Fluid supply system, substrate processing apparatus, and substrate processing method

Abstract

A fluid supply system according to one aspect of the present disclosure supplies a processing fluid into a processing container in which a substrate on which a liquid film is formed is processed. The fluid supply system includes: a circulation flow path that is connected to the fluid supply source and circulates the processing fluid; a supply flow path that connects the circulation flow path and the processing container and supplies the processing fluid from the circulation flow path into the processing container; a heating mechanism that is provided in the supply flow path and heats the processing fluid; and a return flow path that connects the circulation flow path and the supply flow path downstream of the heating mechanism and returns the processing fluid from the supply flow path to the circulation flow path.

Description

Fluid supply system, substrate processing apparatus, and substrate processing method

[0001] The present disclosure relates to a fluid supply system, a substrate processing apparatus, and a substrate processing method.

[0002] A technique for drying a substrate using a supercritical fluid is known. Patent Document 1 discloses a configuration for switching the temperature of the supercritical fluid supplied to the substrate.

[0003] Japanese Patent Application Laid-Open No. 2021-086857

[0004] The present disclosure provides a technique that can improve responsiveness when switching temperatures.

[0005] A fluid supply system according to one aspect of the present disclosure is a fluid supply system that supplies a processing fluid into a processing vessel in which a substrate having a liquid film formed thereon is processed, and includes a circulation flow path connected to a fluid supply source and circulating the processing fluid, a supply flow path that connects the circulation flow path to the processing vessel and supplies the processing fluid from the circulation flow path into the processing vessel, a heating mechanism provided in the supply flow path and heating the processing fluid, and a return flow path that connects the circulation flow path to the supply flow path downstream of the heating mechanism and returns the processing fluid from the supply flow path to the circulation flow path.

[0006] According to the present disclosure, it is possible to improve responsiveness when switching temperatures.

[0007] FIG. 1 is a diagram showing a substrate processing apparatus according to a first embodiment. FIG. 2 is a diagram showing an example of a heating mechanism. FIG. 3 is a flowchart showing a substrate processing method according to a first embodiment. FIG. 4 is a diagram showing pressure changes in a processing vessel in the substrate processing method of FIG. 3. FIG. 5 is a diagram (1) showing a substrate processing method according to a first embodiment. FIG. 6 is a diagram (2) showing a substrate processing method according to a first embodiment. FIG. 7 is a diagram (3) showing a substrate processing method according to a first embodiment. FIG. 8 is a diagram (4) showing a substrate processing method according to a first embodiment. FIG. 9 is a diagram (5) showing a substrate processing method according to a first embodiment. FIG. 10 is a diagram (6) showing a substrate processing method according to a first embodiment. FIG. 11 is a diagram (7) showing a substrate processing method according to a first embodiment. FIG. 12 is a diagram (8) showing a substrate processing method according to a first embodiment. FIG. 13 is a diagram (9) showing a substrate processing method according to a first embodiment. FIG. 14 is a diagram showing a substrate processing apparatus according to a second embodiment. FIG. 15 is a flowchart showing a substrate processing method according to a second embodiment. FIG. 16 is a diagram showing pressure changes in a processing vessel in the substrate processing method of FIG. 15 . FIG. 17 is a diagram (1) showing a substrate processing method according to a second embodiment. FIG. 18 is a diagram (2) showing a substrate processing method according to a second embodiment. FIG. 19 is a diagram (3) showing a substrate processing method according to a second embodiment. FIG. 20 is a diagram (4) showing a substrate processing method according to a second embodiment. FIG. 21 is a diagram (5) showing a substrate processing method according to a second embodiment. FIG. 22 is a diagram (6) showing a substrate processing method according to a second embodiment. FIG. 23 is a diagram (7) showing a substrate processing method according to a second embodiment. FIG. 24 is a diagram (8) showing a substrate processing method according to a second embodiment. FIG. 25 is a diagram (9) showing a substrate processing method according to a second embodiment. FIG. 26 is a diagram showing a substrate processing apparatus according to a first modified example. FIG. 27 is a diagram showing a substrate processing apparatus according to a second modified example.

[0008] Hereinafter, non-limiting exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. In all the accompanying drawings, the same or corresponding reference numerals are used to designate the same or corresponding members or components, and redundant descriptions will be omitted.

[0009] First Embodiment (Substrate Processing Apparatus) A substrate processing apparatus 10 according to a first embodiment will be described with reference to Figures 1 and 2. Figure 1 is a diagram showing the substrate processing apparatus 10 according to the first embodiment. Figure 2 is a diagram showing an example of a heating mechanism HE12.

[0010] The substrate processing apparatus 10 includes a processing section 11, a fluid supply system 12, a discharge section 13, and a control section 14.

[0011] The processing unit 11 has a processing vessel 111 and a holding unit 112. The processing vessel 111 is a vessel having a processing space formed therein that can accommodate a substrate W with a diameter of, for example, 300 mm. In the processing space, a substrate on which, for example, a liquid film is formed is processed. The substrate W may be, for example, a semiconductor wafer. The holding unit 112 is provided inside the processing vessel 111. The holding unit 112 holds the substrate W horizontally. The holding unit 112 is configured, for example, integrally with the processing vessel 111. The holding unit 112 may be a holding plate configured separately from the processing vessel 111. The processing unit 11 may have a temperature sensor and a pressure sensor.

[0012] The fluid supply system 12 includes a processing fluid supply source S11, an inert gas supply source S12, a circulation flow path L11, a first supply flow path L12, a return flow path L13, a depressurization flow path L14, and a second supply flow path L15.

[0013] The processing fluid supply source S11 is a supply source of a processing fluid. The processing fluid is, for example, carbon dioxide (CO ) in a gaseous or liquid state. ２ ) may be.

[0014] The inert gas supply source S12 is a supply source of an inert gas. The inert gas is, for example, nitrogen (N ２ ) gas.

[0015] The circulation flow path L11 is connected to a treatment fluid supply source S11. The circulation flow path L11 circulates the treatment fluid. A pump P11 and an on-off valve V11 are provided in the circulation flow path L11. The pump P11 sends the treatment fluid downstream of the circulation flow path L11. The on-off valve V11 is a valve that switches the flow of the treatment fluid on and off. When the on-off valve V11 is open, the treatment fluid is circulated within the circulation flow path L11, and when it is closed, the treatment fluid is not circulated within the circulation flow path L11.

[0016] An on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions on the circulation flow path L11.

[0017] The first supply flow path L12 connects the circulation flow path L11, which is downstream of the pump P11 and upstream of the on-off valve V11, to the processing vessel 111. The first supply flow path L12 supplies the processing fluid from the circulation flow path L11 into the processing vessel 111. The first supply flow path L12 is provided with a flow rate adjustment mechanism FC12, a heating mechanism HE12, a temperature sensor T12, an on-off valve V12, and a filter F12, in this order from upstream to downstream.

[0018] The flow rate adjustment mechanism FC12 is provided upstream of the heating mechanism HE12. The flow rate adjustment mechanism FC12 has on-off valves V121, V122, V123, and V124, and orifices OR122, OR123, and OR124.

[0019] The on-off valves V121, V122, V123, and V124 are connected in parallel to one another. The on-off valves V121, V122, V123, and V124 are valves that switch the flow of the processing fluid on and off. When open, the on-off valves V121, V122, V123, and V124 allow the processing fluid to flow to the downstream heating mechanism HE12, and when closed, they do not allow the processing fluid to flow to the downstream heating mechanism HE12.

[0020] The orifice OR122 is connected in series to the on-off valve V122. The orifice OR123 is connected in series to the on-off valve V123. The orifice OR124 is connected in series to the on-off valve V124. The orifices OR122, OR123, and OR124 serve to reduce the flow rate of the processing fluid flowing through the first supply flow path L12 and adjust the pressure. The orifices OR122, OR123, and OR124 can cause the processing fluid with adjusted pressure to flow to the downstream heating mechanism HE12.

[0021] The heating mechanism HE12 heats the processing fluid to a set temperature and supplies the processing fluid at the set temperature downstream. The set temperature is variable. The set temperature includes, for example, a first temperature and a second temperature. The first temperature is 15°C or higher and 100°C or lower, for example, 80°C. The second temperature is higher than the first temperature. The second temperature is 150°C or lower, for example, 120°C. As shown in FIG. 2 , the heating mechanism HE12 includes a spiral pipe HE121 and a heater HE122. The spiral pipe HE121 is spirally arranged around the heater HE122. The processing fluid flows through the spiral pipe HE121. The spiral pipe HE121 is made of, for example, stainless steel. The heater HE122 has a rod shape. The heater HE122 uses light irradiation to heat the spiral tube HE121 and the processing fluid flowing through the spiral tube HE121. When light heating is used, the heat capacity is small, resulting in good temperature response. The heater HE122 is a lamp heater using, for example, a halogen lamp or a xenon lamp. The heater HE122 may also be a heater using a laser or a light-emitting diode (LED).

[0022] The temperature sensor T12 is provided in the first supply flow path L12 downstream of the heating mechanism HE12 and upstream of the on-off valve V12. The temperature sensor T12 detects the temperature of the processing fluid flowing through the first supply flow path L12.

[0023] The on-off valve V12 is a valve that switches the flow of the processing fluid on and off. When the on-off valve V12 is open, the processing fluid flows to the downstream filter F12, and when it is closed, the processing fluid does not flow to the downstream filter F12.

[0024] The filter F12 filters the processing fluid flowing through the first supply passage L12 to remove foreign matter contained in the processing fluid, thereby suppressing the generation of particles on the surface of the substrate W during substrate processing using the processing fluid.

[0025] A line heater may be provided downstream of the heating mechanism HE12 in the first supply flow path L12. The line heater heats the first supply flow path L12 downstream of the heating mechanism. The line heater suppresses a temperature drop of the treatment fluid heated to a set temperature by the heating mechanism HE12 as it flows through the first supply flow path L12. Open / close valves, orifices, temperature sensors, and pressure sensors may also be provided at various positions in the first supply flow path L12.

[0026] The return flow path L13 connects the first supply flow path L12, which is downstream of the heating mechanism HE12 and upstream of the on-off valve V12, to the circulation flow path L11, which is downstream of the on-off valve V11. The return flow path L13 returns the processing fluid from the first supply flow path L12 to the circulation flow path L11. The return flow path L13 is provided with an on-off valve V13.

[0027] The on-off valve V13 is a valve that switches the flow of the treatment fluid on and off. When the on-off valve V13 is open, the treatment fluid flows through the downstream circulation flow path L11, and when it is closed, the treatment fluid does not flow through the downstream circulation flow path L11.

[0028] The depressurization flow path L14 branches off from the return flow path L13 downstream of the branch point from the first supply flow path L12 and upstream of the on-off valve V13. The depressurization flow path L14 discharges the treated fluid from the return flow path L13. The on-off valve V14 is provided in the depressurization flow path L14.

[0029] When the on-off valve V14 is open, it allows the processing fluid to flow into the downstream depressurization flow path L14, and when it is closed, it does not allow the processing fluid to flow into the downstream depressurization flow path L14.

[0030] The second supply flow path L15 is connected at its upstream end to the inert gas supply source S12 and at its downstream end to the first supply flow path L12 between the on-off valve V12 and the filter F12. The second supply flow path L15 supplies the inert gas to the first supply flow path L12 between the on-off valve V12 and the filter F12. A check valve C15 and an on-off valve V15 are provided in this order from upstream to downstream in the second supply flow path L15.

[0031] The check valve C15 prevents backflow of the processing fluid from the first supply flow path L12 to the inert gas supply source S12.

[0032] The on-off valve V15 is a valve that switches the flow of the inert gas on and off. When the on-off valve V15 is open, the inert gas flows into the downstream first supply flow path L12, and when the on-off valve V15 is closed, the inert gas does not flow into the downstream first supply flow path L12.

[0033] A heating mechanism, a line heater, an on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions on the second supply flow path L15.

[0034] The discharge unit 13 has a discharge flow path L18. The discharge flow path L18 is connected to the processing vessel 111. A pressure sensor P18, a back pressure valve BV18, and an on-off valve V18 are provided in this order from upstream to downstream in the discharge flow path L18.

[0035] The pressure sensor P18 detects the pressure of the fluid flowing through the discharge flow path L18 immediately after the processing vessel 111. In this way, the pressure inside the processing vessel 111 can be detected.

[0036] When the primary pressure of the discharge flow path L18 exceeds a set pressure, the back pressure valve BV18 ​​adjusts the valve opening to allow the fluid to flow to the secondary side, thereby maintaining the primary pressure at the set pressure. For example, the set pressure of the back pressure valve BV18 ​​is adjusted by the control unit 14.

[0037] The on-off valve V18 is a valve that switches the flow of fluid on and off. When the on-off valve V18 is open, the fluid flows into the downstream discharge flow path L18, and when it is closed, the fluid does not flow into the downstream discharge flow path L18.

[0038] A line heater may be provided in the discharge flow path L18. The line heater heats the discharge flow path L18. An on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions in the discharge flow path L18.

[0039] The control unit 14 is, for example, a computer, and includes an arithmetic unit 141 and a storage unit 142. The storage unit 142 stores programs for controlling various processes executed in the substrate processing apparatus 10. The arithmetic unit 141 controls the operation of the substrate processing apparatus 10 by reading and executing the programs stored in the storage unit 142. The programs may be recorded on a computer-readable storage medium and installed from the storage medium into the storage unit 142 of the control unit 14. Examples of computer-readable storage media include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), and a memory card.

[0040] The control unit 14 receives measurement signals from various sensors (such as the temperature sensor T12 and the pressure sensor P18) and transmits control signals to various functional elements. The control signals include, for example, open / close signals for the on-off valves V11, V12, V121, V122, V123, V124, V13, V14, V15, and V18, a set pressure signal for the back pressure valve BV18, a set temperature signal for the heating mechanism HE12, and a set temperature signal for the line heater.

[0041] For example, the control unit 14 may control the heating mechanism HE12 to raise the temperature of the processing fluid from the first temperature to the second temperature while supplying the processing fluid into the processing vessel 111. The heating mechanism HE12 using optical heating has a small heat capacity and therefore good temperature responsiveness, so that the processing fluid can be raised from the first temperature to the second temperature in a short time.

[0042] For example, the control unit 14 may circulate the processing fluid between the circulation flow path L11, the first supply flow path L12, and the return flow path L13 while discharging the processing fluid from the processing vessel 111 through the discharge flow path L18 without supplying the processing fluid into the processing vessel 111. In this case, the discharge of the processing fluid from the processing vessel 111 and the preparation of the processing fluid to be used in processing the next substrate W can be performed in parallel. This allows the processing time in consecutive processing to be shortened.

[0043] For example, the control unit 14 may circulate the processing fluid between the circulation flow path L11, the first supply flow path L12, and the return flow path L13 until the temperature of the processing fluid detected by the temperature sensor T12 reaches the target temperature. In this case, the processing fluid at the target temperature is supplied into the processing vessel 111 immediately after the on-off valve V12 is opened. This makes it possible to suppress temperature fluctuations immediately after the processing fluid is supplied.

[0044] For example, the control unit 14 may control the on-off valve V14 to discharge the processing fluid in the return flow path L13 through the depressurization flow path L14 before supplying the processing fluid into the processing vessel 111. In this case, the high-pressure processing fluid is prevented from being supplied into the processing vessel 111 immediately after the on-off valve V12 is opened. This prevents the processing fluid from being supplied to the substrate W at a high speed, thereby preventing pattern collapse.

[0045] For example, the control unit 14 may set the supply flow rate of the processing fluid supplied into the processing vessel 111 to a first flow rate until the pressure inside the processing vessel 111 reaches a first pressure, thereby increasing the pressure inside the processing vessel 111. Alternatively, once the pressure inside the processing vessel 111 reaches the first pressure, the control unit 14 may set the supply flow rate to a second flow rate that is greater than the first flow rate, thereby further increasing the pressure inside the processing vessel 111. In this case, the processing fluid is prevented from being supplied to the substrate W at a high speed in the initial stage, thereby preventing pattern collapse.

[0046] As described above, the substrate processing apparatus 10 according to the first embodiment includes the circulation flow path L11, the first supply flow path L12 in which the heating mechanism HE12 is provided, and the return flow path L13. The return flow path L13 connects the circulation flow path L11 to the first supply flow path L12 downstream of the heating mechanism HE12. In this case, the processing fluid flowing through the first supply flow path L12 is returned to the circulation flow path L11 via the return flow path L13, thereby circulating the processing fluid between the circulation flow path L11, the first supply flow path L12, and the return flow path L13. This allows the temperature of the first supply flow path L12 to be changed in a short time before the processing fluid is supplied into the processing vessel 111. In other words, the responsiveness during temperature switching can be improved.

[0047] 3 to 13, a substrate processing method executed using the substrate processing apparatus 10 will be described. The substrate processing method described below is automatically executed under the control of the control unit 14 based on the processing recipe and control program stored in the storage unit 142.

[0048] Fig. 3 is a flowchart showing a substrate processing method according to the first embodiment. Fig. 4 is a diagram showing pressure changes in the processing vessel 111 in the substrate processing method of Fig. 3. Figs. 5 to 13 are diagrams showing the substrate processing method according to the first embodiment. In Figs. 5 to 13, on-off valves in an open state are shown in black, and on-off valves in a closed state are shown in white. In Figs. 5 to 13, flow paths through which fluids flow are shown by thick solid lines.

[0049] 3 , the substrate processing method according to the first embodiment includes a waiting step ST11, a pressure increase step ST12, a circulation step ST13, and a pressure reduction step ST14. The following description will be given assuming that the substrate W is loaded into the processing container 111 before the waiting step ST11. The substrate W is subjected to a cleaning process, and is placed on the holder 112 with the recesses of the pattern on the surface filled with isopropyl alcohol (IPA).

[0050] 5 , the set temperature of the heating mechanism HE12 is set to a first temperature, for example, 80° C., and the on-off valves V121, V13, V15, and V18 are opened, while the on-off valves V11, V12, V122, V123, V124, and V14 are closed. As a result, the processing fluid from the processing fluid supply source S11 circulates through the circulation flow path L11, the first supply flow path L12, the return flow path L13, and the circulation flow path L11 in this order. The processing fluid is heated to the first temperature by the heating mechanism HE12 in the first supply flow path L12. As the processing fluid circulates through the circulation flow path L11, the first supply flow path L12, the return flow path L13, and the circulation flow path L11 in this order, each flow path approaches the first temperature. In the standby process ST11, the processing fluid may be circulated between the circulation flow path L11, the first supply flow path L12, and the return flow path L13 until the temperature of the processing fluid detected by the temperature sensor T12 reaches the first temperature. In this case, the processing fluid at the first temperature is supplied into the processing vessel 111 immediately after the on-off valve V12 is opened. This suppresses temperature fluctuations immediately after the processing fluid is supplied. In addition, the inert gas from the inert gas supply source S12 is supplied into the processing vessel 111 through the second supply flow path L15 and the first supply flow path L12 and is discharged through the discharge flow path L18.

[0051] Next, as shown in FIG. 6 , the on-off valves V13 and V121 are switched from the open state to the closed state, and the on-off valves V11 and V14 are switched from the closed state to the open state. This stops the circulation of the processing fluid between the circulation flow path L11, the first supply flow path L12, and the return flow path L13. Furthermore, the processing fluid in the first supply flow path L12 between the flow rate adjustment mechanism FC12 and the on-off valve V12 and the processing fluid in the return flow path L13 between the on-off valve V12 and the on-off valve V13 are discharged through the depressurization flow path L14. This reduces the pressure in the first supply flow path L12 between the flow rate adjustment mechanism FC12 and the on-off valve V12 and the pressure in the return flow path L13 between the on-off valve V12 and the on-off valve V13. In this case, high-pressure processing fluid is prevented from being supplied into the processing vessel 111 immediately after the on-off valve V12 is opened. This prevents the processing fluid from being supplied to the substrate W at high speed, thereby suppressing pattern collapse. Furthermore, the on-off valve V15 is switched from an open state to a closed state, whereby the inert gas in the processing vessel 111 is discharged through the discharge flow path L18.

[0052] Next, as shown in FIG. 7, the on-off valve V18 is switched from the open state to the closed state, and the on-off valve V12 is switched from the closed state to the open state.

[0053] <Pressure Increase Step ST12> The pressure increase step ST12 is performed after the standby step ST11. In the pressure increase step ST12, first, the pressure inside the processing vessel 111 is increased by supplying a processing fluid at a first flow rate and a first temperature (first pressure increase step). Next, the pressure inside the processing vessel 111 is increased by supplying a processing fluid at a second flow rate and a first temperature (second pressure increase step). Next, the pressure inside the processing vessel 111 is increased by supplying a processing fluid at a third flow rate and a first temperature (third pressure increase step). Next, the pressure inside the processing vessel 111 is increased by supplying a processing fluid at a third flow rate and a second temperature, for example, 120°C (fourth pressure increase step). The magnitude relationship between the first flow rate, the second flow rate, and the third flow rate is first flow rate < second flow rate < third flow rate. The second temperature is higher than the first temperature.

[0054] In the first pressurization step, as shown in FIG. 8 , the on-off valve V122 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S11 is supplied into the processing vessel 111 via the circulation flow path L11 and the first supply flow path L12. At this time, the processing fluid is adjusted to a first flow rate by passing through the orifice OR122, and is adjusted to a first temperature by passing through the heating mechanism HE12. Therefore, the processing fluid at the first flow rate and the first temperature is supplied into the processing vessel 111. In the first pressurization step, because the on-off valve V18 is closed, the processing fluid does not flow out of the processing vessel 111. Therefore, the pressure inside the processing vessel 111 gradually increases. As a result, pattern collapse can be suppressed.

[0055] During the first pressurization step, the pressure inside the processing vessel 111 is detected by the pressure sensor P18, and the pressure is continued to be increased at the first flow rate until the pressure inside the processing vessel 111 reaches a first pressure Y1 (see FIG. 4). When the pressure inside the processing vessel 111 reaches the first pressure Y1, the first pressurization step is terminated and the process proceeds to a second pressurization step.

[0056] In the second pressurization step, as shown in FIG. 9 , the on-off valve V123 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S11 is adjusted to a second flow rate by passing through the orifices OR122 and OR123, and is adjusted to a first temperature by passing through the heating mechanism HE12. Therefore, the processing fluid at the second flow rate and the first temperature is supplied into the processing vessel 111. In the second pressurization step, the on-off valve V18 is closed, so the processing fluid does not flow out of the processing vessel 111. Therefore, the pressure in the processing vessel 111 gradually increases. In the second pressurization step, the processing fluid is pressurized at a larger flow rate than in the first pressurization step, so the pressurization speed can be increased.

[0057] During the second pressurization step, the pressure inside the processing vessel 111 is detected by the pressure sensor P18, and the pressure is continued to be increased at the second flow rate until the pressure inside the processing vessel 111 reaches a second pressure Y2 (see FIG. 4). When the pressure inside the processing vessel 111 reaches the second pressure Y2, the second pressurization step is terminated and the process proceeds to a third pressurization step.

[0058] In the third pressurization step, as shown in FIG. 10 , the on-off valve V124 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S11 is adjusted to a third flow rate by passing through the orifices OR122, OR123, and OR124, and is adjusted to a first temperature by passing through the heating mechanism HE12. Therefore, the processing fluid at the third flow rate and the first temperature is supplied into the processing vessel 111. In the third pressurization step, the on-off valve V18 is closed, so the processing fluid does not flow out of the processing vessel 111. Therefore, the pressure in the processing vessel 111 gradually increases. In the third pressurization step, the processing fluid is pressurized at a larger flow rate than in the second pressurization step, and therefore the pressurization speed can be further increased.

[0059] When the pressure is increased at the third flow rate, the pressure of the processing fluid supplied into the processing vessel 111 is lower than the critical pressure. Therefore, the processing fluid is supplied in a gaseous state into the processing vessel 111. Thereafter, as the processing vessel 111 is filled with the processing fluid, the pressure inside the processing vessel 111 increases. When the pressure inside the processing vessel 111 exceeds the critical pressure, the processing fluid present in the processing vessel 111 becomes supercritical.

[0060] During the third pressurization step, the pressure inside the processing vessel 111 is detected by the pressure sensor P18, and the pressure is continued to be increased at the third flow rate until the pressure inside the processing vessel 111 reaches a third pressure Y3 (see FIG. 4). When the pressure inside the processing vessel 111 reaches the third pressure Y3, the third pressurization step is terminated and the process proceeds to a fourth pressurization step.

[0061] In the fourth pressurization step, as shown in FIG. 11 , the set temperature of the heating mechanism HE12 is changed from the first temperature to the second temperature. As a result, the processing fluid from the processing fluid supply source S11 is adjusted to the second temperature by passing through the heating mechanism HE12. Therefore, the processing fluid at the third flow rate and the second temperature is supplied into the processing vessel 111. In this manner, while the processing fluid is being supplied into the processing vessel 111, the heating mechanism HE12 is controlled to raise the temperature of the processing fluid from the first temperature to the second temperature. The heating mechanism HE12, which uses optical heating, has a small heat capacity and therefore good temperature responsiveness. Therefore, the processing fluid can be raised from the first temperature to the second temperature in a short time. In the fourth pressurization step, the on-off valve V18 is closed, so the processing fluid does not flow out of the processing vessel 111. Therefore, the pressure inside the processing vessel 111 gradually increases.

[0062] During the fourth pressurization step, the pressure inside the processing vessel 111 is detected by the pressure sensor P18, and the fourth pressurization step is continued until the pressure inside the processing vessel 111 reaches a fourth pressure Y4 (see FIG. 4). When the pressure inside the processing vessel 111 reaches the fourth pressure Y4, the fourth pressurization step is terminated and the process proceeds to the circulation step.

[0063] As described above, in the pressure increasing step, the pressure increasing speed is increased in the order of the first pressure increasing step, the second pressure increasing step, and the third pressure increasing step. In this case, the supply of the processing fluid to the substrate W at a high speed is suppressed in the initial stage, and pattern collapse can be suppressed.

[0064] <Circulating Step ST13> The circulating step ST13 is performed after the pressurization step ST12. In the circulating step ST13, a processing fluid at a third flow rate and a second temperature is supplied from the processing fluid supply source S11 into the processing vessel 111, and the IPA is replaced with the processing fluid in the recesses of the pattern on the substrate W in the processing vessel 111. Specifically, as shown in FIG. 12 , the on-off valve V18 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S11 is supplied into the processing vessel 111 via the circulation flow path L11 and the first supply flow path L12, and is also discharged from the processing vessel 111 via the discharge flow path L18. As a result, the pressure in the processing vessel 111 is maintained at the fourth pressure Y4 (see FIG. 4 ). By performing the circulating step ST13, the replacement of the IPA with the processing fluid in the recesses of the pattern on the substrate W is promoted.

[0065] When the replacement of the IPA with the processing fluid in the recesses of the pattern is completed, the flowing step ST13 is finished and the process proceeds to the depressurizing step ST14.

[0066] <Depressurization Step ST14> The depressurization step ST14 is performed after the flow step ST13. In the depressurization step ST14, the processing fluid is discharged from the processing vessel 111. Specifically, as shown in FIG. 13 , the on-off valve V12 is switched from an open state to a closed state. As a result, the processing fluid remaining in the processing vessel 111 is discharged through the discharge flow path L18. When the pressure in the processing vessel 111 becomes lower than the critical pressure of the processing fluid by the depressurization step ST14, the processing fluid in the supercritical state is vaporized and escapes from the recesses of the pattern. This completes the drying process for one substrate W.

[0067] 13 , in the depressurization step ST14, the set temperature of the heating mechanism HE12 is changed from the second temperature to the first temperature, the on-off valves V11, V122, V123, and V124 are switched from an open state to a closed state, and the on-off valves V121 and V13 are switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S11 circulates between the circulation flow path L11, the first supply flow path L12, and the return flow path L13, and the temperature is reduced from the second temperature to the first temperature. In this case, the processing fluid can be discharged from the processing vessel 111 and the processing fluid to be used in processing the next substrate W can be prepared in parallel. This reduces the processing time in the continuous processing.

[0068] After the depressurization step ST14, the process proceeds to the standby step ST11. The processed substrate W is unloaded from the processing vessel 111, for example, after the process proceeds to the standby step ST11. Specifically, after the depressurization step ST14, supply of inert gas into the processing vessel 111 begins via the second supply flow path L15. Next, the substrate W is unloaded from the processing vessel 111 while the inert gas is being supplied into the processing vessel 111. Even after the substrate W is unloaded from the processing vessel 111, the supply of inert gas into the processing vessel 111 continues. In this way, when the substrate W is unloaded from the processing vessel 111 while the inert gas is being supplied into the processing vessel 111, the inside of the processing vessel 111 becomes positive pressure, and a gas flow is formed from the inside to the outside of the processing vessel 111 when the processing vessel 111 is opened. Therefore, residue in the processing vessel 111 can be discharged and removed to the outside of the processing vessel 111. However, when the substrate W is unloaded from the processing vessel 111, the supply of the inert gas into the processing vessel 111 may be stopped.

[0069] In the substrate processing method according to the first embodiment described above, the heating mechanism HE12 is controlled in the pressure increase step ST12 to increase the temperature of the processing fluid from the first temperature to the second temperature, but this is not limiting. For example, the heating mechanism HE12 may be controlled in the flow step ST13 to increase the temperature of the processing fluid from the first temperature to the second temperature.

[0070] Second Embodiment (Substrate Processing Apparatus) A substrate processing apparatus 20 according to a second embodiment will be described with reference to Fig. 14. Fig. 14 is a diagram showing the substrate processing apparatus 20 according to the second embodiment. As shown in Fig. 14, the substrate processing apparatus 20 according to the second embodiment differs from the substrate processing apparatus 10 according to the first embodiment in that a flow rate adjustment mechanism FC22 is provided downstream of a heating mechanism HE22.

[0071] The substrate processing apparatus 20 includes a processing section 21 , a fluid supply system 22 , a discharge section 23 , and a control section 24 .

[0072] The processing unit 21 includes a processing vessel 211 and a holding unit 212. The processing vessel 211 and the holding unit 212 may be similar to the processing vessel 111 and the holding unit 112, respectively. The processing unit 21 may include a temperature sensor and a pressure sensor.

[0073] The fluid supply system 22 has a processing fluid supply source S21, an inert gas supply source S22, a circulation flow path L21, a first supply flow path L22, a return flow path L23, a depressurization flow path L24, and a second supply flow path L25.

[0074] The processing fluid supply source S21 is a supply source of a processing fluid. The processing fluid is, for example, carbon dioxide (CO ) in a gaseous or liquid state. ２ ) may be.

[0075] The inert gas supply source S22 is a supply source of an inert gas. The inert gas is, for example, nitrogen (N ２ ) gas.

[0076] The circulation flow path L21 is connected to a treatment fluid supply source S21. The circulation flow path L21 circulates the treatment fluid. A pump P21 and an on-off valve V21 are provided in the circulation flow path L21. The pump P21 and the on-off valve V21 may be similar to the pump P11 and the on-off valve V11, respectively.

[0077] An on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions in the circulation flow path L21.

[0078] The first supply flow path L22 connects the circulation flow path L21, which is downstream of the pump P21 and upstream of the on-off valve V21, to the processing vessel 211. The first supply flow path L22 supplies the processing fluid from the circulation flow path L21 into the processing vessel 211. The first supply flow path L22 is provided with a heating mechanism HE22, a temperature sensor T22, a flow rate adjustment mechanism FC22, and a filter F22, in this order from upstream to downstream.

[0079] The heating mechanism HE22 heats the processing fluid to a set temperature and supplies the processing fluid at the set temperature downstream. The set temperature is variable. The set temperature includes, for example, a first temperature and a second temperature. The first temperature is equal to or higher than 15°C and equal to or lower than 100°C, for example, 80°C. The second temperature is higher than the first temperature. The second temperature is equal to or lower than 150°C, for example, 120°C. The heating mechanism HE22 may be similar to the heating mechanism HE12.

[0080] The temperature sensor T22 is provided in the first supply flow path L22 downstream of the heating mechanism HE22 and upstream of the flow rate adjustment mechanism FC22. The temperature sensor T22 detects the temperature of the processing fluid flowing through the first supply flow path L22.

[0081] The flow rate adjustment mechanism FC22 is provided downstream of the heating mechanism HE22. The flow rate adjustment mechanism FC22 has on-off valves V222, V223, and V224 and orifices OR222, OR223, and OR224. The on-off valves V222, V223, and V224 and the orifices OR222, OR223, and OR224 may be similar to the on-off valves V122, V123, and V124 and the orifices OR122, OR123, and OR124, respectively.

[0082] Filter F22 may be similar to filter F12.

[0083] A line heater may be provided downstream of the heating mechanism HE22 in the first supply flow path L22. The line heater heats the first supply flow path L22 downstream of the heating mechanism. The line heater suppresses a temperature drop of the treatment fluid heated to a set temperature by the heating mechanism HE22 as it flows through the first supply flow path L22. Open / close valves, orifices, temperature sensors, and pressure sensors may also be provided at various positions in the first supply flow path L22.

[0084] The return flow path L23 connects the first supply flow path L22, which is downstream of the heating mechanism HE22 and upstream of the flow rate control mechanism FC22, to the circulation flow path L21, which is downstream of the on-off valve V21. The return flow path L23 returns the processing fluid from the first supply flow path L22 to the circulation flow path L21. The return flow path L23 is provided with an on-off valve V23. The on-off valve V23 may be the same as the on-off valve V13.

[0085] The depressurization flow path L24 branches off from the return flow path L23 downstream of the branch point from the first supply flow path L22 and upstream of the on-off valve V23. The depressurization flow path L24 discharges the treatment fluid from the return flow path L23. The depressurization flow path L24 is provided with an on-off valve V24. The on-off valve V24 may be the same as the on-off valve V14.

[0086] The second supply flow path L25 is connected at its upstream end to the inert gas supply source S22 and at its downstream end to the first supply flow path L22 between the temperature sensor T22 and the filter F22. The second supply flow path L25 supplies the inert gas to the first supply flow path L22 between the temperature sensor T22 and the filter F22. A check valve C25 and an on-off valve V25 are provided in this order from upstream to downstream in the second supply flow path L25. The check valve C25 and the on-off valve V25 may be similar to the check valve C15 and the on-off valve V15, respectively.

[0087] A heating mechanism, a line heater, an on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions on the second supply flow path L25.

[0088] The discharge unit 23 has a discharge flow path L28. The discharge flow path L28 is connected to the processing vessel 211. A pressure sensor P28, a back pressure valve BV28, and an on-off valve V28 are provided in this order from upstream to downstream in the discharge flow path L28. The pressure sensor P28, the back pressure valve BV28, and the on-off valve V28 may be similar to the pressure sensor P18, the back pressure valve BV18, and the on-off valve V18, respectively.

[0089] A line heater may be provided in the discharge flow path L28. The line heater heats the discharge flow path L28. An on-off valve, an orifice, a temperature sensor, and a pressure sensor may further be provided at various positions in the discharge flow path L28.

[0090] The control unit 24 is, for example, a computer, and includes a calculation unit 241 and a storage unit 242. The calculation unit 241 and the storage unit 242 may be similar to the calculation unit 141 and the storage unit 142, respectively.

[0091] The control unit 24 receives measurement signals from various sensors (such as the temperature sensor T22 and the pressure sensor P28) and transmits control signals to various functional elements. The control signals include, for example, open / close signals for the on-off valves V21, V222, V223, V224, V23, V24, V25, and V28, a set pressure signal for the back pressure valve BV28, a set temperature signal for the heating mechanism HE22, and a set temperature signal for the line heater.

[0092] For example, the control unit 24 may control the heating mechanism HE22 to raise the temperature of the processing fluid from the first temperature to the second temperature while supplying the processing fluid into the processing vessel 211. The heating mechanism HE22 using optical heating has a small heat capacity and therefore good temperature responsiveness, so that the processing fluid can be raised from the first temperature to the second temperature in a short time.

[0093] For example, the control unit 24 may circulate the processing fluid between the circulation flow path L21, the first supply flow path L22, and the return flow path L23 while discharging the processing fluid from the processing vessel 211 through the discharge flow path L28 without supplying the processing fluid into the processing vessel 211. In this case, the discharge of the processing fluid from the processing vessel 211 and the preparation of the processing fluid to be used in processing the next substrate W can be performed in parallel. This allows the processing time in consecutive processing to be shortened.

[0094] For example, the control unit 24 may circulate the processing fluid between the circulation flow path L21, the first supply flow path L22, and the return flow path L23 until the temperature of the processing fluid detected by the temperature sensor T22 reaches the target temperature. In this case, the processing fluid at the target temperature is supplied into the processing vessel 211 immediately after the on-off valve V12 is opened. This makes it possible to suppress temperature fluctuations immediately after the processing fluid is supplied.

[0095] For example, the control unit 24 may set the supply flow rate of the processing fluid supplied into the processing vessel 211 to a first flow rate until the pressure inside the processing vessel 211 reaches a first pressure, thereby increasing the pressure inside the processing vessel 211. Furthermore, once the pressure inside the processing vessel 211 reaches the first pressure, the control unit 24 may set the supply flow rate to a second flow rate that is greater than the first flow rate, thereby further increasing the pressure inside the processing vessel 211. In this case, the processing fluid is prevented from being supplied to the substrate W at a high speed in the initial stage, thereby preventing pattern collapse.

[0096] As described above, the substrate processing apparatus 20 according to the second embodiment includes the circulation flow path L21, the first supply flow path L22 in which the heating mechanism HE22 is provided, and the return flow path L23. The return flow path L23 connects the circulation flow path L21 to the first supply flow path L22 downstream of the heating mechanism HE22. In this case, the processing fluid flowing through the first supply flow path L22 is returned to the circulation flow path L21 via the return flow path L23, thereby circulating the processing fluid between the circulation flow path L21, the first supply flow path L22, and the return flow path L23. This allows the temperature of the first supply flow path L22 to be changed in a short time before the processing fluid is supplied into the processing vessel 211. In other words, the responsiveness during temperature switching can be improved.

[0097] 15 to 25 , a substrate processing method executed using the substrate processing apparatus 20 will be described. The substrate processing method described below is automatically executed under the control of the control unit 24 based on the processing recipe and control program stored in the storage unit 242.

[0098] Fig. 15 is a flowchart showing a substrate processing method according to the second embodiment. Fig. 16 is a diagram showing pressure changes in the processing vessel 211 in the substrate processing method of Fig. 15. Figs. 17 to 25 are diagrams showing a substrate processing method according to the second embodiment. In Figs. 17 to 25, on-off valves in an open state are shown in black, and on-off valves in a closed state are shown in white. In Figs. 17 to 25, flow paths through which fluids flow are shown by thick solid lines.

[0099] 15 , the substrate processing method according to the second embodiment includes a waiting step ST21, a pressure increase step ST22, a circulation step ST23, and a pressure decrease step ST24. The following description will be given assuming that the substrate W is loaded into the processing container 211 before the waiting step ST21. The substrate W is subjected to a cleaning process, and is placed on the holder 212 with the recesses of the pattern on the surface filled with IPA.

[0100] 17 , the set temperature of the heating mechanism HE22 is set to a first temperature, for example, 80° C., and the on-off valves V23, V25, and V28 are opened, while the on-off valves V21, V222, V223, V224, and V24 are closed. As a result, the processing fluid from the processing fluid supply source S21 circulates through the circulation flow path L21, the first supply flow path L22, the return flow path L23, and the circulation flow path L21 in this order. The processing fluid is heated to the first temperature by the heating mechanism HE22 in the first supply flow path L22. As the processing fluid circulates through the circulation flow path L21, the first supply flow path L22, the return flow path L23, and the circulation flow path L21 in this order, each flow path approaches the first temperature. In the standby process ST21, the processing fluid may be circulated between the circulation flow path L21, the first supply flow path L22, and the return flow path L23 until the temperature of the processing fluid detected by the temperature sensor T22 reaches the first temperature. In this case, the processing fluid at the first temperature is supplied into the processing vessel 211 immediately after the on-off valve V222 is opened. This suppresses temperature fluctuations immediately after the processing fluid is supplied. In addition, the inert gas from the inert gas supply source S22 is supplied into the processing vessel 211 through the second supply flow path L25 and the first supply flow path L22 and is discharged through the discharge flow path L28.

[0101] 18, the on-off valve V23 is switched from an open state to a closed state, and the on-off valve V21 is switched from an open state to a closed state. This stops the circulation of the processing fluid between the circulation flow path L21, the first supply flow path L22, and the return flow path L23. In addition, the on-off valve V25 is switched from an open state to a closed state. This causes the inert gas in the processing vessel 111 to be discharged through the discharge flow path L18.

[0102] Next, as shown in FIG. 19, the on-off valve V28 is switched from the open state to the closed state.

[0103] <Pressure Increase Step ST22> The pressure increase step ST22 is performed after the standby step ST21. In the pressure increase step ST22, first, the pressure inside the processing vessel 211 is increased by supplying a processing fluid at a first flow rate and a first temperature (first pressure increase step). Next, the pressure inside the processing vessel 211 is increased by supplying a processing fluid at a second flow rate and a first temperature (second pressure increase step). Next, the pressure inside the processing vessel 211 is increased by supplying a processing fluid at a third flow rate and a first temperature (third pressure increase step). Next, the pressure inside the processing vessel 211 is increased by supplying a processing fluid at a third flow rate and a second temperature, for example, 120°C (fourth pressure increase step). The magnitude relationship between the first flow rate, the second flow rate, and the third flow rate is first flow rate < second flow rate < third flow rate. The second temperature is higher than the first temperature.

[0104] In the first pressurization step, as shown in FIG. 20 , the on-off valve V222 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S21 is supplied into the processing vessel 111 via the circulation flow path L21 and the first supply flow path L22. At this time, the processing fluid is adjusted to a first temperature by passing through the heating mechanism HE22, and is adjusted to a first flow rate by passing through the orifice OR222. Therefore, the processing fluid at the first flow rate and the first temperature is supplied into the processing vessel 211. In the first pressurization step, the on-off valve V28 is closed, so the processing fluid does not flow out of the processing vessel 211. Therefore, the pressure inside the processing vessel 211 gradually increases. As a result, pattern collapse can be suppressed.

[0105] During the first pressurization step, the pressure inside the processing vessel 211 is detected by the pressure sensor P28, and the pressure is continued to be increased at the first flow rate until the pressure inside the processing vessel 211 reaches a first pressure Y1 (see FIG. 16 ). When the pressure inside the processing vessel 211 reaches the first pressure Y1, the first pressurization step is terminated and the process proceeds to a second pressurization step.

[0106] In the second pressurization step, as shown in FIG. 21 , the on-off valve V223 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S21 is adjusted to a first temperature by passing through the heating mechanism HE22, and is adjusted to a second flow rate by passing through the orifices OR222 and OR223. Therefore, the processing fluid at the second flow rate and the first temperature is supplied into the processing vessel 211. In the second pressurization step, the on-off valve V28 is closed, so the processing fluid does not flow out of the processing vessel 211. Therefore, the pressure in the processing vessel 211 gradually increases. In the second pressurization step, the processing fluid is pressurized at a larger flow rate than in the first pressurization step, so the pressurization speed can be increased.

[0107] During the second pressurization step, the pressure inside the processing vessel 211 is detected by the pressure sensor P28, and the pressure is continued to be increased at the second flow rate until the pressure inside the processing vessel 211 reaches a second pressure Y2 (see FIG. 16 ). When the pressure inside the processing vessel 211 reaches the second pressure Y2, the second pressurization step is terminated and the process proceeds to a third pressurization step.

[0108] In the third pressurization step, as shown in FIG. 22 , the on-off valve V224 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S21 is adjusted to a first temperature by passing through the heating mechanism HE22, and is adjusted to a third flow rate by passing through the orifices OR222, OR223, and OR224. Therefore, the processing fluid at the third flow rate and the first temperature is supplied into the processing vessel 211. In the third pressurization step, the on-off valve V28 is closed, so the processing fluid does not flow out of the processing vessel 211. Therefore, the pressure in the processing vessel 211 gradually increases. In the third pressurization step, the processing fluid is pressurized at a larger flow rate than in the second pressurization step, and therefore the pressurization speed can be further increased.

[0109] When the pressure is increased at the third flow rate, the pressure of the processing fluid supplied into the processing vessel 211 is lower than the critical pressure. Therefore, the processing fluid is supplied in a gaseous state into the processing vessel 211. Thereafter, as the processing vessel 211 is filled with the processing fluid, the pressure inside the processing vessel 211 increases. When the pressure inside the processing vessel 211 exceeds the critical pressure, the processing fluid present in the processing vessel 211 becomes supercritical.

[0110] During the third pressurization step, the pressure inside the processing vessel 211 is detected by the pressure sensor P28, and the pressure is continued to be increased at the third flow rate until the pressure inside the processing vessel 211 reaches a third pressure Y3 (see FIG. 16 ). When the pressure inside the processing vessel 211 reaches the third pressure Y3, the third pressurization step is terminated, and the process proceeds to a fourth pressurization step.

[0111] In the fourth pressurization step, as shown in FIG. 23 , the set temperature of the heating mechanism HE22 is changed from the first temperature to the second temperature. As a result, the processing fluid from the processing fluid supply source S21 is adjusted to the second temperature by passing through the heating mechanism HE22. Therefore, the processing fluid at the third flow rate and the second temperature is supplied into the processing vessel 211. In this manner, while the processing fluid is being supplied into the processing vessel 211, the heating mechanism HE22 is controlled to raise the temperature of the processing fluid from the first temperature to the second temperature. The heating mechanism HE22, which uses optical heating, has a small heat capacity and therefore good temperature responsiveness. Therefore, the processing fluid can be raised from the first temperature to the second temperature in a short time. In the fourth pressurization step, the on-off valve V28 is closed, so the processing fluid does not flow out of the processing vessel 211. Therefore, the pressure inside the processing vessel 211 gradually increases.

[0112] During the fourth pressurization step, the pressure inside the processing vessel 211 is detected by the pressure sensor P28, and the fourth pressurization step is continued until the pressure inside the processing vessel 211 reaches a fourth pressure Y4 (see FIG. 16 ). When the pressure inside the processing vessel 211 reaches the fourth pressure Y4, the fourth pressurization step is terminated and the process proceeds to the circulation step.

[0113] As described above, in the pressure increasing step, the pressure increasing speed is increased in the order of the first pressure increasing step, the second pressure increasing step, and the third pressure increasing step. In this case, the supply of the processing fluid to the substrate W at a high speed is suppressed in the initial stage, and pattern collapse can be suppressed.

[0114] <Circulating Step ST23> The circulating step ST23 is performed after the pressurization step ST22. In the circulating step ST23, a processing fluid at a third flow rate and a second temperature is supplied from the processing fluid supply source S21 into the processing vessel 211, and the IPA is replaced with the processing fluid in the recesses of the pattern on the substrate W in the processing vessel 211. Specifically, as shown in FIG. 24 , the on-off valve V28 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S21 is supplied into the processing vessel 211 via the circulation flow path L21 and the first supply flow path L22, and is also discharged from the processing vessel 211 via the discharge flow path L28. Therefore, the pressure in the processing vessel 211 is maintained at the fourth pressure Y4 (see FIG. 16 ). By performing the circulating step ST23, the replacement of the IPA with the processing fluid in the recesses of the pattern on the substrate W is promoted.

[0115] When the replacement of the IPA with the processing fluid in the recesses of the pattern is completed, the flowing step ST23 is completed and the process moves to the depressurizing step ST24.

[0116] <Depressurization Step ST24> The depressurization step ST24 is performed after the flowing step ST23. In the depressurization step ST24, the processing fluid is discharged from the processing vessel 211. Specifically, as shown in FIG. 25 , the on-off valves V222, V223, and V224 are switched from an open state to a closed state. As a result, the processing fluid remaining in the processing vessel 211 is discharged through the discharge flow path L28. When the pressure in the processing vessel 211 becomes lower than the critical pressure of the processing fluid by the depressurization step ST24, the processing fluid in a supercritical state is vaporized and escapes from the recesses of the pattern. This completes the drying process for one substrate W.

[0117] 25 , in the depressurization step ST24, the set temperature of the heating mechanism HE22 is changed from the second temperature to the first temperature, the on-off valve V21 is switched from an open state to a closed state, and the on-off valve V23 is switched from a closed state to an open state. As a result, the processing fluid from the processing fluid supply source S21 circulates between the circulation flow path L21, the first supply flow path L22, and the return flow path L23, and the temperature is reduced from the second temperature to the first temperature. In this case, the processing fluid can be discharged from the processing vessel 211 and the processing fluid to be used in processing the next substrate W can be prepared in parallel. This reduces the processing time in the continuous processing.

[0118] After the depressurization step ST24, the process proceeds to the standby step ST21. The processed substrate W is unloaded from the processing container 211, for example, after the process proceeds to the standby step ST21. Specifically, after the depressurization step ST24, supply of inert gas into the processing container 211 begins via the second supply flow path L25. Next, the substrate W is unloaded from the processing container 211 while the inert gas is being supplied into the processing container 211. Even after the substrate W is unloaded from the processing container 211, the supply of inert gas into the processing container 211 continues. In this way, when the substrate W is unloaded from the processing container 211 while the inert gas is being supplied into the processing container 211, the inside of the processing container 211 becomes positive pressure, and a gas flow is formed from the inside to the outside of the processing container 211 when the processing container 211 is opened. Therefore, residue in the processing container 211 can be discharged and removed to the outside of the processing container 211. However, when the substrate W is unloaded from the processing vessel 211, the supply of the inert gas into the processing vessel 211 may be stopped.

[0119] In the substrate processing method according to the second embodiment described above, the heating mechanism HE22 is controlled in the pressure increase step ST22 to increase the temperature of the processing fluid from the first temperature to the second temperature, but this is not limiting. For example, the heating mechanism HE22 may be controlled in the circulation step ST23 to increase the temperature of the processing fluid from the first temperature to the second temperature.

[0120] Furthermore, in the second embodiment, an orifice OR222 is provided downstream of the on-off valve V222 provided on the first supply flow path L22 immediately before the processing vessel 211. Therefore, even if the pressure in the first supply flow path L22 is not reduced before supplying the processing fluid into the processing vessel 211, the orifice OR222 prevents high-pressure fluid from being supplied into the processing vessel 211 immediately after the on-off valve V222 is opened. This prevents the fluid from being supplied to the substrate at a high speed, thereby suppressing pattern collapse.

[0121] [First Modification] A substrate processing apparatus 10A according to a first modification will be described with reference to Fig. 26. Fig. 26 is a diagram showing the substrate processing apparatus 10A according to the first modification.

[0122] 26 , the substrate processing apparatus 10A according to the first modification is different from the substrate processing apparatus 10 according to the first embodiment in that a flow meter FM12 is provided in the first supply flow path L12 upstream of the heating mechanism HE12. The other configurations are the same as those of the substrate processing apparatus 10 according to the first embodiment. The following description will focus on the configurations that differ from the substrate processing apparatus 10 according to the first embodiment.

[0123] The flow meter FM12 is provided in the first supply flow path L12. The flow meter FM12 is provided upstream of the heating mechanism HE12. The flow meter FM12 is provided upstream of the flow rate adjustment mechanism FC12, for example. The flow meter FM12 may be provided downstream of the flow rate adjustment mechanism FC12. The flow meter FM12 detects the flow rate of the treatment fluid flowing through the first supply flow path L12.

[0124] The control unit 14 receives measurement signals from various sensors (such as the flow meter FM12, the temperature sensor T12, and the pressure sensor P18) and transmits control signals to various functional elements. The control signals include, for example, open / close signals for the on-off valves V11, V12, V121, V122, V123, V124, V13, V14, V15, and V18, a set pressure signal for the back pressure valve BV18, an on / off signal for the heating mechanism HE12, a set temperature signal for the heating mechanism HE12, and a set temperature signal for the line heater.

[0125] The control unit 14 controls the heating mechanism HE12 based on the flow rate of the processing fluid detected by the flow meter FM12. For example, when the heater HE122 of the heating mechanism HE12 is in the on state and the flow rate of the processing fluid detected by the flow meter FM12 becomes equal to or lower than a preset threshold, the control unit 14 controls the heater HE122 to switch from the on state to the off state.

[0126] When the density and flow rate of the processing fluid inside the spiral pipe HE121 of the heating mechanism HE12 decreases, the spiral pipe HE121 may experience dry heating. Dry heating occurs, for example, during the depressurization step ST14, when the supply of the processing fluid into the processing vessel 111 is stopped and the processing fluid begins circulating between the circulation flow path L11, the first supply flow path L12, and the return flow path L13. In this dry heating state, the processing fluid has a low density, for example, a gaseous state, making it difficult to exchange heat between the processing fluid and the temperature sensor T12. This makes it difficult to control the processing fluid to a target temperature.

[0127] Conventionally, the control unit 14 continues to control the heater HE122 even if the density inside the spiral tube HE121 decreases, which can cause an abnormal increase in temperature inside the spiral tube HE121 (e.g., overshoot).

[0128] In contrast, according to the first modification, when the flow rate of the processing fluid detected by the flow meter FM12 falls below a threshold while the heater HE122 of the heating mechanism HE12 is in the on state, the control unit 14 controls the heater HE122 to switch from the on state to the off state. In this case, an abnormal rise in the temperature inside the spiral tube HE121 can be reduced. This improves the stability of temperature control at the start of processing, and enables the temperature of the processing fluid to be controlled to the target temperature in a short time.

[0129] [Second Modification] A substrate processing apparatus 20A according to a second modification will be described with reference to Fig. 27. Fig. 27 is a diagram showing the substrate processing apparatus 20A according to the second modification.

[0130] 27 , the substrate processing apparatus 20A according to the second modification differs from the substrate processing apparatus 20 according to the second embodiment in that a flow meter FM22 is provided in the first supply flow path L22 upstream of the heating mechanism HE22. The other configurations are the same as those of the substrate processing apparatus 20 according to the second embodiment. The following description will focus on the configurations that differ from the substrate processing apparatus 20 according to the second embodiment.

[0131] The flow meter FM22 is provided in the first supply flow path L22. The flow meter FM22 is provided upstream of the heating mechanism HE22. The flow meter FM22 detects the flow rate of the processing fluid flowing through the first supply flow path L22.

[0132] The control unit 24 receives measurement signals from various sensors (such as the flow meter FM22, the temperature sensor T22, and the pressure sensor P28) and transmits control signals to various functional elements. The control signals include, for example, open / close signals for the on-off valves V21, V222, V223, V224, V23, V24, V25, and V28, a set pressure signal for the back pressure valve BV28, an on / off signal for the heating mechanism HE22, a set temperature signal for the heating mechanism HE22, and a set temperature signal for the line heater.

[0133] The control unit 24 controls the heating mechanism HE22 based on the flow rate of the processing fluid detected by the flow meter FM22. For example, when the heater HE122 of the heating mechanism HE22 is in the on state and the flow rate of the processing fluid detected by the flow meter FM22 becomes equal to or lower than a preset threshold, the control unit 24 controls the heater HE122 to switch from the on state to the off state.

[0134] When the density and flow rate of the processing fluid inside the spiral pipe HE121 of the heating mechanism HE22 decrease, the spiral pipe HE121 may experience dry heating. Dry heating occurs, for example, during the depressurization step ST24, when the supply of the processing fluid into the processing vessel 211 is stopped and the processing fluid begins circulating between the circulation flow path L21, the first supply flow path L22, and the return flow path L23. In this dry heating state, the density of the processing fluid becomes low, for example, a gas, making it difficult to exchange heat between the processing fluid and the temperature sensor T22. This makes it difficult to control the processing fluid to the target temperature.

[0135] Conventionally, the control unit 24 continues to control the heater HE122 even if the density inside the spiral tube HE121 decreases, which can cause an abnormal increase in temperature inside the spiral tube HE121 (e.g., overshoot).

[0136] In contrast, according to the second modification, when the flow rate of the processing fluid detected by the flow meter FM22 falls below a threshold while the heater HE122 of the heating mechanism HE22 is in the on state, the control unit 24 controls the heater HE122 to switch from the on state to the off state. In this case, an abnormal rise in the temperature inside the spiral tube HE121 can be reduced. This improves the stability of temperature control at the start of processing, and enables the temperature of the processing fluid to be controlled to the target temperature in a short time.

[0137] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0138] In the present disclosure, the control units 14, 24 are electronic circuits such as a CPU (Central Processing Unit), FPGA (Field Programmable Gate Array), ASIC (Application Specific Integrated Circuit), etc., which perform the various control operations described in this specification by executing instruction codes stored in a memory or by being designed as a circuit for a specific application.

[0139] This international application claims priority based on Japanese Patent Application No. 2023-149908, filed on September 15, 2023, the entire contents of which are incorporated herein by reference.

[0140] 111, 211 Processing vessel 12, 22 Fluid supply system HE12, HE22 Heating mechanism L11, L21 Circulation flow path L12, L22 First supply flow path L13, L23 Return flow path S11, S21 Processing fluid supply source W Substrate

Claims

1. A fluid supply system for supplying a processing fluid into a processing vessel in which a substrate having a liquid film formed thereon is processed, comprising: a circulation flow path connected to a fluid supply source for circulating the processing fluid; a supply flow path connecting the circulation flow path to the processing vessel and supplying the processing fluid from the circulation flow path into the processing vessel; a heating mechanism provided in the supply flow path for heating the processing fluid; and a return flow path connecting the circulation flow path to the supply flow path downstream of the heating mechanism and returning the processing fluid from the supply flow path to the circulation flow path.

2. The fluid supply system according to claim 1, further comprising a flow rate adjusting mechanism provided in the supply flow path for adjusting a flow rate of the processing fluid supplied into the processing vessel.

3. The fluid supply system according to claim 2, wherein the flow rate adjustment mechanism is provided upstream of the heating mechanism.

4. The fluid supply system according to claim 2, wherein the flow rate adjustment mechanism is provided downstream of the heating mechanism.

5. The fluid supply system according to claim 1, wherein the processing fluid is in a gaseous or liquid state in the supply flow path upstream of the heating mechanism.

6. The fluid supply system according to any one of claims 1 to 5, wherein the heating mechanism includes a heater that heats the processing fluid by irradiating it with light.

7. A substrate processing apparatus comprising: a processing vessel in which a substrate having a liquid film formed thereon is processed; and a fluid supply system for supplying a processing fluid into the processing vessel, the fluid supply system having: a circulation flow path connected to a fluid supply source for circulating the processing fluid; a supply flow path connecting the circulation flow path to the processing vessel and supplying the processing fluid from the circulation flow path into the processing vessel; a heating mechanism provided in the supply flow path for heating the processing fluid; and a return flow path connecting the circulation flow path to the supply flow path downstream of the heating mechanism and returning the processing fluid from the supply flow path to the circulation flow path.

8. The substrate processing apparatus according to claim 7, wherein the fluid supply system has a flow rate adjusting mechanism provided in the supply flow path for adjusting a flow rate of the processing fluid supplied into the processing vessel.

9. The substrate processing apparatus according to claim 8, wherein the flow rate adjustment mechanism is provided upstream of the heating mechanism.

10. The substrate processing apparatus according to claim 8, wherein the flow rate adjustment mechanism is provided downstream of the heating mechanism.

11. The substrate processing apparatus according to claim 7, wherein the processing fluid is in a gaseous or liquid state in the supply flow path upstream of the heating mechanism.

12. The substrate processing apparatus according to claim 7, wherein the heating mechanism includes a heater that heats the processing fluid by irradiating it with light.

13. A substrate processing apparatus according to any one of claims 7 to 12, further comprising a control circuit, the control circuit controlling the heating mechanism to raise the temperature of the processing fluid from a first temperature to a second temperature while supplying the processing fluid into the processing vessel.

14. A substrate processing apparatus as described in any one of claims 7 to 12, comprising: a discharge flow path that discharges the processing fluid within the processing vessel; and a control circuit, wherein the control circuit circulates the processing fluid between the circulation flow path, the supply flow path, and the return flow path, at least while the processing fluid within the processing vessel is discharged from the discharge flow path without supplying the processing fluid into the processing vessel.

15. A substrate processing apparatus as described in claim 14, comprising a control circuit, wherein the fluid supply system has a temperature sensor provided in the supply flow path downstream of the heating mechanism, and the control circuit circulates the processing fluid between the circulation flow path, the supply flow path and the return flow path until the temperature of the processing fluid detected by the temperature sensor reaches a target temperature.

16. A substrate processing apparatus as claimed in any one of claims 7 to 12, further comprising a control circuit, the fluid supply system having a depressurization passage for discharging the processing fluid from the return passage, and the control circuit discharging the processing fluid from the return passage from the depressurization passage before supplying the processing fluid into the processing vessel.

17. A substrate processing apparatus as described in any one of claims 7 to 12, comprising a control circuit which increases the pressure in the processing vessel by setting a supply flow rate of the processing fluid supplied into the processing vessel to a first flow rate until the pressure in the processing vessel reaches a first pressure, and when the pressure in the processing vessel reaches the first pressure, sets the supply flow rate to a second flow rate greater than the first flow rate to further increase the pressure in the processing vessel.

18. A substrate processing apparatus as described in claim 7, wherein the fluid supply system comprises: a flow meter provided in the supply flow path upstream of the heating mechanism for detecting a flow rate of the processing fluid flowing through the supply flow path; and a control circuit, wherein the control circuit controls the heating mechanism based on the flow rate of the processing fluid detected by the flow meter.

19. A substrate processing method using a substrate processing apparatus, the substrate processing apparatus comprising: a processing vessel in which a substrate having a liquid film formed thereon is processed; a fluid supply system for supplying a processing fluid into the processing vessel; and a discharge passage for discharging the processing fluid from the processing vessel, the fluid supply system comprising: a circulation passage connected to a fluid supply source for circulating the processing fluid; a supply passage connecting the circulation passage and the processing vessel and supplying the processing fluid from the circulation passage into the processing vessel; a heating mechanism provided in the supply passage for heating the processing fluid; and a return passage connecting the circulation passage and the supply passage downstream of the heating mechanism and returning the processing fluid from the supply passage to the circulation passage, the method comprising the steps of: increasing pressure in the processing vessel by supplying the processing fluid into the processing vessel; and circulating the processing fluid in the processing vessel by supplying the processing fluid into the processing vessel and discharging the processing fluid in the processing vessel from the discharge passage. a step of reducing pressure inside the processing vessel by discharging the processing fluid inside the processing vessel from the discharge passage without supplying the processing fluid into the processing vessel, wherein the step of increasing pressure or the step of circulating includes controlling the heating mechanism to increase the temperature of the processing fluid from a first temperature to a second temperature while supplying the processing fluid into the processing vessel.

20. The substrate processing method according to claim 19, further comprising a step of circulating the processing fluid between the circulation flow path, the supply flow path and the return flow path, the circulating step being performed at least while the depressurizing step is being performed.

21. The substrate processing method of claim 19 or 20, wherein the step of increasing the pressure in the processing vessel includes increasing the pressure in the processing vessel by setting a supply flow rate of the processing fluid supplied into the processing vessel at a first flow rate until the pressure in the processing vessel reaches a first pressure, and, when the pressure in the processing vessel reaches the first pressure, further increasing the pressure in the processing vessel by setting the supply flow rate to a second flow rate greater than the first flow rate.

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