Substrate processing method, substrate processing device, semiconductor device manufacturing method, and program

Abstract

Provided is a technique with which it is possible to detect lateral displacement of a substrate on a boat by using a mapping sensor provided in a transfer machine. Provided is a technique comprising: (a) a step for placing substrates in multiple levels on a boat by means of a substrate transfer machine provided with an end effector for gripping the substrates; and (b) a step for controlling a boat rotator that rotates the boat, and a mapping sensor having an optical axis in a plane perpendicular to the axis of rotation of the boat rotator, to attempt to detect the substrates held by the boat from at least two directions including a direction different from the direction in which the substrates are transferred to the boat.

Description

Substrate processing method, substrate processing apparatus, method for manufacturing semiconductor device, and program

[0001] The present disclosure relates to a substrate processing method, a substrate processing apparatus, a method for manufacturing a semiconductor device, and a program.

[0002] After the charging of the wafer (also referred to as a substrate) to the boat (also referred to as a substrate support), the sensor of the wafer abnormality detection device may detect the ejection of the wafer from the boat (see International Publication No. 2019 / 012465).

[0003] International Publication No. 2019 / 012465

[0004] When an operation of lifting the substrate from the boat during film formation (also referred to as substrate pickup processing) is performed, the substrate may be displaced horizontally (lateral displacement) in the boat. The lateral displacement of the substrate in the boat is more likely to cause a conveyance error than the front and rear displacements.

[0005] The present disclosure provides a technique capable of detecting the lateral displacement of a substrate on a boat with a mapping sensor provided in a transfer machine.

[0006] According to one aspect of the present disclosure, there is provided a technique including: (a) a step of placing substrates on a boat in multiple stages by a substrate transfer machine including an end effector that grips the substrates; and (b) a step of controlling a boat rotator that rotates the boat and a mapping sensor having an optical axis in a plane perpendicular to the rotation axis of the boat rotator to attempt to detect the substrates held on the boat from at least two directions including a direction different from the direction of transferring the substrates to the boat.

[0007] According to the present disclosure, it becomes possible to detect the lateral displacement of a substrate on a boat with a mapping sensor provided in a transfer machine.

[0008] Figure 1 is a longitudinal cross-sectional view showing a schematic configuration of a substrate processing apparatus preferably used in one embodiment of the present disclosure. Figure 2A is a diagram illustrating an example configuration of a substrate transfer machine preferably used in one aspect of the present disclosure. Figure 2B is a diagram illustrating an example configuration of a boat preferably used in one aspect of the present disclosure. Figure 3 is a cross-sectional view illustrating an example configuration of a seal cap and its surroundings preferably used in one aspect of the present disclosure. Figure 4 is a diagram illustrating an example configuration of a controller preferably used in one aspect of the present disclosure. Figure 5 is a top view illustrating the optical axis of a mapping sensor preferably used in one aspect of the present disclosure. Figure 6 is a flowchart of a first mode of lateral displacement detection preferably used in one aspect of the present disclosure. Figure 7 is a flowchart of a second mode of lateral displacement detection preferably used in one aspect of the present disclosure. Figure 8 is a flowchart of a third mode of lateral displacement detection preferably used in one aspect of the present disclosure. Figure 9 is a diagram showing an example of a flow of a substrate processing method preferably used in the present disclosure.

[0009] Hereinafter, one aspect of this disclosure will be described with reference mainly to Figures 1 to 9. Note that the drawings used in the following description are all schematic, and the dimensional relationships and ratios of the elements shown in the drawings do not necessarily correspond to reality. Furthermore, the dimensional relationships and ratios of the elements do not necessarily correspond between multiple drawings.

[0010] (Overview of Substrate Processing Apparatus) The substrate processing apparatus 1 described in this embodiment is used in the manufacturing process of semiconductor devices. It places the substrate to be processed in a processing chamber and heats the substrate with a heater to perform processing (heat treatment). More specifically, it is a vertical substrate processing apparatus that processes multiple substrates simultaneously while they are stacked vertically at predetermined intervals.

[0011] Examples of substrates processed by substrate processing equipment include semiconductor wafer substrates (wafer cassettes, simply referred to as wafers) on which semiconductor devices are fabricated. Examples of heat treatments performed by substrate processing equipment include oxidation, diffusion, annealing, reflow, sintering, film formation by thermal CVD (Chemical Vapor Deposition) reaction, and film quality improvement (treatment) treatments.

[0012] (1) Components of the substrate processing apparatus The overall structure of the substrate processing apparatus 1 will be explained using Figure 1. Figure 1 shows the main parts of the substrate processing apparatus.

[0013] The substrate processing apparatus 1 is equipped with a housing 2. A sealed substrate container, the pod 3, is loaded into and unloaded from the substrate processing apparatus 1 by an in-process transport device (not shown).

[0014] A sub-enclosure 4 is provided at the lower rear end of the enclosure 2. A pair of wafer loading / unloading ports 7 are provided on the front wall 5 of the sub-enclosure 4, arranged vertically in two rows, upper and lower, for loading and unloading wafers 6 into and out of the sub-enclosure 4. Pod openers 8 are provided for each of the upper and lower wafer loading / unloading ports 7.

[0015] The pod opener 8 comprises a mounting base 9 on which the pod 3 is placed, and an opening / closing mechanism 11 for opening and closing the lid of the pod 3. The pod opener 8 is configured to open and close the wafer entrance / exit of the pod 3 by opening and closing the lid of the pod 3, which is placed on the mounting base 9, using the opening / closing mechanism 11.

[0016] The sub-enclosure 4 constitutes an airtight transfer chamber (loading chamber, loading area) 12, separated from the space where the pod opener 8 is located. A substrate transfer machine (also simply called a transfer machine) 13 is installed in the front area of ​​the transfer chamber 12. The transfer machine 13 is equipped with a required number of wafer mounting plates (substrate gripping parts) 14 for holding wafers 6 (five in the figure). The wafer mounting plates 14 are capable of moving linearly horizontally (for example, linearly in the X direction), rotating horizontally (for example, rotating in the Y direction), and moving vertically (for example, moving vertically in the V direction). The transfer machine 13 is configured to load (charge) and discharge (discharge) wafers 6 onto a boat 15, which serves as a substrate holder, located in the transfer chamber 12. The wafer mounting plates 14 are also called hands, end effectors, chucks, forks, or tweezers, and can be composed of, for example, five mounting plates.

[0017] A vertical processing furnace 16 is installed above the transfer chamber 12. The processing furnace 16 has a processing chamber 17 inside, and the lower end of the furnace opening near the bottom of the processing chamber 17 is open and can be opened and closed by a furnace opening shutter (not shown). The processing chamber 17 heat-treats the wafers 6 that are held in the boat 15.

[0018] A boat elevator 18 for raising and lowering the boat 15 is installed on the side of the sub-enclosure 4. A seal cap 19, which serves as a lid, is horizontally attached to an arm (not shown) connected to the lifting platform of the boat elevator 18. The seal cap 19 vertically supports the boat 15 and allows the furnace opening to be airtightly closed when the boat 15 is loaded into the processing furnace 16. The transfer chamber 12 is adjacent to the processing chamber 17 and holds the boat 15 between it and the processing chamber 17, and allows for the loading and unloading of wafers 6 together with the boat 15. The boat 15 is configured to hold multiple wafers 6 (for example, 50 to 175 wafers) in a horizontal position in multiple stages, with the wafers 6 aligned at their centers. As shown in Figure 2, the boat 15 is equipped with support columns 15a to 15c as columns for holding the wafers 6. Grooves (slots) for holding the wafers 6 are provided in the support columns 15a to 15c. In addition, at least the outer circumferential side surfaces of the support columns 15a to 15c are cylindrical.

[0019] On the side of the seal cap 19 opposite the processing chamber 17, a rotating mechanism 21 is installed that rotates the boat 15 around a central axis corresponding to the center of the wafer 6. The rotating shaft of the rotating mechanism 21, which acts as a boat rotator, passes through the seal cap 19 and is connected to the boat 15. The rotating mechanism 21 is a rotational drive unit that rotates the boat 15, and is configured to rotate the wafer 6 by rotating the boat 15 within the processing chamber 17.

[0020] A clean unit (not shown) is installed on the side opposite to the boat elevator 18 (the second side 4b of the sub-casing 4) (the first side 4a of the sub-casing 4). The clean unit consists of a supply fan and a dust filter to supply clean air, which is purified air or an inert gas. The first side 4a of the sub-casing 4 (i.e., the first side of the transfer chamber 12) has a clean air outlet. A notch alignment device (not shown), which serves as a substrate alignment device to align the circumferential position of the wafer 6, may be installed between the transfer machine 13 and the clean unit.

[0021] The clean air blown out from the clean unit flows through the notch alignment device, the transfer machine 13, and the boat 15. A portion of it is then drawn in by a local exhaust duct (or common exhaust duct) provided on the second side of the transfer chamber 12 and exhausted to the outside of the housing 2 through the exhaust duct. The second side 4b of the sub-housing 4 (i.e., the second side of the transfer chamber 12) has an exhaust port. Another portion is blown back into the transfer chamber 12 by the clean unit.

[0022] An example configuration of the transfer machine 13 will be explained using Figures 2 and 5. In Figures 2 and 5, the transfer machine 13 will be referred to as the transfer machine 36, and the wafer mounting plate 14 will be referred to as the wafer mounting plate 37. Figure 2 shows the state when the wafer 6 is transferred to the boat 15 by the transfer machine 36. That is, the wafer mounting plate (end effector) 37 of the transfer machine 36 faces the support pillars 15a and 15c of the boat 15.

[0023] The transfer machine 36 includes a guide 360 ​​provided along the vertical direction (Z-axis direction), a Z-axis drive unit 361, a Y-axis drive unit 362, an X-axis drive unit 363, and a V-axis drive unit 364. Each of the drive units 361 to 364 can be referred to as a drive system.

[0024] The Z-axis drive unit 361 is provided at the lower or upper end of the guide 360 ​​in order to move the mount 360a along the guide 360 ​​in the vertical direction (Z-axis direction, vertical direction).

[0025] The Y-axis drive unit 362 is mounted on the upper surface of the mount 360a so as to be rotatable in the Y-axis direction, in order to rotate it clockwise or counterclockwise horizontally (rotate around the Y-axis) while supporting the X-axis and Y-axis of the X-axis drive unit 363 so as to be perpendicular to each other. The range of rotation is usually sufficient to be about 180 degrees, since the pod 3 is positioned between the direction of the boat 15 and the opposite direction when viewed from the Y-axis.

[0026] The X-axis drive unit 363 is provided integrally with or inside the Y-axis drive unit 362 in order to move back and forth horizontally (in the X-axis direction) while supporting the V-axis drive unit 364. The X-axis is defined as the direction in which the wafer mounting plate 37 moves so as to protrude from the Y-axis drive unit 362 in order to enter the boat 15 or pod 3, which is called "forward".

[0027] The V-axis drive unit 364 is provided on the X-axis drive unit 363 and is configured to horizontally support five wafer mounting plates 37 while allowing their spacing to be adjusted in the Z-axis direction.

[0028] As a result, the transfer machine 36 can remove the wafer 6 from the pod 3 using the wafer mounting plate 37 and load (charge) it into the boat 15. After any processing is performed on the wafer 6 in the processing furnace 16, the transfer machine 36 can remove (discharge) the wafer 6 from the boat 15 using the wafer mounting plate 37 and load it into the pod 3. The Y-axis drive unit 362 has an external shape such that its turning radius is equal to or slightly larger than the minimum turning radius of the wafer mounting plate 37 and the V-axis drive unit 364 around the Y axis. For example, the length of the Y-axis drive unit 362 in the X-axis direction is equal to or slightly larger than the combined length of the wafer mounting plate 37 and the V-axis drive unit 364, and it has a side surface parallel to the X-axis.

[0029] The transfer machine 36 further includes sensor rods 50a and 50b as arms, provided on both sides of the Y-axis drive unit 362, and forward / backward drive units 365a and 365b that move the sensor rods 50a and 50b in the X-axis direction. In Figure 2A, only the sensor rod 50a provided on the first side of the Y-axis drive unit 362 is shown, but the sensor rod 50b and the forward / backward drive unit 365b that moves the sensor rod 50b in the X-axis direction are provided on the second side of the Y-axis drive unit 362 (the second side opposite the first side), which is not shown (see Figure 5).

[0030] The sensor rods 50a and 50b extend upward along both sides of the Y-axis drive unit 362 to approximately the same height as either of the wafer mounting plates 37, and are bent at approximately a right angle to the rear of the X-axis, in the direction opposite to the mounting direction of the wafer mounting plate 37 to the X-axis drive unit 363. The sensor rods 50a and 50b hold the fiber sensors 51a and 51b and the injectors 52a and 52b, which serve as mapping sensors.

[0031] The tips of the sensor rods 50a and 50b are equipped with light transmitting and receiving units 54a and 54b of fiber sensors 51a and 51b, respectively. The fiber sensors 51a and 51b are a pair of transmissive sensors in which one transmits light and the other receives it, and they can be arranged so that the optical path (optical axis) formed between the light transmitting and receiving units 54a and 54b is parallel to the tangent to the wafer 6. For example, the light transmitting and receiving unit 54a of fiber sensor 51a is one of the light transmitting and receiving units, and the light transmitting and receiving unit 54b of fiber sensor 51b is the other of the light transmitting and receiving units. The fiber sensors 51a and 51b perform mapping to count the number of wafers 6 loaded in the pod 3 or boat 15, and to detect normal or abnormal conditions such as wafers flying out, by detecting the interruption of the optical path. When the sensor rods 50a and 50b move forward, the optical axis remains aligned and horizontal. The sensor rods 50a and 50b may be connected through the Y-axis drive unit 362 so as to interlock with each other, in which case only one of the forward / backward drive units 365a and 365b is required.

[0032] Furthermore, the forward and backward drive units 365a and 365b are positioned on both sides of the Y-axis drive unit 362 and support the sensor rods 50a and 50b so that they can move in the X-axis direction between the protruding position and the retracted position. That is, the wafer mounting plate 37 and the sensor rods 50a and 50b are positioned back-to-back with respect to the Y-axis drive unit 362 and can move independently of each other along the X-axis. The sensor rods 50a and 50b are movable along the longitudinal direction (up and down direction, Z direction) of the support columns 15a to 15c of the boat 15 by the Z-axis drive unit 361.

[0033] As a result, the transfer machine 36 can perform mapping of the wafer 6 inside the pod 3 using fiber sensors 51a and 51b. Furthermore, the transfer machine 36 can perform mapping of the wafer 6 inside the boat 15 using fiber sensors 51a and 51b.

[0034] The injectors 52a and 52b are arranged along the sensor rods 50a and 50b. A gas supply pipe 60 is connected to at least one of the injectors 52a and 52b via a flexible pipe 61 or the like. The gas supply pipe 60 is equipped with a mass flow controller (MFC) 62 and a valve 63 as an on / off valve, in order from the upstream side of the gas flow. Clean gas is supplied to the injectors 52a and 52b as a cleaning gas. As the clean gas, for example, nitrogen (N) which constitutes the atmosphere in the transfer chamber 12 is used. ２ ) Gas can be used. The flexible piping 61 is laid out as appropriate, passing through the guide 360 ​​or its cover, the mount 360a, and the Y-axis drive unit 362, and has the flexibility not to hinder the operation of the Y-axis drive unit 362 or the forward / backward drive units 365a, 365b (described later).

[0035] Assuming that a gas supply pipe 60 is connected to the injector 52a, the injector 52a is provided for cleaning the support columns 15a to 15c of the boat 15. In the cleaning state, no wafers 6 are loaded into the boat 15. Figure 2A shows an enlarged example of the configuration of the sensor rod 50a. The sensor rod 50b has a similar configuration to the sensor rod 50a.

[0036] As shown in Figure 2A, the injection holes 53a and 53b of the injectors 52a and 52b are positioned at the tip ends of the sensor rods 50a and 50b. In other words, the injection holes 53a and 53b of the injectors 52a and 52b are attached to the light transmitting and receiving sections 54a and 54b of the fiber sensors 51a and 51b. The injector 52a is a pipe bent into a shape similar to that of the sensor rod 50a, with its horizontal section positioned below the sensor rod 50a. The injector 52a has injection holes 53a on its side near the tip, and the other end is connected to the flexible piping 61. The optical window 55a and injection holes 53a of the light transmitting and receiving section 54a are positioned side by side, facing substantially the same direction.

[0037] Next, an example of the configuration of the boat 15 will be described using Figure 2B. Figure 2B is a diagram illustrating an example of the configuration of a boat suitably used in one embodiment of the present disclosure. As shown in Figure 2B, the boat 15 as a substrate support includes a main boat 217a and a sub-boat 217b, and is configured so that the main boat 217a and the sub-boat 217b can be combined. The main boat 217a is depicted in the lower left of Figure 2B, and the sub-boat 217b is depicted in the upper left of Figure 2B. Note that the main boat 217a can also be simply referred to as boat 217a. The support columns 15a, 15b, and 15c of the boat 15 in Figure 2A are shown in Figure 2B as the support columns 300a, 300b, and 300c of the main boat 217a.

[0038] The main boat 217a has a plurality of first support parts 321 configured to support multiple wafers 6, for example 25 to 200 wafers, in a horizontal position and aligned vertically with their centers aligned, in multiple stages, that is, arranged with spacing between them. In other words, the main boat 217a has at least one first support part 321 for each of the plurality of substrates (wafers), that is, for each substrate. The main boat 217a is made of a heat-resistant material such as quartz or SiC. At the bottom of the main boat 217a, a heat-insulating plate 218 made of a heat-resistant material such as quartz or SiC is supported in multiple stages.

[0039] The main boat 217a includes a plurality of fixed support columns 300a, 300b, and 300c (in this case, three fixed support columns) that extend in a direction substantially perpendicular to the wafer 6 and each is provided with a first support portion 321, and a first connecting portion 31 that fixes the plurality of fixed support columns 300a-300c to each other. The first connecting portion 31 includes a first bottom plate 31a that fixes the vicinity of the lower ends of the plurality of fixed support columns 300a-300c to each other, and a first upper plate 31b that fixes the vicinity of the upper ends of the plurality of fixed support columns 300a-300c to each other. Each of the plurality of fixed support columns 300a-300c is provided with a plurality of first support portions 321. The main boat 217a is housed inside the processing chamber 17, and the substrate 6 placed on the main boat 217a is processed inside the processing chamber 17.

[0040] The sub-boat 217b has a plurality of second support parts 422 configured to support multiple wafers 6, for example 25 to 200 wafers, in a horizontal position and aligned vertically with their centers aligned, in a multi-stage arrangement, that is, arranged with spacing between them. The plurality of second support parts 422 are provided so as to be movable in the vertical direction relative to the main boat 217a. The sub-boat 217b is made of a heat-resistant material such as quartz or SiC.

[0041] As shown in Figure 2B, the sub-boat 217b includes a plurality of movable support columns 400a, 400b, 400c, and 400d (in this case, four movable support columns) that extend in a direction substantially perpendicular to the wafer 6 and each is provided with a second support portion 422, and a second connecting portion 41 that fixes the plurality of movable support columns 400a-400d to each other. The second connecting portion 41 includes a second bottom plate 41a that fixes the vicinity of the lower ends of the plurality of movable support columns 400a-400d to each other, a second upper plate 41b that fixes the vicinity of the upper ends of the plurality of movable support columns 400a-400d to each other, and an intermediate plate 41c that fixes the vicinity of the middle of the plurality of movable support columns 400a-400d to each other (the portion between the upper and lower ends). Each of the plurality of movable support columns 400a-400d is provided with a plurality of second support portions 422. The second upper plate 41b and second bottom plate 41a of the secondary boat 217b are configured to be fitted between the first upper plate 31b and first bottom plate 31a of the main boat 217a. Multiple movable support columns 400a-400d are arranged to rotate together with the main boat 217a on the outer circumference of the base plate 6 supported by the main boat 217a.

[0042] The second bottom plate 41a is a plate with a shape that allows it to be stably placed on the first bottom plate 31a. Each of the second bottom plate 41a, the second top plate 41b, and the intermediate plate 41c is provided with a notch 42 through which a plurality of fixed support columns 300b are inserted on the inside. In other words, the sub-boat 217b has a plurality of movable support columns 400a-400d, each provided with a second support portion 422, and a second connecting portion 41 that fixes the plurality of movable support columns 400a-400d to each other. The sub-boat 217b is provided so as to be movable in the vertical direction relative to the main boat 217a within a range where the upper and lower ends are restricted.

[0043] On the right side of FIG. 2B, a horizontal cross-sectional view of the main boat 217a is drawn on the lower side, and a horizontal cross-sectional view of the sub-boat 217b is drawn on the upper side. Here, they are drawn side by side vertically so that the center in the left-right direction of the main boat 217a coincides with the center in the left-right direction of the sub-boat 217b. In the sub-boat 217b, the center of gravity CT1 of the second coupling part 41 (41a, 41b, 41c) itself is biased toward the substrate take-out direction (also referred to as the substrate loading / unloading direction) 450 side from the rotation center axis 451. Also, in the sub-boat 217b, the center of gravity CT2 of the four movable support columns 400a - 400d is biased toward the side opposite to the substrate take-out direction 450. The overall center of gravity CT3 of the sub-boat 217b is configured to be approximately on the rotation center axis 451. Also, the overall center of gravity of the main boat 217a is configured to be on the rotation center axis 451. Thereby, since the center of gravity of the boat 15 formed by combining the main boat 217a and the sub-boat 217b is configured to be on the rotation center axis 451, the combined boat 15 can be stably rotated about the rotation center axis 451.

[0044] The drive device 100 as a lift mechanism described later is configured to be able to lift the second support part 422 relatively upward and float the substrate 6 from at least one first support part 321. Specifically, in the configuration in which the main boat 217a and the sub-boat 217b are combined, the sub-boat 217b is configured to be movable in the vertical direction within a range where the upper and lower ends are restricted with respect to the main boat 217a. And the drive device 100 moves the sub-boat 217b upward within a range where the upper and lower ends are restricted with respect to the main boat 217a during the film formation process to lift a plurality of wafers 6 simultaneously. Thus, by lifting the substrate 6 in the processing chamber 17, it is possible to shorten the film formation time and improve the film quality. Also, when performing the operation of lifting a plurality of wafers 6 simultaneously under reduced pressure in the processing chamber 17, the throughput is dramatically improved. Also, since the substrate support 15 (217a, 217b) is not moved to the transfer chamber 12, oxidation of the substrate support 15 in the transfer chamber 12 is suppressed, and the thermal history of the wafer 6 associated with pickup by the wafer placement plate 37 is reduced. Thereby, the quality of the film quality is improved. Note that the transfer chamber 12 is, for example, air or oxygen (O２ ), nitrogen (N) of 20 ppm or less ２ ). Also, since the back surface (rear surface) of the substrate 6 is exposed in the processing chamber 17, film formation is performed on both the front surface and the back surface (rear surface) facing the front surface of the substrate 6, so that warping of the substrate 6 can be prevented.

[0045] Next, a configuration example of the seal cap and its periphery will be described with reference to FIG. 3. FIG. 3 is a cross-sectional view for explaining a configuration example of the seal cap and its periphery, which is preferably used in one aspect of the present disclosure. In FIG. 3, the boat elevator 18 shown in FIG. 1 is described as the boat elevator 115, the seal cap 19 shown in FIG. 1 is described as the seal cap 219, and the rotation mechanism 21 shown in FIG. 1 is described as the rotation mechanism 265.

[0046] FIG. 3 depicts a cross-sectional perspective view between the boat elevator arm 115a of the boat elevator 115, the boat table 501 on which the first bottom plate 31a is placed, and the sub-boat placing table 541a on which the second bottom plate 41a is placed. A rotation mechanism 265 having a rotation shaft 225 is provided on the boat elevator arm 115a, and the rotation shaft 225 passes through the seal cap 219 and is connected to the boat table 501. The rotation shaft 225 is configured to coincide with the rotation center axis 451 shown in FIG. 2B. The rotation shaft 225 supports the boat table 501 rotatably. The disk-shaped boat table 501 fixes the rotation shaft 225 and supports the main boat 217a and the sub-boat 217b thereon. The boat table 501 is made of a metal material such as SUS, for example, and is formed in a disk shape. On the boat table 501, a sub-boat placing table 541a on which a disk-shaped second bottom plate 41a is fixed, and a ring-shaped first bottom plate 31a are placed around the placing table 541a. The boat table 501 has a plurality of openings 502 provided at positions corresponding to a plurality of pins 503 described later, and a plurality of pushers (hanging pins) 504 that are suspended and movable up and down within the plurality of openings 502. Therefore, the substrate transfer device 36 can be rephrased as a cylindrical coordinate system robot having a turning axis parallel to the rotation shaft 225 of the boat rotator 265.

[0047] Below the multiple pins 503, a drive device 100 is provided as a lift mechanism that can move the multiple pins 503 up and down. In other words, the substrate processing apparatus 1 is equipped with a lift mechanism (100) that can lift the substrate 6 held in the boat 15 without using a substrate transfer machine 36. The drive device 100 can be configured as, for example, an actuator. The multiple pins 503 and the drive device 100 may be combined to form the lift mechanism. Guides (joints) 505 are provided on the underside of the seal cap 219 for the multiple pins 503. The multiple pins 503 are provided penetrating the seal cap 219 while maintaining the airtightness of the seal cap 219 by a first bellows 510 provided between the boat stand 501 and the seal cap 219. The secondary boat stand 541a is configured to be pushed upward by the pusher 504, which is pushed up by the multiple pins 503, when the drive device 100 pushes up the multiple pins 503. In other words, one end of each of the multiple pins 503 outside the processing chamber 17 is in contact with or fixed to the boat elevator arm 115a. The other end of each of the multiple pins 503 inside the processing chamber 17 is configured to push upward the auxiliary boat platform 541a to which the second bottom plate 41a is fixed. As a result, the multiple movable support columns 400a-400d are configured to be lifted all at once (referred to as substrate pickup processing).

[0048] The space between the rotating device (rotating mechanism) 265 fixed to the elevator arm 115a and the seal cap 219 is sealed by a second bellows 507 that is provided so as to surround the rotating shaft 225.

[0049] Between the elevator arm 115a and the seal cap 219, a plurality of elastic support members 520 are provided to bias the seal cap 219 upward. The plurality of elastic support members 520 are provided around the second bellows 507. The plurality of elastic support members 520 are composed of, for example, a spring and a pin that applies an upward force by the spring.

[0050] Multiple verticality adjusters 101 capable of pushing up the pins constituting the elasticity adjusters 520 are provided on the lower side of the multiple elasticity adjusters 520. In addition, a rotation axis verticality sensor 102 for measuring the verticality of the rotation axis 225 is provided on the seal cap 219. The rotation axis verticality sensor 102 may also measure the load on the boat elevator arm 115a (bending moment of the arm).

[0051] Based on the measurement results of the rotation axis verticality sensor 102, if it is determined that the verticality of the rotation axis 225 is not appropriate (i.e., it is deviating from the vertical), the control unit 431 shown in Figure 4 controls a plurality of verticality adjusters 101 to adjust the restoring force of the spring by pushing up or down at least one pin of a plurality of elastic support members 520 using the corresponding verticality adjuster 101. This ensures that the verticality of the rotation axis 225 is properly adjusted.

[0052] Next, an example configuration of the controller 431 will be described with reference to Figure 4. Figure 4 is a diagram illustrating an example configuration of a controller preferably used in one aspect of this disclosure.

[0053] A controller 431, which is a control unit (controller, control means), is provided at a required location within the enclosure 2, for example, in the corner of the sub-enclosure 4 in Figure 1. As shown in Figure 4, the controller 431 is configured as a computer equipped with a CPU (Central Processing Unit) 432, RAM (Random Access Memory) 433, storage device 434, and I / O ports 435. The RAM 433, storage device 434, and I / O ports 435 are configured to exchange data with the CPU 432 via an internal bus 436. An input / output device 437, configured as, for example, a touch panel, is connected to the controller 431. An external storage device 438 can also be connected to the controller 431. The controller 431 is configured to also execute artificial intelligence (AI) programs.

[0054] The storage device 434 is composed of, for example, flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), etc. The storage device 434 contains, in a readable format, control programs that control the operation of the substrate processing device, and process recipes that describe the procedures and conditions in the substrate processing process described later. The process recipe functions as a program, combining the procedures in the substrate processing described later so that the controller 431 causes the substrate processing device to execute them and obtain a predetermined result. Hereinafter, process recipes and control programs will be collectively referred to simply as "programs." Similarly, process recipes will be simply referred to as "recipes." In this specification, the term "program" may include only recipes, only control programs, or both. The RAM 433 is configured as a memory area (work area) where programs and data read by the CPU 432 are temporarily held.

[0055] The I / O port 435 is connected to the opening / closing mechanism 11, the transfer machine 13, the processing furnace 16, the boat elevator 18, the rotating mechanism 21 (267), the actuator (drive device) 100, the verticality adjuster 101, the rotation axis verticality sensor 102, etc.

[0056] The CPU 432 is configured to read and execute control programs from the storage device 34, and to read recipes from the storage device 434 in response to input of operation commands from the input / output device 437. The CPU 432 is configured to control operations such as opening and closing the lid of the pod 3, transferring wafers 6 by the transfer machine 13, supplying and exhausting processing gas into the processing furnace 16, adjusting the flow rate of the processing gas, controlling the pressure and temperature of the processing chamber 17, raising and lowering the boat 15 (a combination of the main boat 217a and the sub-boat 217b) by the boat elevator 18, and rotating the boat 15 and adjusting its rotational speed by the rotating mechanism 21, in accordance with the contents of the read recipe. The CPU 432 is also configured to control operations such as pushing up the sub-boat platform 541a (sub-boat 217b) by the actuator (drive device) 100, and adjusting the restoring force of the springs by multiple verticality adjusters 101 based on the measurement results of the rotation axis verticality sensor 102.

[0057] The controller 431 can be configured by installing the above-mentioned program stored in the external storage device 438 onto a computer. The external storage device 438 includes, for example, magnetic disks such as HDDs, optical disks such as CDs, magneto-optical disks such as MOs, and semiconductor memory such as USB memory and SSDs. The storage device 434 and the external storage device 438 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. In this specification, the term recording media may include only the storage device 34, only the external storage device 438, or both. The program may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 438.

[0058] Next, the optical axes of the fiber sensors 51a and 51b, which serve as mapping sensors, will be explained using Figure 5. Figure 5 is a top view illustrating the optical axis of a mapping sensor suitably used in one embodiment of this disclosure.

[0059] As shown in Figure 5, the light transmitting and receiving sections 54a and 54b of the fiber sensors 51a and 51b are positioned at the tip ends of the sensor rods 50a and 50b. In other words, the optical windows 55a of the light transmitting and receiving section 54a and 55b of the light transmitting and receiving section 54b are provided on the fiber sensors 51a and 51b. Between the light transmitting and receiving sections 54a and 54b, an optical path (optical axis) 541 is positioned via the optical windows 55a and 55b. In other words, the mapping sensors 50a and 50b have a light transmitting section (one of 54a and 54b) that generates a light ray having the optical axis 541 in a plane perpendicular to the rotation axis 225 of the boat turner 265, and a light receiving section (the other of 54a and 54b) that receives the light ray.

[0060] In Figure 5, the sensor rods 50a and 50b, shown by dashed lines, are in the retracted position. At this time, the radius of rotation of the sensor rods 50a and 50b around the Y-axis is smaller than that of the Y-axis drive unit 362. On the other hand, the sensor rods 50a and 50b, shown by solid lines, are in the protruding position, and at this time, the radius of rotation of the sensor rods 50a and 50b around the Y-axis is larger than that of the Y-axis drive unit 362.

[0061] The sensor rods 50a and 50b are moved to their protruding positions on the wafer 6 side by the forward and backward drive units 365a and 365b. The positions of the optical windows 55a and 55b in the X direction, in other words, the position of the optical axis 541, are configured to be able to approach a position where the distance (d) from the rotation center of the boat 15 is shorter than the maximum distance (dm) to the edge of the wafer 6. In this example, it is assumed that the center of the rotation axis 225 and the center of the wafer 6 coincide perfectly. The wafer edge refers to all surfaces of the wafer except the main surface on which the electronic device is formed and its back surface, and may include the sides and bevels perpendicular to the main surface.

[0062] By setting the difference between the maximum distance (dm) and the distance (d) to a predetermined distance (a distance so small that detection is not a problem, for example, a distance of about 1 mm), the presence or absence of the wafer 6 can be detected. If the wafer 6 is present, the light rays on the optical axis 541 will be blocked by the wafer 6.

[0063] To detect the lateral displacement of the wafer 6, the boat 15 is rotated around the rotation axis 225 by the rotation mechanism 265, and the presence or absence of the wafer 6 is measured at, for example, three or more angles of the rotation axis 225. By combining the displacement vectors of the wafer 6 obtained from measurements in two or more directions, the direction and amount of lateral displacement of the wafer 6 in the horizontal direction can be calculated.

[0064] The operation of the mapping mechanism for wafers 6 on boat 15 (main boat 217a, sub-boat 217b) will be briefly explained. The optical axes 541 of fiber sensors 51a and 51b are set at distances slightly shorter and longer than the radial distance from the ideal center of the circular wafer 6, and the degree of light shielding (shading) of the optical axis 541 by the wafer 6 is measured. This makes it possible to detect the presence or absence of the wafer 6 and whether or not there is a displacement in one direction. Since the sensor rods 50a and 50b, which act as the mapping mechanism, can move up and down in the V direction, multiple wafers 6 placed in boat 15 can be detected simultaneously.

[0065] Next, the detection modes for lateral displacement detection will be explained using Figures 6, 7, and 8. Figure 6 is a flowchart of a first mode of lateral displacement detection preferably used in one embodiment of this disclosure. Figure 7 is a flowchart of a second mode of lateral displacement detection preferably used in one embodiment of this disclosure. Figure 8 is a flowchart of a third mode of lateral displacement detection preferably used in one embodiment of this disclosure.

[0066] As shown in Figure 6, in the first mode of lateral displacement detection, the following steps are performed.

[0067] (Step 01: S01) In Step 1, the forward and backward positions of the mapping sensors are adjusted. The Z-axis drive unit 361, Y-axis drive unit 362, X-axis drive unit 363, V-axis drive unit 364 and forward / backward drive units 356a and 356b are adjusted by the controller 431 so that the forward and backward positions of the sensor rods 50a and 50b, which serve as mapping sensors, are fixed at a predetermined distance (a distance small enough that detection is not a problem, for example, 1 mm) away from the edge of the wafer 6 where the center of the rotation axis 225 perfectly coincides, or at a position that is a predetermined distance inside the substrate 6.

[0068] (Step 02: S02) With the sensor rods 50a and 50b maintained in the forward and backward positions set in Step 1, the controller 431 adjusts the rotation mechanism 21 (267) to set the boat 15 to a first rotation axis angle (also called a first direction). Then, while maintaining this first rotation axis angle, the sensor rods 50a and 50b scan the wafer 6 of the boat 15 in the vertical direction to detect whether or not there is an obstruction of the optical axis in the first direction. At this time, the Z-axis drive unit 361 and the V-axis drive unit 364 are adjusted by the controller 431. The detection results in Step 2 are analyzed by the controller 431.

[0069] (Step 03: S03) With the sensor rods 50a and 50b maintained in the forward and backward positions set in Step 1, the controller 431 adjusts the rotation mechanism 21 to set the boat 15 to a second rotation axis angle (also called a second direction). Then, while maintaining this second rotation axis angle, the sensor rods 50a and 50b scan the wafer 6 of the boat 15 in the vertical direction to detect whether or not there is an obstruction of the optical axis in the second direction. At this time, the Z-axis drive unit 361 and the V-axis drive unit 364 are adjusted by the controller 431. The detection results in Step 3 are analyzed by the controller 431.

[0070] (Step 04: S04) With the sensor rods 50a and 50b maintained in the forward and backward positions set in Step 1, the controller 431 adjusts the rotation mechanism 21 to set the boat 15 to a third rotation axis angle (also called a third direction). Then, while maintaining this second rotation axis angle, the sensor rods 50a and 50b scan the wafer 6 of the boat 15 in the vertical direction to detect whether or not there is an obstruction of the optical axis in the third direction. At this time, the Z-axis drive unit 361 and the V-axis drive unit 364 are adjusted by the controller 431. The detection results in Step 4 are analyzed by the controller 431.

[0071] In other words, in the first mode, the control unit 431 controls the substrate transfer machine 36 to detect whether or not light rays are blocked at three or more different angles of the rotation axis 225, while the distance from the rotation axis 225 is fixed, so that the optical axis 541 is separated by a predetermined distance corresponding to the detection limit from the edge of the virtual substrate 6 whose center perfectly coincides with the rotation axis 225, thereby identifying the misaligned substrate 6. In this way, by scanning the wafer 6 on the boat 15 up and down at three or more rotation axis angles, it becomes possible to detect whether or not the wafer 6 is misaligned and the approximate direction of the misalignment. If only lateral misalignment is to be detected, it is preferable to scan in three directions: the front direction (the direction in which the substrate is loaded and unloaded from the boat 15 to the wafer 6 450), and 90 degrees to the left and 90 degrees to the right from the front direction.

[0072] When the mapping sensor is brought in from 90 degrees to the left or right (directly to the side), it is necessary to detect the presence or absence of the circuit board 6 that is placed on the slots (first support part 321) of the support pillars 300a, 300b, and 300c of the boat 15, distinguishing it from the support pillars 300a, 300b, and 300c.

[0073] Since the width of the groove in the slot (first support portion 321) (the vertical height of the first support portion 321) is constant, it is possible to determine whether or not it is wafer 6 by the distance from the top of the groove at which the optical axis (light ray) passes (whether it is the same as the width of the slot or shorter by the thickness of the wafer 6). Naturally, the resolution of the direction of displacement improves as the number of measurement directions increases. However, since the detection time increases, it is preferable to limit the number of measurement directions to an appropriate number, taking into account the resolution of the direction of displacement.

[0074] As shown in Figure 7, the following steps are performed in the second mode of lateral displacement detection.

[0075] (Step 11: S11) The forward and backward positions of the sensor rods 50a and 50b, which serve as mapping sensors, are kept fixed in the same position as in the first mode.

[0076] (Step 12: S12) For the wafer 6 that had misaligned in the first mode, the angle at which the blocking of light rays on the optical axis 541 begins and the angle at which it ends (called the critical angle) are measured while rotating the rotation axis 225. The critical angle is measured at the angles of the two rotation axes 225. This makes it possible to calculate the direction and amount of misalignment.

[0077] In other words, in the second mode, the control unit 431 rotates the rotation axis 225 while maintaining the optical axis 541 at a height corresponding to at least one of the substrates 6, measures the start and end angles of light ray obstruction by the mapping sensors (50a, 50b), and calculates the direction and magnitude of the displacement of the substrate 6 from these start and end angles. Note that if the surface of the wafer 6 is not perpendicular to the rotation axis 225 (i.e., if the surface of the wafer 6 is horizontal or slightly tilted), the height of the optical axis 541 will shift from the center of the wafer 6's thickness as the rotation axis 225 rotates, making accurate detection impossible. Therefore, the rotation of the rotation axis 225 is started from the angle at which light ray obstruction occurs in the optical axis 541, and when the light ray obstruction is resolved, the height of the optical axis 541 (i.e., the sensor rods 50a, 50b of the transfer machine 36) is slightly moved up and down by the V-axis drive unit 364 (or Z-axis drive unit 361). At this point, if there is a height at which light blocking occurs again, it is preferable to search again for the angle at which the light blocking is resolved at that height.

[0078] However, this operation cannot be used in situations where the optical axis 541 passes through the slot groove inside the boat 15. Therefore, the height of the wafer 6, which is known for the angle of the rotation axis 225, is used by fitting it to a trigonometric function.

[0079] As shown in Figure 8, the following steps are performed in the third mode of lateral displacement detection.

[0080] (Step 21: S21) The forward and backward positions of the sensor rods 50a and 50b, which serve as mapping sensors, are adjusted. The forward and backward positions of the sensor rods 50a and 50b can be changed to any position.

[0081] (Step 22: S22) With respect to the wafer 6 that was misaligned in the first mode, the sensor rods 50a and 50b are moved up and down in a meandering motion from the side (90 degrees to the left or 90 degrees to the right from the front direction) until the light beam is blocked. This allows the amount of misalignment in the approach direction to be measured directly. Even within the groove of the slot (first support part 321), it is sufficient to detect the position where the height at which the light beam is blocked changes by the thickness of the wafer 6.

[0082] (Step 23: S23) Measurements similar to those in step 21 are performed in at least two directions with different angles of rotation axis 225 (measurement in one direction is completed in step 21) to measure the amount of displacement. This makes it possible to determine the direction of the displacement and the magnitude of the displacement (amount of displacement). In other words, the controller 431 can calculate the horizontal displacement direction and amount of displacement by synthesizing the displacement vectors of the wafer 6 obtained by measurements in two or more directions. In other words, in the third mode, the control unit 431 moves the optical axis 541 up and down at a height corresponding to at least one of the substrates 6, and moves the optical axis 541 in at least one direction perpendicular to the rotation axis 225, detects the distance between the optical axis 541 and the rotation axis 225 at which light blocking occurs, and determines at least one of the direction of the displacement of the substrate 6 and the magnitude of the displacement in a predetermined direction. Furthermore, the transfer machine 36 is equipped with drive units (365a, 365b) that move the mapping sensors (50a, 50b) so that the distance between their optical axis 541 and rotation axis 225 changes. The control unit 431 is configured to detect the positional displacement of the substrate 6 in a direction perpendicular to the transfer direction 450 of the substrate 6 to the boat 15 by detecting the edge of the substrate 6 while changing the distance.

[0083] Next, the flow of the substrate processing method will be explained using Figure 9. Figure 9 is a diagram showing an example of a flow of a substrate processing method preferably used in one embodiment of this disclosure.

[0084] (2) Substrate Processing Process Using the substrate processing apparatus 1 described above, a method for processing a substrate as one step in the manufacturing method of a semiconductor device, for example, an example of a processing sequence for growing a film on the surface of a wafer 6 as a substrate, will be explained with reference to Figure 9. In the following explanation, the operation of each part constituting the substrate processing apparatus 1 is controlled by the controller 431.

[0085] In this specification, the term "wafer" may refer to the wafer itself or to a laminate of a wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of the wafer" may refer to the surface of the wafer itself or to the surface of a predetermined layer formed on the wafer. In this specification, when it is stated that "a predetermined layer is formed on the wafer," it may mean that the predetermined layer is directly formed on the surface of the wafer itself or that the predetermined layer is formed on top of a layer already formed on the wafer. In this specification, the term "substrate" is synonymous with the term "wafer." In this specification, numerical ranges such as "1 to 2000 Pa" mean that the lower and upper limits are included within that range. For example, "1 to 2000 Pa" means "1 Pa or more and 2000 Pa or less." The same applies to other numerical ranges. Also, when the supply flow rate includes 0 slm, 0 slm means the case in which the substance (gas) is not supplied. This also applies to the following explanations. In this specification, "processing temperature" refers to the temperature of the wafer 6 or the temperature inside the processing chamber 17, and "processing pressure" refers to the pressure inside the processing chamber 17. Furthermore, "processing time" refers to the duration for which the processing is continued. These definitions also apply in the following descriptions.

[0086] (Wafer charging: S31) Multiple wafers 6 are loaded onto the boat 15 (wafer charging). In other words, the substrates 6 are placed on the boat 15 in multiple stages by a substrate transfer machine 36 equipped with a wafer mounting plate 37, which is an end effector for gripping the substrates 6.

[0087] (Mapping: S32) When multiple wafers 6 are loaded into the boat 15, the sensor rods 50a and 50b of the transfer machine 36 are moved to a protruding position (towards the boat 15) by the forward and backward drive units 365a and 365b. Then, the sensor rods 50a and 50b are moved up and down at a constant speed by the Z-axis drive unit 361, and the fiber sensors 51a and 51b perform mapping of the wafers 6, detecting and mapping the wafers 6 in the boat 15 in order.

[0088] (Boat Loading: S33) Once mapping is complete, the lower end opening of the processing chamber 17 is opened. Then, as shown in Figure 1, the boat 15 supporting multiple wafers 6 is lifted by the boat elevator 18 and loaded into the processing chamber 17 (boat loading). In this state, the seal cap 19 seals the lower end of the manifold via the O-ring. In this way, the wafers 6 are loaded into the processing chamber 17.

[0089] (Heating: S34) After the boat loading is completed, the wafer 6 in the processing chamber 17 is heated by a heater to reach the desired processing temperature (first temperature). At this time, the amount of power supplied to the heater is feedback-controlled based on the temperature information detected by the temperature sensor so that the processing chamber 17 has the desired temperature distribution. The rotation of the wafer 6 by the rotation mechanism 265 is also started. The exhaust of the processing chamber 17, the heating of the wafer 6, and the rotation are all carried out continuously at least until the processing of the wafer 6 is completed.

[0090] [Film Formation Process (A1, A2): S35] (Step A1: Reaction Gas Supply Process) In Step A1, with the wafer 6 heated to a predetermined temperature, at least one of the first processing gas and the second processing gas is supplied to the wafer 6 to perform a film formation process in which a film is grown on the surface of the wafer 6.

[0091] When depositing a silicon germanium (SiGe) film, a second processing gas (a gas containing germanium (Ge)) is flowed through a second gas supply pipe. The flow rate of the second processing gas is adjusted and supplied into the processing chamber 17. In this state, the first processing gas is flowed through a first gas supply pipe. The flow rate of the first processing gas (a gas containing silicon (Si)) is adjusted and supplied into the processing chamber 17, and it is exhausted together with the second processing gas through the exhaust port. At this time, the first processing gas and the second processing gas are supplied to the wafer 6 from the side of the wafer 6. At this time, an inert gas may also be supplied into the processing chamber 17.

[0092] The following are examples of processing conditions in step A1.

[0093] Processing temperature (predetermined temperature): 500 to 650°C, preferably 550 to 600°C Processing pressure: 4 to 200 Pa, preferably 1 to 120 Pa First processing gas supply flow rate: 0.1 to 5 slm, preferably 0.2 to 3 slm Second processing gas supply flow rate: 0.1 to 5 slm, preferably 0.2 to 310 slm Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm, preferably 0.1 to 10 slm Gas supply time: 20 minutes to 60 hours, preferably 30 to 360 minutes By supplying the first processing gas and the second processing gas to the wafer 6 under the above processing conditions, an epitaxial film, such as an epitaxial SiGe film containing a predetermined element, can be formed on the surface of the wafer 6. Note that by supplying only the first processing gas as the raw material gas, a silicon (Si) film can be formed.

[0094] After step A1 is completed, the supply of the first and second processing gases into the processing chamber 17 is stopped.

[0095] (Step A2: Substrate Pickup Process) After step A1, the drive unit 100 moves the sub-boat 217b relatively upward to simultaneously lift multiple wafers 6 from the main boat 217a. After a certain period of time, the drive unit 100 moves the sub-boat 217b relatively downward to simultaneously place multiple wafers 6 on the main boat 217a. During step A2, the rotation of the boats 15 (217a, 217b) is stopped. During the substrate pickup process, information such as the values ​​of the rotation axis verticality sensor 102 and other sensors, as well as processing conditions (such as the speed of the substrate pickup operation), is acquired and stored in the storage device 434.

[0096] [Performance a predetermined number of times] The cycle of performing steps A1 and A2 alternately described above is performed a predetermined number of times (n times, where n is an integer of 1 or more).

[0097] (Cooling down: S36) After the film deposition process is completed, the wafer 6 in the processing chamber 17 is cooled down to a temperature such as room temperature so that it reaches the desired processing temperature (second temperature).

[0098] (Boat unloading: S37) Subsequently, the seal cap 219 is lowered by the boat elevator 18, and the lower end of the manifold is opened. Then, the processed wafers 6, supported by the boat 15, are unloaded from the lower end of the manifold to the outside of the processing chamber 17 (boat unloading).

[0099] (Misalignment detection process: S38) The first, second, and third modes of lateral misalignment detection described in Figures 6, 7, and 8 are implemented. In other words, the control unit 431 controls the boat rotator 265 that rotates the boat 15 and the mapping sensors (50a, 50b) having optical axes 541 in a plane perpendicular to the rotation axis 225 of the boat rotator 265 to attempt to detect the edge of the substrate held on the boat 15 from at least two directions, including a direction different from the direction in which the substrate 6 is transferred to the boat 15. Furthermore, the control unit 431 is configured such that, in at least one of the detection directions, the mapping sensors (50a, 50b) can detect light that has passed through the slots 321 of the support columns (300a-300c) of the boat 15, which are located between the light-emitting and light-receiving sections (transmitting and receiving sections 54a, 54b) of the mapping sensors (50a, 50b). Furthermore, after the substrate 6 is lifted by the lift mechanism (100), a misalignment detection process S38 is performed to detect any misalignment of the substrate 6.

[0100] (Misalignment tendency learning process: S39) In the misalignment tendency learning process S9, the controller 431 causes the AI ​​to learn the relationship between various sensor values ​​and other information during the pickup process and the misalignment of the wafer 6. If the previous substrate processing process was performed and the lateral misalignment reduction process S40, which will be described next, was performed, the controller 431 may also learn the relationship between the contents of that process and the reduction of the misalignment of the substrate 6. In other words, the control unit 431 is configured to execute an AI that learns the relationship between information regarding the situation when the substrate 6 is lifted by the lift mechanism (100) and the detected positional misalignment of the substrate 6.

[0101] (Lateral displacement reduction process: S40) The lateral displacement reduction process determines (or does not correct) the displacement of the substrate 6 currently on the boat 15 in order to reduce the likelihood of transport errors, and then implements it. Here, one of the following methods will be implemented.

[0102] Method 1: The controller 431 can determine that if the displacement of the wafer 6 is small enough that the risk of transport errors is negligible, then the displacement of the wafer 6 does not need to be corrected.

[0103] Second method: If many wafers 6 are shifted in the same direction (representative direction), the controller 431 uniformly rotates all substrates 6 by a predetermined angle so that the representative direction becomes the substrate loading / unloading direction 450. If the amount of rotation that can be achieved in a single substrate pickup operation is small, the controller 431 repeats the substrate pickup operation multiple times.

[0104] In other words, before the transfer machine 36 removes the substrate 6 from the boat 15, the control unit 431 controls the drive unit 100 and the rotation mechanism 265, which act as a lift mechanism, to rotate the multiple substrates 6 uniformly relative to the boat 15 by an angle determined based on a predetermined trend, when the misalignment of the multiple substrates 6 currently held in the boat 15 shows a predetermined trend.

[0105] Third method: The controller 431 performs the substrate pickup operation with the boat 15 slightly tilted in the opposite direction to the direction in which the wafer 6 has shifted. This allows the substrate 6 to be shifted (moved) in the direction of the boat 15's tilt. The tilt of the boat 15 can be controlled by the force with which the seal cap 219 is pressed against the furnace opening and by the verticality adjuster 101.

[0106] Fourth method: The controller 431 causes the AI ​​to derive one or more combinations of processing conditions and board pickup operations that can correct the current misalignment of each board 6. Then, the controller 431 sets to the derived state and performs the board pickup operation to correct the misalignment of the boards 6.

[0107] Fifth method: The controller 431 corrects the misalignment of each misaligned wafer 6 by rotating it so that the direction of misalignment is directly opposite to the transfer machine 36, and then pressing it down with the wafer mounting plate 37.

[0108] Sixth method: The controller 431 does not correct the misalignment of the wafer 6, but controls the wafer mounting plate 37 to correct the insertion position (front-to-back and left-to-right directions) of the wafer mounting plate 37 to match the misalignment of the wafer 6 during substrate removal (wafer discharge described later: S42). The correction value is adjusted to a range where the wafer mounting plate 37 and wafer 6 do not come into contact with the support columns 300a-300c, and then passed on to the subsequent wafer discharge process (S42).

[0109] In other words, before the transfer machine 36 removes the substrate 6 from the boat 15, the control unit 431 corrects the position of the wafer mounting plate 37 when the transfer machine 36 applies it to the substrate 6 (for example, when scooping it up) based on the detected positional deviation.

[0110] Method 7: The controller 431 does not correct the misalignment of the wafer 6, but determines the risk of a transport error based on the amount and direction of the misalignment. If there is a wafer 6 whose transport error risk exceeds a predetermined value, the controller 431 is configured to issue an alarm and interrupt the wafer discharge process to prompt manual misalignment correction when at least the wafers 6 below the wafer 6 in question have been discharged during the wafer discharge process (S42).

[0111] (Misalignment correction judgment: S41) If the misalignment of the wafer 6 is corrected in the lateral misalignment reduction process S40 (Yes), the process returns to the misalignment detection process S38. If it is not corrected (No), the process proceeds to the wafer discharge process S42.

[0112] (Wafer Discharge: S42) After boat unloading, the processed wafers 6 are transported outside the processing chamber 17 and then removed from the boat 15 (wafer discharge). In the wafer discharge process S42, if contact with the boat 15 (detected by torque abnormality or vibration sensor) or detachment of the wafer 6 is detected by the sensor during transport, the results can also be taught to the AI. This makes it less likely for a transport error method (the method implemented in the lateral displacement reduction process S40) to be selected, or the content of the method is improved.

[0113] According to this embodiment, one or more of the following effects can be obtained.

[0114] (1) The substrate processing apparatus 1 comprises a boat rotator 265 that rotates a boat 15 that holds substrates 6 in multiple stages, a substrate transfer machine 36 equipped with an end effector (37) that grips the substrates 6, sensor rods 50a and 50b as mapping sensors having an optical axis 541 in a plane perpendicular to the rotation axis 225 of the boat rotator 265 and configured to optically detect the edges of the substrates 6 held on the boat 15, and a control unit 431 configured to control the substrate transfer machine 36 and the boat rotator 265 so that the edges of the substrates 6 held on the boat 15 are detected by the mapping sensors from at least two directions, including a direction different from the transfer direction 450 of the substrates 6 to the boat 15. Furthermore, the substrate processing method includes the steps of: placing substrates 6 on a boat 15 in multiple stages using a substrate transfer machine 36 equipped with an end effector (37) for gripping substrates 6 (S31); and controlling a boat rotator 265 for rotating the boat 15 and mapping sensors (50a, 50b) having optical axes 541 in a plane perpendicular to the rotation axis 225 of the boat rotator 265 to attempt to detect the edges of the substrates 6 held on the boat 15 from at least two directions, including a direction different from the transfer direction 450 of the substrates 6 to the boat 15 (S38). This makes it possible to detect the amount of lateral displacement of the substrates 6 using existing hardware, such as sensor rods 50a and 50b as mapping sensors.

[0115] (2) It is possible to detect whether there is a misalignment between the pillars (15a-15c:300a-300c) of the boat 15 and the substrate 6 that would cause them to come into contact.

[0116] (3) The amount of lateral displacement of the substrate 6 is detected and corrected, making it possible to prevent transport errors caused by lateral displacement.

[0117] (4) The method can also be easily applied to a transfer machine 13 having a multilayer wafer mounting plate 14, as it utilizes the sensor rods 50a and 50b. The optical axes 541 of the sensor rods 50a and 50b detect when the incident angle is around 90 degrees (almost total internal reflection). Therefore, it can also be applied to a transparent substrate 6.

[0118] (5) Since the mapping sensors (50a, 50b) do not enter the boat 15 (within the substrate arrangement area), there is no risk of the mapping sensors coming into contact with the substrate 6 that is improperly mounted.

[0119] (6) It is possible to understand the trend of positional displacement associated with the operation of the substrate pickup process and to estimate the cause.

[0120] This disclosure is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are described in detail for the purpose of making this disclosure easy to understand, and are not necessarily limited to those having all the configurations described.

[0121] Furthermore, while the above-mentioned configurations, functions, and control units such as controllers have been explained primarily through examples of creating programs to implement some or all of them, it goes without saying that some or all of them may also be implemented in hardware, for example, by designing them as integrated circuits. In other words, all or part of the functions of the processing unit may be implemented by integrated circuits such as ASICs (Application Specific Integrated Circuits) and FPGAs (Field Programmable Gate Arrays) instead of programs.

[0122] The above-described embodiments illustrate an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at once. This disclosure is not limited to the above-described embodiments and can be suitably applied, for example, to forming a film using a single-wafer substrate processing apparatus that processes several substrates at once. Furthermore, the above-described embodiments illustrate an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the above-described embodiments and can be suitably applied to forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0123] 1: Substrate processing equipment 12, 36: Substrate transfer machine 14, 37: Wafer mounting plate (end effector) 15: Boat 21: Boat rotating machine (rotating mechanism) 50a, 50b: Sensor rod (mapping sensor)

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