and various circuits. The CPU of the microcomputer reads and executes a program stored in the ROM to control the conveying devices 13 and 16, the liquid processing unit 17, the drying unit 18, and the supply unit 19.

[0048] The program may be stored in a computer-readable storage medium and installed from the storage medium into the storage unit 8 of the control device 6. Examples of computer-readable storage media include a hard disk (HD), a floppy disk (FD), a compact disk (CD), a magneto-optical disk (MO), and a memory card.

[0049] The storage unit 8 is realized by, for example, a semiconductor memory element such as a RAM or a flash memory, or a storage device such as a hard disk or an optical disk.

[0050] In the substrate processing apparatus 1 configured as described above, first, the conveyor device 13 of the loading / unloading station 2 takes out the wafer W from the carrier C placed on the carrier placement portion 11, and places the taken-out wafer W on the delivery portion 14. The wafer W placed on the delivery portion 14 is taken out from the delivery portion 14 by the conveyor device 16 of the processing station 3, and is carried into the liquid processing unit 17.

[0051] Wafer W carried into liquid processing unit 17 is subjected to cleaning and liquid film formation by liquid processing unit 17 and then carried out of liquid processing unit 17 by conveyor device 16. Wafer W carried out of liquid processing unit 17 is carried into drying unit 18 by conveyor device 16 and subjected to drying by drying unit 18.

[0052] Wafers W dried by drying unit 18 are carried out by conveyor 16 and placed on interface 14. Wafers W placed on interface 14 after processing are returned to carriers C of carrier placement unit 11 by conveyor 13.

[0053] [Structure of liquid processing unit]

[0054] Reference Figure 2 The structure of the liquid processing unit 17 will be described. Figure 2 2 is a diagram showing a configuration example of the liquid processing unit 17. The liquid processing unit 17 is configured as, for example, a single-wafer cleaning device that cleans each wafer W by spin cleaning.

[0055] like Figure 2As shown, liquid processing unit 17 holds wafer W substantially horizontally using wafer holding mechanism 25 disposed in outer chamber 23 forming a processing space, and rotates wafer W by rotating wafer holding mechanism 25 about a vertical axis.

[0056] The liquid processing unit 17 moves the nozzle arm 26 over the rotating wafer W and supplies chemical liquid and rinse liquid in a predetermined order from the chemical liquid nozzle 26 a provided at the front end of the nozzle arm 26 , thereby performing a cleaning process on the upper surface of the wafer W.

[0057] In the liquid processing unit 17, a chemical liquid supply path 25a is also formed inside the wafer holding mechanism 25. The lower surface of the wafer W is also cleaned by the chemical liquid or the rinse liquid supplied from the chemical liquid supply path 25a.

[0058] The cleaning process first removes particles and organic contaminants using, for example, SC1 solution (a mixture of ammonia and hydrogen peroxide solution) as an alkaline chemical solution, and then rinses with deionized water (hereinafter referred to as "DIW") as a rinse solution.

[0059] Next, the natural oxide film is removed using a diluted hydrofluoric acid aqueous solution (hereinafter referred to as "DHF") as an acidic chemical solution, and then rinsed and cleaned using DIW.

[0060] The various liquid medicines are received by the outer chamber 23 and the inner cup 24 disposed in the outer chamber 23, and are discharged from the drain port 23a provided at the bottom of the outer chamber 23 and the drain port 24a provided at the bottom of the inner cup 24. The atmosphere in the outer chamber 23 is discharged from the exhaust port 23b provided at the bottom of the outer chamber 23.

[0061] The liquid film formation process is performed after the rinsing process in the cleaning process. Specifically, the liquid processing unit 17 rotates the wafer holding mechanism 25 while supplying liquid IPA (IsoPropyl Alcohol) (hereinafter also referred to as "IPA liquid") to the upper and lower surfaces of the wafer W. As a result, the DIW remaining on both sides of the wafer W is replaced with IPA. After that, the liquid processing unit 17 slowly stops the rotation of the wafer holding mechanism 25.

[0062] The wafer W that has completed the liquid film forming process is delivered to the conveying device 16 by a delivery mechanism (not shown) provided in the wafer holding mechanism 25 with a liquid film of IPA liquid formed on its upper surface (the surface is wetted with IPA liquid) and is unloaded from the liquid processing unit 17 .

[0063] The liquid film formed on the wafer W prevents pattern collapse caused by evaporation (gasification) of the liquid on the upper surface of the wafer W during the conveyance of the wafer W from the liquid processing unit 17 to the drying unit 18 or during the loading operation into the drying unit 18 .

[0064] 〔Structure of drying unit〕

[0065] Reference Figure 3 and Figure 4 , the structure of the drying unit 18 is described. Figure 3 It is a schematic perspective view showing a structural example of the drying unit 18 . Figure 4 1 is a diagram showing a configuration example of the drying unit 18 .

[0066] like Figure 3 As shown, the drying unit 18 includes a main body 31, a holding plate 32, and a cover member 33. The box-shaped main body 31 is formed with an opening 34 for carrying in and out the wafer W. The holding plate 32 holds the wafer W to be processed in the horizontal direction. The cover member 33 supports the holding plate 32. When the wafer W is carried into the main body 31, the cover member 33 closes the opening 34. The main body 31 is an example of a processing container.

[0067] The main body 31 is a container having a processing space formed therein that can accommodate, for example, a 300 mm diameter wafer W. Supply ports 35, 36 and an exhaust port 37 are provided on the wall of the main body 31. The supply ports 35, 36 and the exhaust port 37 are respectively connected to a supply flow path and an exhaust flow path for circulating the supercritical fluid in the drying unit 18.

[0068] The supply port 35 is connected to the side surface of the box-shaped main body 31 opposite to the opening 34. The supply port 36 is connected to the bottom surface of the main body 31. The discharge port 37 is connected to the lower side of the opening 34. Figure 3 Although two supply ports 35 and 36 and one discharge port 37 are shown in the figure, the numbers of the supply ports 35 and 36 and the discharge port 37 are not particularly limited.

[0069] A fluid supply head 38, a fluid supply head 39, and a fluid discharge head 40 are provided inside the main body 31. The fluid supply heads 38 and 39 have a plurality of supply ports arranged along the length direction of the fluid supply heads 38 and 39. The fluid discharge head 40 has a plurality of discharge ports arranged along the length direction of the fluid discharge head 40.

[0070] The fluid supply head 38 is connected to the supply port 35. The fluid supply head 38 is provided inside the box-shaped main body 31 adjacent to the side surface opposite to the opening 34. A plurality of supply ports arranged in the fluid supply head 38 face the opening 34 side.

[0071] The fluid supply head 39 is connected to the supply port 36. The fluid supply head 39 is provided at the center of the bottom surface inside the box-shaped main body 31. A plurality of supply ports arranged in the fluid supply head 39 face upward.

[0072] The fluid discharge head 40 is connected to the discharge port 37. The fluid discharge head 40 is adjacent to the side surface of the opening 34 in the box-shaped main body 31 and is provided below the opening 34. A plurality of discharge ports arranged in the fluid discharge head 40 face upward.

[0073] The fluid supply heads 38 and 39 supply the supercritical fluid into the main body 31. The fluid discharge head 40 guides and discharges the supercritical fluid in the main body 31 to the outside of the main body 31. The supercritical fluid discharged to the outside of the main body 31 via the fluid discharge head 40 includes the IPA liquid dissolved in the supercritical fluid in the supercritical state from the surface of the wafer W.

[0074] like Figure 4 As shown, the second supply line 72 of the supply unit 19 is connected to the drying unit 18. The second supply line 72 is branched into two supply lines in the drying unit 18 (in Figure 4 One end is connected to the supply port 35, and the other end is connected to the supply port 36 (in Figure 4 In the second supply line 72, a first flow rate adjustment unit 250, a pressure sensor 243, and a heater 68 are provided in order from the upstream side (supply unit 19 side).

[0075] The first flow rate adjustment unit 250 adjusts the supply flow rate of the treatment fluid supplied to the main body 31. The first flow rate adjustment unit 250 includes valves 211-213 and throttles 221-223.

[0076] The valves 211, 212 and 213 are connected in parallel with each other. The valves 211, 212 and 213 are valves for adjusting the opening (ON) and closing (OFF) of the flow of the treatment fluid. The valves 211, 212 and 213 allow the treatment fluid to flow into the throttling members 221, 222 and 223 in the open state, and do not allow the treatment fluid to flow into the throttling members 221, 222 and 223 in the closed state. The valves 211, 212 and 213 are examples of first on-off valves.

[0077] The throttles 221, 222, and 223 are connected in series with the valves 211, 212, and 213, respectively. The throttles 221, 222, and 223 play a role in reducing the flow rate and adjusting the pressure of the gaseous or liquid treatment fluid supplied from the supply unit 19 through the valves 211, 212, and 213, respectively. The throttles 221, 222, and 223 can allow the pressure-adjusted treatment fluid to flow through the second supply line 72 on the downstream side. The throttles 221, 222, and 223 are an example of a first throttle unit.

[0078] The pressure sensor 243 measures the pressure of the treatment fluid flowing in the second supply line 72 between the first flow rate adjustment unit 250 and the heater 68. That is, the pressure sensor 243 can measure the pressure on the secondary side of the throttles 221, 222, and 223. The output of the pressure sensor 243 is sent to the control unit 7. The pressure sensor 243 is an example of a first pressure measuring unit.

[0079] The heater 68 is, for example, a spiral heater. The heater 68 is wound around the second supply line 72, and heats the gaseous or liquid processing fluid flowing in the second supply line 72 to generate a supercritical processing fluid. The heater 68 is an example of a heating unit.

[0080] The discharge line 76 is connected to the discharge port 37. In the discharge line 76, a pressure sensor 242, a valve 214, a flow meter 251, and a back pressure valve 231 are provided in order from the upstream side, that is, the main body 31 side. The discharge line 76, the pressure sensor 242, the valve 214, the flow meter 251, and the back pressure valve 231 constitute a part of the discharge unit.

[0081] The pressure sensor 242 measures the pressure of the treatment fluid flowing in the discharge line 76 immediately after the main body 31. That is, the pressure sensor 242 can measure the pressure of the treatment fluid in the main body 31. The output of the pressure sensor 242 is sent to the control unit 7. The pressure sensor 242 is an example of a third pressure measuring unit.

[0082] The valve 214 is a valve for adjusting the opening and closing of the flow of the treatment fluid. In the open state, the treatment fluid flows to the discharge pipeline 76 on the downstream side, and in the closed state, the treatment fluid does not flow to the discharge pipeline 76 on the downstream side.

[0083] The flow meter 251 measures the discharge flow rate of the treatment fluid flowing through the discharge line 76. The output of the flow meter 251 is sent to the control unit 7.

[0084] The back pressure valve 231 adjusts the valve opening to allow the fluid to flow to the secondary side when the pressure on the primary side of the discharge line 76 exceeds the set pressure, thereby maintaining the pressure on the primary side at the set pressure. For example, the set pressure of the back pressure valve 231 is adjusted by the control unit 7 based on the output of the pressure sensor 242. The back pressure valve 231 is an example of a pressure regulating unit.

[0085] A temperature sensor 241 is provided to detect the temperature of the treatment fluid in the main body 31. The output of the temperature sensor 241 is sent to the control unit 7.

[0086] In the drying unit 18, the IPA liquid between the patterns formed on the wafer W gradually dissolves in the supercritical fluid by contacting with the supercritical fluid in a high pressure state (eg, 16 MPa), and the space between the patterns is gradually replaced by the supercritical fluid. Thus, the space between the patterns is finally filled only with the supercritical fluid.

[0087] After the IPA liquid is removed from between the patterns, the pressure inside the body 31 is reduced from the high pressure state to the atmospheric pressure, thereby 2 The supercritical state changes to the gas state, and the space between the patterns is occupied only by the gas. In this way, the IPA liquid between the patterns is removed, and the drying process of the wafer W is completed.

[0088] The supercritical fluid has a lower viscosity than a liquid (e.g., IPA liquid) and a higher ability to dissolve liquids. In addition, there is no interface between the supercritical fluid and the liquid or gas in equilibrium. Thus, in a drying process using a supercritical fluid, the liquid can be dried without being affected by surface tension. Therefore, according to an embodiment, pattern collapse during the drying process can be suppressed.

[0089] In the embodiment, IPA liquid is used as the liquid for preventing drying, and supercritical CO is used. 2 As an example of the treatment fluid, liquids other than IPA may be used as the liquid for preventing drying, and supercritical CO may be used. 2 Fluid other than the above is used as the processing fluid.

[0090] 〔Structure of supply unit〕

[0091] Reference Figure 5 , the structure of the supply unit 19 is described. Figure 5 1 is a diagram showing a configuration example of the supply unit 19 . Figure 5 The supply unit 19 shown in the figure supplies the process fluid to the three drying units 18A, 18B and 18C. Figure 4 Corresponding to the drying unit 18 in.

[0092] The supply unit 19 includes a first supply line 71 connected to a treatment fluid supply source 90 and a plurality of second supply lines 72A, 72B, and 72C connected to the first supply line 71. The second supply lines 72A, 72B, and 72C are connected to the first supply line 71 at a plurality of branch points 77A and 77B provided on the first supply line 71. Specifically, the second supply line 72A is connected to the first supply line 71 at the branch point 77A, and the second supply lines 72B and 72C are connected to the first supply line 71 at the branch point 77B. The second supply lines 72A to 72C correspond to Figure 4 The second supply line 72 in the embodiment of the present invention is connected to the drying unit 18A, the second supply line 72B is connected to the drying unit 18B, and the second supply line 72C is connected to the drying unit 18C. The processing fluid supply source 90 is an example of a fluid supply source, and the first supply line 71 and the second supply lines 72A to 72C constitute a part of the fluid supply line.

[0093] The first supply line 71 is provided with a connection point 61. The first supply line 71 is provided with a filter 64, a condenser 65, a tank 66, and a pump 67 in order from the upstream side (the side of the treatment fluid supply source 90). The connection point 61 is provided upstream of the filter 64.

[0094] The filter 64 filters the gaseous processing fluid flowing in the first supply line 71 to remove foreign matter contained in the processing fluid. By removing foreign matter in the processing fluid using the filter 64, it is possible to suppress the generation of particles on the surface of the wafer W during the drying process of the wafer W using the supercritical fluid.

[0095] The condenser 65 is connected to a cooling water supply unit (not shown) to exchange heat between the cooling water and the gaseous treatment fluid. Thus, the condenser 65 cools the gaseous treatment fluid flowing in the first supply line 71 to generate a liquid treatment fluid. The condenser 65 is an example of a cooling unit.

[0096] The tank 66 stores the liquid-state treatment fluid generated by the condenser 65. The pump 67 sends the liquid-state treatment fluid stored in the tank 66 to the downstream side of the first supply line 71.

[0097] A branch point 62A is provided on the second supply line 72A, a branch point 62B is provided on the second supply line 72B, and a branch point 62C is provided on the second supply line 72C. The branch point 62A is provided between the valve 115A and the drying unit 18A, the branch point 62B is provided between the valve 115B and the drying unit 18B, and the branch point 62C is provided between the valve 115C and the drying unit 18C. The supply unit 19 has a first branch line 73A connected to the branch point 62A, a first branch line 73B connected to the branch point 62B, and a first branch line 73C connected to the branch point 62C.

[0098] In the first branch line 73A, a valve 116A, a back pressure valve 131A, and a valve 114A are provided in order from the upstream side (branch point 62A side). In the first branch line 73B, a valve 116B, a back pressure valve 131B, and a valve 114B are provided in order from the upstream side (branch point 62B side). In the first branch line 73C, a valve 116C, a back pressure valve 131C, and a valve 114C are provided in order from the upstream side (branch point 62C side).

[0099] The valve 116A is a valve for adjusting the opening and closing of the flow of the treatment fluid. In the open state, the treatment fluid flows in the first branch pipeline 73A on the downstream side, and in the closed state, the treatment fluid does not flow in the first branch pipeline 73A on the downstream side. Valves 116B and 116C have the same structure as valve 116A.

[0100] The back pressure valve 131A adjusts the valve opening when the pressure on the primary side of the first branch line 73A exceeds the set pressure to allow the fluid to flow to the secondary side, thereby maintaining the pressure on the primary side at the set pressure. For example, the set pressure of the back pressure valve 131A is adjusted by the control unit 7 based on the output of the pressure sensor 142A and the pressure sensor 243. The back pressure valves 131B and 131C have the same structure as the back pressure valve 131A. The back pressure valves 131A to 131C are an example of a second flow rate adjustment unit.

[0101] The valve 114A is a valve for adjusting the opening and closing of the flow of the treatment fluid. In the open state, the treatment fluid flows in the first branch pipeline 73A on the downstream side, and in the closed state, the treatment fluid does not flow in the first branch pipeline 73A on the downstream side. Valves 114B and 114C have the same structure as valve 114A.

[0102] The supply unit 19 has a second branch line 74 connected to the first branch lines 73A to 73C. The first branch lines 73A to 73C are connected to the second branch line 74 at a plurality of connection points 75A and 75B provided in the second branch line 74. Specifically, the first branch line 73A is connected to the second branch line 74 at the connection point 75A, and the first branch lines 73B and 73C are connected to the second branch line 74 at the connection point 75B. The second branch line 74 is connected to the connection point 61. That is, the second branch line 74 connects the first branch lines 73A to 73C to the connection point 61. In addition, the second branch line 74 may not be provided, and the first branch lines 73A to 73C may be directly connected to the first supply line 71 at respective independent connection points on the upstream side of the filter 64.

[0103] In the second supply line 72A, between the branch point 77A and the branch point 62A, a pressure sensor 141A, a third flow rate adjustment unit 150A, a pressure sensor 142A, and a valve 115A are provided in order from the upstream side (branch point 77A side). In the second supply line 72B, between the branch point 77B and the branch point 62B, a pressure sensor 141B, a third flow rate adjustment unit 150B, a pressure sensor 142B, and a valve 115B are provided in order from the upstream side (branch point 77B side). In the second supply line 72C, between the branch point 77B and the branch point 62C, a pressure sensor 141C, a third flow rate adjustment unit 150C, a pressure sensor 142C, and a valve 115C are provided in order from the upstream side (branch point 77B side).

[0104] The pressure sensor 141A measures the pressure of the treatment fluid flowing in the second supply line 72A upstream of the third flow rate adjustment unit 150A. The output of the pressure sensor 141A is sent to the control unit 7. The pressure sensors 141B and 141C have the same structure as the pressure sensor 141A.

[0105] The third flow rate regulator 150A regulates the flow rate of the process fluid flowing in the first branch line 73 A. The third flow rate regulators 150B and 150C have the same structure as the third flow rate regulator 150A.

[0106] The pressure sensor 142A measures the pressure of the process fluid flowing in the second supply line 72A between the third flow rate adjustment unit 150A and the valve 115A. That is, the pressure sensor 142A can measure the pressure on the primary side of the throttles 221, 222, and 223. The pressure sensors 142B and 142C have the same structure as the pressure sensor 142A. The pressure sensors 142A to 142C are an example of a second pressure measuring unit.

[0107] The valve 115A is a valve for adjusting the opening and closing of the flow of the treatment fluid. In the open state, the treatment fluid flows to the second supply pipeline 72A on the downstream side, and in the closed state, the treatment fluid does not flow to the second supply pipeline 72A on the downstream side. Valves 115B and 115C have the same structure as valve 115A.

[0108] Reference Figure 6 , the structure of the third flow adjustment unit 150A is described. Figure 6 150A and its surroundings. The third flow rate adjustment units 150B and 150C have the same structure as the third flow rate adjustment unit 150A.

[0109] like Figure 6 As shown, the third flow rate adjustment unit 150A includes throttles 120 to 123 and valves 111 to 113. The throttles 121, 122 and 123 are connected in parallel to the throttle 120. The valve 111 is connected in series to the throttle 121. The valve 112 is connected in series to the throttle 122. The valve 113 is connected in series to the throttle 123.

[0110] The throttles 120 to 123 play a role in reducing the flow rate of the treatment fluid flowing in the second supply line 72A and adjusting the pressure. The throttles 120 to 123 can allow the treatment fluid of the adjusted pressure to flow through the second supply line 72A on the downstream side.

[0111] Valves 111 to 113 are valves for adjusting the opening and closing of the flow of the treatment fluid. In the open state, the treatment fluid flows to the second supply pipeline 72A on the downstream side, and in the closed state, the treatment fluid does not flow to the second supply pipeline 72A on the downstream side.

[0112] The basic operation of the supply unit 19 is described. The gaseous treatment fluid supplied from the treatment fluid supply source 90 to the first supply pipeline 71 is supplied to the condenser 65 via the filter 64, and is cooled and liquefied by the condenser 65. The liquefied treatment fluid is stored in the tank 66. The liquid treatment fluid stored in the tank 66 becomes a high-pressure fluid through the pump 67, and a part of it is supplied to the drying units 18A~18C. The high-pressure fluid supplied to the drying units 18A~18C becomes a supercritical state through the heater 68 and is used for drying. Another part of the high-pressure fluid flows to the first branch pipelines 73A~73C, and returns to the first supply pipeline 71 from the connection point 61. In this way, the treatment fluid circulates in the supply unit 19.

[0113] [Substrate processing method]

[0114] Reference Figure 7 to Figure 14Next, a substrate processing method according to the embodiment will be described. Next, a drying method (substrate processing method) performed using the drying unit 18A will be described. Figure 7 to Figure 14 is a diagram showing a substrate processing method according to an embodiment. Figure 7 to Figure 14 In FIG. 1 , as an example, the specific operation of the supply unit 19 when supplying the processing fluid to the drying unit 18A is shown. Figure 7 to Figure 14 During the operation shown, pump 67 continues to operate. Figure 7 to Figure 14 As shown, the processing fluid supply unit 80 includes the supply unit 19, the first flow rate adjustment unit 250 in the drying unit 18A, the pressure sensor 243, and the heater 68. The processing fluid supply unit 80 may also include the control device 6. The processing fluid supply unit 80 is an example of a fluid supply system.

[0115] <Wait time>

[0116] The standby process is a process in which the wafer W is transported to the drying unit 18A and waits for the supply of the processing fluid. Figure 7 As shown, valves 111 to 113 are in an open state. In addition, valves 114A, 115A and 116A are in an open state, and valves 211 to 214 are in a closed state. The process fluid guided to the second supply pipeline 72A passes through the throttle 120, and reaches the branch point 62A via the throttles 121 to 123, and flows to the first branch pipeline 73A. The process fluid guided to the first branch pipeline 73A reaches the connection point 61 via the valve 116A, the back pressure valve 131A, the valve 114A and the second branch pipeline 74, and then returns to the tank 66 via the filter 64 and the condenser 65.

[0117] During this series of actions, the control unit 7 receives the output from the pressure sensor 142A and adjusts the set pressure of the back pressure valve 131A so that the pressure of the treatment fluid flowing downstream of the throttle 120 of the second supply line 72A becomes a preset pressure (e.g., 19.0 MPa). That is, the control unit 7 changes the amount of the treatment fluid flowing in the first branch line 73A to control the pressure of the treatment fluid at the branch point 62A.

[0118] In the standby process, the process fluid is not supplied from the process fluid supply source 90, and the process fluid circulates in the supply unit 19. At this time, since the valves 111 to 113 are open, the process fluid is unlikely to accumulate in the third flow rate adjustment section 150A, thereby suppressing the generation of particles associated with accumulation.

[0119] <Voltage Boosting Process>

[0120] After the standby treatment, a pressure boosting treatment is performed. The pressure boosting treatment is a treatment for raising the pressure in the main body 31 to the treatment pressure. In the pressure boosting treatment, first, the pressure is boosted by supplying a treatment fluid in a supercritical state at a first flow rate into the main body 31. Thereafter, the pressure is further boosted by supplying a treatment fluid in a supercritical state to the main body 31 at a second flow rate higher than the first flow rate. Thereafter, the pressure is further boosted by supplying a treatment fluid in a supercritical state to the main body 31 at a third flow rate higher than the second flow rate. That is, three stages of pressure boosting are performed.

[0121] In the pressure increase at the first flow rate, as Figure 8 As shown, valves 111 to 113 are closed, and valves 114A, 115A, and 116A are opened. The process fluid introduced into the second supply line 72A reaches the branch point 62A via one throttle 120 instead of three throttles 121 to 123 .

[0122] A portion of the treated fluid reaching the branch point 62A is supplied to the drying unit 18A, and another portion flows from the branch point 62A to the first branch line 73A. The treated fluid guided to the first branch line 73A reaches the connection point 61 via the valve 116A, the back pressure valve 131A, the valve 114A, and the second branch line 74, and then returns to the tank 66 via the filter 64 and the condenser 65.

[0123] During this series of actions, the control unit 7 receives the output from the pressure sensor 142A and adjusts the set pressure of the back pressure valve 131A so that the pressure of the treatment fluid flowing downstream of the throttle 120 of the second supply line 72A becomes a preset pressure (e.g., 7.0 MPa). That is, the control unit 7 changes the amount of the treatment fluid flowing in the first branch line 73A to control the pressure of the treatment fluid at the branch point 62A.

[0124] In the drying unit 18A, the valve 211 is in an open state, and the valves 212, 213 and 214 are in a closed state. Therefore, the processing fluid supplied to the drying unit 18 reaches the heater 68 via the throttling member 221 instead of the throttling members 222 and 223, and is heated by the heater 68 to become a supercritical state. Then, the processing fluid in the supercritical state is supplied to the main body 31 at a first flow rate. The pressure in the main body 31 supplied with the processing fluid in the supercritical state gradually rises from 0 MPa. In the pressure increase at the first flow rate, the pressure of the processing fluid at the branch point 62A is maintained at a predetermined pressure, so the supply pressure of the processing fluid in the supercritical state to the main body 31 is constant.

[0125] During the pressure increase at the first flow rate, the control unit 7 receives the output from the pressure sensor 242, and when the pressure in the main body 31 reaches a preset pressure, the pressure is transferred to the pressure increase at the second flow rate. The preset pressure may be 3.0 MPa or less, for example, 1.0 MPa. Instead of using the pressure value as a reference, the pressure may be transferred to the pressure increase at the second flow rate when a preset time has passed since the pressure increase at the first flow rate was started.

[0126] In the pressure increase at the second flow rate, first, as Fig. 9 As shown, valve 212 is in the open state. The states of other valves are the same as Figure 8 As a result, the processing fluid supplied to the drying unit 18A reaches the heater 68 not only through the throttle 221 but also through the throttle 222, and is heated by the heater 68 to become a supercritical state. Therefore, the flow rate of the processing fluid in the supercritical state supplied to the main body 31 rises to the second flow rate.

[0127] During this series of actions, the control unit 7 receives the output from the pressure sensor 242 and adjusts the set pressure of the back pressure valve 131A so that the pressure in the main body 31 gradually increases at a predetermined change. That is, the control unit 7 changes the amount of the treatment fluid flowing in the first branch pipeline 73A to control the pressure of the treatment fluid at the branch point 62A. Since the pressure of the treatment fluid at the branch point 62A gradually increases, the supply pressure of the treatment fluid in the supercritical state to the main body 31 also gradually increases. When the pressure in the main body 31 reaches the preset pressure, the control unit 7 switches to a pressure increase at a third flow rate. The preset pressure can be less than 7.0 MPa, for example, 7.0 MPa. It is also possible not to use the pressure value as a reference, but to transfer to a pressure increase at a third flow rate when a preset time has passed since the start of the pressure increase at the second flow rate.

[0128] In the pressure increase at the third flow rate, first, as Fig.10 As shown, valve 213 is in the open state. The states of other valves are the same as Fig. 9 As a result, the process fluid supplied to the drying unit 18A reaches the heater 68 via the throttles 221, 222 and 223, and is heated by the heater 68 to become a supercritical state. Therefore, the flow rate of the process fluid in a supercritical state supplied to the main body 31 increases to the third flow rate.

[0129] During this series of actions, the control unit 7 receives the output from the pressure sensor 242 and adjusts the set pressure of the back pressure valve 131A so that the pressure in the main body 31 gradually increases with a predetermined change. That is, the control unit 7 changes the amount of the treatment fluid flowing in the first branch line 73A to control the pressure of the treatment fluid at the branch point 62A. Since the pressure of the treatment fluid at the branch point 62A gradually increases, the supply pressure of the treatment fluid in the supercritical state to the main body 31 also gradually increases.

[0130] During the pressure increase at the third flow rate, as the pressure of the process fluid at the branch point 62A increases, the differential pressure between the upstream side and the downstream side of the throttling member 120 decreases. Therefore, when the pressure of the process fluid at the branch point 62A reaches a preset pressure (e.g., 11.0 MPa), Fig.11 As shown, the control unit 7 opens the valve 111. The states of the other valves are the same as Fig.10 As a result, even if the differential pressure between the upstream and downstream sides of the throttle 120 decreases, the treated fluid can continue to flow through the first branch line 73A and the second branch line 74. During this period, the pressure in the main body 31 rises from 7.0 MPa to 13.0 MPa, for example.

[0131] When the pressure of the process fluid at the branch point 62A reaches a higher preset pressure (e.g., 14.5 MPa), Fig.12 As shown, the control unit 7 also opens the valve 112. The states of the other valves are the same as Fig.11 As a result, even if the differential pressure between the upstream and downstream sides of the throttle 120 further decreases, the treated fluid can continue to flow through the first branch line 73A and the second branch line 74. During this period, the pressure in the main body 31 rises from 13.0 MPa to 15.0 MPa, for example.

[0132] When the pressure of the process fluid at the branch point 62A reaches a higher preset pressure (e.g., 17.0 MPa), Fig.13 As shown, the control unit 7 also opens the valve 113. The states of the other valves are the same as Fig.12 As a result, even if the differential pressure between the upstream and downstream sides of the throttle 120 further decreases, the treated fluid can continue to flow through the first branch line 73A and the second branch line 74. During this period, the pressure in the main body 31 rises from 15.0 MPa to 16.0 MPa, for example.

[0133] The voltage boosting process is performed in this manner.

[0134] <Distribution Processing>

[0135] After the pressure-raising treatment, the flow treatment is performed. The flow treatment is a treatment process in which the IPA liquid film on the wafer W transported into the main body 31 is dried using a treatment fluid in a supercritical state. In the flow treatment, Fig.14 As shown, valves 111 to 113 are in an open state. In addition, valves 114A, 115A, and 116A are in an open state. The process fluid guided to the second supply line 72A reaches the branch point 62A via the four throttles 120 to 123.

[0136] A portion of the treated fluid reaching the branch point 62A is supplied to the drying unit 18A, and another portion flows from the branch point 62A to the first branch line 73A. The treated fluid guided to the first branch line 73A reaches the connection point 61 via the valve 116A, the back pressure valve 131A, the valve 114A, and the second branch line 74, and then returns to the tank 66 via the filter 64 and the condenser 65.

[0137] In addition, in the drying unit 18A, the valves 211 to 214 are in an open state. Therefore, the processing fluid flows through the second supply line 72A and is supplied from the supply port 35 to the body 31. In addition, the processing fluid flows through the discharge line 76 from the discharge port 37 of the body 31 and is discharged to the outside through the valve 214, the flow meter 251 and the back pressure valve 231.

[0138] During this series of actions, first, the control unit 7 receives the first pressure P1 of the treatment fluid in a liquid state measured by the pressure sensor 243 and the second pressure P2 of the treatment fluid in a liquid state measured by the pressure sensor 142A. Next, the control unit 7 calculates the supply flow rate of the treatment fluid flowing in the second supply line 72A based on the first pressure P1 and the second pressure P2. Next, the control unit 7 adjusts the set pressure of the back pressure valve 131A so that the calculated supply flow rate of the treatment fluid becomes the set flow rate during the circulation process.

[0139] The control unit 7 calculates the supply flow rate Q of the treatment fluid flowing in the second supply line 72 using, for example, the calculation formula of Formula (1).

[0140] Q=Cd·(ΔP) 1 / 2 ··· (1)

[0141] In the formula (1), ΔP is a value obtained by subtracting the first pressure P1 from the second pressure P2 (ΔP=P2-P1), and Cd is a flow coefficient.

[0142] The flow coefficient Cd can be calculated by, for example, the calculation formula (2) when the treatment fluid is allowed to flow through the main body 31 under given conditions and the first pressure P1, the second pressure P2, and the discharge flow rate of the treatment fluid measured by the flow meter 251 are stable.

[0143] Qs=Cd·(ΔPs) 1 / 2 ··· (2)

[0144] In formula (2), Qs is the discharge flow rate of the treatment fluid measured by the flow meter 251 at the time point when the first pressure P1, the second pressure P2 and the discharge flow rate of the treatment fluid measured by the flow meter 251 are stable. In formula (2), ΔPs is the pressure difference between the second pressure P2 and the first pressure P1 at the time point when the first pressure P1, the second pressure P2 and the discharge flow rate of the treatment fluid measured by the flow meter 251 are stable (ΔPs =

[0145] P2-P1).

[0146] The flow coefficient Cd can be calculated for each drying unit 18A to 18C. In this case, it is possible to obtain excellent uniformity of the supply flow rate between the plurality of drying units 18A to 18C. The flow coefficient Cd can also be calculated according to each state of the valves 211 to 213. The flow coefficient Cd can include a flow coefficient when one of the three valves 211 to 213 is in an open state, a flow coefficient when two of the three valves 211 to 213 are in an open state, and a flow coefficient when all the three valves 211 to 213 are in an open state.

[0147] Flow coefficient Cd when valve 211 is in the open state A The flow coefficient Cd is calculated by the calculation formula (2) when the valve 211 is open, the valves 212 and 213 are closed, and the treatment fluid is allowed to flow through the main body 31 under given conditions. B The flow coefficient Cd when the valve 213 is in the open state C and flow coefficient Cd A Calculate similarly.

[0148] Flow coefficient Cd when valves 211 and 212 are in the open state AB The flow coefficient Cd is calculated by the calculation formula (2) when the valves 211 and 212 are open, the valve 213 is closed, and the treatment fluid is allowed to flow through the main body 31 under given conditions. BC The flow coefficient Cd when valves 211 and 213 are open AC and flow coefficient Cd AB Calculate similarly.

[0149] Flow coefficient Cd when all valves 211 to 213 are open ABCThe flow coefficient Cd is calculated by the calculation formula (2) when the valves 211, 212, and 213 are opened and the treated fluid is allowed to flow through the body 31 under given conditions. ABC It can also be measured by the flow coefficient Cd A , Flow coefficient Cd B and flow coefficient Cd C The sum (Cd A +Cd B +Cd C ) to calculate.

[0150] During the flow process, the control unit 7 also receives the output from the pressure sensor 242 and adjusts the set pressure of the back pressure valve 231 so that the pressure in the main body 31 is maintained at the set pressure during the flow process.

[0151] <Discharge treatment>

[0152] After the circulation process, the discharge process is performed. The discharge process is a process of discharging the treated fluid from the main body 31. In the discharge process, valves 211, 212, and 213 are set to the closed state. The states of the other valves are the same as Fig.14 When the pressure in the main body 31 becomes lower than the critical pressure of the processing fluid due to the exhaust process, the processing fluid in the supercritical state vaporizes and escapes from the concave portion of the pattern. Thus, the drying process for one wafer W is completed.

[0153] When the processing fluid is supplied to the drying units 18B and 18C, the valves 111 to 113 and 211 to 213 and the like are controlled in the same manner as when the processing fluid is supplied to the drying unit 18A.

[0154] As described above, in the substrate processing apparatus 1, during the circulation process, first, the control unit 7 calculates the supply flow rate of the processing fluid flowing in the second supply line 72A based on the first pressure P1 measured by the pressure sensor 243 and the second pressure P2 measured by the pressure sensor 142A. Next, the control unit 7 adjusts the set pressure of the back pressure valve 231 so that the calculated supply flow rate of the processing fluid becomes the set flow rate during the circulation process. In this case, the back pressure valve 231 can be controlled based on the supply flow rate of the processing fluid in a liquid state flowing at a position upstream of the main body 31, so that the responsiveness of the flow rate control of the supercritical fluid can be improved. As a result, excellent uniformity of the supply flow rate can be obtained between the plurality of drying units 18A to 18C. In addition, excellent uniformity of the supply flow rate can be obtained between the plurality of processes performed by the specific drying units 18A to 18C. In addition, the flow meter for controlling the back pressure valve 231 may not be provided on the upstream side of the main body 31.

[0155] In contrast, consider the case where the set pressure of the back pressure valve 131A is adjusted in such a manner that the pressure measured by the pressure sensor 242 provided in the discharge pipeline 76 is maintained at the set pressure during the circulation treatment. The pressure sensor 242 measures the pressure of the treatment fluid downstream of the main body 31. The treatment fluid downstream of the main body 31 is in a supercritical state or a gas state and is compressible. In addition, the pressure sensor 242 is provided at a position farther away from the back pressure valve 131A than the pressure sensors 243 and 142A. Therefore, when the back pressure valve 131A is controlled based on the pressure measured by the pressure sensor 242, it is difficult to improve the responsiveness of the flow control of the supercritical fluid.

[0156] In the substrate processing apparatus 1, the pressure sensors 243 and 142A are provided upstream of the heater 68. Therefore, the supply flow rate of the liquid processing fluid can be reliably measured. As a result, the supply flow rate of the processing fluid to the main body 31 can be adjusted with high accuracy.

[0157] In addition, in the substrate processing apparatus 1, throttles 221 to 223 are provided at positions where the processing fluid in a liquid state flows. The density and viscosity of the processing fluid in a liquid state hardly change due to temperature changes or pressure changes, so it is easy to calculate the flow coefficient Cd. In contrast, the density and viscosity of the processing fluid in a supercritical state change according to temperature changes or pressure changes, so it is difficult to calculate the flow coefficient Cd.

[0158] Furthermore, in the substrate processing apparatus 1, in the standby process, the pressure-increasing process, the circulation process, and the discharge process, the processing fluid can always be circulated in the flow path passing through the first supply line 71, the second supply lines 72A to 72C, the first branch lines 73A to 73C, and the second branch line 74. Therefore, the difference between processes in the temperature of the processing fluid supplied to the main body 31 in the pressure-increasing process, the circulation process, and the discharge process can be reduced.

[0159] In addition, in the substrate processing device 1, the flow rate of the processing fluid in a supercritical state supplied into the main body 31 during the pressure boosting process can be adjusted. For example, the processing fluid can be supplied at a smaller first flow rate, then the processing fluid can be supplied at a larger second flow rate, and then the processing fluid can be supplied at an even larger third flow rate. Sometimes a fine pattern is formed on the surface of the wafer W moved into the main body 31. In this case, when the processing fluid is supplied at a larger flow rate, the pattern may collapse. In contrast, by supplying at the first flow rate before supplying at the second flow rate, the pattern collapse can be suppressed, and the processing fluid in a supercritical state can be spread between the patterns, and the pattern collapse can be suppressed even when the second and third flow rates are supplied. Moreover, since the processing fluid can be supplied at a second flow rate and a third flow rate that are larger than the first flow rate, after the processing fluid in a supercritical state spreads between the patterns, the time required for pressure boosting can be shortened by supplying the processing fluid at the second and third flow rates.

[0160] Furthermore, in the substrate processing apparatus 1, the heater 68 is disposed at a position downstream (on the main body 31 side) of the first flow rate adjustment unit 250. Therefore, it is easy to stabilize the temperature of the processing fluid in a supercritical state when it is supplied into the main body 31. In particular, excellent temperature uniformity can be obtained between the plurality of drying units 18A to 18C.

[0161] In addition, the supply unit 19 is provided with a third flow adjustment section 150A to 150C, so that the flow rate (circulation flow rate) of the treatment fluid circulating through the first branch pipeline 73A to 73C can be stabilized. For example, when the pressure is increased at the first flow rate, the pressure in the main body 31 is low, and the pressure of the treatment fluid at the branch point 62A is also low, so the differential pressure between the upstream side and the downstream side of the throttling member 120 becomes larger. In this case, in the present embodiment, by setting the valves 111 to 113 to the closed state, the circulation flow rate can also be reduced and the load of the pump 67 can be suppressed. In addition, when the pressure is increased at the second flow rate, by appropriately opening the valves 111 to 113 according to the differential pressure between the upstream side and the downstream side of the throttling member 120, the treatment fluid can continue to flow through the first branch pipeline 73A and the second branch pipeline 74.

[0162] It should be understood that the embodiments disclosed herein are illustrative in all aspects and are not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the appended claims and the gist thereof.

[0163] For example, in the pressure-increasing process, the control unit 7 may adjust the back pressure valve 231 based on the first pressure P1 and the second pressure P2 in the same manner as in the flow process when the first pressure P1 and the second pressure P2 are above a given pressure. 2In the case of , the given pressure may be 6.0 MPa. In this case, the treatment fluid in the second supply line 72A upstream of the heater 68 is in a liquid state, so it is easy to calculate the flow coefficient Cd. The given pressure may also be the critical pressure of the treatment fluid.

[0164] For example, the process fluid used in the drying process may also be CO 2 Any fluid that can remove the drying prevention liquid contained in the wafer W in a supercritical state can be used as the processing fluid. In addition, the drying prevention liquid is not limited to IPA, and any liquid that can be used as the drying prevention liquid can be used. The substrate to be processed is not limited to the above-mentioned wafer W, and can also be other substrates such as a glass substrate for LCD, a ceramic substrate, etc.

Claims

1. A substrate processing device, comprising: A processing container having a processing space capable of accommodating a substrate whose surface is wetted with a liquid; and a processing fluid supply unit for supplying a processing fluid in a supercritical state to the processing container, The processing fluid supply unit comprises: a fluid supply pipeline, one end of which is connected to a fluid supply source, and the other end of which is connected to the processing container; a pump disposed in the fluid supply line; a heating unit, which is disposed in the fluid supply pipeline and at the downstream side of the pump, and heats the treatment fluid to generate the treatment fluid in a supercritical state; a first flow rate adjustment unit, which is disposed in the fluid supply pipeline and between the pump and the heating unit, and adjusts the supply flow rate of the processing fluid supplied to the processing container; a first pressure measuring unit, which is disposed in the fluid supply line and between the first flow rate adjusting unit and the heating unit, and measures the pressure of the treatment fluid; a second pressure measuring unit, which is disposed in the fluid supply line and between the pump and the first flow rate adjusting unit, and measures the pressure of the treatment fluid; a branch point disposed between the pump and the first flow rate adjustment portion in the fluid supply line; a connection point disposed on an upstream side of the pump in the fluid supply line; a branch pipeline connecting the branch point with the connection point; a second flow rate adjustment unit, which is disposed in the branch pipeline and adjusts the supply flow rate of the processing fluid supplied to the processing container; as well as A control unit controls the second flow rate adjustment unit based on the first pressure of the treatment fluid in a liquid state measured by the first pressure measuring unit and the second pressure of the treatment fluid in a liquid state measured by the second pressure measuring unit.

2. The substrate processing apparatus according to claim 1, wherein: The treatment fluid is carbon dioxide, The control unit controls the second flow rate adjustment unit based on the first pressure and the second pressure when the first pressure and the second pressure are 6.0 MPa or more.

3. The substrate processing apparatus according to claim 1, wherein: The first flow rate adjustment unit comprises: A first on-off valve provided in the fluid supply line; and A first throttle portion is connected in series with the first on-off valve.

4. The substrate processing apparatus according to claim 1, wherein: The substrate processing apparatus includes a discharge unit for discharging the processing fluid from the processing container. The discharge portion has: a discharge pipeline connected to the processing container; as well as a flow meter disposed in the discharge line to measure a discharge flow rate of the treatment fluid discharged from the treatment container, The control unit calculates a coefficient of a calculation formula representing a relationship between the supply flow rate and the differential pressure based on the differential pressure between the second pressure and the first pressure and the discharge flow rate.

5. The substrate processing apparatus according to claim 4, wherein: The control unit performs the following processing: (a) before supplying the treatment fluid into the treatment container, heating the treatment fluid and keeping it on standby; (b) supplying the processing fluid into the processing container to increase the pressure in the processing container to a processing pressure; (c) supplying the processing fluid into the processing container and discharging the processing fluid in the processing container from the discharge portion; as well as (d) stopping the supply of the processing fluid into the processing container and discharging the processing fluid in the processing container from the discharge portion, In the above (c), the control unit controls the second flow rate adjustment unit based on the first pressure and the second pressure.

6. The substrate processing apparatus according to claim 5, wherein: The discharge portion has: a third pressure measuring unit, which is disposed in the discharge line and measures the pressure in the processing container; as well as A pressure regulating unit is provided in the discharge line to regulate the pressure in the processing container. In the above (c), the control unit controls the pressure adjustment unit based on the pressure in the processing container measured by the third pressure measurement unit.

7. The substrate processing apparatus according to claim 6, wherein: The (b) has: (b1) increasing the pressure in the processing container to the critical pressure of the processing fluid; (b2) increasing the pressure in the processing container from the critical pressure of the processing fluid to the processing pressure, In the above (b2), the control unit controls the second flow rate adjustment unit based on the first pressure and the second pressure.

8. The substrate processing apparatus according to any one of claims 1 to 7, wherein: The processing fluid supply unit comprises: a cooling unit, which is disposed in the fluid supply pipeline and cools the treatment fluid in a gas state to generate the treatment fluid in a liquid state; as well as A pump is provided in the fluid supply line and at a downstream side of the cooling unit.

9. A fluid supply system for supplying a processing fluid in a supercritical state to a processing container having a processing space capable of accommodating a substrate whose surface is wetted by the liquid, comprising: a fluid supply pipeline, one end of which is connected to a fluid supply source, and the other end of which is connected to the processing container; a pump disposed in the fluid supply line; a heating unit, which is disposed in the fluid supply pipeline and at the downstream side of the pump, and heats the treatment fluid to generate the treatment fluid in a supercritical state; a first flow rate adjustment unit, which is disposed in the fluid supply pipeline and between the pump and the heating unit, and adjusts the supply flow rate of the processing fluid supplied to the processing container; a first pressure measuring unit, which is disposed in the fluid supply line and between the first flow rate adjusting unit and the heating unit, and measures the pressure of the treatment fluid; a second pressure measuring unit, which is disposed in the fluid supply line and between the pump and the first flow rate adjusting unit, and measures the pressure of the treatment fluid; a branch point disposed between the pump and the first flow rate adjustment portion in the fluid supply line; a connection point disposed on an upstream side of the pump in the fluid supply line; a branch pipeline connecting the branch point with the connection point; a second flow rate adjustment unit, which is disposed in the branch pipeline and adjusts the supply flow rate of the processing fluid supplied to the processing container; as well as A control unit controls the second flow rate adjustment unit based on the first pressure of the treatment fluid in a liquid state measured by the first pressure measuring unit and the second pressure of the treatment fluid in a liquid state measured by the second pressure measuring unit.

10. The fluid supply system according to claim 9, wherein: The treatment fluid is carbon dioxide, The control unit controls the second flow rate adjustment unit based on the first pressure and the second pressure when the first pressure and the second pressure are 6.0 MPa or more.

11. The fluid supply system according to claim 9, wherein: The first flow rate adjustment unit comprises: A first on-off valve provided in the fluid supply line; and A first throttle portion is connected in series with the first on-off valve.

12. The fluid supply system according to any one of claims 9 to 11, wherein: The fluid supply system comprises: a cooling unit, which is disposed in the fluid supply pipeline and cools the treatment fluid in a gas state to generate the treatment fluid in a liquid state; as well as A pump is provided in the fluid supply line and at a downstream side of the cooling unit.

13. A substrate processing method using a substrate processing device, the substrate processing device comprising: A processing container having a processing space capable of accommodating a substrate whose surface is wetted with a liquid; and a processing fluid supply unit for supplying a processing fluid in a supercritical state to the processing container, The processing fluid supply unit comprises: a fluid supply pipeline, one end of which is connected to a fluid supply source, and the other end of which is connected to the processing container; a pump disposed in the fluid supply line; a heating unit, which is disposed in the fluid supply pipeline and at the downstream side of the pump, and heats the treatment fluid to generate the treatment fluid in a supercritical state; a first flow rate adjustment unit, which is disposed in the fluid supply pipeline and between the pump and the heating unit, and adjusts the supply flow rate of the processing fluid supplied to the processing container; a first pressure measuring unit, which is disposed in the fluid supply line and between the first flow rate adjusting unit and the heating unit, and measures the pressure of the treatment fluid; a second pressure measuring unit, which is disposed in the fluid supply line and between the pump and the first flow rate adjusting unit, and measures the pressure of the treatment fluid; a branch point disposed between the pump and the first flow rate adjustment portion in the fluid supply line; a connection point disposed on an upstream side of the pump in the fluid supply line; a branch line connecting the branch point with the connection point; and a second flow rate adjustment unit, which is provided in the branch pipeline and adjusts the supply flow rate of the processing fluid supplied to the processing container; The substrate processing method has the following processing: The second flow rate adjustment unit is controlled based on a first pressure of the treatment fluid in a liquid state measured by the first pressure measurement unit and a second pressure of the treatment fluid in a liquid state measured by the second pressure measurement unit.

14. The substrate processing method according to claim 13, wherein: The treatment fluid is carbon dioxide, When the first pressure and the second pressure are 6.0 MPa or more, the second flow rate adjustment unit is controlled based on the first pressure and the second pressure.

15. The substrate processing method according to claim 13, wherein: The first flow rate adjustment unit comprises: A first on-off valve provided in the fluid supply line; and A first throttle portion is connected in series with the first on-off valve.

16. The substrate processing method according to claim 13, wherein: The substrate processing apparatus includes a discharge unit for discharging the processing fluid from the processing container. The discharge portion has: a discharge pipeline connected to the processing container; as well as a flow meter disposed in the discharge line to measure a discharge flow rate of the treatment fluid discharged from the treatment container, In the substrate processing method, a coefficient of a calculation formula representing a relationship between the supply flow rate and the differential pressure is calculated based on the differential pressure between the second pressure and the first pressure and the discharge flow rate.

17. The substrate processing method according to claim 16, comprising the following steps: (a) before supplying the treatment fluid into the treatment container, heating the treatment fluid and keeping it on standby; (b) supplying the processing fluid into the processing container to increase the pressure in the processing container to a processing pressure; (c) supplying the processing fluid into the processing container and discharging the processing fluid in the processing container from the discharge portion; as well as (d) stopping the supply of the processing fluid into the processing container and discharging the processing fluid in the processing container from the discharge portion, In (c) above, the second flow rate adjustment unit is controlled based on the first pressure and the second pressure.

18. The substrate processing method according to claim 17, wherein: The discharge portion has: a third pressure measuring unit, which is provided in the discharge line and measures the pressure in the processing container; and A pressure regulating unit is provided in the discharge line to regulate the pressure in the processing container. In the above (c), the pressure adjustment unit is controlled based on the pressure in the processing container measured by the third pressure measurement unit.

19. The substrate processing method according to claim 18, wherein: The (b) has: (b1) increasing the pressure in the processing container to the critical pressure of the processing fluid; (b2) increasing the pressure in the processing container from the critical pressure of the processing fluid to the processing pressure, In (b2) above, the second flow rate adjustment unit is controlled based on the first pressure and the second pressure.

20. The substrate processing method according to any one of claims 13 to 19, wherein: The processing fluid supply unit comprises: a cooling unit, which is disposed in the fluid supply pipeline and cools the treatment fluid in a gas state to generate the treatment fluid in a liquid state; as well as A pump is provided in the fluid supply line and at a downstream side of the cooling unit.

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