Substrate processing apparatus and substrate processing method

Abstract

To properly grasp the progress state of reaction of liquid processing with a processing liquid on a surface of a substrate.SOLUTION: A substrate processing apparatus comprises a holding part, a nozzle, an imaging part, and a control circuit. The holding part rotatably holds a substrate. The nozzle discharges a processing liquid to a surface of the substrate held by the holding part. The imaging part images the surface of the substrate held by the holding part. The control circuit executes liquid processing, imaging processing, detection processing, and measurement processing. In the liquid processing, the processing liquid is discharged from the nozzle toward the surface of the rotating substrate. In the imaging processing, the surface of the substrate in the liquid processing is imaged by the use of the imaging part. In the detection processing, luminance is detected at each of a plurality of positions on the surface of the substrate along a diameter of the substrate based upon the image captured through the imaging processing. In the measurement processing, a reaction time required until the end of the reaction by the processing liquid at each of the plurality of positions on the surface of the substrate based upon the detection result by the detection processing.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] 2. Description of the Related Art Conventionally, there has been known a substrate processing apparatus that processes a substrate such as a semiconductor wafer by rotating the substrate and supplying a processing liquid to the surface of the rotating substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-45616 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can appropriately grasp the progress of a reaction caused by a processing liquid on a surface of a substrate. [Means for solving the problem]

[0005] A substrate processing apparatus according to one aspect of the present disclosure includes a holding unit, a nozzle, an imaging unit, and a control circuit. The holding unit rotatably holds a substrate. The nozzle ejects a processing liquid onto the surface of the substrate held by the holding unit. The imaging unit captures an image of the surface of the substrate held by the holding unit. The control circuit executes a liquid processing, an imaging process, a detection process, and a measurement process. The liquid processing ejects a processing liquid from the nozzle toward the surface of the rotating substrate. The imaging process images the surface of the substrate during the liquid processing using the imaging unit. The detection process detects the brightness at each of a plurality of positions along the radial direction of the substrate on the surface of the substrate based on the image captured by the imaging process. The measurement process measures the reaction time required for the reaction by the processing liquid to complete at each of the plurality of positions on the surface of the substrate based on the detection results of the detection process. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to appropriately grasp the progress of a reaction caused by a processing liquid on a surface of a substrate. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a substrate processing system according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating an example of the configuration of a processing unit according to the embodiment. [Figure 3] FIG. 3 is a block diagram showing the configuration of the control device according to the embodiment. [Figure 4] FIG. 4 is a flowchart showing the procedure of substrate processing performed by the processing unit according to the embodiment. [Figure 5] FIG. 5 is a diagram illustrating an example of sequence information. [Figure 6] FIG. 6 is an explanatory diagram illustrating an example of the detection process performed by the detection unit. [Figure 7] FIG. 7 is a diagram showing an example of a detection result obtained by the detection process. [Figure 8] FIG. 8 is a diagram illustrating an example of reaction distribution information according to the embodiment. [Figure 9] FIG. 9 is an explanatory diagram showing an example of the process of generating average response distribution information by the second generating unit. [Figure 10] FIG. 10 is a flowchart showing the procedure of the reaction time monitoring process according to the embodiment. [Figure 11] FIG. 11 is a flowchart showing the procedure of the optimum sequence information creation process according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments (hereinafter referred to as "embodiments") for carrying out a substrate processing apparatus and a substrate processing method according to the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to these embodiments. Furthermore, the embodiments can be appropriately combined within the scope of not causing any contradiction in the processing content. Furthermore, the same components in the following embodiments will be given the same reference numerals, and redundant explanations will be omitted.

[0009] In addition, for ease of understanding, the drawings referred to below may show an orthogonal coordinate system in which the X-axis, Y-axis, and Z-axis directions are defined as being orthogonal to each other, with the positive Z-axis direction being the vertically upward direction. Also, the direction of rotation around the vertical axis may be referred to as the θ direction.

[0010] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to manufacturing precision, installation precision, etc.

[0011] Conventionally, substrate processing apparatuses are known that process substrates such as semiconductor wafers by rotating the substrates and supplying a processing liquid to the surface of the rotating substrates. For example, such substrate processing apparatuses remove resist films formed on substrates such as semiconductor wafers (hereinafter also referred to as wafers) using a sulfuric acid hydrogen peroxide (SPM) mixture process. The SPM process is performed by supplying an SPM liquid, a processing liquid made by mixing sulfuric acid and hydrogen peroxide, to the resist film on the substrate.

[0012] In liquid processing such as SPM processing, the progress of the reaction (removal of the target substance) caused by the processing liquid on the surface of the substrate is one of the factors that affect the reduction of the amount of processing liquid used and the processing time of the liquid processing.

[0013] Therefore, there is a need for technology that can accurately grasp the progress of reactions caused by processing liquids on the surface of a substrate in liquid processing such as SPM processing.

[0014] (Embodiment) <Outline of the substrate processing system> First, a schematic configuration of a substrate processing system 1 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing a schematic configuration of the substrate processing system 1 according to an embodiment. The substrate processing system 1 is an example of a substrate processing apparatus.

[0015] 1, the substrate processing system 1 includes a loading / unloading station 2 and a processing station 3. The loading / unloading station 2 and the processing station 3 are provided adjacent to each other.

[0016] The loading / unloading station 2 includes a carrier placement section 11 and a transport section 12. On the carrier placement section 11, a plurality of carriers C are placed, each of which accommodates a plurality of substrates, in this embodiment, semiconductor wafers W (hereinafter referred to as wafers W), in a horizontal position.

[0017] The transfer section 12 is provided adjacent to the carrier placement section 11 and includes a substrate transfer device 13 and a transfer section 14. The substrate transfer device 13 includes a wafer holding mechanism that holds the wafer W. The substrate transfer device 13 is capable of moving horizontally and vertically and rotating about a vertical axis, and transfers the wafer W between the carrier C and the transfer section 14 using the wafer holding mechanism.

[0018] The processing station 3 is provided adjacent to the transport part 12. The processing station 3 includes a transport part 15 and a plurality of processing units 16. The processing unit 16 is an example of a substrate processing part. The plurality of processing units 16 are provided side by side on both sides of the transport part 15.

[0019] The transfer section 15 includes a substrate transfer device 17 therein. The substrate transfer device 17 includes a wafer holding mechanism that holds the wafer W. The substrate transfer device 17 is capable of moving in the horizontal and vertical directions and rotating about a vertical axis, and transfers the wafer W between the delivery section 14 and the processing unit 16 using the wafer holding mechanism.

[0020] The processing unit 16 performs a predetermined substrate processing on the wafer W transferred by the substrate transfer device 17. The processing unit 16 will be described in detail later.

[0021] The substrate processing system 1 also includes a control device 4. The control device 4 is, for example, a computer, and includes a control unit 18 and a storage unit 19. The storage unit 19 stores programs that control various processes executed in the substrate processing system 1. The control unit 18 controls the operation of the substrate processing system 1 by reading and executing the programs stored in the storage unit 19.

[0022] Such a program may be recorded on a computer-readable storage medium and installed from that storage medium into the storage unit 19 of the control device 4. Examples of computer-readable storage media include hard disks (HDs), flexible disks (FDs), compact disks (CDs), magnetic optical disks (MOs), and memory cards.

[0023] In the substrate processing system 1 configured as described above, first, the substrate transfer device 13 in the loading / unloading station 2 removes the wafer W from the carrier C placed on the carrier placement unit 11 and places the removed wafer W on the delivery unit 14. The wafer W placed on the delivery unit 14 is then removed from the delivery unit 14 by the substrate transfer device 17 in the processing station 3 and carried into the processing unit 16.

[0024] The wafer W carried into the processing unit 16 is processed by the processing unit 16, and then carried out of the processing unit 16 by the substrate transfer device 17 and placed on the transfer section 14. Then, the processed wafer W placed on the transfer section 14 is returned to the carrier C on the carrier placement section 11 by the substrate transfer device 13.

[0025] <Processing unit configuration> Next, the configuration of processing unit 16 will be described with reference to Fig. 2. Fig. 2 is a schematic diagram showing an example configuration of processing unit 16 according to an embodiment. As shown in Fig. 2, processing unit 16 includes a chamber 20, a liquid processing section 30, a liquid supply section 40, and a collection cup 50.

[0026] Chamber 20 accommodates liquid processing section 30, liquid supply section 40, and collection cup 50. An FFU (Fan Filter Unit) 21 is provided on the ceiling of chamber 20. FFU 21 forms a downflow within chamber 20.

[0027] Liquid processing unit 30 includes a holder 31, a support 32, and a drive unit 33, and performs liquid processing on a placed wafer W. Holder 31 holds wafer W horizontally. Support 32 is a member extending in the vertical direction, and its base end is rotatably supported by drive unit 33, with its tip end supporting holder 31 horizontally. Drive unit 33 rotates support 32 around a vertical axis.

[0028] The liquid processing unit 30 rotates the support column 32 using the drive unit 33, thereby rotating the holder 31 supported by the support column 32, and thereby rotating the wafer W held by the holder 31.

[0029] A gripping portion 31a is provided on the upper surface of a holding portion 31 included in the liquid processing portion 30, and holds the wafer W from the side. The wafer W is held horizontally by the gripping portion 31a while being slightly spaced from the upper surface of the holding portion 31. As a result, the wafer W is held by the holding portion 31 with the surface where substrate processing is performed facing upward. A resist film is formed on the surface (upper surface) of the wafer W.

[0030] The liquid supply unit 40 supplies a processing liquid to the wafer W. The liquid supply unit 40 includes nozzles 41 a, 41 b, arms 42 a, 42 b that horizontally support the nozzles 41 a, 41 b, respectively, and swivel-elevating mechanisms 43 a, 43 b (an example of a moving unit) that swivel and elevate the arms 42 a, 42 b, respectively. The swivel-elevating mechanism 43 a enables the arm 42 a to move the nozzle 41 a within a predetermined movement range above the wafer W.

[0031] The nozzle 41a is, for example, a bar nozzle that extends linearly in the horizontal direction. The nozzle 41a has a length that is shorter than the radius of the wafer W. When the tip end of the nozzle 41a in the longitudinal direction is positioned above the center of the wafer W, the base end of the nozzle 41a in the longitudinal direction is positioned above a position that is spaced from the center of the wafer W toward the outer periphery of the wafer W.

[0032] The nozzle 41 a is connected to an SPM liquid supply unit 44 through an SPM liquid supply path 47 , and discharges the SPM liquid supplied from the SPM liquid supply unit 44 onto the surface of the wafer W.

[0033] The SPM liquid supplied from the SPM liquid supply unit 44 is an example of a processing liquid, and is a chemical liquid produced by mixing sulfuric acid (H2SO4) and hydrogen peroxide (H2O2) at a given ratio (e.g., H2SO4:H2O2=10:1). The SPM liquid is used, for example, in a process for removing a resist film formed on the surface of the wafer W.

[0034] The SPM liquid supply unit 44 includes a sulfuric acid supply source 44a, a valve 44b, a flow rate regulator 44c, a hydrogen peroxide supply source 44d, a valve 44e, a flow rate regulator 44f, and a confluence unit 44g.

[0035] The sulfuric acid supply source 44a supplies sulfuric acid maintained at a given temperature (for example, 120°C) to the confluence 44g through a valve 44b and a flow rate regulator 44c. The flow rate regulator 44c regulates the flow rate of the sulfuric acid supplied to the confluence 44g.

[0036] Hydrogen peroxide supply source 44d supplies hydrogen peroxide solution to confluence 44g via valve 44e and flow rate regulator 44f. Flow rate regulator 44f regulates the flow rate of hydrogen peroxide solution supplied to confluence 44g. Confluence 44g is connected to SPM liquid supply channel 47.

[0037] The SPM liquid produced by mixing sulfuric acid and hydrogen peroxide solution at confluence 44g is supplied to nozzle 41a through SPM liquid supply path 47. Note that the SPM liquid generates heat when the sulfuric acid and hydrogen peroxide solution mix, and so the temperature of the SPM liquid is raised to a temperature (for example, 140°C) higher than that of sulfuric acid by the time it reaches nozzle 41a.

[0038] The nozzle 41b is connected to a rinse liquid supply unit 46. The rinse liquid supplied from the rinse liquid supply unit 46 is used, for example, for a rinse process. Examples of the rinse liquid according to the embodiment include hydrogen peroxide, DIW, ozone water, and diluted ammonia water.

[0039] The rinse liquid supply unit 46 includes a rinse liquid supply source 46a, a valve 46b, and a flow rate regulator 46c. The rinse liquid supply source 46a supplies the rinse liquid to the nozzle 41b. The flow rate regulator 46c regulates the flow rate of the rinse liquid supplied to the nozzle 41b via the valve 46b.

[0040] Recovery cup 50 is disposed to surround holder 31, and collects the processing liquid scattered from wafer W by the rotation of holder 31. A drain outlet 51 is formed at the bottom of recovery cup 50, and the processing liquid collected by recovery cup 50 is discharged from drain outlet 51 to the outside of processing unit 16.

[0041] In addition, an exhaust port 52 for discharging the gas supplied from the FFU 21 to the outside of the processing unit 16 is formed at the bottom of the collection cup 50.

[0042] The processing unit 16 also includes an imaging section 60. The imaging section 60 captures an image of the upper surface of the wafer W. As the imaging section 60, for example, a CCD camera is used.

[0043] <Control device configuration> Next, the configuration of the control device 4 according to the embodiment will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the configuration of the control device 4 according to the embodiment. As shown in Fig. 3, the control device 4 includes a control unit 18 and a storage unit 19.

[0044] The storage unit 19 is realized by, for example, a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, or a storage device such as a hard disk, an optical disk, etc. The storage unit 19 stores recipe information 191, a plurality of pieces of sequence information 192, a plurality of pieces of reaction distribution information 193, and a plurality of pieces of average reaction distribution information 194.

[0045] The control unit 18 is realized, for example, by a CPU (Central Processing Unit) or an MPU (Micro Processing Unit) executing various programs stored in a storage device within the control device 4 using RAM as a work area. The control unit 18 is also realized, for example, by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). That is, in the present disclosure, the control unit 18 is an electronic circuit such as a CPU, FPGA, or ASIC, which executes instruction codes stored in memory or is designed as a circuit for a specific application, thereby performing the various control operations described in this specification. The control unit 18 is an example of a control circuit.

[0046] Control unit 18 includes operation control unit 181, imaging control unit 182, detection unit 183, measurement unit 184, first generation unit 185, second generation unit 186, and selection unit 187, and realizes or executes the functions and actions of the control processing described below. Note that the internal configuration of control unit 18 is not limited to the configuration shown in Fig. 3, and may be any other configuration as long as it is capable of performing substrate processing, etc., which will be described later.

[0047] The operation control unit 181 controls the processing unit 16 based on the recipe information 191 stored in the storage unit 19, thereby causing the processing unit 16 to perform a series of substrate processing operations on the wafer W.

[0048] The recipe information 191 is information that indicates the content and order of substrate processing to be performed by the processing unit 16 .

[0049] An example of substrate processing performed under control of the operation control unit 181 will now be described with reference to Fig. 4. Fig. 4 is a flowchart showing the procedure of substrate processing performed by the processing unit 16 according to the embodiment. The series of substrate processing shown in Fig. 4 is performed in accordance with recipe information 191.

[0050] First, processing unit 16 uses holder 31 of liquid processing unit 30 to hold wafer W, which has been loaded into chamber 20 by substrate transfer device 17 (see FIG. 1). Specifically, processing unit 16 uses multiple grippers 31a to grip an edge of wafer W. Thereafter, processing unit 16 rotates wafer W by rotating holder 31 around a vertical axis using drive unit 33.

[0051] Next, the processing unit 16 performs SPM processing (an example of liquid processing) (step S01). In the SPM processing, first, the rotation lift mechanism 43a of the liquid supply unit 40 moves the nozzle 41a to above the center of the wafer W. Then, the processing unit 16 controls the SPM liquid supply unit 44 and the like to eject the SPM liquid from the nozzle 41a onto the top surface of the rotating wafer W. The SPM liquid supplied to the center of the wafer W spreads over the entire surface of the wafer W as the wafer W rotates. This removes the resist film formed on the top surface of the wafer W.

[0052] Next, processing unit 16 controls rinse liquid supply unit 46 and the like to rinse wafer W with rinse liquid (step S02). Then, processing unit 16 controls processing unit 16 to perform drying processing (e.g., spin drying) on ​​wafer W (step S03). Thereafter, wafer W is unloaded from chamber 20 by substrate transfer device 17. This completes a series of substrate processing steps for one wafer W.

[0053] 3, the description of the operation control unit 181 will continue. In the SPM processing, the operation control unit 181 may cause the processing unit 16 to perform an operation of discharging the SPM solution from the nozzle 41a toward the top surface of the rotating wafer W while moving the nozzle 41a based on sequence information 192 including the movement conditions of the nozzle 41a.

[0054] An example of sequence information 192 will now be described with reference to Fig. 5. Fig. 5 is a diagram showing an example of sequence information 192.

[0055] As shown in FIG. 5, the memory unit 19 stores multiple pieces of sequence information 192, and each piece of sequence information includes items such as "sequence," "total time," "movement speed," and "position" as movement conditions for the nozzle 41a.

[0056] The "sequence" item stores information for identifying the movement conditions of the nozzle 41a in the SPM process. For example, "1" and "2" are stored in the "sequence" item shown in FIG.

[0057] The "total time" item stores information indicating the total time for which the nozzle 41a is moved during the SPM process. For example, the "total time" item shown in FIG. 5 stores "1" and "3." The values ​​"1" and "3" indicate that the process of moving or stopping the nozzle 41a during the SPM process lasts for a total of 1 second and 3 seconds, respectively.

[0058] The "movement speed" item stores information indicating the movement speed of the nozzle 41a during SPM processing. For example, the "movement speed" item shown in FIG. 5 stores "0" and "140." "0" indicates that the nozzle 41a does not move during SPM processing, and "140" indicates that the nozzle 41a moves at 140 m / sec during SPM processing.

[0059] The "position" item stores information indicating a position that defines the movement range of the nozzle 41a above the wafer W. For example, the "position" item shown in FIG. 5 stores "0," "0 → -140," "-140," and "-140 → 0." "0" indicates that the nozzle 41a does not move and remains at the center position of the wafer W. "0 → -140" indicates that the nozzle 41a moves from the center position of the wafer W to a position that is -140 mm away from the center position of the wafer W. "-140" indicates that the nozzle 41a does not move and remains at the center position of the wafer W. "-140 → 0" indicates that the nozzle 41a moves from a position that is -140 mm away from the center position of the wafer W to the center position of the wafer W.

[0060] In the SPM process, the operation control unit 181 causes the processing unit 16 to execute an operation of moving the nozzle 41a based on any one of a plurality of pieces of sequence information 192 shown in Fig. 5. For example, the operation control unit 181 causes the processing unit 16 to execute a movement operation based on the sequence information 192 of sequence "1" shown in Fig. 5. Specifically, the operation control unit 181 performs a process of stopping the nozzle 41a at the center position of the wafer W without moving it for one second, and during that time, the SPM liquid is ejected from the nozzle 41a onto the wafer W.

[0061] 5. Specifically, the operation control unit 181 performs a first movement process and a second movement process for three seconds, during which the SPM liquid is ejected from the nozzle 41a onto the wafer W. The first movement process is a process of moving the nozzle 41a from the center position of the wafer W to a position −140 mm away from the center position of the wafer W toward the peripheral edge of the wafer W. The second movement process is a process of moving the nozzle 41a from a position −140 mm away from the center position of the wafer W toward the peripheral edge of the wafer W to the center position of the wafer W after the nozzle 41a has stopped at a position −140 mm away from the center position of the wafer W toward the peripheral edge of the wafer W.

[0062] Furthermore, in the SPM process, the operation control unit 181 may perform the initial discharge of the SPM liquid from the nozzle 41a onto the wafer W with the nozzle 41a positioned at a position including the center of the wafer W. This suppresses deformation of the peripheral edge of the wafer W due to contact with the high-temperature SPM liquid.

[0063] The imaging control unit 182 images the surface of the wafer W during SPM processing using the imaging unit 60. The imaging control unit 182 images the surface of the wafer W during SPM processing using the imaging unit 60 multiple times per unit time.

[0064] The detection unit 183 detects the brightness at each of a plurality of positions on the surface of the wafer W along the radial direction of the wafer W based on the image captured by the imaging unit 60. Here, an example of the detection process by the detection unit 183 will be described with reference to FIG. 6. FIG. 6 is an explanatory diagram showing an example of the detection process by the detection unit 183. FIG. 6 shows the state of the surface of the wafer W imaged using the imaging unit 60. During the SPM process, regions (hereinafter referred to as "removed regions") from which the resist film has already been removed by the reaction with the SPM liquid and regions (hereinafter referred to as "remaining regions") from which the resist film remains without being removed are generated on the surface of the wafer W. The color of the removed regions is closer to white than the color of the remaining regions. That is, in the captured image of the surface of the wafer W, the removed regions have a relatively high brightness, and the remaining regions have a relatively low brightness. Therefore, the brightness at each of a plurality of positions on the surface of the wafer W along the radial direction of the wafer W indicates the progress of the reaction with the SPM liquid (removal of the resist film). The detection unit 183 detects the brightness at each of a plurality of (here, five) positions P1 to P5 on the surface of the wafer W along the radial direction of the wafer W. Position P1 is the center position of the wafer W, and position P5 is the peripheral position of the wafer W. Positions P2 to P4 are arranged in this order from the center side of the wafer W toward the peripheral side of the wafer W.

[0065] Fig. 7 is a diagram showing an example of the detection results obtained by the detection process. The horizontal axis of time in the graph shown in Fig. 7 indicates the elapsed time from time t0 when the nozzle 41a starts to discharge the SPM liquid onto the wafer W. The vertical axis of brightness in the graph shown in Fig. 7 indicates a value obtained by quantifying the color shading at each of multiple (here, five) positions P1 to P5 (see Fig. 6) on the surface of the wafer W into gradations of 0 to 255. Brightness "0" corresponds to black, and brightness "255" corresponds to white.

[0066] As shown in FIG. 7, for each of the multiple positions P1 to P5 on the surface of the wafer W, the brightness begins to decrease from the initial value toward a value of "0" corresponding to black after a predetermined time has elapsed since the start of discharging the SPM liquid. The brightness then reaches a minimum value. The brightness then increases from the minimum value toward a value of "255" corresponding to white, and stabilizes at a constant final value that is closer to the value of "255" corresponding to white than the initial value. For each of the multiple positions P1 to P5 on the surface of the wafer W, the final brightness value is higher than the initial brightness value. That is, in the detection results shown in FIG. 7, the final brightness value corresponds to the color of the removal region (see FIG. 6), and the initial brightness value corresponds to the color of the remaining region (see FIG. 6).

[0067] Alternatively, the detection unit 183 may create an average image of multiple captured images of the surface of the wafer W captured multiple times per unit time using the imaging unit 60, and detect the luminance using the average image. For example, the detection unit 183 adds up the luminance of each pixel in multiple captured images of the surface of the wafer W for each pixel. The detection unit 183 then creates an average image by dividing the added luminance of each pixel by the number of multiple images of the surface of the wafer W, and uses the created average image to detect the luminance at each of multiple positions on the surface of the wafer W along the radial direction of the wafer W. In the SPM process, vapor is generated from the high-temperature SPM liquid present on the surface of the wafer W. The influence of this SPM liquid vapor may reduce the resolution of the captured image of the surface of the wafer W, thereby reducing the accuracy of luminance detection. In response, by creating an average image of multiple captured images and detecting the luminance from this average image, it is possible to suppress the decrease in luminance detection accuracy due to the influence of the SPM liquid vapor.

[0068] Returning to FIG. 3, the measurement unit 184 measures the reaction time required for the reaction by the SPM liquid to complete for each of the multiple positions on the surface of the wafer W based on the detection results by the detection unit 183. Here, an example of the measurement process by the measurement unit 184 will be described. For example, the measurement unit 184 measures the reaction time for each of the multiple positions P1 to P5 (see FIG. 6) on the surface of the wafer W based on the detection results shown in FIG. 7. Specifically, first, the measurement unit 184 identifies the time point at which the luminance changes in a predetermined manner for each of the multiple positions P1 to P5 on the surface of the wafer W as the time point at which the reaction by the SPM liquid completes. The predetermined change manner includes, for example, a manner in which the color of the remaining region (see FIG. 6) changes toward the color of the removed region (see FIG. 6). For example, the predetermined change manner is a manner in which the luminance increases from a minimum value toward a final value corresponding to the removed region. Note that the predetermined change manner may also be a manner in which the luminance increases from a minimum value to reach a final value corresponding to the removed region. Then, for each of the multiple positions P1 to P5, measurement unit 184 identifies times t1 to t5 at which the brightness begins to rise from the minimum value toward the final value corresponding to the removal region as the time at which the reaction by the SPM liquid ends. By identifying times t1 to t5, measurement unit 184 can measure reaction times T1 to T5 required for the reaction by the SPM liquid to end for each of the multiple positions P1 to P5.

[0069] As described above, in the substrate processing system 1 according to the embodiment, the luminance at each of a plurality of positions on the surface of the wafer W is detected from an image captured during SPM processing, and the reaction time at each of the plurality of positions on the surface of the wafer W is measured based on the luminance. This makes it possible to appropriately grasp the progress of the reaction caused by the SPM liquid on the surface of the wafer W during SPM processing. Therefore, according to the embodiment, the endpoint of the reaction caused by the SPM liquid on the surface of the wafer W can be estimated with high accuracy, which can facilitate a reduction in the amount of SPM liquid used and a shortened processing time for SPM processing.

[0070] The first generation unit 185 continuously performs SPM processing on a plurality of wafers W based on a plurality of sequence information 192 having different movement conditions stored in the storage unit 19. The first generation unit 185 generates reaction distribution information 193 indicating the distribution of reaction times on the surface of each wafer W for each piece of sequence information 192 based on the measurement results of the measurement unit 184 for each wafer W, and stores the generated reaction distribution information 193 in the storage unit 19.

[0071] When SPM processing based on one piece of sequence information 192 for one wafer W is completed, the first generation unit 185 acquires measurement results for the wafer W for which SPM processing has been completed from the measurement unit 184. The first generation unit 185 then plots the reaction times included in the acquired measurement results on a two-dimensional plane with each position along the radial direction of the wafer W as the horizontal axis and the reaction time as the vertical axis. The first generation unit 185 then interpolates the reaction temperatures between adjacent plot points among the multiple plot points using a known interpolation method, thereby generating reaction distribution information 193 that indicates the distribution of reaction times on the surface of each wafer W. The first generation unit 185 generates such reaction distribution information 193 for each piece of sequence information 192 and stores the generated reaction distribution information 193 in the storage unit 19.

[0072] Fig. 8 is a diagram showing an example of reaction distribution information 193 according to the embodiment. Fig. 8 shows an example of multiple pieces of reaction distribution information 193_1 to 193_5 generated when SPM processing based on multiple pieces of sequence information 192 with different movement conditions is performed consecutively on multiple wafers W with a diameter of 300 mm. The horizontal axis of the graph shown in Fig. 8, which represents the wafer position, indicates the distance from the center of the wafer W when the center of the wafer W is set as the reference (0 mm). When there is no need to particularly distinguish between the multiple pieces of reaction distribution information 193_1 to 193_5, they will be referred to as "reaction distribution information 193."

[0073] As shown in FIG. 8, reaction distribution information 193 indicates the reaction time (time until removal of the resist film is completed) at each position (wafer position) along the radial direction of wafer W. In FIG. 8, reaction distribution information 193 corresponding to sequence information 192 of sequence “1” shown in FIG. 5 is shown as “reaction distribution information 193_1.” In addition, in FIG. 9, reaction distribution information 193 corresponding to sequence information 192 of sequence “2” shown in FIG. 5 is shown as “reaction distribution information 193_2.” Similarly, in FIG. 9, reaction distribution information 193 corresponding to multiple pieces of sequence information 192 having different movement conditions of nozzle 41a from sequences “1” and “2” are shown as “reaction distribution information 193_3,” “reaction distribution information 193_4,” and “reaction distribution information 193_5,” respectively. Note that, while FIG. 8 illustrates reaction distribution information 193 in a graph format for ease of understanding, reaction distribution information 193 does not necessarily have to be in a graph format.

[0074] Returning to Fig. 3, second generation unit 186 generates average reaction distribution information 194 by averaging two or more pieces of reaction distribution information 193 corresponding to each combination of two or more pieces of sequence information 192 to be combined, among the plurality of pieces of sequence information 192 stored in storage unit 19.

[0075] Here, an example of the process of generating average response distribution information 194 by second generation unit 186 will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram showing an example of the process of generating average response distribution information 194 by second generation unit 186. Fig. 9 describes a case where average response distribution information 194 is generated by averaging two pieces of response distribution information 193 corresponding to the combination of two pieces of sequence information 192 of sequences "1" and "2" shown in Fig. 5.

[0076] 9, reaction distribution information 193 corresponding to sequence information 192 of sequence "1" shown in Fig. 5 is shown as "reaction distribution information 193_1." Also, in Fig. 9, reaction distribution information 193 corresponding to sequence information 192 of sequence "2" shown in Fig. 5 is shown as "reaction distribution information 193_2."

[0077] 9, the second generation unit 186 generates average reaction distribution information 194 by averaging two pieces of reaction distribution information 193_1 and 193_2 corresponding to the combination of two pieces of sequence information 192 at the ratio of the total time of the two pieces of sequence information 192. That is, since the total time of sequence information 192 of sequence "1" shown in FIG. 5 is 1 second and the total time of sequence information 192 of sequence "2" shown in FIG. 5 is 3 seconds, the reaction time of average reaction distribution information 194 is calculated by the following formula (1). (reaction time of average reaction distribution information 194)=(reaction time of reaction distribution information 193_1)×1 / 4+(reaction time of reaction distribution information 193_2)×3 / 4 (1)

[0078] For each combination of two or more pieces of sequence information 192 to be combined, second generation unit 186 averages two or more pieces of reaction distribution information 193 corresponding to the combination by the ratio of the total time of the combination to generate average reaction distribution information 194. Then, second generation unit 186 stores generated average reaction distribution information 194 in storage unit 19.

[0079] Returning to Fig. 3, the selection unit 187 selects, from all combinations of two or more pieces of sequence information 192 to be combined, a combination that minimizes the maximum value of the reaction time in the average reaction distribution information 194. The selected combination is stored in the storage unit 19 as the sequence information 192 for the next SPM process.

[0080] As described above, in the substrate processing system 1 according to the embodiment, from among all combinations of two or more pieces of sequence information 192 to be combined, the combination that minimizes the maximum reaction time is selected as the sequence information 192 for the next SPM process. This makes it possible to combine two or more pieces of sequence information 192 to create new sequence information 192 that can perform SPM processing in a short time. Therefore, according to the embodiment, it is possible to further reduce the amount of SPM liquid used and shorten the processing time of SPM processing.

[0081] When SPM processing is performed based on new sequence information 192 created by combining two or more pieces of sequence information 192, drying processing is not performed on the wafer W during the SPM processing period. This makes it possible to prevent problems such as a decrease in the temperature of the wafer W during the SPM processing period.

[0082] <Procedure for reaction time monitoring process> Next, a procedure of a reaction time monitoring process executed by the substrate processing system 1 according to the embodiment will be described with reference to Fig. 10. Fig. 10 is a flowchart showing the procedure of the reaction time monitoring process according to the embodiment. The reaction time monitoring process shown in Fig. 10 is executed during SPM processing.

[0083] As shown in FIG. 10, the imaging control unit 182 of the control unit 18 uses the imaging unit 60 to capture an image of the surface of the wafer W during SPM processing (step S101, imaging processing).

[0084] The detection unit 183 of the control unit 18 detects the brightness at each of a plurality of positions on the surface of the wafer W along the radial direction of the wafer W based on the image captured by the imaging unit 60 (step S102, detection process).

[0085] Based on the detection results by the detection unit 183, the measurement unit 184 of the control unit 18 measures the reaction time required for the reaction by the SPM liquid to complete at each of multiple positions on the surface of the wafer W (step S103, measurement process), and ends the reaction time monitoring process.

[0086] <Procedure for creating optimal sequence information> Next, the procedure of the optimum sequence information creation process executed by the substrate processing system 1 according to the embodiment will be described with reference to Fig. 11. Fig. 11 is a flowchart showing the procedure of the optimum sequence information creation process according to the embodiment. The optimum sequence information creation process shown in Fig. 11 may be executed at a predetermined interval.

[0087] Control unit 18 acquires one piece of sequence information 192 from among a plurality of pieces of sequence information 192 stored in storage unit 19 (step S201).

[0088] The control unit 18 performs the SPM process on the wafer W based on the acquired sequence information 192 (step S202).

[0089] When the SPM processing based on the sequence information 192 is completed for the wafer W, the control unit 18 acquires the measurement results for the wafer W for which the SPM processing has been completed from the measurement unit 184. Then, the control unit 18 generates reaction distribution information 193 for the sequence information 192 based on the acquired measurement results (step S203). The control unit 18 stores the generated reaction distribution information 193 in the storage unit 19 in association with the sequence information 192.

[0090] The control unit 18 determines whether all of the sequence information 192 stored in the memory unit 19 has been acquired (step S204). If all of the sequence information 192 has not been acquired (step S204, No), the control unit 18 acquires another piece of sequence information 192 from the plurality of pieces of sequence information 192 stored in the memory unit 19 (step S205). The control unit 18 then returns to the processing of step S202. In this manner, the control unit 18 successively performs SPM processing on the plurality of wafers W based on the plurality of pieces of sequence information 192 stored in the memory unit 19, and generates reaction distribution information 193 for each piece of sequence information 192.

[0091] At this time, the control unit 18 may perform SPM processing continuously on a plurality of wafers W while the discharge flow rate of the SPM liquid from the nozzle 41a is fixed. Alternatively, the control unit 18 may perform SPM processing continuously on a plurality of wafers W while the rotation speed of each of the plurality of wafers W is fixed. This can improve the accuracy of the reaction distribution information 193 generated for each piece of sequence information 192.

[0092] On the other hand, when all of the sequence information 192 has been acquired (Yes at step S204), the control unit 18 sets one of the combinations of two or more pieces of sequence information 192 to be combined as an object to be averaged (step S206).

[0093] The control unit 18 averages two or more pieces of response distribution information 193 corresponding to the combination to be averaged to generate average response distribution information 194 (step S207). The control unit 18 stores the generated average response distribution information 194 in the storage unit 19 in association with the combination to be averaged.

[0094] The control unit 18 determines whether all combinations of two or more pieces of sequence information 192 to be combined have been set as averaging targets (step S208). If all combinations of two or more pieces of sequence information 192 have not been set as averaging targets (step S208, No), the control unit 18 sets another one of the combinations of two or more pieces of sequence information 192 as averaging targets (step S209). The control unit 18 then returns to the processing of step S207. In this way, for each combination of two or more pieces of sequence information 192 to be combined, the control unit 18 generates average reaction distribution information 194 by averaging two or more pieces of reaction distribution information 193 corresponding to that combination.

[0095] On the other hand, if all combinations of two or more pieces of sequence information 192 have been set as targets for averaging (Yes at step S208), the control unit 18 proceeds to step S210.

[0096] The control unit 18 selects, from all combinations of two or more pieces of sequence information 192 to be combined, a combination that minimizes the maximum value of the reaction time in the average reaction distribution information 194 (step S210).

[0097] Control unit 18 determines whether the maximum value of the reaction time in average reaction distribution information 194 corresponding to the selected combination is smaller than a predetermined allowable value (step S211). If the maximum value of the reaction time in average reaction distribution information 194 corresponding to the selected combination is equal to or greater than the allowable value (step S211, No), control unit 18 discards the selected combination (step S212) and ends the optimal sequence information creation process. At this time, control unit 18 may output an alert to a predetermined output device indicating that the optimization of the sequence information has failed.

[0098] On the other hand, if the maximum value of the reaction time in the average reaction distribution information 194 corresponding to the selected combination is smaller than the allowable value (step S211, Yes), the control unit 18 proceeds to step S213. That is, the control unit 18 stores the selected combination in the storage unit 19 as sequence information 192 for the next SPM process (step S213), and ends the optimal sequence information creation process.

[0099] As described above, the substrate processing apparatus (for example, substrate processing system 1) according to the embodiment includes a holder (for example, holder 31), a nozzle (for example, nozzle 41a), an imaging unit (for example, imaging unit 60), and a control circuit (for example, control unit 18). The holder rotatably holds a substrate (for example, wafer W). The nozzle ejects a processing liquid onto the surface of the substrate held by the holder. The imaging unit captures an image of the surface of the substrate held by the holder. The control circuit executes a liquid process (for example, SPM process), an imaging process, a detection process, and a measurement process. The liquid process ejects a processing liquid (for example, SPM liquid) from the nozzle toward the surface of the rotating substrate. The imaging process images the surface of the substrate during the liquid process using the imaging unit. The detection process detects the brightness at each of multiple positions along the radial direction of the substrate on the surface of the substrate based on the images captured by the imaging process. The measurement process measures the reaction time required for the reaction by the processing liquid to be completed at each of a plurality of positions on the surface of the substrate based on the detection results of the detection process.

[0100] Therefore, the substrate processing apparatus according to the embodiment can appropriately grasp the progress of the reaction caused by the processing liquid on the surface of the substrate during liquid processing.

[0101] The disclosed embodiments should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0102] 1. Substrate Processing System 4. Control device 16 Processing Unit 18 Control Unit 19 Memory section 20 Chamber 31 Holding part 40 Liquid supply section 41a Nozzle 41b nozzle 42a Arm 43a Swivel lifting mechanism 44 SPM liquid supply section 50 Collection Cup 60 Imaging unit 181 Motion control section 182 Imaging control unit 183 Detector 184 Measuring section 185 1st generation part 186 Second generation part 187 Selection Section 191 recipe information 192 Sequence Information 193 Reaction distribution information 194 Average response distribution information W wafer

Claims

1. a holder that rotatably holds the substrate; a nozzle that ejects a processing liquid onto the surface of the substrate held by the holder; an imaging unit that images the surface of the substrate held by the holding unit; Control circuit and Equipped with The control circuit a liquid treatment in which the treatment liquid is discharged from the nozzle toward the surface of the rotating substrate; an imaging process of imaging the surface of the substrate during the liquid treatment using the imaging unit; a detection process for detecting brightness at each of a plurality of positions on the surface of the substrate along a radial direction of the substrate based on the captured image obtained by the imaging process; a measurement process for measuring a reaction time required for a reaction caused by the processing liquid to be completed at each of the plurality of positions on the surface of the substrate based on a detection result of the detection process; A substrate processing apparatus that performs the above.

2. The control circuit In the measurement process, a time point at which the luminance detected by the detection process changes in a predetermined manner is identified as a time point at which the reaction by the treatment liquid ends. The substrate processing apparatus according to claim 1 .

3. The control circuit In the imaging process, the surface of the substrate is imaged multiple times per unit time using the imaging unit during the liquid treatment; In the detection process, an average image is created from a plurality of images of the surface of the substrate that are captured a plurality of times per unit time using the imaging unit, and the brightness is detected using the average image. The substrate processing apparatus according to claim 1 .

4. a moving unit that moves the nozzle in a horizontal direction; Furthermore, The control circuit In the liquid processing, the nozzle is moved by controlling the movement unit based on sequence information including a movement condition of the nozzle, and the processing liquid is discharged from the nozzle toward the surface of the substrate that is rotating; The control circuit a first generation process for continuously performing the liquid processing based on the plurality of sequence information pieces, each having a different movement condition, on a plurality of the substrates, and generating, for each of the sequence information pieces, reaction distribution information representing a distribution of the reaction time on the surface of each of the substrates, based on a measurement result of the measurement process on each of the substrates; a second generation process for generating average response distribution information by averaging two or more pieces of response distribution information corresponding to each combination of two or more pieces of sequence information to be combined among the plurality of pieces of sequence information; a selection process of selecting, from all of the combinations to be combined, the combination in which the maximum value of the reaction time in the average reaction distribution information is smallest, as the sequence information for the next liquid treatment; The substrate processing apparatus according to claim 1 , further comprising:

5. The nozzle movement conditions include a position that defines a movement range of the nozzle above the substrate, a total time for moving the nozzle within the movement range, and a movement speed of the nozzle. The substrate processing apparatus according to claim 4 .

6. The control circuit In the second generation process, the average reaction distribution information is generated by averaging two or more pieces of reaction distribution information corresponding to two or more combinations of the sequence information by the ratio of the total time of the two or more combinations. The substrate processing apparatus according to claim 5 .

7. The control circuit In the first generation process, the liquid process is performed continuously on a plurality of the substrates while the discharge flow rate of the processing liquid from the nozzle is fixed. The substrate processing apparatus according to claim 4 .

8. The control circuit In the first generation process, the liquid process is performed continuously on the plurality of substrates while the rotation speed of each of the plurality of substrates is fixed. The substrate processing apparatus according to claim 4 .

9. The control circuit In the liquid processing, the moving unit is controlled based on the sequence information to perform a first moving process of moving the nozzle from the center position of the substrate to the peripheral edge side of the substrate, and a second moving process of moving the nozzle from the peripheral edge side of the substrate to the center position of the substrate. The substrate processing apparatus according to claim 4 .

10. The control circuit In the liquid processing, the first discharge of the processing liquid from the nozzle onto the substrate is performed with the nozzle positioned at a position including the center of the substrate. The substrate processing apparatus according to claim 4 .

11. The treatment liquid is an SPM liquid, which is a mixture of sulfuric acid and hydrogen peroxide. The substrate processing apparatus according to claim 1 .

12. The nozzle is a bar nozzle that extends linearly in the horizontal direction. The substrate processing apparatus according to claim 1 .

13. a liquid processing step of performing a liquid processing on the substrate using a processing unit including a holder that rotatably holds the substrate and a nozzle that discharges a processing liquid onto the surface of the substrate; an imaging step of imaging the surface of the substrate during the liquid treatment using an imaging unit; a detecting step of detecting a luminance value for each of a plurality of positions on the surface of the substrate along a radial direction of the substrate based on the captured image obtained by the imaging step; a measuring step of measuring a reaction time required for a reaction caused by the processing liquid to be completed at each of the plurality of positions on the surface of the substrate based on the detection result of the detecting step; A substrate processing method comprising:

Images