Substrate processing apparatus and substrate processing method
By setting a bypass line in the substrate processing device, the roundabout buffer tank supplies supercritical fluid to the chamber, achieving rapid reach of process pressure, solving the problem of long supply of supercritical fluid in the prior art, and improving process efficiency and production volume .
Patent Information
- Application Number
- CN202410744420.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-06-12
- Filing Date
- 2024-06-11
- Publication Date
- 2024-12-13
AI Technical Summary
When substrate processing is used with supercritical fluid, it takes a long time to reach the process pressure during the supply of supercritical fluid to the interior of the chamber, resulting in extended process time and reduced throughput.
By providing a bypass line in the main supply line, the detour buffer tank supplies supercritical fluid to the chamber, and the fluid is supplied from the buffer tank and the bypass line to the chamber, respectively, and the chamber and buffer are controlled. The pressure difference of the tank is to quickly reach the process pressure.
The time to reach process pressure is shortened, the overall process efficiency and production volume is improved, and the passing rate of substrate processing is significantly improved.
Smart Images
Figure CN119133001A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a substrate processing device and a substrate processing method, and more particularly, to a substrate processing device and a substrate processing method in which a process pressure can be reached more quickly when a supercritical fluid is supplied to the interior of a chamber in a substrate processing device using a supercritical fluid, thereby shortening the process time and improving throughput. Background Art
[0002] Generally, when manufacturing a large-scale / high-density semiconductor device such as LSI (Large scale integration) on the surface of a semiconductor wafer, it is necessary to form an extremely fine pattern on the wafer surface.
[0003] Such microscopic patterns are formed by various processes of exposing, developing, and cleaning a wafer coated with a photoresist, patterning the photoresist, and then etching the wafer so that the photoresist pattern can be transferred to the wafer.
[0004] After such etching, the wafer is cleaned to remove dust or natural oxide film on the surface of the wafer. The cleaning process is performed by immersing the wafer with a pattern formed on the surface into a treatment liquid such as a chemical solution or a rinse liquid or by supplying the treatment liquid to the surface of the wafer.
[0005] However, as semiconductor devices are increasingly integrated, pattern collapse, in which the pattern of the photoresist or the wafer surface collapses, occurs when a processing liquid is dried after a cleaning process.
[0006] Such a pattern collapse is equivalent to, for example Fig.11 As shown, when the cleaning process is completed and the processing liquid 10 remaining on the surface of the substrate S is dried, if the processing liquid on the left and right of the patterns 11, 12, and 13 is not dried evenly, the capillary force of the left and right stretching patterns 11, 12, and 13 is unbalanced, resulting in the phenomenon that the patterns 11, 12, and 13 collapse in the direction where more processing liquid remains.
[0007] exist Fig.11 In the case of , the drying of the processing liquid in the left and right outer regions where no pattern is formed on the substrate S is completed, and the processing liquid 10 remains in the gaps between the patterns 11, 12, and 13. As a result, the patterns 11 and 13 on the left and right sides collapse inward due to the capillary force received from the processing liquid 10 remaining between the patterns 11, 12, and 13.
[0008] The capillary force causing the aforementioned pattern collapse is due to the surface tension of the processing liquid acting in the liquid / gas interface between the atmosphere surrounding the substrate S after the cleaning process and the processing liquid remaining between the patterns.
[0009] Therefore, a treatment method for drying a treatment liquid using a fluid in a supercritical state (hereinafter referred to as a "supercritical fluid") that does not form an interface with a gas or a liquid has recently attracted attention.
[0010] exist Fig.12 In the state diagram of pressure and temperature, in the drying method of the prior art using only temperature regulation, the gas-liquid equilibrium line must be passed as shown by the hidden line, and therefore, capillary force is generated at the gas-liquid interface at this time.
[0011] In contrast, when drying is performed through a supercritical state by adjusting the temperature and pressure of the fluid, the gas-liquid equilibrium line is not passed, and the substrate can be dried essentially in a state without capillary force.
[0012] Reference Fig.12 To observe the drying using supercritical fluid, if the pressure of the liquid is raised from A to B, and then the temperature is raised from B to C, it will not pass through the gas-liquid equilibrium line and will be converted to the supercritical state C. In addition, when the drying process is completed, the pressure of the supercritical fluid is reduced and it will not pass through the gas-liquid equilibrium line and will be converted into gas D.
[0013] On the other hand, when using a supercritical fluid, a pump for supplying the supercritical fluid and a buffer tank for containing the supercritical fluid are provided, and the supercritical fluid is supplied from the buffer tank to the chamber by the pump and pressurized. In this case, the buffer tank and the chamber are pressurized simultaneously by the pump, so that it takes a long time to reach the process pressure in the chamber, and the overall process time is extended, resulting in a decrease in throughput. Summary of the invention
[0014] In order to solve the above-mentioned problems, the present invention aims to provide a substrate processing device and a substrate processing method which can shorten the time to reach the process pressure and shorten the overall process time to improve the throughput when a supercritical fluid is supplied to a chamber and pressurized to the process pressure.
[0015] It may be that the purpose of the present invention as described above is achieved by a substrate processing device, which comprises: a chamber, which provides a processing space for performing a processing process on a substrate coated with a processing liquid or an organic solvent using a fluid in a supercritical state; and a fluid supply unit, which supplies the fluid to the chamber, and the fluid supply unit comprises: a fluid storage unit, which stores the fluid; a main supply line, which connects the fluid storage unit and the chamber; a pump, which is arranged in the main supply line and pressurizes the fluid in the fluid storage unit and supplies it toward the chamber; a buffer tank, which is arranged at the rear end of the pump in the main supply line and contains the fluid; and a bypass line, which bypasses the buffer tank and connects the pump and the chamber.
[0016] Here, the bypass line may be branched from the main supply line between the pump and the buffer tank and merged with the main supply line between the buffer tank and the chamber.
[0017] Furthermore, a first throttle hole may be further provided between the buffer tank and the chamber, and the bypass line may merge with the main supply line at a front end of the first throttle hole.
[0018] Furthermore, a first throttle hole may be provided between the buffer tank and the chamber, and the bypass line may merge with the main supply line at the rear end of the first throttle hole. In this case, a second throttle hole may be provided on the bypass line.
[0019] On the other hand, when the fluid is supplied to the chamber and pressurized to a predetermined process pressure, it may include a first pressurizing step of supplying the fluid from the buffer tank to the chamber and a second pressurizing step of supplying the fluid to the chamber through the bypass line.
[0020] Here, the time point of switching from the first pressurizing step to the second pressurizing step may be determined by at least one of a preset time of the first pressurizing step or the second pressurizing step, a pressure value inside the chamber, a pressure change rate inside the chamber, a pressure value inside the buffer tank, a pressure change rate inside the buffer tank, and a pressure difference between the chamber and the buffer tank.
[0021] Furthermore, when the pressure inside the chamber reaches a predetermined process pressure and a processing process for the substrate is performed, the fluid may be supplied toward the chamber through the bypass line and discharged from the chamber.
[0022] Furthermore, when the fluid is discharged from the interior of the chamber, the fluid may be discharged from the interior of the chamber and the fluid may be supplied to the buffer tank.
[0023] On the other hand, the object of the present invention as described above may be achieved by a substrate processing method of a substrate processing device having a chamber that performs a processing process for a substrate using a fluid in a supercritical state, the substrate processing method comprising: a pressurizing step of supplying the fluid toward the chamber and pressurizing it to a predetermined process pressure; a process step of performing a processing process for the substrate; and a decompression step of discharging the fluid from the inside of the chamber, the pressurizing step comprising: a first pressurizing step of supplying the fluid from a buffer tank to the chamber; and a second pressurizing step of supplying the fluid to the chamber through a bypass line that bypasses the buffer tank.
[0024] Here, the time point of switching from the first pressurizing step to the second pressurizing step may be determined by at least one of a preset time of the first pressurizing step or the second pressurizing step, a pressure value inside the chamber, a pressure change rate inside the chamber, and an internal pressure difference between the chamber and the buffer tank.
[0025] In addition, it may be that, in the process step, the fluid is supplied toward the chamber and discharged from the chamber through the bypass line.
[0026] Furthermore, in the decompression step, the fluid may be discharged from the interior of the chamber and supplied to the buffer tank.
[0027] According to the present invention having the aforementioned structure, when a supercritical fluid is supplied to a chamber and pressurized to a process pressure, the supercritical fluid is supplied to the chamber via a bypassing buffer tank, thereby reducing the time to reach the process pressure and shortening the overall process time to improve throughput. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 is a block diagram showing the structure of a substrate processing apparatus using a supercritical fluid according to the prior art,
[0029] Figure 2 It is shown in Figure 1 A graph showing the pressure changes in the chamber and buffer tank.
[0030] Figure 3 is a block diagram showing the structure of a substrate processing apparatus using a supercritical fluid according to an embodiment of the present invention,
[0031] Figure 4 is a block diagram showing the structure of a substrate processing apparatus using a supercritical fluid according to another embodiment of the present invention,
[0032] Figure 5 It is shown in Figure 3 A graph showing the pressure changes in the chamber and buffer tank.
[0033] Figures 6 to 10 is a diagram for explaining the operation of a substrate processing apparatus in each step of a processing process for a substrate.
[0034] Fig.11 is a diagram schematically showing a state in which a pattern collapses when a pattern on a substrate is dried according to the prior art.
[0035] Fig.12 This is a state diagram showing changes in pressure and temperature of a fluid in a process using a supercritical fluid.
[0036] (Explanation of Reference Numerals)
[0037] S: Substrate
[0038] 100: Fluid storage unit
[0039] 120: Main supply line
[0040] 122: First valve
[0041] 124: Second valve
[0042] 130: Bypass line
[0043] 132: The third valve
[0044] 140: discharge line
[0045] 142: Discharge valve
[0046] 200: Temperature control unit
[0047] 300: Pressure regulation unit
[0048] 400: Chamber
[0049] 412: Processing Space
[0050] 450: Pallet
[0051] 500: Buffer tank
[0052] 600: Fluid Supply Department
[0053] 1000: Substrate processing equipment DETAILED DESCRIPTION
[0054] Hereinafter, the structure of a substrate processing apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0055] Figure 1 is a block diagram showing a structure of a substrate processing apparatus 1000 according to the related art.
[0056] The substrate processing apparatus 1000 using supercritical fluid uses a fluid in a supercritical state to perform a processing process for a substrate S. Here, if the fluid in a supercritical state refers to a substance reaching a critical state, that is, reaching a state exceeding a critical temperature and a critical pressure, it is equivalent to a fluid having a formed phase. Such a fluid in a supercritical state has a molecular density close to that of a liquid and a viscosity close to that of a gas. Therefore, the diffusion force, penetration force, and solubility of the fluid in a supercritical state are very excellent, which is conducive to chemical reactions and has almost no surface tension and does not exert surface tension on fine structures. Therefore, in the drying process of semiconductor elements, not only is the drying efficiency excellent, but the pattern collapse phenomenon can also be avoided and it can be used very usefully.
[0057] In the present invention, carbon dioxide (CO2) can be used as a supercritical fluid. Carbon dioxide has a relatively low critical temperature of approximately 31.1°C and a relatively low critical pressure of 7.38 MPa, and has the advantages of being easy to become a supercritical state, being easy to control its state by adjusting the temperature and pressure, and being inexpensive.
[0058] In addition, carbon dioxide is non-toxic, harmless to the human body, and has non-flammable and inactive properties. Furthermore, the diffusion coefficient of carbon dioxide in a supercritical state is about 10 to 100 times higher than that of water or other organic solvents, and its permeability is very excellent, so that the replacement of organic solvents is rapid and there is almost no surface tension, which is beneficial for use in the drying process. In addition, the carbon dioxide used in the drying process can be converted into a gas state and the organic solvent can be separated for reuse, so the burden on environmental pollution is also small.
[0059] Reference Figure 1 The substrate processing device 1000 may include: a chamber 400, which provides a processing space 412 for performing a processing process on a substrate S coated with a processing liquid or an organic solvent 10 (hereinafter referred to as "organic solvent") using a supercritical fluid; and a fluid supply unit 600, which supplies fluid to the chamber 400.
[0060] The fluid supply part 600 may adjust at least one of the temperature and the pressure of the fluid to supply the fluid to the chamber 400 through the main supply line 120 .
[0061] For example, the fluid supply unit 600 may include: a fluid storage unit 100 storing the fluid; and a main supply line 120 connecting the fluid storage unit 100 and the chamber 400 .
[0062] In this case, a temperature adjustment unit 200 and a pump 300 for adjusting the pressure may be arranged along the main supply line 120. In this case, the temperature adjustment unit 200 may be composed of a heater or a heat exchanger for heating the fluid.
[0063] Furthermore, the main supply line 120 may further include a sensing unit (not shown) for sensing at least one of the pressure and the temperature of the fluid. The pressure and the temperature of the fluid flowing in the main supply line 120 may be adjusted according to the pressure and the temperature sensed in the sensing unit. To this end, the substrate processing apparatus 1000 according to an embodiment of the present invention may include a control unit (not shown) for controlling the pump 300 and the temperature adjustment unit 200. The control unit may control the pump 300 and the temperature adjustment unit 200 based on the pressure and the temperature sensed in the sensing unit.
[0064] On the other hand, when performing a processing process on the substrate S, the temperature and pressure of the processing space 412 of the chamber 400 must be maintained above the critical temperature and the critical pressure so that the fluid supplied to the inside of the chamber 400 can be converted into a supercritical state.
[0065] To this end, when the fluid moves along the main supply line 120 , the fluid may be pressurized to a critical pressure or a pressure above the critical pressure by the pump 300 , and further, the fluid may be heated to a critical temperature or a temperature above the critical temperature by the temperature adjustment unit 200 .
[0066] On the other hand, the main supply line 120 may further include a buffer tank 500 for storing the fluid. The buffer tank 500 stores the fluid and serves to more quickly supply the fluid to the chamber 400.
[0067] For example, the internal space of the buffer tank 500 may have a larger volume than the internal space of the chamber 400. Thus, the fluid in the buffer tank 500 having a larger capacity than the chamber 400 is supplied to the chamber 400, so that the fluid can be supplied more quickly.
[0068] In this case, the buffer tank 500 may be disposed at the rear end of the pump 300 in the main supply line 120. In addition, a first valve 122 for controlling the flow of the fluid may be provided at the front end of the buffer tank 500, and a second valve 124 for controlling the supply of the fluid may be provided at the rear end of the buffer tank 500.
[0069] On the other hand, the chamber 400 is further provided with a discharge line 140 for discharging the fluid in the processing space 412 to the outside. During or after the processing of the substrate S, the fluid can be discharged from the inside of the chamber 400 to the outside through the discharge line 140. The discharge line 140 can be provided with a discharge valve 142, which can be composed of a proportional control valve, for example.
[0070] On the other hand, the chamber 400 may provide a processing space 412 for performing a processing process such as a drying process on the substrate S using a fluid in a supercritical state. The chamber 400 may have an opening (not shown) formed at one side and may be made of a material suitable for processing a high-pressure process on the substrate S inside.
[0071] The processing space 412 of the chamber 400 may be kept sealed, and the pressure of the fluid supplied to the processing space 412 may be kept above a critical pressure.
[0072] In addition, the chamber 400 may further include a heating unit (not shown) to maintain the temperature of the processing space 412 at a predetermined temperature or above. The heating unit may maintain the temperature of the processing space 412 or the temperature of the fluid contained in the processing space 412 at a critical temperature or above during the process of the substrate S.
[0073] On the other hand, the chamber 400 may include a tray 450 for supporting the substrate S.
[0074] The tray 450 may be introduced into the processing space 412 of the chamber 400 through the opening of the chamber 400 or may be introduced from the processing space 412 to the outside of the chamber 400 through the opening.
[0075] Figure 2 is a graph showing changes in pressure inside the buffer tank 500 and the chamber 400 according to a process for the substrate S in the substrate processing apparatus 1000 .
[0076] Hereinafter, a processing process of the substrate S in the substrate processing apparatus 1000 will be described with reference to the accompanying drawings.
[0077] Reference Figure 1 and Figure 2 In the case of the preparation step (D1: 0-T1) in which the tray 450 is inserted into and docked with the chamber 400 at the start of the process for the substrate S, the pressure inside the chamber 400 may be equivalent to the atmospheric pressure Pa0. In addition, the buffer tank 500 has already contained the fluid inside, so that the preset initial pressure Pb0 can be maintained.
[0078] In this case, the first valve 122 is kept in an open state, and the second valve 124 is kept in a closed state.
[0079] Next, a pressurizing step (D2: T1-T2) is performed to increase the pressure inside the chamber 400.
[0080] In the pressurizing step, the second valve 124 is opened and the high-pressure fluid in the buffer tank 500 is supplied to the inside of the chamber 400 by driving the pump 300, and the fluid is not discharged from the chamber 400. Therefore, the pressure inside the chamber 400 increases and reaches the preset process pressure Pa1.
[0081] More specifically, if the high-pressure fluid in the buffer tank 500 is supplied to the chamber 400 by driving the pump 300, the internal pressure of the buffer tank 500 decreases sharply at the beginning of the pressurization step, and conversely, the pressure inside the chamber 400 increases sharply.
[0082] Next, in the second half of the pressurization step, the pressure of the buffer tank 500 rises again as the fluid is continuously supplied from the fluid storage unit 100 by the drive of the pump 300. In addition, the pressure inside the chamber 400 continues to rise, but the closer it is to the process pressure, the slower the rise rate is than the initial rise rate.
[0083] When the internal pressures of the buffer tank 500 and the chamber 400 reach the preset process pressure Pa1, the pressurizing step is completed.
[0084] Following the pressurization step, a pressure maintaining step (or isobaric step) (D3: T2-T3) is performed. In the pressure maintaining step, the discharge valve 142 is opened. Therefore, while the fluid is continuously supplied to the interior of the chamber 400, the fluid equivalent to the amount of the supplied fluid is discharged to the outside of the chamber 400 through the discharge line 140 to keep the pressure inside the chamber 400 constant.
[0085] The pressure maintaining step is followed by a decompression step (D4: T3-T4). In the decompression step, the second valve 124 is closed and no fluid is supplied to the interior of the chamber 400, and the fluid is discharged to the outside of the chamber 400 through the discharge line 140, thereby reducing the pressure inside the chamber 400.
[0086] In this case, the second valve 124 is in a closed state, and therefore, when the pressure of the buffer tank 500 increases and reaches the initial pressure Pb0, the first valve 122 may be closed.
[0087] On the other hand, as described above, in the pressurizing step (D2: T1-T2), the pressure inside the chamber 400 rises sharply at the initial stage, but the pressure rise rate inside the chamber 400 decreases as it approaches the process pressure Pa1 in the latter half. This is because the buffer tank 500 and the chamber 400 are connected, and the buffer tank 500 and the chamber 400 are all pressurized by the pump 300. In particular, as described above, the buffer tank 500 has a larger capacity than the chamber 400, so a large load is generated on the pump 300, and thus, the time to reach the process pressure inside the chamber 400 may be delayed, thereby increasing the overall process time and reducing the throughput.
[0088] Figure 3 2 is a block diagram showing the structure of a substrate processing apparatus 2000 according to the present invention for solving the aforementioned problems. Figure 3 In the above Figure 1 The same reference numerals are used for the same components.
[0089] Reference Figure 3 The substrate processing apparatus 2000 may include a bypass line 130 that bypasses the buffer tank 500 and connects the pump 300 and the chamber 400 .
[0090] For example, the bypass line 130 may branch from the main supply line 120 between the pump 300 and the buffer tank 500 and merge with the main supply line 120 between the buffer tank 500 and the chamber 400. More specifically, the bypass line 130 may branch at the front end of the aforementioned first valve 122 and merge with the rear end of the aforementioned second valve 124.
[0091] In this case, the bypass line 130 may be provided with a third valve 132 for controlling the flow of the fluid.
[0092] On the other hand, a first throttle hole 150 may be disposed at the rear end of the second valve 124 to adjust the flow rate or pressure of the fluid supplied to the chamber 400 to prevent the substrate S from being damaged by a sudden supply of fluid to the chamber 400.
[0093] For example, the bypass line 130 may merge with the main supply line 120 at the front end of the first throttle hole 150 . More specifically, the bypass line 130 may merge with the main supply line 120 between the rear end of the second valve 124 and the front end of the first throttle hole 150 .
[0094] In this case, there is an advantage that when the fluid is supplied through the buffer tank 500 or the bypass line 130 , the flow rate or pressure of the fluid can also be adjusted entirely through the first throttle hole 150 .
[0095] on the other hand, Figure 4 is a block diagram showing the structure of a substrate processing apparatus 3000 according to another embodiment of the present invention. Figure 4 The same reference numerals are used for the same components as those in the aforementioned embodiment.
[0096] Reference Figure 4 In this embodiment, the bypass line 130 may merge with the main supply line 120 at the rear end of the first throttle hole 150. In addition, the bypass line 130 may be provided with a second throttle hole 152.
[0097] In this case, the flow rate and pressure of the fluid supplied through the buffer tank 500 may be adjusted through the first throttle hole 150 , and the flow rate and pressure of the fluid supplied through the bypass line 130 may be adjusted through the second throttle hole 152 .
[0098] Furthermore, the sizes or dimensions of the inner diameters of the first throttle hole 150 and the second throttle hole 152 may be determined to be the same, but may also be different from each other. In the case where the inner diameters of the first throttle hole 150 and the second throttle hole 152 are different, there is an advantage that the flow rates and pressures of the fluid supplied through the buffer tank 500 and the fluid supplied through the bypass line 130 can be adjusted differently.
[0099] exist Figure 3 and Figure 4 In the substrate processing apparatus 2000, 3000, the buffer tank 500 can be bypassed in the pressurization step of the substrate processing process and a high-pressure fluid can be supplied to the chamber 400 through the bypass line 130 to shorten the time of the pressurization step, thereby shortening the overall process time by more than 50% compared with the prior art. The following will be specifically observed.
[0100] Figure 5 is a graph showing changes in pressure inside the buffer tank 500 and the chamber 400 according to a process for the substrate S in the aforementioned substrate processing apparatus 2000, Figures 6 to 10 2 is a diagram for explaining the operation of the substrate processing apparatus 2000 in each step of the processing process for the substrate S. Figures 6 to 10 For the sake of convenience, the aforementioned throttle hole is omitted.
[0101] Reference Figures 5 and 6 In the case of the preparation step (D1: 0~T1) in which the process for the substrate S starts and the tray 450 is inserted into and docked with the chamber 400, the pressure inside the chamber 400 can be equivalent to the atmospheric pressure Pa0, and the buffer tank 500 has already contained the fluid inside and can maintain a preset initial pressure Pb0.
[0102] In this case, the first valve 122 is kept in an open state, and the second valve 124 and the third valve 132 are kept in a closed state.
[0103] Next, refer to Figure 5 , Figures 7 and 8 , followed by a pressurizing step (D2: T1 to T2') in which the pressure inside the chamber 400 is increased.
[0104] In the substrate processing device 2000 according to the present invention, the pressurizing step may include: a first pressurizing step (D21: T1~Tt), supplying the fluid from the buffer tank 500 to the chamber 400; and a second pressurizing step (D22: Tt~T2'), supplying the fluid to the chamber 400 through the bypass line 130 bypassing the buffer tank 500.
[0105] First, in the first pressurizing step, Figure 7 As shown, the second valve 124 is opened and the high-pressure fluid in the buffer tank 500 is supplied to the interior of the chamber 400 by driving the aforementioned pump 300. Therefore, the pressure inside the chamber 400 increases.
[0106] Next, the first pressurizing step may be switched to the second pressurizing step. Here, the time point Tt at which the first pressurizing step is switched to the second pressurizing step may be determined by at least one of the preset time of the first pressurizing step or the second pressurizing step, the pressure value inside the chamber 400, the pressure change rate (or pressure rise rate) inside the chamber 400, the pressure value inside the buffer tank 500, the pressure change rate inside the buffer tank 500, and the internal pressure difference between the chamber 400 and the buffer tank 500.
[0107] For example, if the time of the first pressurizing step is preset and exceeds the preset time, the process may be switched to the second pressurizing step.
[0108] Alternatively, when the pressure value inside the chamber 400 is compared with a preset reference pressure value Pt1, if the pressure value inside the chamber 400 reaches the reference pressure value, the second pressurization step may be performed. Here, the reference pressure value may be set to, for example, a critical pressure value of the fluid, but this is only an example and may be set in various ways according to the processing process for the substrate S.
[0109] In addition, the pressure change rate (or pressure rise rate) inside the chamber 400 may be sensed and the second pressurizing step may be switched according to the pressure rise rate inside the chamber 400. For example, in the case where the fluid is supplied to the chamber 400 through the bypass line 130 in the second pressurizing step, the pressure rise rate inside the chamber 400 (hereinafter referred to as the "second pressure rise rate") may be preset. Therefore, in the aforementioned first pressurizing step, when the pressure rise rate inside the chamber 400 (hereinafter referred to as the "first pressure rise rate") is compared with the second pressure rise rate, and the first pressure rise rate is less than the second pressure rise rate, the second pressurizing step may be switched.
[0110] In addition, when the pressure value inside the buffer tank 500 is compared with a preset reference pressure value, if the pressure value inside the buffer tank 500 reaches the reference pressure value, the second pressurization step may be switched. Here, the reference pressure value may be set in various ways according to the processing process for the substrate S.
[0111] On the other hand, the pressure change rate (or pressure increase rate) inside the buffer tank 500 may be sensed and switched to the second pressurizing step according to the pressure increase rate inside the buffer tank 500 .
[0112] Furthermore, when the internal pressure difference between the chamber 400 and the buffer tank 500 is compared with a preset reference value and the internal pressure difference between the chamber 400 and the buffer tank 500 is less than the reference value, the process may be switched to the second pressurizing step.
[0113] In the aforementioned second pressurizing step, if Figure 8 As shown, the first valve 122 and the second valve 124 are all closed, and the third valve 132 is opened.
[0114] Therefore, the high-pressure fluid supplied by the driving of the pump 300 can be detoured and supplied to the chamber 400 through the bypass line 130 without passing through the buffer tank 500. When the fluid is supplied by the driving of the pump 300, the fluid is directly supplied to the chamber 400 without passing through the high-capacity buffer tank 500, so that the pressure inside the chamber 400 can be increased more rapidly.
[0115] In this case, if Figure 5 As shown in FIG. 1 , the pressure rise rate inside the chamber 400 after the time point Tt at which the first pressurization step is switched to the second pressurization step is greater than that observed previously. Figure 2 The latter half of the pressurization step has a relatively larger rising rate. Therefore, the pressure inside the chamber 400 can be higher than that according to Figure 2 The prior art embodiments reach the process pressure Pa1 in a shorter time.
[0116] On the other hand, the pressure inside the buffer tank 500 maintains the pressure Pt2 at the switching time point Tt as it is. Figure 8 As shown, the first valve 122 and the second valve 124 at the front end and the rear end of the buffer tank 500 are all in a closed state.
[0117] When the internal pressure of the chamber 400 reaches the preset process pressure Pa1, the pressurizing step is terminated.
[0118] The pressurization step is followed by a process step (D3: T2' to T3'). In the process step, Fig. 9 As shown, the aforementioned discharge valve 142 is opened. Therefore, while the fluid is continuously supplied to the inside of the chamber 400 through the bypass line 130 , the fluid is discharged to the outside of the chamber 400 through the discharge line 140 .
[0119] In this case, the pressure inside the chamber 400 is kept constant by discharging an amount equivalent to the amount of the fluid supplied to the chamber 400 through the discharge line 140 during the process step.
[0120] Alternatively, in the process step, the pressure inside the chamber 400 is changed in a pulse form to change the pressure inside the chamber 400, so that the fluid can be uniformly diffused and uniformly supplied into the chamber 400.
[0121] Then, the above process steps are followed by a decompression step (D4: T3' to T4'). In the decompression step, Fig.10 As shown, the third valve 132 is closed and no fluid is supplied to the interior of the chamber 400 , and the fluid is discharged to the outside of the chamber 400 through the exhaust line 140 , thereby reducing the pressure inside the chamber 400 .
[0122] In this case, the second valve 124 is in a closed state and the first valve 122 is in an open state. Therefore, when the fluid is supplied to the buffer tank 500 and the internal pressure of the buffer tank 500 increases and reaches the initial pressure Pb0, the first valve 122 may be closed.
[0123] The above description is made with reference to the preferred embodiments of the present invention, but those skilled in the art may make various modifications and changes to the present invention without departing from the concept and scope of the present invention as described in the attached claims. Therefore, if the modified implementation basically includes the constituent elements of the claims of the present invention, it should be deemed that all of them belong to the technical scope of the present invention.
Claims
1. A substrate processing device, characterized in that: have: A chamber providing a processing space for performing a processing process on a substrate coated with a processing liquid or an organic solvent using a fluid in a supercritical state; and a fluid supply unit for supplying the fluid to the chamber, The fluid supply unit comprises: A fluid storage unit for storing the fluid; a main supply line connecting the fluid storage portion and the chamber; a pump, disposed in the main supply line, and pressurizing the fluid in the fluid storage portion and supplying the fluid toward the chamber; a buffer tank disposed at a rear end of the pump in the main supply line and containing the fluid; as well as A bypass line bypasses the buffer tank and connects the pump and the chamber.
2. The substrate processing device according to claim 1, characterized in that: The bypass line branches off from the main supply line between the pump and the buffer tank and merges with the main supply line between the buffer tank and the chamber.
3. The substrate processing device according to claim 2, characterized in that: A first throttle hole is also provided between the buffer tank and the chamber. The bypass line merges with the main supply line at a front end of the first throttle hole.
4. The substrate processing device according to claim 2, characterized in that: A first throttle hole is also provided between the buffer tank and the chamber. The bypass line merges with the main supply line at the rear end of the first throttle hole.
5. The substrate processing device according to claim 4, characterized in that: The bypass line is further provided with a second throttle hole.
6. The substrate processing apparatus according to claim 1, wherein: When the fluid is supplied to the chamber and pressurized to a preset process pressure, The method includes a first pressurizing step of supplying the fluid from the buffer tank toward the chamber and a second pressurizing step of supplying the fluid toward the chamber through the bypass line.
7. The substrate processing device according to claim 6, characterized in that: The time point of switching from the first pressurizing step to the second pressurizing step is determined by at least one of a preset time of the first pressurizing step or the second pressurizing step, a pressure value inside the chamber, a pressure change rate inside the chamber, a pressure value inside the buffer tank, a pressure change rate inside the buffer tank, and a pressure difference between the chamber and the buffer tank.
8. The substrate processing apparatus according to claim 1, wherein: When the pressure inside the chamber reaches a preset process pressure and a processing process is performed on the substrate, The fluid is supplied toward the chamber and exhausted from the chamber through the bypass line.
9. The substrate processing apparatus according to claim 1, wherein: When the fluid is discharged from the interior of the chamber, The fluid is discharged from the interior of the chamber, and the fluid is supplied to the buffer tank.
10. A substrate processing method, which is a substrate processing method of a substrate processing device, wherein the substrate processing device has a chamber for performing a processing process on a substrate using a fluid in a supercritical state, characterized in that: The substrate processing method comprises: a pressurizing step of supplying the fluid toward the chamber to pressurize the fluid to a preset process pressure; a process step of performing a process for the substrate; and a depressurizing step of discharging the fluid from the chamber. The pressurizing step comprises: a first pressurizing step of supplying the fluid from a buffer tank to the chamber; and In the second pressurizing step, the fluid is supplied to the chamber through a bypass line that bypasses the buffer tank.
11. The substrate processing method according to claim 10, characterized in that: The time point of switching from the first pressurizing step to the second pressurizing step is determined by at least one of a preset time of the first pressurizing step or the second pressurizing step, a pressure value inside the chamber, a pressure change rate inside the chamber, and an internal pressure difference between the chamber and the buffer tank.
12. The substrate processing method according to claim 10, characterized in that: In the process step, the fluid is supplied toward the chamber through the bypass line and discharged from the chamber.
13. The substrate processing method according to claim 10, characterized in that: In the depressurizing step, the fluid is exhausted from the interior of the chamber and the fluid is supplied to the buffer tank.