Substrate processing apparatus, substrate processing method, gas regeneration system, and gas regeneration method

Abstract

Embodiments provide a substrate processing apparatus, a substrate processing method, a gas recovery system, and a gas recovery method that can suppress an increase in the cost of rare gas and reduce the initial cost and maintenance cost of a gas recovery device, and the like. The gas recovery method of the embodiments includes an operation of setting a prescribed reference based on the flow rate of rare gas set in a process recipe, selecting a rare gas recovery step based on the prescribed reference, guiding exhaust gas from a prescribed chamber to a rare gas recovery device in the rare gas recovery step, and causing the exhaust gas to avoid the rare gas recovery device in a step other than the rare gas recovery step.

Description

[0001] [Related Applications]

[0002] This application claims priority to Japanese Patent Application No. 2021-034727 (filed on March 4, 2021). This application includes all contents of the basic application by reference to that basic application. Technical Field

[0003] This embodiment relates to a substrate processing apparatus, a substrate processing method, a gas regeneration system, and a gas regeneration method. Background Technology

[0004] For example, one of the manufacturing processes for semiconductor devices is an etching process that forms a predetermined pattern on a semiconductor substrate such as a silicon wafer. In this process, an etching gas corresponding to the material being etched is used. Alternatively, nitrogen or hydrogen may be used as a dilution gas or auxiliary gas along with the etching gas.

[0005] Furthermore, in recent years, there has been a trend to use rare gases such as krypton (Kr) or xenon (Xe) in conjunction with etching gases. These gases exist in only trace amounts in nature and cannot be synthesized. Therefore, compared to naturally abundant nitrogen or synthetically produced hydrogen, rare gases tend to be more expensive and harder to obtain. Thus, for example, gas regeneration equipment is used to separate rare gases from the gas discharged from the etching chamber and recover them for reuse. Depending on the volume of discharged gas, large-scale gas regeneration equipment may be required, or maintenance may be expensive and time-consuming, increasing both the initial cost and maintenance costs of the gas regeneration equipment. Summary of the Invention

[0006] The problem to be solved by the present invention is to provide a substrate processing apparatus, a substrate processing method, a gas regeneration system, and a gas regeneration method that can suppress the increase of rare gas costs and reduce the initial cost and maintenance cost of gas regeneration equipment.

[0007] The gas regeneration method of the embodiment includes the following operations: setting a predetermined reference based on the flow rate of the rare gas set in the process formulation; selecting a rare gas recovery step based on the predetermined reference; in the rare gas recovery step, directing the exhaust gas from a predetermined chamber to a rare gas regeneration device; and in steps other than the rare gas recovery step, causing the exhaust gas to bypass the rare gas regeneration device. Attached Figure Description

[0008] Figure 1 This is a schematic diagram illustrating a substrate processing apparatus according to an embodiment.

[0009] Figure 2This is a diagram illustrating an example of a process formulation.

[0010] Figure 3 This is a flowchart illustrating the substrate processing method of this embodiment.

[0011] Figure 4A This is a schematic diagram showing the substrate processing apparatus of Comparative Example 1. Figure 4B This is a schematic diagram showing the substrate processing apparatus of Comparative Example 2.

[0012] Figure 5 This is a schematic diagram showing the substrate processing apparatus of Variation Example 1.

[0013] Figure 6 This is a schematic diagram showing the substrate processing apparatus of Variation Example 2. Detailed Implementation

[0014] Hereinafter, non-limiting exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In all accompanying drawings, the same or corresponding reference numerals are used to denote the same or corresponding components or parts, and repeated descriptions are omitted. Furthermore, the drawings are not intended to show relative comparisons between components or parts, or between the thicknesses of various layers; therefore, specific thicknesses or dimensions can be determined by the industry based on the following non-limiting embodiments.

[0015] Figure 1 This is a schematic diagram illustrating a substrate processing apparatus according to an embodiment. In this embodiment, an etching apparatus is exemplified as the substrate processing apparatus. Figure 1 As shown, the substrate processing apparatus 1 of this embodiment includes: a chamber 10 capable of housing a semiconductor wafer as a substrate to be processed; a gas supply system 20 for supplying processing gas to the chamber; a gas discharge system 30 for discharging the gas from the chamber; and a control unit 40 for controlling the substrate processing apparatus 1 in general.

[0016] A support stage 10S is disposed in the chamber 10, and a semiconductor wafer W (hereinafter simply referred to as wafer W) serving as the substrate to be processed is placed thereon. The support stage 10S may, for example, have a heater (not shown), thereby enabling the wafer W placed on the support stage 10S to be heated to a predetermined temperature. In addition, the chamber 10 has a cluster nozzle 10H, which uniformly supplies processing gas supplied to the internal space to the wafer W on the support stage 10S. The support stage 10S may be the lower electrode for supplying high-frequency power, and the cluster nozzle 10H may be the upper electrode. In this case, the chamber 10 can be used as a plasma etching chamber. The chamber 10 is formed of aluminum, for example. In addition, when using plasma, the inner surface of the chamber 10 may be coated with a material with high plasma resistance, such as alumina (Al2O3) or yttrium oxide (Y2O3). An opening is provided on the side wall of chamber 10 for moving wafer W into or out of chamber 10. A loading lock chamber (not shown) can be installed at the opening via a gate valve. In addition, chamber 10 is provided with a supply port 10I and an outlet port 10E for processing gas.

[0017] The gas supply system 20 may include, for example, a gas supply pipe 20I connected to a supply port 10I of the chamber 10; multiple gas pipes 20L converging with the gas supply pipe 20I; and a gas supply source (not shown) connected to the gas pipes 20L, capable of supplying a specified gas to each gas pipe 20L. A flow controller (MFC), such as a mass flow meter, is installed in each gas pipe 20L. Multiple gases are supplied from the gas supply source to the gas pipes 20L, flow in each gas pipe 20L under the flow control of the flow controller (MFC), and are introduced into the chamber 10 from the gas supply pipe 20I. "Gas A" in the illustration may be, for example, an etching gas, and "Gas B" may be a dilution gas. The etching gas can be appropriately determined according to the object being etched, and the dilution gas may be, for example, hydrogen (H2) or nitrogen (N2). Furthermore, when multiple etching gases are used, "Gas C" may be other etching gases; and when oxygen (O2) is used as an auxiliary gas for the etching gas "Gas A", "Gas C" may also be O2 gas. In addition, Kr gas is exemplified as a rare gas in the following description, but xenon (Xe), helium (He), neon (Ne), argon (Ar), and radon (Rn) can also be used instead of Kr gas. Furthermore, the gases supplied to chamber 10, including etching gas, rare gas, dilution gas, other etching gases, and auxiliary gases, are sometimes collectively referred to as processing gases.

[0018] The gas exhaust system 30 includes a turbomolecular pump 31 installed at the exhaust port of chamber 10. The turbomolecular pump 31 is connected to an exhaust pipe 32, and a flow path switching valve 33 is installed on the exhaust pipe 32. The flow path switching valve 33 has one intake port and two exhaust ports, with the intake port connected to the exhaust pipe 32. One exhaust port is connected to an exhaust pipe 34A, and the other exhaust port is connected to an exhaust pipe 34B. Using the flow path switching valve 33, flow path A from the exhaust pipe 32 to the exhaust pipe 34A and flow path B from the exhaust pipe 32 to the exhaust pipe 34B are selectively established.

[0019] Dry vacuum pumps 35A and 35B, which serve as auxiliary pumps for turbomolecular pump 31, are connected to discharge pipes 34A and 34B, respectively. Discharge pipe 36A is connected to the outlet of dry vacuum pump 35A, and discharge pipe 36A is connected to gas regeneration device 37. Gas regeneration device 37 is provided to separate Kr gas from the gas discharged from chamber 10, and can be, for example, a gas regeneration device using pressure variation adsorption (PSA), thermal variation adsorption (TSA), vacuum pressure variation (VPSA), or gas chromatography-mass spectrometry (GC-Mass). Alternatively, gas regeneration devices using hollow fiber membranes or thin films for adsorption, or gas regeneration devices using cryogenic distillation based on differences in liquefaction temperature, can also be used. Furthermore, gas regeneration device 37 can be constructed by combining two or more of these gas regeneration devices.

[0020] A discharge pipe 38 is connected to the outlet of the gas regeneration device 37. The discharge pipe 36B from the dry vacuum pump 35B merges with the discharge pipe 38. Unlike the discharge pipe 36A, the discharge pipe 36B does not have a gas regeneration device. Additionally, a waste gas treatment device 39 for treating the gas discharged from the chamber 10 is connected to the discharge pipe 38.

[0021] Based on the above configuration, when flow path A is established using flow path switching valve 33, the gas discharged from chamber 10 flows to exhaust gas treatment device 39 via turbomolecular pump 31, dry vacuum pump 35A, and gas regeneration device 37. At this time, the Kr gas separated from the discharged gas by gas regeneration device 37 is filled into a designated recovery container (not shown) for reuse. Alternatively, when flow path B is established using flow path switching valve 33, the gas discharged from chamber 10 flows to exhaust gas treatment device 39 via turbomolecular pump 31 and dry vacuum pump 35B. In exhaust gas treatment device 39, harmful components contained in the discharged gas are removed, and the remaining gas is released into the atmosphere.

[0022] The control unit 40 can be implemented as a computer including a CPU (Central Processing Unit), ROM (Read-Only Memory), RAM (Random Access Memory), etc. Alternatively, the control unit 40 can be implemented using hardware such as an Application-Specific Integrated Circuit (ASIC), a Programmable Gate Array (PGA), or a Field Programmable Gate Array (FPGA). Furthermore, the control unit 40 includes a display unit 40D such as a display device and an input unit 40I such as a keyboard. The process recipe (or simply recipe) is displayed on the display unit 40D, and process parameters such as the flow rate of the processing gas (etching gas, auxiliary gas, rare gas, dilution gas, etc.), the pressure inside the chamber 10, the temperature of the support stage 10S, and the time of each processing step can be input into the input field of the recipe via the input unit 40I. Based on the recipe, the control unit 40 sends indication signals to the flow controller MFC, the flow path switching valve 33, the turbomolecular pump 31, and the dry vacuum pumps 35A and 35B, etc. In other words, the control unit 40 controls each control machine based on the formula, for example, causing the substrate processing apparatus 1 to perform the following substrate processing method. Furthermore, the control unit 40, together with the gas exhaust system 30, constitutes the gas regeneration system 43.

[0023] The formulation is, for example, a program that can set the sequence of each step of the process, the process parameters (temperature, pressure, gas type and flow rate, time) in each step, in tabular form, so that the substrate processing method is executed by controlling the various control devices (flow controller, pressure controller, temperature regulator, etc.) of the substrate processing apparatus through the control unit 40. The process formulation (and various associated data) can be downloaded to the control unit 40, for example, from non-transitory computer-readable storage media such as hard disk drives (HDDs), semiconductor memories, servers, etc., via wired or wireless means. In addition, the process parameters can be appropriately changed at the start of the process.

[0024] Figure 2 This is a diagram illustrating an example of a formulation, displayed on display unit 40D of control unit 40. The illustrated formulation RP is, for example, a formulation for a substrate processing method (specifically, an etching process), using Kr gas as a rarefaction gas. As shown, in each processing step, set values ​​are input for time (seconds) and Kr flow rate (sccm). However, in… Figure 2For ease of explanation, process parameters such as the flow rates of etching gas and dilution gas, the pressure inside chamber 10, the temperature of wafer W, and the high-frequency power supplied to the electrodes (cluster ejector 10H, support stage 10S) inside chamber 10 are omitted. Furthermore, the total flow rate in this formulation RP is the sum of the flow rates of the processing gases (etching gas, auxiliary gas, Kr gas, and dilution gas) supplied to chamber 10, and is automatically displayed by inputting these settings. The Kr ratio represents the ratio of the Kr gas flow rate to the total flow rate in each step, the usage amount is the amount of Kr gas used in each step (flow rate × time), and the usage rate is the amount of Kr gas used in each step relative to the total amount of Kr gas used in the entire process. These can also be automatically displayed based on the set values.

[0025] According to the formula RP, for example, in processing step No. 6, Kr gas is supplied to chamber 10 at a flow rate of 100 sccm for 120 seconds. The usage at this time is 200 cc (100 sccm × 120 seconds / 60 seconds), and the ratio of Kr gas flow rate to the total flow rate of 500 sccm in this processing step is 20%. Alternatively, for example, in processing step No. 10, Kr gas is supplied to chamber 10 at a flow rate of 50 sccm for 1000 seconds (16 minutes and 40 seconds). The usage at this time is 833 cc, and the ratio of Kr gas flow rate to the total flow rate of 250 sccm in this processing step is 41.7%. On the other hand, in processing steps No. 19 and 20, no Kr gas is supplied (set value = 0).

[0026] Furthermore, as shown in the figure, with the Kr gas flow rate set, the total Kr gas usage in the entire process is 2000cc (2 liters). For example, in processing step No.1, only 0.6% of the total Kr gas is used, while in processing step No.10, 41.7% of the total Kr gas is used. Processing step No.1 is named "stability" because its purpose is to stabilize the flow rate of the processing gas, while the actual etching process is performed in processing step No.10 (processing step name: ME4). Thus, in a process, the amount of Kr gas used in each processing step varies significantly depending on the actual processing performed in that step.

[0027] Next, refer to Figure 3 Based on Figure 2 The formula RP shown is in Figure 1 Taking the substrate processing apparatus 1 shown as an example, the substrate processing method of this embodiment will be described. Figure 3This is a flowchart illustrating the substrate processing method of this embodiment. In step S10, firstly, the total amount of Kr gas supplied to chamber 10 is calculated for each processing step of the formulation RP. Specifically, the amount of Kr gas used in each step is calculated based on the Kr gas flow rate set for each step and the time required for that step. Then, the total amount of Kr gas used is obtained by summing these amounts. Figure 2 The example shown in formulation RP is 2000cc. Next, for each processing step, the utilization rate of the usage relative to the total usage is calculated (refer to...). Figure 2 ).

[0028] Next, in step S11, a baseline utilization rate is set. The baseline utilization rate can be appropriately determined, for example, based on the percentage of Kr gas (target recovery rate) in the total amount of Kr gas used for recovery. For example, according to formulation RP, in processing step No. 10, more than 41% of the total Kr gas is used. Additionally, in processing steps No. 6 and No. 10, a combined total of more than 51% of the total Kr gas is used. Furthermore, if processing steps No. 4, 12, and 18 are added to processing steps No. 6 and 10, then these five processing steps (No. 4, 6, 10, 12, and 18) will use more than 77% of the total Kr gas. Furthermore, if processing steps No. 8, 14, and 16 are added, then these eight processing steps (No. 4, 6, 8, 10, 12, 14, 16, and 18) will use more than 96% of the total Kr gas.

[0029] Based on the above, for example, if approximately 41% of the Kr gas should be recovered, considering 41% as the utilization rate for processing step No. 10, for example, 40% can be set as the baseline utilization rate. Furthermore, for example, if approximately 52% of the Kr gas should be recovered, considering 10% as the utilization rate for processing step No. 6, for example, 9% can be set as the baseline utilization rate. Moreover, if a maximum of 77% of the Kr gas should be recovered, considering 8.3% as the utilization rate for processing steps No. 5 and 12, for example, 8% can be set as the baseline utilization rate. Furthermore, if a maximum of 96% of the Kr gas should be recovered, considering 6.3% as the utilization rate for processing steps No. 8 and 16, for example, 6% can be set as the baseline utilization rate.

[0030] Then, in step S12, a process based on formulation RP is started in the substrate processing apparatus 1. Furthermore, the wafer W (which serves as the substrate to be processed) Figure 1The wafer is moved into the chamber 10 at least before the process begins and placed on the support stage 10S. In addition, the formulation RP also sets the flow rates of etching gas and dilution gas, the pressure inside the chamber 10, the temperature of the wafer W, and the high-frequency power supplied to the electrodes inside the chamber 10. Based on these, the control unit 40 outputs instruction signals to each control machine of the substrate processing apparatus 1 to perform the process on the wafer W.

[0031] When processing step No. N begins (in the case of formula RP, N is an integer from 1 to 20) (step S13), it is determined whether processing step No. N is equivalent to the Kr gas recovery step (step S14). That is, it is determined whether the utilization rate in processing step No. N is above the baseline utilization rate. If it is determined that processing step No. N is equivalent to the Kr gas recovery step (step S14: Yes), that is, if the utilization rate in processing step No. N is above the baseline utilization rate, flow path A is established using flow path switching valve 33. Figure 1 In other words, the processing gas supplied to chamber 10 facilitates the etching of wafer W within chamber 10. After being discharged by turbomolecular pump 31, it is directed from dry vacuum pump 35A to gas regeneration device 37. Thus, in processing step No. N, the gas regeneration device 37 recovers the Kr gas from the exhaust gas from chamber 10 and fills it into a recovery container (not shown). On the other hand, the remaining exhaust gas is released into the atmosphere through waste gas treatment device 39.

[0032] On the other hand, if it is determined that processing step No. N is not equivalent to the Kr gas recovery step (step S14: No), that is, if the utilization rate in processing step No. N is less than the baseline utilization rate, flow path B is established using flow path switching valve 33. Figure 1 In other words, the processing gas supplied to chamber 10 is discharged by turbomolecular pump 31 and then flows to waste gas treatment device 39 via dry vacuum pump 35B. That is, the exhaust gas from chamber 10 bypasses gas regeneration device 37 and flows to waste gas treatment device 39, therefore, Kr gas is not separated.

[0033] Furthermore, for example, when the baseline utilization rate is set at 8%, in formulation RP, processing steps No. 4, 6, 10, 12, and 18, where the utilization rate exceeds 8%, are equivalent to the Kr gas recovery steps. That is, in processing steps No. 4, 6, 10, 12, and 18, flow path A is established, and the discharged gas is directed to the gas regeneration device 37. In processing steps other than No. 4, 6, 10, 12, and 18, flow path B is established, and the discharged gas bypasses the gas regeneration device 37.

[0034] When a processing step No. N ends, the process proceeds to the next processing step No. N+1 (step S17), and determines whether all processing steps have ended (step S18). If it is determined that all processing steps have not ended (step S18: No), the process returns to step S13, repeating steps S13 to S17 until all processing steps have ended. If it is determined that all processing steps have ended (step S18: Yes), the process ends.

[0035] Next, refer to Figure 4A and Figure 4B The effects of the substrate processing apparatus 1 and substrate processing method of this embodiment will be explained. Figure 4A This is a schematic diagram showing the substrate processing apparatus of Comparative Example 1. Figure 4B This is a schematic diagram showing the substrate processing apparatus of Comparative Example 2. (Refer to...) Figure 4A The substrate processing apparatus 100 of Comparative Example 1 has an on / off valve 330 that differs from the flow path switching valve 33 in the substrate processing apparatus 1 of Embodiment 1. The on / off valve 330 has an intake port and an exhaust port; therefore, no exhaust pipe corresponding to the exhaust pipe 34B in Embodiment 1 and no auxiliary pump corresponding to the dry vacuum pump 35B are provided. In other words, if the on / off valve 330 is opened, only the flow path from the turbomolecular pump 31 to the dry vacuum pump 35A is established. Furthermore, the exhaust pipe 36A of the dry vacuum pump 35A is directly connected to the intake port of the waste gas treatment device 39, and no gas regeneration device corresponding to the gas regeneration device 37 in Embodiment 1 is provided on the exhaust pipe 36A. The other components of the substrate processing apparatus 100, including the gas supply system and the chamber 10, are the same as those of the substrate processing apparatus 1.

[0036] Next, if referring to Figure 4B Therefore, the substrate processing apparatus 200 of Comparative Example 2 also has an on / off valve 330, establishing only the flow path from the turbomolecular pump 31 to the dry vacuum pump 35A. Furthermore, unlike the substrate processing apparatus 100 of Comparative Example 1, the discharge pipe 36A of the dry vacuum pump 35A in Comparative Example 2 is connected to the gas regeneration device 37. Therefore, the gas discharged from the chamber 10 always flows to the gas regeneration device 37, where the Kr gas is separated and recovered. The other components of the substrate processing apparatus 200, including the gas supply system and the chamber 10, are the same as those of the substrate processing apparatus 1.

[0037] In the substrate processing apparatus 100 of Comparative Example 1, for example, when performing a substrate processing method based on a prescribed formula, it is difficult to separate and recover Kr gas from the gas discharged from chamber 10. Therefore, it becomes necessary to purchase large quantities of Kr gas, which exists only in trace amounts in nature and is often expensive. On the other hand, in the substrate processing apparatus 200 of Comparative Example 2, Kr gas is always separated and recovered from the gas discharged from chamber 10. That is, the gas regeneration device 37 is always operating. Therefore, there is a possibility that not only will power consumption increase, but the maintenance frequency and cost of the gas regeneration device 37 will also increase. Furthermore, while using a large-scale gas regeneration device can reduce the maintenance frequency, for example, in the case of an adsorption-based gas regeneration device, a large-scale gas regeneration device will incur significant initial costs and operating costs.

[0038] In contrast, according to the substrate processing apparatus 1 and substrate processing method of this embodiment, the Kr gas utilization rate in each processing step is calculated based on the formula RP. In processing steps where the utilization rate is above a predetermined baseline utilization rate (Kr gas recovery step), Kr gas is recovered by establishing flow path A using flow path switching valve 33. That is, Kr gas is recovered in the Kr gas recovery step, so the gas regeneration equipment 37 is substantially operational in the Kr gas recovery step and is essentially in standby mode in processing steps other than the Kr gas recovery step. Therefore, it is possible to prevent an unnecessary increase in the power consumption of the gas regeneration equipment 37 and to prevent an unnecessary increase in the maintenance frequency. On the other hand, in processing steps other than the Kr gas recovery step, Kr gas is released without being separated and recovered, but a considerable amount of Kr gas in the total usage can be separated and recovered. In other words, according to the substrate processing apparatus 1 and substrate processing method of this embodiment, even without the gas regeneration equipment 37 being constantly running, Kr gas can be separated and recovered in processing steps where the amount of Kr gas used increases. Therefore, the initial cost and maintenance cost of the gas regeneration equipment 37 can be reduced while taking into account the purchase cost of Kr gas.

[0039] (Example of variation)

[0040] Next, a variation of the substrate processing apparatus 1 in this embodiment will be described. Figure 5This is a schematic diagram showing the substrate processing apparatus 50 of Variation Example 1. As shown, the substrate processing apparatus 50 is a so-called clustered process device having multiple chambers, namely chambers 54A to 54F. For example, the substrate processing apparatus 50 is provided with multiple stages 51 for mounting FOUPs (Front Opening Unified Pods), and the FOUPs mounted on the stages 51 are hermetically connected to a loading lock chamber 52. A pump (not shown) is provided in the loading lock chamber 52, thereby maintaining a reduced pressure inside the loading lock chamber 52. Furthermore, a transfer robot 52R is provided in the loading lock chamber 52, thereby transferring wafers between the FOUPs and the transfer robot 53R described below. Additionally, the loading lock chamber 52 is hermetically connected to a transfer chamber 53 via a predetermined passage.

[0041] The transfer chamber 53 has a polygonal shape when viewed from above, and each side is connected to chambers 54A to 54F via gate valves (not shown). A vacuum pump (not shown) is connected to the transfer chamber 53, thereby maintaining a reduced pressure inside the transfer chamber 53. A transfer robot 53R is also installed inside the transfer chamber 53. The transfer robot 53R can directly or indirectly receive wafers from the loading lock chamber 52 and transfer them to any of the chambers 54A to 54F. It can also remove wafers from any of the chambers 54A to 54F and hand them over to the transfer robot 52R. Furthermore, the transfer robot 53R can also transfer wafers from one of the chambers 54A to 54F to another chamber.

[0042] Inside chambers 54A to 54F are support stages (not shown) for supporting wafers. Additionally, one or more of chambers 54A to 54F may be etching chambers, while the others may be ashing chambers or thin film deposition chambers. With this configuration, etching, resist removal, and thin film deposition processes can be performed concurrently. Alternatively, chambers 54A to 54F may all be etching chambers. This allows for the parallel etching of multiple wafers, thus enabling high-throughput etching. Gas supply systems corresponding to the processes performed within chambers 54A to 54F are connected to these chambers.

[0043] Additionally, turbomolecular pumps (not shown) are connected to each chamber 54A-54F, and the discharge pipes of the turbomolecular pumps are connected to dry vacuum pumps 55A-55F. Furthermore, flow path switching valves 33A-33F are respectively installed on the discharge pipes of the dry vacuum pumps 55A-55F. Flow path switching valves 33A-33F, like the flow path switching valve 33 in the substrate processing apparatus 1 of the embodiment, have one intake port and two exhaust ports. Therefore, flow path switching valves 33A-33F can be switched to direct the exhaust gas from the dry vacuum pumps 55A-55F to the gas regeneration device 37 and to the waste gas treatment device 39, respectively. The gas regeneration device 37 separates Kr gas from the exhaust gas, discharges it to a recovery container, and discharges the residual gas to the waste gas treatment device 39.

[0044] Furthermore, the substrate processing apparatus 50 is equipped with control units 401 and 402, which have the same configuration as the control unit 40 in the substrate processing apparatus 1. Control units 401 and 402 are electrically connected to each other and can send and receive information between them. The substrate processing performed in the substrate processing apparatus 50 is comprehensively controlled in the control unit 402 based on the process formulation. The control unit 401 receives information related to gas supply from the control unit 401 and controls the separation and recovery of Kr gas based on this information. Moreover, either control unit 401 or 402 can be used to comprehensively control the substrate processing, including the separation and recovery of Kr gas.

[0045] Specifically, from the process formula set in the control unit 402 for the entire substrate processing apparatus 50, the control unit 401 obtains the process formula corresponding to each chamber 54A to 54F. In the control unit 401, a Kr gas recovery step is set for the process performed in each chamber 54A to 54F. Simultaneously with the start of the Kr gas recovery step, the exhaust gas from each chamber 54A to 54F is directed to the gas regeneration device 37. When steps other than the Kr gas recovery step begin, the exhaust gas does not flow to the gas regeneration device 37 but reaches the waste gas treatment device 39. Thus, in the substrate processing apparatus 50 of Variation 1, the substrate processing method described above can also be applied to each chamber 54A to 54F, thereby achieving the same effect as that achieved by the substrate processing apparatus 1 of the embodiment.

[0046] Next, the substrate processing apparatus 60 of Variation Example 2 of this embodiment will be described. Figure 6This is a schematic diagram showing the substrate processing apparatus 60 of Variation Example 2. As shown, the substrate processing apparatus 60 is also a cluster-type process device, similar to the substrate processing apparatus 50. However, in the substrate processing apparatus 60, the discharge pipes of the dry vacuum pumps 55A to 55F are connected to the connecting pipe 56 and are combined into a single pipe, on which a flow path switching valve 33G is installed. The flow path switching valve 33G, like the flow path switching valve 33 of the substrate processing apparatus 1, has one intake port and two exhaust ports. Except for this configuration (and the configurations that are modified accordingly), the substrate processing apparatus 60 has the same configuration as the substrate processing apparatus 50. In addition, the control unit 403 corresponds to the control unit 401 of the substrate processing apparatus 50, and the control unit 404 corresponds to the control unit 402 of the substrate processing apparatus 50. Descriptions of other configurations that are the same as those of the substrate processing apparatus 50 are omitted.

[0047] In the substrate processing apparatus 60 of Variation 2, the gases discharged from all chambers 54A to 54F are combined by the connecting pipe 56, so the reference gas is not included. Figure 3 The described substrate processing method is applied to each of the chambers 54A to 54F, and the control unit 403 can generate, for example, a timing diagram regarding the Kr gas based on the process formula set in the control unit 404. Specifically, a timing diagram can be generated that records the ratio (Kr gas flow rate ratio) of the total Kr gas flow rate to the total gas flow rate supplied to chambers 54A to 54F relative to a time axis. Based on this, if the specified Kr gas flow rate ratio continues for a specified period, this period can be set as a Kr gas recovery step.

[0048] Then, during the Kr gas recovery step, the flow path switching valve 33 is used to guide the exhaust gas converging through the connecting pipe 56 to the gas regeneration device 37, where the Kr gas is separated and recovered. Outside of the Kr gas recovery step, the flow path switching valve 33 is used to prevent the exhaust gas converging through the connecting pipe 56 from flowing to the gas regeneration device 37 and instead flow to the waste gas treatment device 39. Thus, the same effect as that achieved by the substrate processing method can be achieved. In addition, since the substrate processing apparatus 60 of Variation Example 2 does not provide a flow path switching valve (33) for each chamber 54A to 54F, it can be easily constructed.

[0049] (Other variations)

[0050] In the description of the substrate processing method in the embodiment, a baseline utilization rate is determined, and steps with a utilization rate of or higher than the baseline utilization rate are designated as Kr gas recovery steps. However, this is not a limitation; the amount of Kr gas used in each processing step of the formulation RP can also be calculated, and a baseline utilization amount can be determined based on this. Steps with a utilization amount of or higher than the baseline utilization amount are designated as Kr gas recovery steps. For example, in Figure 2In this example, if the baseline usage is set to, for instance, 150cc, then processing steps No. 6, 10, and 15 can be set as Kr gas recovery steps. Then, during processing steps No. 6, 10, and 15, flow path A is established using flow path switching valve 33, and Kr gas is separated and recovered from the exhaust gas in the gas regeneration device 37. Furthermore, in processing steps other than these, flow path B is established using flow path switching valve 33, so the exhaust gas does not flow in the gas regeneration device 37 but flows into the waste gas treatment device 39. This also achieves the target recovery amount.

[0051] Furthermore, the timing diagram described in relation to the substrate processing apparatus 60 of Variation 2 can also be produced in the substrate processing method of the substrate processing apparatus 1 of the Use Embodiment or the substrate processing apparatus 50 of Variation 1. That is, in the substrate processing apparatuses 1 and 50, similarly, when the specified rare gas flow rate ratio is maintained for a specified period, this period can be set as a rare gas recovery step.

[0052] In addition, when using rare gases diluted with hydrogen or nitrogen, the concentration of rare gases should be taken into account when calculating the flow ratio of rare gases to the total flow rate in each processing step, as well as the amount of rare gases used, the total amount used, and the utilization rate.

[0053] Several embodiments of the present invention have been described, but these embodiments are provided by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other ways, with various omissions, substitutions, and modifications made without departing from the spirit of the invention. These embodiments or variations thereof are included in the scope or spirit of the invention, and are included in the scope of the invention as set forth in the claims and its equivalents.

[0054] [Explanation of Symbols]

[0055] 1, 50, 60 substrate processing apparatus

[0056] 10. Chambers 54A to 54F

[0057] 20 Gas supply system

[0058] 30 Gas Exhaust System

[0059] 40, 401-404 Control Unit

[0060] 31 Turbomolecular Pump

[0061] 33, 33A~33F Flow path switching valve

[0062] 35A, 35B, 55A-55F dry vacuum pumps

[0063] 37 Gas regeneration equipment

[0064] 39. Waste gas treatment device

[0065] 51 units

[0066] 52 Loading the locked chamber

[0067] 52R Transport Robot

[0068] 53 Transport room

[0069] 53R Transport Robot.

Claims

1. A gas regeneration method, comprising the following operations: The specified baseline is set based on the flow rate of the rare gas specified in the process formulation; The rare gas recovery steps are selected based on the aforementioned criteria; In the rare gas recovery step, the exhaust gas from the designated chamber is directed to the rare gas regeneration device; and In steps other than the rare gas recovery step, the exhaust gas is discharged, bypassing the rare gas regeneration equipment; in The operation of setting the specified benchmark includes the following operations: Calculate the amount of rare gas used in each step of the process formulation; Sum the rare gas usage in each step and calculate the total usage. Calculate the usage rate of each step relative to the total usage; as well as A baseline utilization rate is set based on the calculated utilization rate; The operation of selecting the rare gas recovery step includes the following operations: Steps with a utilization rate higher than the benchmark utilization rate are selected as rare gas recovery steps, while steps with a utilization rate lower than the benchmark utilization rate are not selected as rare gas recovery steps.

2. A substrate processing method, comprising the following operations: The substrate of the object to be processed is moved into the chamber; and When the substrate is processed according to the process parameters set in the process formulation, the gas regeneration method according to claim 1 is performed.

3. A gas regeneration system, comprising: chamber; A gas exhaust system, connected to the chamber, includes a gas regeneration device; and The control unit sets a predetermined reference based on the flow rate of the rare gas specified in the process formula, selects a rare gas recovery step based on the predetermined reference, and guides the discharged gas to a rare gas regeneration device in the rare gas recovery step. In steps other than the rare gas recovery step, the discharged gas is discharged bypassing the rare gas regeneration device. The control unit calculates the rare gas usage amount for each step of the process formulation, sums the rare gas usage amounts for each step to obtain the total usage amount, calculates the usage rate of each step relative to the total usage amount, sets a benchmark usage rate based on the calculated usage rate, and sets the prescribed benchmark. The control unit selects steps with a utilization rate greater than or equal to the benchmark utilization rate as rare gas recovery steps, and does not select steps with a utilization rate less than the benchmark utilization rate as rare gas recovery steps.

4. The gas regeneration system according to claim 3, wherein The gas exhaust system further includes: 1st flow path; The second flow path; and The flow path switching unit switches between a first state that connects the chamber to the first flow path and a second state that connects the chamber to the second flow path; The gas regeneration device is located in the first flow path. In the rare gas recovery step, the control unit switches the flow path switching unit to the first state, and in steps other than the rare gas recovery step, switches the flow path switching unit to the second state.

5. A substrate processing apparatus comprising: chamber; A gas supply system is connected to the chamber; A gas exhaust system is connected to the chamber; and The control unit controls the gas supply system and the gas discharge system; The gas exhaust system has: 1st flow path; 2nd flow path; The flow path switching unit switches between a first state that connects the chamber to the first flow path and a second state that connects the chamber to the second flow path; as well as A rare gas regeneration device is installed in the first flow path; in The control unit is configured to set a predetermined reference based on the flow rate of the rare gas set in the process formula, select a rare gas recovery step based on the predetermined reference, and control the flow path switching unit in such a way that the discharged gas is directed to the rare gas regeneration device in the rare gas recovery step, and the discharged gas is avoided by the rare gas regeneration device in steps other than the rare gas recovery step. The control unit calculates the rare gas usage amount for each step of the process formulation, sums the rare gas usage amounts for each step to obtain the total usage amount, calculates the usage rate of each step relative to the total usage amount, sets a benchmark usage rate based on the calculated usage rate, and sets the prescribed benchmark. The control unit selects steps with a utilization rate greater than or equal to the benchmark utilization rate as rare gas recovery steps, and does not select steps with a utilization rate less than the benchmark utilization rate as rare gas recovery steps.

6. The substrate processing apparatus according to claim 5, wherein The control unit controls the flow path switching unit based on the process recipe, switching between the first state and the second state.

7. The substrate processing apparatus according to claim 5, wherein In the rare gas recovery step, the control unit switches the flow path switching unit to the first state, and in steps other than the rare gas recovery step, switches the flow path switching unit to the second state.

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