Substrate processing method and substrate processing apparatus

Abstract

To optimize a condition of a purge process by gas analysis.SOLUTION: A substrate processing method executed by a substrate processing apparatus including a processing container that processes a substrate, a gas supply unit that supplies gas into the processing container, an exhaust device that exhausts gas from the processing container, and a gas analyzer that analyzes gas passing through an exhaust pipe connecting the processing container and the exhaust device includes the steps of preparing a substrate in the processing container, supplying processing gas into the processing container and performing processing with the processing gas in the processing container, supplying a purge gas into the processing container to purge the processing gas within the processing container, analyzing process gas passing through the exhaust line with the gas analyzer during the process gas purging step, and determining a condition for the process gas purging step on the basis of the result of analyzing the process gas.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing method and a substrate processing apparatus. [Background technology]

[0002] For example, in Patent Document 1, a cleaning gas is supplied into a chamber of a semiconductor manufacturing device to clean the chamber, and then a confirmation cleaning process is performed to confirm whether deposits inside the chamber have been removed. In the confirmation cleaning process, the concentration of a reaction gas generated by the reaction between the cleaning gas and the deposits adhering inside the chamber during the confirmation cleaning process is measured, and if the reaction gas concentration is equal to or less than a deposit removal judgment value, it is determined that the deposits inside the chamber have been removed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-151356 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can optimize the conditions of the purge process by analyzing the gas. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided a substrate processing method performed by a substrate processing apparatus having a processing vessel for processing a substrate, a gas supply unit for supplying gas into the processing vessel, an exhaust device for exhausting gas from the processing vessel, and a gas analyzer configured to analyze gas passing through an exhaust piping connecting the processing vessel and the exhaust device, the method including: preparing a substrate in the processing vessel; supplying a processing gas into the processing vessel and performing processing using the processing gas in the processing vessel; supplying a purge gas into the processing vessel and purging the processing gas from the processing vessel; analyzing the processing gas passing through the exhaust piping with the gas analyzer during the purging step of the processing gas; and determining conditions for the purging step of the processing gas based on a result of analyzing the processing gas. the step of determining the conditions for the purge step includes: after performing a process using a source gas as the process gas into the processing vessel, supplying a purge gas into the processing vessel and purging the source gas; determining the conditions for the first purge step based on a result of analyzing the source gas during a first purge step; after performing a process using a reactive gas as the process gas into the processing vessel after the first purge step, supplying a purge gas into the processing vessel; and determining the conditions for the second purge step based on a result of analyzing the reactive gas during a second purge step; A method for processing a substrate is provided. [Effects of the Invention]

[0006] According to one aspect, the conditions for the purge step can be optimized by analyzing the gas. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view showing a substrate processing apparatus according to an embodiment. [Figure 2] 1 is a flowchart showing a substrate processing method according to an embodiment. [Figure 3] 5A to 5C are diagrams for explaining optimization of purge conditions in the substrate processing method according to the embodiment; [Figure 4] 1 is a flowchart showing a substrate processing method according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] [Substrate processing equipment] A substrate processing apparatus according to an embodiment of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a cross-sectional view showing the substrate processing apparatus according to the embodiment. Fig. 1 shows a heat treatment apparatus, which is an example of the substrate processing apparatus.

[0010] As shown in FIG. 1, the heat treatment apparatus 1 includes a processing vessel 10, a lid 38, a substrate holder 16, a gas supply unit 60, a gas exhaust unit 71, and a heating unit 90. The processing vessel 10 accommodates a substrate W, such as a semiconductor wafer. The processing vessel 10 has a double-tube structure in which a cylindrical inner tube 12 with a ceiling and an open lower end is coaxially arranged, and a cylindrical outer tube 14 with a ceiling and an open lower end that covers the outside of the inner tube 12. However, the structure of the processing vessel 10 is not limited to this, and the inner tube 12 may not be included. The inner tube 12 and the outer tube 14 are formed of a heat-resistant material such as quartz or silicon carbide (SiC).

[0011] A nozzle accommodating section 18 that accommodates gas nozzles 62, 64, 66 is formed on one side of the inner pipe 12 along the vertical direction. In the present disclosure, a portion of a side wall 20 of the inner pipe 12 protrudes outward, and the protruding space forms the nozzle accommodating section 18. A rectangular slit 22 is formed on the side wall of the inner pipe 12 on the opposite side from the nozzle accommodating section 18 and along the vertical direction.

[0012] The slits 22 are gas exhaust ports formed so as to be able to exhaust gas inside the inner tube 12. The length of the slits 22 is the same as that of the substrate holder 16, or is formed so as to extend in the vertical direction longer than the length of the substrate holder 16. The substrate holder 16 can be accommodated in the processing vessel 10, and holds a plurality of substrates W (e.g., 150 substrates) approximately horizontally at a predetermined interval in the vertical direction.

[0013] The lower end of the processing vessel 10 is supported by a cylindrical manifold 30 made of, for example, stainless steel. A flange 32 is formed at the upper end of the manifold 30. The lower end of the outer pipe 14 is placed on the flange 32, thereby supporting the outer pipe 14. A seal member 34, such as an O-ring, is provided between the flange 32 and the lower end of the outer pipe 14. The seal member 34 maintains the inside of the outer pipe 14 in an airtight state.

[0014] An annular support 36 is provided on the inner wall of the upper portion of the manifold 30. The inner pipe 12 is supported by placing the lower end of the inner pipe 12 on the support 36. A lid 38 is airtightly attached to the opening at the lower end of the manifold 30 via a sealing member 40 such as an O-ring. The lid 38 airtightly closes the opening at the lower end of the processing vessel 10, i.e., the opening of the manifold 30. The lid 38 is made of, for example, stainless steel.

[0015] A rotating shaft 44 is provided in the center of the lid 38, penetrating through a magnetic fluid seal 42. The lower part of the rotating shaft 44 is rotatably supported by an arm 48 of an elevating means 46 such as a boat elevator.

[0016] A rotating plate 50 is provided at the upper end of the rotating shaft 44, and a substrate holder 16 that holds a substrate W is placed on the rotating plate 50 via a quartz heat retention table 52. Therefore, by raising and lowering the lifting means 46, the lid 38 and the substrate holder 16 move up and down as a unit, and the substrate holder 16 can be inserted into and removed from the processing vessel 10.

[0017] The gas supply unit 60 is provided in the manifold 30 and introduces various gases such as source gas, reaction gas, and purge gas into the inner tube 12. The gas supply unit 60 has a plurality of (for example, three) quartz gas nozzles 62, 64, and 66. Each of the gas nozzles 62, 64, and 66 is provided inside the inner tube 12 along its longitudinal direction, and its base end (lower end) is bent into an L-shape and supported so as to penetrate through the manifold 30. The gas nozzles 62, 64, and 66 are installed in the nozzle housing portion 18 of the inner tube 12 along the circumferential direction.

[0018] The gas nozzle 62 supplies a source gas into the processing chamber 10. The gas nozzle 62 has a plurality of gas holes 62A formed at predetermined intervals along its longitudinal direction. The gas holes 62A are formed inside the inner tube 12 and discharge the source gas horizontally into the inner tube 12. The source gas may be, for example, a metal-containing gas or a silicon-containing gas. An example of the metal-containing gas is AlCl3 gas. An example of the silicon-containing gas is dichlorosilane (DCS: SiH2Cl2), hexachlorodisilane (HCD: Si2Cl6), tetrachlorosilane (SiCl4), or trichlorosilane (SiHCl3).

[0019] The gas nozzle 64 supplies a reactive gas that reacts with the source gas into the processing chamber 10. The gas nozzle 64 has a plurality of gas holes 64A formed at predetermined intervals along its longitudinal direction. The gas holes 64A are formed inside the inner tube 12 and discharge the reactive gas horizontally into the inner tube 12. Examples of the reactive gas include an oxidizing gas, a nitriding gas, and a reducing gas. Examples of the oxidizing gas include ozone (O), oxygen (O), water vapor (H), hydrogen and oxygen (H), hydrogen and ozone (H), nitric oxide (NO), nitrous oxide (N), nitrogen dioxide (NO), carbon monoxide (CO), and carbon dioxide (CO). Examples of the nitriding gas and the reducing gas include ammonia (NH), organic amine gas, diazene (N), hydrazine (N), and hydrazine compounds (e.g., monomethylhydrazine (MMH)).

[0020] The gas nozzle 66 supplies a purge gas into the processing vessel 10. The gas nozzle 66 has a plurality of gas holes 66A formed at predetermined intervals along its longitudinal direction. The gas holes 66A are formed inside the inner tube 12 and discharge the purge gas horizontally into the inner tube 12. The purge gas may be, for example, nitrogen (N2) gas or argon (Ar) gas.

[0021] The predetermined intervals between the multiple gas holes 62A, 64A, 66A are set to, for example, the same intervals as the intervals between the substrates W supported by the substrate holder 16. Furthermore, the height positions of the gas holes 62A, 64A, 66A are set so that they are each located midway between vertically adjacent substrates W. This allows the source gas, reaction gas, and purge gas to be efficiently supplied between the substrates W.

[0022] An exhaust port 70 is formed on the upper sidewall of the manifold 30 above the support portion 36. The exhaust port 70 is connected to a space 69 between the inner pipe 12 and the outer pipe 14. Gas inside the inner pipe 12 is discharged through the space 69 and the slit 22, and then exhausted to the outside of the processing vessel 10 through the exhaust port 70. The exhaust port 70 is provided with a gas exhaust unit 71 that exhausts gas inside the processing vessel 10. The gas exhaust unit 71 has an exhaust pipe 72 connected to the exhaust port 70. A pressure control valve (not shown) and an exhaust device 80 are sequentially installed in the exhaust pipe 72 to evacuate the processing vessel 10. The exhaust device 80 has a vacuum pump and exhausts gases such as source gases. A detoxification device 82 is connected to the exhaust device 80. The detoxification device 82 neutralizes the source gases and the like exhausted by the exhaust device 80.

[0023] The exhaust pipe 72 is a main exhaust line, and connects the processing chamber 1 with an exhaust device 80. An exhaust line of a bypass pipe 73 that branches off from the exhaust pipe 72 and bypasses the exhaust pipe 72 is connected to the exhaust pipe 72. A gas analyzer 74 is provided in the bypass pipe 73. In addition, a valve 75 is provided in the bypass pipe 73 on the upstream side of the gas analyzer 74, and a valve 76 is provided on the downstream side of the gas analyzer 74.

[0024] The gas analyzer 74 analyzes the gas passing through the exhaust pipe 72. Specifically, the gas analyzer 74 analyzes process gases such as source gas and reactant gas passing from the exhaust pipe 72 to the bypass pipe 73. For example, the gas analyzer 74 can be a non-dispersive infrared analyzer (NDIR) capable of detecting and quantitatively analyzing gases. The gas analyzer 74 may also be an FT-IR. For example, when the gas analyzer 74 is an NDIR, the gas analyzer 74 analyzes each gas and determines the measured values of the source gas concentration or reactant gas concentration contained in the gas by utilizing the unique absorption wavelength range of each gas. The control unit 2 acquires the source gas concentration or reactant gas concentration signal output from the gas analyzer 74 and determines the degree of replacement of the source gas and reactant gas in the process chamber 10 with the purge gas during the purge process, i.e., the degree of exhaust of the source gas and reactant gas.

[0025] In this way, the gas analyzer 74 analyzes the gas passing through the bypass pipe 73, and the control unit 2 can determine whether the source gas and the reactant gas are being sufficiently exhausted based on the source gas concentration and the reactant gas concentration obtained from the gas analyzer 74. This makes it possible to quickly obtain appropriate values for the purge conditions in the purge process, such as the optimum purge time.

[0026] A cylindrical heating unit 90 is provided on the outer periphery of the outer tube 14 so as to cover the outer tube 14. The heating unit 90 heats the substrate W accommodated in the processing vessel 10.

[0027] The operation of each part of the substrate processing apparatus 1 configured as described above is controlled by a control unit 2. A control program for controlling the operation of each part of the substrate processing apparatus 1 is stored in a memory unit 3. The control unit 2 controls the operation of each part of the substrate processing apparatus 1 in accordance with the control program stored in the memory unit 3. The memory unit 3 also stores recipes that set procedures for executing various processes in the film formation process, such as the adsorption step, oxidation step, and purge step, which will be described later. The control unit 2 executes various processes, such as the film formation process, in accordance with the recipes stored in the memory unit 3. The control unit 2 may be composed of, for example, a computer. The memory unit 3 may be composed of, for example, a memory such as a flexible disk, a compact disk, a hard disk, a flash memory, or a DVD.

[0028] [Recipe optimization] In the deposition process of a metal-containing film such as an AlO film, it is important to form a film with good coverage. To deposit a film with good coverage, it is important to sufficiently discharge (purge out) the source gas and the reaction gas from the processing chamber 10 in the purge process. However, it is difficult to determine whether the source gas and the reaction gas have been purged using current process evaluation methods. For example, it is conceivable to measure the pressure in the exhaust pipe 71 of the substrate processing apparatus 1 using a pressure gauge (not shown) installed in the exhaust pipe 71 to determine whether the source gas and the reaction gas remain in the exhaust pipe 71. However, because the pressure in the exhaust pipe 71 drops, it is difficult to determine whether the processing gas has been purged using this method.

[0029] Therefore, in the past, a temporary recipe was created and a purge time was temporarily set in the temporary recipe, and the control unit 2 controlled the purge time of the processing gas, such as the source gas, according to the temporary recipe.Then, the purge time and other conditions for the purge process were determined by a trial-and-error method in which TEM images of the film resulting from the processing were repeatedly analyzed.As a result, it took a long time to optimize the conditions for the purge process.

[0030] Furthermore, with this method, the optimum purge time and other conditions for the purge process differ depending on differences in the layout (exhaust layout) of the exhaust pipes 72 of the substrate processing apparatus 1 and differences in processing conditions such as the number of substrates processed, etc. Therefore, it was necessary to determine the conditions for the purge process for each substrate processing apparatus 1.

[0031] Therefore, in the substrate processing method according to the present disclosure, a bypass pipe 73 is provided midway through the main exhaust pipe 72, and a gas analyzer 74 is installed in the bypass pipe 73. The gas passing through the bypass pipe 73 is analyzed by the gas analyzer 74 to determine the concentration of the remaining gas in the processing gas, and the conditions for the purge process are optimized based on the results. This allows the purge conditions to be optimized in a shorter time than if the conditions for the purge process were determined by trial and error. Furthermore, this eliminates differences between substrate processing apparatuses 1 with different exhaust layouts, and makes it possible to prevent product defects in any of the substrate processing apparatuses 1.

[0032] [Substrate processing method: Optimizing the conditions of the purge process] A substrate processing method according to an embodiment for optimizing purge conditions will be described below with reference to Figures 2 and 3. Figure 2 is a flowchart illustrating the substrate processing method according to an embodiment for optimizing purge conditions. Figure 3 is a diagram illustrating optimizing purge conditions in the substrate processing method according to an embodiment.

[0033] 1, a film formation method using the substrate processing apparatus 1 will be described taking as an example a case where a metal-containing film such as an AlO film is formed on a substrate W by atomic layer deposition (ALD). In the following description, a control unit 2 controls the operation of each unit of the substrate processing apparatus 1 and controls the substrate processing method.

[0034] (Substrate preparation: Step S1) First, in step S1, a step of preparing substrates W in the processing vessel 10 is executed. The control unit 2 maintains the inside of the processing vessel 10 at a predetermined temperature using the heating unit 90. Next, the control unit 2 places the substrate holder 16 holding multiple substrates W on the lid unit 38, and then raises the lid unit 38 using the lifting means 46 to load the substrates W (substrate holder 16) into the processing vessel 10.

[0035] (Supply of raw material gas: Step S3) Next, in step S3, a source gas, which is an example of a process gas, is supplied into the processing vessel 10, and an adsorption step is performed to perform a film formation process using the source gas. In the adsorption step, the control unit 2 sets the interior of the processing vessel 10 to a predetermined temperature using the heating unit 90. The control unit 2 sets the interior of the processing vessel 10 to a predetermined pressure by exhausting gas from the processing vessel 10 while supplying N2 gas at a predetermined flow rate from the gas nozzle 66 into the processing vessel 10. After the temperature and pressure in the processing vessel 10 have stabilized, the control unit 2 discharges the source gas from the gas hole 62A of the gas nozzle 62 into the inner tube 12. The source gas discharged into the inner tube 12 is heated and pyrolyzed inside the inner tube 12, and the source gas generated by pyrolysis is adsorbed onto the substrate W. The control unit 2 stops the supply of the source gas from the gas hole 62A of the gas nozzle 62 after a predetermined time has elapsed.

[0036] (Supply of purge gas: Step S5) Subsequently, in step S5, a purge step is performed in which a purge gas is supplied into the processing vessel 10 to purge the source gas inside the processing vessel 10. In the purge step, the control unit 2 supplies N2 gas at a predetermined flow rate into the inner pipe 12 from the gas nozzle 66 while discharging the gas inside the inner pipe 12, thereby replacing the source gas inside the inner pipe 12 with N2 gas.

[0037] (Analysis of gas concentration by gas analyzer: Step S7) During the purging process of the raw material gas in step S5, a measurement step is performed in step S7 in which the raw material gas passing through the bypass pipe 73 via the exhaust pipe 72 is analyzed by the gas analyzer 74. In the measurement step, the control unit 2 opens valves 75 and 76. The gas analyzer 74 analyzes the gas passing through the bypass pipe 73. The gas analyzer 74 measures the raw material gas concentration contained in the gas from the gas analysis results. The measured raw material gas concentration is defined as measurement value A.

[0038] (Determination process: step S9) Next, in step S9, the control unit 2 acquires the source gas concentration signal measured by the gas analyzer 74 and compares the measured value A contained in the signal with a preset reference value Sa of the source gas. The control unit 2 determines whether the source gas concentration indicated by the measured value A is lower than the reference value Sa.

[0039] If the control unit 2 determines that the measured value A is equal to or greater than the reference value Sa, the control unit 2 returns to step S5, and continues supplying purge gas and performing analysis by the gas analyzer 74 in steps S5 and S7. If the control unit 2 determines that the measured value A is lower than the reference value Sa, the control unit 2 proceeds to step S11.

[0040] (Determining purge conditions: Step S11) In step S11, a step of determining a purging condition a for the source gas based on the gas analysis results is executed. The control unit 2 determines the purging condition a when the measured value A is lower than the reference value Sa. In the example of FIG. 3, the control unit 2 determines the purging time of the source gas in the purging step as one of the purging conditions a.

[0041] The horizontal axis of FIG. 3 represents time, and the vertical axis represents the measurement value measured by the gas analyzer 74. In the example of FIG. 3, the supply of the raw material gas starts at time t1 and stops at time t2. The supply of the purge gas is carried out continuously. When the measurement by the gas analyzer 74 starts at time t3, the control unit 2 acquires the measurement value A output from the gas analyzer 74.

[0042] When the source gas in the inner pipe 12 is purged, the measured value A of the source gas detected by the gas analyzer 74 decreases. At time t4 when the measured value A falls below the reference value Sa, the control unit 2 determines that the exhaust of the source gas in the inner pipe 12 is complete (the source gas in the inner pipe 12 has been replaced with N2 gas), and determines the source gas purge time in the purge process. The control unit 2 determines the purge time by adding a predetermined margin to the time from time t2 to time t4. FIG. 3 shows an example in which the time from time t4 to time t5 is added as the predetermined margin, and the purge time is determined to be the time from time t2 to time t5. The control unit 2 stores the determined purge time in the recipe as the source gas purge time in the purge process. Note that the stored source gas purge time is an example of condition a of the purge process, and is not limited to this. For example, the control unit 2 may determine the procedure for the source gas purge process, including the purge time, as condition a of the purge process. As a procedure for the purging step, conditions such as the type and flow rate of the purging gas may be determined.

[0043] Based on the determined purge time, the control unit 2 closes the valves 75 and 76 at time t5 and stops the measurement and analysis by the gas analyzer 74. However, the measurement and analysis by the gas analyzer 74 may be continued. In this case, the valves 75 and 76 are left open.

[0044] (Supply of oxidizing gas: Step S13) Next, in step S13, an oxidizing gas, which is an example of a processing gas (reaction gas), is supplied into the processing vessel 10, and a film oxidation step using the oxidizing gas is performed. In the oxidation step, the control unit 2 supplies N2 gas at a predetermined flow rate into the processing vessel 10 from the gas nozzle 66 while controlling the temperature and pressure inside the processing vessel 10 to predetermined values, and supplies the oxidizing gas into the inner tube 12 from the gas hole 64A of the gas nozzle 64. The oxidizing gas supplied into the inner tube 12 reacts with the source gas adsorbed on the substrate W in the adsorption step, oxidizing the film. After a predetermined time has elapsed, the control unit 2 stops the supply of the oxidizing gas from the gas hole 64A of the gas nozzle 64.

[0045] (Supply of purge gas: Step S15) Subsequently, in step S15, a purge step is performed in which a purge gas is supplied into the processing vessel 10 to purge the oxidizing gas inside the processing vessel 10. In the purge step, the control unit 2 supplies N2 gas at a predetermined flow rate into the inner pipe 12 from the gas nozzle 66 while discharging the gas inside the inner pipe 12, thereby replacing the oxidizing gas inside the inner pipe 12 with N2 gas.

[0046] (Analysis of gas concentration by gas analyzer: step S17) During the purging process of the oxidizing gas in step S15, a measurement step is performed in step S17 in which the raw material gas passing through the bypass pipe 73 via the exhaust pipe 72 is analyzed by the gas analyzer 74. In the measurement step, the control unit 2 opens valves 75 and 76. The gas analyzer 74 analyzes the gas passing through the bypass pipe 73. The gas analyzer 74 measures the concentration of the oxidizing gas contained in the gas from the gas analysis results. The measured oxidizing gas concentration is designated as measurement value B.

[0047] (Determination process: step S19) Next, in step S19, the control unit 2 acquires the signal of the oxidizing gas concentration measured by the gas analyzer 74, and compares the measurement value B contained in the signal with a preset reference value Sb of the oxidizing gas. The control unit 2 determines whether the measurement value B is lower than the reference value Sb.

[0048] If the control unit 2 determines that the measured value B is equal to or greater than the reference value Sb, the control unit 2 returns to step S15, and continues supplying purge gas and performing analysis by the gas analyzer 74 in steps S15 and S17. If the control unit 2 determines that the measured value B is below the reference value Sb, the control unit 2 proceeds to step S21.

[0049] (Determining purge conditions: Step S21) In step S21, a step of determining purging condition b for the oxidizing gas based on the gas analysis results is executed. When the measured value B is lower than the reference value Sb, the control unit 2 determines the purging condition b. In the example of Fig. 3, the control unit 2 determines the purging time of the oxidizing gas in the purging step as one of the purging conditions b.

[0050] 3, the supply of oxidizing gas starts at time t5 and stops at time t6. The supply of purge gas is continued. Measurement by the gas analyzer 74 starts at time t7, and the control unit 2 acquires the measurement value B output from the gas analyzer 74.

[0051] When the oxidizing gas in the inner pipe 12 is purged, the measured value B of the oxidizing gas measured by the gas analyzer 74 decreases. At time t8 when the measured value B falls below the reference value Sb, the control unit 2 determines that the exhaust of the oxidizing gas in the inner pipe 12 is complete (the oxidizing gas in the inner pipe 12 has been replaced with N2 gas), and determines the oxidizing gas purge time in the purge process. The control unit 2 determines the purge time by adding a predetermined margin to the time from time t6 to time t8. FIG. 3 shows an example in which the time from time t8 to time t9 is added as the predetermined margin, and the purge time is determined to be the time from time t6 to time t9. The control unit 2 stores the determined purge time in the recipe as the oxidizing gas purge time in the purge process. Note that the stored oxidizing gas purge time is an example of condition b of the purge process, and is not limited to this. For example, the control unit 2 may determine a procedure for the oxidizing gas purge process that includes the purge time as condition b of the purge process. As a procedure for the purging step, conditions such as the type and flow rate of the purging gas may be determined.

[0052] Based on the determined purge time, the control unit 2 closes the valves 75 and 76 at time t9 and stops the measurement and analysis by the gas analyzer 74. However, the measurement and analysis by the gas analyzer 74 may be continued. In this case, the valves 75 and 76 are left open.

[0053] (Determination process: step S23) Next, in step S23, the control unit 2 determines whether this cycle has been performed a set number of times. The set number is an integer equal to or greater than 1. If the control unit 2 determines that this cycle has not been performed the set number of times, the process returns to step S3 and restarts one ALD cycle starting from the adsorption step. If the control unit 2 determines that this cycle has been performed the set number of times in step S23, the control unit 2 supplies N2 gas at a set flow rate into the processing vessel 10 from the gas nozzle 66 while maintaining the interior of the processing vessel 10 at a set temperature using the heating unit 90, thereby cyclically purging the interior of the processing vessel 10 with N2 gas and returning it to atmospheric pressure. Next, the lifting means 46 lowers the lid 38, thereby removing the substrate W (substrate holder 16) from the processing vessel 10 and completing this process.

[0054] As described above, in the substrate processing method according to the embodiment, the gas analyzer 74 is used to analyze and evaluate the gas passing through the bypass pipe 73 during the purge process. This shortens the evaluation time for the source gas purge and the reactant gas purge during the purge process compared to trial-and-error methods. Furthermore, this eliminates differences in the exhaust layout of the exhaust pipe 72 and other components of the substrate processing apparatus 1, allowing the purge time to be set to an optimal value. The optimal purge time varies depending on processing conditions, such as the number of substrates to be processed, the type of processing gas, the type of product substrate, and the type of film to be deposited, in addition to the exhaust layout. Therefore, in accordance with the present substrate processing method, these processing conditions can be taken into consideration and optimal values for the purge process conditions (procedure), such as the purge time, can be determined during evaluation of the substrate processing apparatus 1. Then, when processing product substrates during mass production, as described below, the optimal purge conditions determined during evaluation can be used to process substrates.

[0055] 2 has been described using an example in which an oxidizing gas is supplied, but the present disclosure is not limited thereto and can also be applied to cases in which a nitriding gas or a reducing gas is supplied. The substrate processing method of FIG. 2 may be performed not only during evaluation before mass production, but also during mass production of product substrates. The substrate processing method of the present disclosure may be performed each time a substrate W held by the substrate holder 16 is loaded into the processing vessel 10, or may be performed once for each of multiple loadings of a substrate W.

[0056] [Substrate processing method: Use of determined purge conditions] An example of using the determined purge conditions will be described below with reference to Fig. 4. Fig. 4 is a flowchart showing a substrate processing method according to an embodiment, in which the determined purge conditions are used.

[0057] First, in step S31, the control unit 2 places the substrate holder 16 on the lid portion 38, and then causes the lifting means 46 to raise the lid portion 38 to load the substrate W into the processing vessel 10.

[0058] Next, in step S33, the control unit 2 controls the interior of the container 10 to a predetermined temperature and pressure. The control unit 2 supplies the source gas and N2 gas from the gas nozzles 62 and 66 into the inner tube 12, and executes an adsorption step to adsorb the source gas. After a predetermined time has elapsed, the supply of the source gas is stopped.

[0059] Subsequently, in step S35, the control unit 2 executes a purge step in accordance with purge condition a to purge the source gas in the inner pipe 12. The control unit 2 supplies purge gas into the processing vessel 10 for the determined source gas purge time in accordance with purge condition a, and after the purge time has elapsed, ends the purge process and proceeds to the next step S37.

[0060] In step S37, the control unit 2 supplies oxidizing gas from the gas nozzle 64 into the inner tube 12 to perform the oxidation step. In the oxidation step, the oxidizing gas supplied into the inner tube 12 reacts with the source gas adsorbed on the substrate W, oxidizing the film on the substrate. After a predetermined time has elapsed, the supply of oxidizing gas is stopped.

[0061] Subsequently, in step S39, the control unit 2 executes a purge step in which the oxidizing gas in the inner pipe 12 is purged in accordance with the purge condition b. The control unit 2 supplies the purge gas into the processing vessel 10 for the determined oxidizing gas purge time in accordance with the purge condition b, and after the purging time has elapsed, ends the purge process and proceeds to the next step S41.

[0062] Next, in step S41, the control unit 2 determines whether this cycle has been performed a set number of times. The set number of times is an integer equal to or greater than 1, and may be, for example, 100 times. If the control unit 2 determines that this cycle has not been performed the set number of times, the process returns to step S33 and restarts one cycle of the ALD method starting from the adsorption step. If the control unit 2 determines in step S41 that this cycle has been performed the set number of times, the process vessel 10 is cyclically purged with N2 gas to return the pressure inside the process vessel 10 to normal pressure. Next, the lifting means 46 lowers the lid 38, thereby unloading the substrate W (substrate holder 16) from the process vessel 10, and this process ends.

[0063] As described above, according to the substrate processing method and substrate processing apparatus of this embodiment, the conditions of the process gas (source gas, oxidizing gas) purge step, such as the purge time of the process gas, can be optimized by analyzing the gas passing through the bypass piping 73.

[0064] 2 and 4 have been described using a film formation process on a substrate W as an example, but the method is not limited thereto and can also be used for cleaning the processing vessel 10. In this case, a cleaning gas is supplied into the processing vessel, and then a purge gas such as N2 gas is supplied to perform a purge step. At this time, the gas passing through the bypass piping 73 is analyzed by the gas analyzer 74, and the conditions for the cleaning gas purge process are determined based on the analysis results.

[0065] The substrate processing method and substrate processing apparatus according to the presently disclosed embodiments should be considered to be illustrative in all respects and not restrictive. The embodiments can be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above embodiments can be configured in other ways as long as they are not inconsistent, and can be combined as long as they are not inconsistent.

[0066] In the above embodiment, the substrate processing apparatus is described as a batch-type apparatus that processes multiple substrates at once, but this is not limited thereto. The substrate processing apparatus may also be a single-wafer-type apparatus that processes substrates one by one. Furthermore, for example, the substrate processing apparatus may be a multi-wafer substrate processing apparatus that has multiple mounting tables in a single processing chamber. Furthermore, for example, the substrate processing apparatus may be a semi-batch-type apparatus that processes multiple substrates placed on a turntable in a processing chamber by rotating the turntable and passing the substrates sequentially through an area where a first gas is supplied and an area where a second gas is supplied.

[0067] The substrate processing apparatus according to the present disclosure may be an apparatus for processing a substrate without using plasma, or an apparatus for processing a substrate using plasma. [Explanation of symbols]

[0068] 1. Heat treatment equipment 2. Control section 10 Processing container 60 Gas supply unit 71 Gas exhaust section 72 Exhaust piping 73 Bypass piping 74 Gas analyzer 80 Exhaust system

Claims

1. a processing vessel for processing a substrate; a gas supply unit that supplies a gas into the processing chamber; an exhaust device that exhausts gas from the processing vessel; a gas analyzer configured to analyze gas passing through an exhaust pipe connecting the processing vessel and the exhaust device; A substrate processing method performed by a substrate processing apparatus having providing a substrate in the processing chamber; supplying a processing gas into the processing vessel and performing processing with the processing gas in the processing vessel; supplying a purge gas into the processing vessel to purge the processing gas in the processing vessel; analyzing the process gas passing through the exhaust line with the gas analyzer during the process gas purging step; and determining conditions for a purging step of the processing gas based on the results of analyzing the processing gas; The step of determining the conditions for the purge step includes: performing a process using a source gas as the process gas in the processing vessel; supplying a purge gas into the processing vessel; and determining the conditions for the first purge step based on a result of analyzing the source gas during a first purge step in which the source gas is purged; a second purge step for purging the reactive gas from the processing vessel; a second purge step for purging the reactive gas from the processing vessel; and a second purge step for purging the reactive gas from the processing vessel;

2. the gas analyzer is provided in a bypass pipe that bypasses the exhaust pipe, The step of analyzing the processing gas includes analyzing the processing gas passing through the exhaust pipe and the bypass pipe. The substrate processing method according to claim 1 .

3. The step of determining the conditions for the purge step includes determining a purge time for purging the processing gas depending on when the analysis value of the processing gas falls below a preset reference value. The substrate processing method according to claim 1 or 2.

4. the condition for the raw material gas purging step is a purging time for the raw material gas, The condition of the reaction gas purging step is a purging time of the reaction gas. The substrate processing method according to any one of claims 1 to 3.

5. The step of preparing a substrate includes preparing a new substrate; The step of performing the treatment with the treatment gas includes supplying a treatment gas into the treatment vessel and treating the new substrate with the treatment gas in the treatment vessel; The step of purging the processing gas includes supplying a purge gas into the processing vessel and purging the processing gas according to the determined conditions for the purge step of the processing gas. The substrate processing method according to any one of claims 1 to 4.

6. a processing vessel for processing a substrate prepared therein; a gas supply unit that supplies a gas into the processing chamber; an exhaust device that exhausts gas from the processing vessel; a gas analyzer configured to analyze gas passing through an exhaust pipe connecting the processing vessel and the exhaust device; A substrate processing apparatus having a control unit, The control unit supplying a processing gas into the processing vessel and performing processing with the processing gas in the processing vessel; supplying a purge gas into the processing vessel to purge the processing gas in the processing vessel; analyzing the process gas passing through the exhaust line with the gas analyzer during the process gas purging step; determining conditions for a purging step of the processing gas based on the results of analyzing the processing gas; The step of determining the conditions for the purge step includes: performing a process using a source gas as the process gas in the processing vessel; supplying a purge gas into the processing vessel; and determining the conditions for the first purge step based on a result of analyzing the source gas during a first purge step in which the source gas is purged; a substrate processing apparatus that, after the first purge step, performs processing using a reactive gas as the processing gas in the processing vessel, supplies a purge gas into the processing vessel, and determines conditions for the second purge step based on results of analyzing the reactive gas during a second purge step in which the reactive gas is purged.

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