Substrate cassette handling device, substrate processing device, substrate processing method, manufacturing method of semiconductor device and program

Abstract

To provide a technique capable of improving accuracy in detecting that a direction of a substrate is correct.SOLUTION: A substrate cassette handling device comprises: a stage on which a cassette in which a plurality of substrates each including an azimuth identification section is stored is loaded; a reflector provided in one end of a predetermined optical path which is set in such a manner that light can pass without irradiating each of the plurality of substrates when the azimuth identification section of the substrate is in a predetermined direction; a robot including a reflection type photosensor, which irradiates the optical path with light and is configured to sense reflection light from the reflector, and transferring the cassette between the stage and a shelf which is provided inside of the device; and a control section configured to control the robot so as to move the reflection type photosensor to a position corresponding to the optical path when confirming that the azimuth identification sections of the plurality of substrates on the stage match the predetermined direction.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] In a cassette transfer unit on which a wafer cassette is placed, orientation flat alignment is performed to align the orientation flat (hereinafter referred to as "orientation flat"), which indicates the crystal orientation of the wafer. Some wafer placement tables are equipped with orientation flat confirmation sensors that detect whether the orientation flats of multiple wafers are aligned before the orientation flat alignment work (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-270675 A Summary of the Invention [Problem to be solved by the invention]

[0004] In some cases, a cassette transfer unit is required to handle substrates of different diameters and materials. However, because the dimensions and light transmittance of the orientation flat and other features differ depending on the diameter and material of the substrate, the detection accuracy of the sensor that checks whether the substrate is oriented correctly can decrease.

[0005] The present disclosure provides a technique that can improve the accuracy of detecting whether a substrate is correctly oriented. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a stage on which a cassette containing a plurality of substrates each having an orientation identifying portion is placed; a reflector provided at one end of a predetermined optical path that is set so that light can pass through the substrate without hitting the substrate when the orientation specifying portion of each of the plurality of substrates is oriented in a predetermined direction; a robot having a reflective optical sensor configured to irradiate light along the optical path and detect reflected light from the reflector, the robot transporting the cassette between the stage and a shelf provided within the apparatus; a control unit configured to be able to control the robot so that the reflective optical sensor moves to a position corresponding to the optical path when confirming that the orientation identification units of the plurality of substrates on the stage match a predetermined orientation; and A technique is provided that includes: Effect of the Invention

[0007] According to the present disclosure, it is possible to improve the accuracy of detecting whether the orientation of a substrate is correct. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram for explaining a substrate processing apparatus according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of a cassette stage and a cassette transfer device in the embodiment. [Diagram 3] FIG. 3 is a diagram for explaining confirmation of the orientation flat by a reflective optical sensor. [Figure 4] FIG. 4 is a diagram illustrating a recurrent reflection sensor. [Diagram 5] FIG. 5 is a perspective view of the cassette receiving unit according to the embodiment. [Figure 6] FIG. 6 is a perspective view of the comb sensor and the wafer attitude aligning device provided on the cassette stage. [Figure 7A] FIG. 7A is a diagram showing a process flow illustrating a substrate processing method according to an embodiment. [Figure 7B] FIG. 7B is a diagram showing a process flow illustrating the substrate processing method according to the embodiment. [Figure 8]FIG. 8 is a diagram for explaining wafer mapping by a reflective optical sensor. [Figure 9] FIG. 9 is a flowchart showing a detailed process for checking the orientation flat in the modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, one embodiment of the present disclosure will be described with reference to the drawings. Note that all drawings used in the following description are schematic, and the dimensional relationship of each element, the ratio of each element, etc. shown in the drawings do not necessarily match the actual ones. In addition, the dimensional relationship of each element, the ratio of each element, etc. do not necessarily match between multiple drawings. In addition, between multiple drawings, substantially the same elements are given the same reference numerals, and each element is explained in the drawing in which it first appears, and the explanation is omitted in the subsequent drawings unless particularly necessary. Unless otherwise specified in the specification, each element is not limited to one, and may be present in multiple numbers.

[0010] (1) Substrate processing equipment In this embodiment, the substrate processing apparatus (hereinafter also simply referred to as a processing apparatus) is configured as a semiconductor manufacturing apparatus that performs processing steps in a manufacturing method for semiconductor devices, as an example.

[0011] As shown in Fig. 1, the processing apparatus 10 according to the embodiment includes a housing 11, and a cassette transfer unit 12 is provided on the front side (X1 side) of the housing 11. The X1-X2 direction is the front-rear direction of the processing apparatus 10, the Y2-Y1 direction is the left-right direction, and the Z1-Z2 direction is the up-down direction. The cassette transfer unit 12 includes a cassette stage device (also called a cassette loader) 13 capable of mounting two open cassettes (hereinafter simply called cassettes) 2 as substrate containers that are carriers of wafers 1 as substrates, and two sets of wafer attitude alignment devices 14 are provided below the cassette stage device 13. In other words, the cassette stage device 13 includes a plurality of stages, and each stage is configured to be able to transfer the cassette 2 to and from the outside of the apparatus.

[0012] The cassette 2 transported by an external transport device (not shown) is placed on a mounting table 44 (described later) of the cassette stage device 13 in a vertical posture (a state in which the wafers 1 stored in the cassette 2 are vertical, and the wafers 1 are arranged horizontally and stored) as a first posture. The wafer posture alignment device 14 includes an orientation alignment mechanism that aligns the posture of the wafers 1 so that the notches and orientation flats serving as orientation specifying parts of the wafers 1 stored in the cassette 2 are the same when the cassette 2 is in the vertical posture. The cassette stage device 13 includes a cassette inversion mechanism that rotates the mounting table 44 by 90 degrees to bring the cassette 2 into a horizontal posture (a state in which the wafers 1 are arranged vertically and stored) as a second posture. Inside the housing 11, a cassette shelf 15 is provided facing the cassette transfer unit 12, and a spare cassette shelf 16 is provided above the cassette transfer unit 12.

[0013] A cassette transport robot 17 is provided between the cassette delivery unit 12 and the cassette shelf 15. The cassette transport robot 17 is equipped with a robot arm 18 having a hand 173 that can advance and retreat in the front-rear direction (X1-X2 direction), and the robot arm 18 itself is configured to be able to move laterally and ascend and descend. The ascending and descending and lateral movements of the robot arm 18 and the forward and backward (front-rear) movements of the hand 173 scoop up the cassette 2 that is in a horizontal position on the cassette stage device 13 from below, transport it to the cassette shelf 15 or the spare cassette shelf 16, and transfer it. The cassette shelf 15 and the spare cassette shelf 16 can also be considered as buffer shelves for multiple cassettes 2. Since the cassette stage device 13 is equipped with a cassette inversion mechanism, both orientation alignment by the wafer posture alignment device 14 and cassette transport by the cassette transport robot 17 are possible.

[0014] A wafer transfer device (transfer machine) 19 capable of transferring the wafers 1 in the cassette 2 all at once or one by one to a substrate support (hereinafter referred to as a boat) 25 is provided behind the cassette shelf 15 (X2 side) and can rotate and rise and fall. The wafer transfer device 19 has a wafer holding section 20 which can move forward and backward, and a plurality of wafer holding plates 21 are attached horizontally to the wafer holding section 20. A boat elevator 22 is provided behind the wafer transfer device 19 (X2 side), and a seal cap 24 which rotatably holds a boat 25 is horizontally installed on an arm 23 of the boat elevator 22.

[0015] The processing apparatus 10 has a transfer chamber 50 and a cassette holding chamber 60. In the transfer chamber 50, a wafer transfer device 19, a wafer holding section 20, a wafer holding plate 21, a boat elevator 22, etc. are installed. In the cassette holding chamber 60, a cassette shelf 15, a spare cassette shelf 16, a cassette transport robot 17, etc. are installed. A wall section 70 is provided between the transfer chamber 50 and the cassette holding chamber 60. The wafer transfer device (transfer machine) 19 transfers the wafer 1 from the cassette 2 in the cassette holding chamber 60 to the boat 25.

[0016] The processing apparatus 10 is equipped with a reaction tube (processing tube) 31 made of a highly heat-resistant material such as quartz glass and formed into a cylindrical shape with one end open and the other end closed, and the reaction tube 31 is vertically arranged with its center line vertical and fixedly supported. The cylindrical hollow part of the reaction tube 31 forms a processing chamber 32 in which multiple wafers 1 are accommodated, and the lower end opening of the reaction tube 31 forms a furnace port 33 for loading and unloading the wafers 1. The furnace port 33 opens into a transfer chamber 50, and the processing chamber 32 and the transfer chamber 50 are connected to each other.

[0017] A seal cap 24 for closing the furnace throat 33 is adapted to be in contact with the lower end surface of the reaction tube 31 from below in the vertical direction. The seal cap 24 is formed in a disk shape, and is adapted to be raised and lowered in the vertical direction by a boat elevator 22 provided outside the reaction tube 31. In addition, a furnace throat shutter 28 for sealing the furnace throat 33 when the seal cap 24 is moved to the lower end position may be provided.

[0018] A boat 25 for holding the wafers 1 is supported vertically on the seal cap 24. The boat 25 has a pair of upper and lower end plates 26, 27, and a plurality of holding members (pillars) (three in this embodiment) vertically arranged between the end plates 26, 27, and each holding member has a number of holding grooves that are equally spaced in the longitudinal direction and recessed so that they open opposite each other. The outer peripheral edges of the wafers 1 are inserted between the multiple holding grooves of each holding member, so that the multiple wafers 1 are held in the boat 25 horizontally and aligned with their centers aligned with each other.

[0019] 2, the cassette transport robot 17 includes a CZ drive shaft 171 as a third axis that moves the robot arm 18 as a first axis in the up and down direction (Z1-Z2 direction), and a CS drive shaft 172 as a second axis that moves the CZ drive shaft 171 in the left and right direction (Y2-Y1 direction). In other words, the robot arm 18 is a movable part that can move laterally and vertically. This allows access to a cassette at any position.

[0020] 2 and 3, a reflective optical sensor 101 is provided at the base, for example, at the lower end, of the robot arm 18. In other words, the reflective optical sensor 101 is provided on a movable part of the cassette transport robot 17. The reflective optical sensor 101 cannot be driven by the robot arm 18. Therefore, the reflective optical sensor 101 can also move laterally and vertically.

[0021] As shown in FIG. 2 and FIG. 3, the cassette stage device 13 is provided with two (a pair) reflectors 105 for each cassette 2 on the opposite side of the reflective optical sensor 101 with the cassette 2 in between. In other words, the cassette stage device 13 is provided with four (two pairs) reflectors 105. The bottom opening of the cassette 2 placed on the cassette stage device 13 is located at a position where the reflective optical sensor 101 and the reflector 105 face each other. As shown in FIG. 3, the reflective optical sensor 101 is provided at a predetermined distance from the cassette 2. Note that the wafer 1 stored in the cassette 2 placed on the cassette stage device 13 is in a vertical state. Also, as shown in FIG. 2, the cassette stage device 13 is provided with reflectors 106 extending in the X1-X2 direction beside each wafer alignment hole 53 described later.

[0022] Although an example in which the reflector 105 is provided on the cassette stage device 13 has been described, the present invention is not limited to this. When the cassette 2 is not inserted into the cassette stage device 13 from above but from the front of the device and the reflector 105 becomes an obstacle, for example, the reflector 105 may be provided on a movable shutter of a cassette insertion port on the front panel of the device.

[0023] The reflective optical sensor 101 and the reflector 105 will be described with reference to Fig. 4. The reflective optical sensor 101 includes a light-emitting unit 101a that emits outgoing light LO toward the wafer 1 stored in the cassette 2, and a light-receiving unit 101b that receives reflected light LR from the outgoing light LO reflected by the reflector 105. In the reflective optical sensor 101, for example, the light-emitting unit 101a and the light-receiving unit 101b are disposed adjacent to each other and integrated, forming a so-called reflective photoelectric sensor.

[0024] The reflective optical sensor 101 includes a polarizing filter 101c arranged on the light-emitting unit 101a side and a polarizing filter 101d arranged on the light-receiving unit 101b side. The polarizing filters 101c and 101d have mutually different polarization directions, i.e., perpendicular to each other in this embodiment.

[0025] The emitted light LO passes through the polarizing filter 101c and becomes linearly polarized light (e.g., a wave in the Y1-Y2 direction) vibrating in one direction (first direction), and then turns into a beam of parallel light and travels toward the reflector 105. The emitted light LO is then reflected back by the reflector 105 and travels toward the light receiving unit 101b as reflected light LR. The reflected light L2 becomes linearly polarized light vibrating in one direction (second direction) perpendicular to the emitted light LO (e.g., a wave in the Z1-Z2 direction), and can pass through the polarizing filter 101d. In other words, the polarizing filter 101d is a polarizing filter with an absorption axis in the first direction. The reflective optical sensor 101 can accurately determine (detect) whether the orientation flat of the wafer 1 is aligned based on the presence or absence of the reflected light LR.

[0026] The reflector 105 is configured to reflect light having a polarization direction different from that of the incident light (outgoing light LO) incident on the reflector 105 back to the light receiving unit 242 as reflected light LR. For example, the reflecting surface 105a of the reflector 105 is configured with a large number of regularly arranged corner cubes 105b. A "corner cube" is a minute depression having a shape in which three planes are combined so as to be perpendicular to each other. This allows the reflector 105 to perform back reflection. Note that in FIG. 4, one corner cube 105b is enlarged and depicted as a representative example. The reflector 105 may also include a transparent particle member. The reflector 105 is not limited to being configured with corner cubes 105b, and may be any reflector that rotates the polarization direction of the incident light more than when it is reflected by the wafer 1.

[0027] The reflector 105 is provided at one end of a predetermined optical path LP that is set so that the emitted light L1 from the reflective optical sensor 101 can pass through without hitting the wafer 1 when the orientation flats of the wafers 1 are aligned in a predetermined direction (aligned in a predetermined position). The optical paths LP are perpendicular to the surface of the wafer 1, and a plurality of optical paths LP are set for one cassette 2 on the cassette stage device 13. In the embodiment, two optical paths LP are set corresponding to the vicinity of both ends of the orientation flats of the wafers 1 aligned in the predetermined direction in the cassette 2, but three or more optical paths LP may be set. The controller 121 as a control unit moves the reflective optical sensor 101 to a plurality of positions corresponding to the plurality of optical paths LP in sequence to check whether the orientation flats of the wafers 1 are aligned in the predetermined direction. In other words, the controller 121 moves the reflective optical sensor 101 to the other end of the optical path set for the cassette being checked, so that the reflective optical sensor 101 is used in common for a plurality of cassettes.

[0028] When the orientation flats of all the wafers 1 are aligned, in the two optical paths LP, the emitted light L1 from the light emitter 101a hits the reflector 105, and the reflected light L2 returns to the light receiver 101b. On the other hand, when even one of the orientation flats of the wafers 1 is not aligned (when the orientation flat is not horizontal), in one of the optical paths LP, the emitted light L1 from the light emitter 101a is blocked by the wafer 1 and does not reach the reflector 105, and the reflected light L2 does not return to the light receiver 101b. The emitted light L1 is reflected by the wafer 1, and the reflected light returns to the light receiver 101b side, but it cannot pass through the polarizing filter 101d and is not detected by the light receiver 101b. The entry of a light-transmitting wafer 1 such as silicon carbide (SiC) into the optical path LP is detected as a decrease in the light receiving level at the light receiver 101b. In the reflective optical sensor 101, the attenuation of the light receiving level due to the wafer 1 having light transmitting properties is twice as much as that of the transmissive type, and therefore the detection accuracy is excellent.

[0029] Although the case where the wafer 1 has an orientation flat has been described, it is also possible to check whether the notches are aligned when the wafer 1 has a notch formed by cutting a part of the circumference of the wafer into a V shape. In this case, one optical path LP is set for each cassette 2 on the cassette stage device 13. The cassette stage device 13 is provided with one reflector 105 for each cassette 2, on the opposite side of the cassette 2 to the reflective optical sensor 101. In other words, the cassette stage device 13 is provided with two reflectors 105.

[0030] Controller 121 controls cassette transport robot 17 to move reflective optical sensor 101 to a detection position for the orientation flat or notch corresponding to the size, material, etc. of the wafer. Before the movement, reflective optical sensor 101 is in the position (home position) shown in Fig. 2. After checking the orientation flat alignment, reflective optical sensor 101 returns to the home position. Meanwhile, reflector 105 does not need to be moved, as it is formed to a size that can reflect the outgoing light on optical path LP for all types of wafers to be handled.

[0031] As shown in Fig. 3, the output (current value) of the reflective optical sensor 101 is input to the controller 121 via the amplifier unit 102. The amplifier unit 102 performs threshold judgment. The threshold is set, for example, to an intermediate light receiving level when the orientation flats of all silicon carbide (SiC) wafers are aligned and a light receiving level when only one wafer (e.g., SiC) with the highest light transmittance among the wafers to be handled is not aligned. Here, when only one wafer is not aligned, this refers to when one wafer blocks one or both of the light projection and reception paths of the reflective optical sensor 101.

[0032] In addition to the above-mentioned example of making an absolute value judgment using a fixed optical path, while checking the orientation flat, reflective optical sensor 101 may be moved in the Y2-Y1 direction along the orientation flat, or in the Z1-Z2 direction across the edge, to make a judgment based on the change in intensity (relative value judgment). Note that because light is scattered at the edge of the wafer, large changes in the light reception level can be observed even with a wafer whose transmittance is close to 100%.

[0033] The controller 121 will be described with reference to Fig. 3. The controller 121 is configured as a computer including a CPU (Central Processing Unit) 121a, a RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to communicate with the CPU 121a via an internal bus. An input / output device 122 configured as, for example, a touch panel, and an external storage device 123 are connected to the controller 121.

[0034] The storage device 121c is composed of, for example, a flash memory, a HDD (Hard Disk Drive), etc. A control program for controlling the operation of the substrate processing apparatus, a process recipe in which procedures and conditions of substrate processing described later are described, etc. are readably stored in the storage device 121c. The recipe is a combination of procedures in a substrate processing process described later that are executed by the controller 121 to obtain a predetermined result, and is a high-level language compared to the control program. The control program and the recipe are collectively called a program. The storage device 121c also sequentially stores log information that records the operation and state of the apparatus. The RAM 121b is configured as a memory area (work area) in which programs, data, etc. read by the CPU 121a are temporarily held.

[0035] The I / O port 121d is connected to the cassette receiving unit 12, the cassette stage device 13, the wafer attitude aligning device 14, the cassette transport robot 17, the wafer transfer device 19, the rotation mechanism 40, the boat elevator 22, the amplifier unit 102, and the like.

[0036] The CPU 121a is configured to read and execute a control program from the storage device 121c, and also to read a substrate recipe from the storage device 121c in response to an input of an operation command from the input / output device 122. The CPU 121a is configured to control the posture alignment operation of the cassette receiving unit 12, the rotation operation of the cassette stage device 13, the wafer posture alignment device 14, operation control of the robot arm 18 of the cassette transport robot 17, rotation and elevation control of the wafer transfer device 19, elevation operation of the boat elevator 22, etc., in accordance with the contents of the read recipe.

[0037] The controller 121 can be configured by installing the above-mentioned programs and recipes stored in an external storage device (for example, a magnetic disk such as a hard disk, or a semiconductor memory such as a USB memory) 123 into a computer. The storage device 121c and the external storage device 123 are configured as tangible computer-readable recording media.

[0038] Hereinafter, these will be collectively referred to simply as a recording medium. When the term recording medium is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0039] The cassette receiving unit 12 will be described with reference to FIG.

[0040] A frame 43 is formed by fixing a front plate 41 on the X1 direction side and a rear plate (not shown) on the X2 direction side to the lower part of a left side plate 38 on the Y2 direction side and a right side plate 39 on the Y1 direction side, and the lower part of the frame 43 is shaped like a square tube.

[0041] Two hinge members 35 are fixed, one above the other, to the outer surface of the right side plate 39 at the end on the front plate 41 side. Two hinge members 36 are fixed to the front side (X1 direction side) of the housing 11 shown in Fig. 1 and are connected to the corresponding hinge members 35. The cassette stage device 13 is rotatably supported with respect to the housing 11 by the hinge member 35 which is rotatable around an axis in the Z1-Z2 direction.

[0042] The rotating shaft 49 supports the mounting table 44 on the left side plate 38 and the right side plate 39 so as to be rotatable around the CY axis. The mounting table 44 includes a pair of rotating plates 45a, 45b, an internal receiving stage 46, an external receiving stage 47, and a lower plate 48. The rotating plates 45a, 45b are fixed to the rotating shaft 49 on the CY axis, and are rigidly connected between them by the lower plate 48. The mounting table 44 is rotatable around the rotating shaft 49. The internal receiving stage 46 is fixed to the rotating plates 45a, 45b and / or the lower plate 48. The external receiving stage 47 is attached to the horizontal rotating plates 45a, 45b via a plurality of guides 51 that allow movement in only one direction so that the cassette can move up and down in a vertical position. The air cylinder 52 is provided between the internal receiving stage 46 and the external receiving stage 47, and drives the external receiving stage 47 up and down. In other words, the cassette stage device 13 is equipped with a vertical movement mechanism. The external transfer stage 47 is also movable in the front-rear direction (X1-X2 direction). Two cassettes 2 can be placed on the internal transfer stage 46 and the external transfer stage 47. In other words, each of the internal transfer stage 46 and the external transfer stage 47 is composed of two stages.

[0043] Two wafer alignment holes 53 are provided at a predetermined interval in the external delivery stage 47. Below the wafer alignment holes 53, the wafer attitude adjustment device 14 is provided on the lower plate 48.

[0044] A drive unit 65 that rotates the rotation shaft 49 is attached to the outer surface of the right side plate 39. The drive unit 65 includes, for example, an AC servo motor, a worm gear box, a position sensor, etc., and is configured to be able to rotate the cassette 2 on the mounting table 44 by 90 degrees between a horizontal position and a vertical position.

[0045] The vertical movement mechanism of the cassette stage device 13 enables the external transfer stage 47 to be moved vertically between an upper position where the cassette 2 in a vertical position (upright state) can be rotated by the cassette inversion mechanism and a lower position where it can be aligned by the orientation alignment mechanism (wafer orientation alignment device 14).

[0046] When the external receiving stage 47 is in the upper position, it moves back and forth to press (dock) the inserted cassette 2 against the upright internal receiving stage 46, or to move (undock) the cassette 2 away from the internal receiving stage 46. In addition, when the external receiving stage 47 is in the upper position, an optical path LP is disposed in the space formed between the cassette 2 and the wafer attitude alignment device 14, making it possible to check the orientation flat.

[0047] An example of the wafer position aligning device 14 will be described with reference to FIG.

[0048] The wafer posture alignment device 14 includes a support table 141, a pair of rollers 142a, 142b rotatably suspended horizontally across the support table 141, a rotation drive device 143, and a stopper 144 provided adjacent to the roller 142b. The pair of rollers 142a, 142b extend in the alignment direction (X1-X2 direction) of the group of wafers 1 stored in the cassette 2. The rotation drive device 143 synchronously rotates the rollers 142a, 142b in the same direction. The wafer posture alignment device 14 is configured to be able to rise and fall relative to the cassette 2 placed on the placement table 44. During the alignment operation, the wafer position alignment device 14 is raised so that the multiple wafers 1 inside the cassette 2 placed on the cassette stage device 13 come into contact with the rollers 142a, 142b, and the wafers 1 are rotated in the same direction by both rollers 142a, 142b, thereby aligning the orientation flats among the multiple wafers 1 to a fixed position. In other words, the orientation flat alignment is performed mechanically by rotating the rollers 142a, 142b so that the wafers 1 rotate at least one time, and when the orientation flats match, the rotation is restricted by the stopper 144, which acts as a stopper, and the rollers 142a, 142b rotate freely. The orientation flat alignment can take several minutes, including the vertical movement of the external transfer stage 47. Notch alignment is also achieved by a similar mechanism.

[0049] In addition, the wafer posture alignment device 14 is provided with a comb sensor 111 for detecting the presence or absence of a wafer 1 of a predetermined material in the cassette 2 before the wafer posture alignment (when the wafer 1 is in a vertical state), so as not to mechanically interfere with the cassette 2 placed on the cassette stage device 13. The comb sensor 111 is attached to the side of the support table 141 on the roller 142a side (Y2 side) so as to be movable up and down relative to the cassette 2. It is movable between a detection position and a retreat position so as to be able to detect all sizes of wafers included in the detection parameters described later. This allows it to be commonly used for wafers of different diameters, improving versatility. Wafer mapping by the comb sensor 111 is performed in a different posture from that of the cassette 2 in wafer mapping by the reflective optical sensor 101, which will be described later. This allows the comb sensor 111 to be provided in a different position from that of the reflective optical sensor 101.

[0050] Comb sensor 111 is configured in a comb shape with multiple sensor pairs, each pair consisting of a light-emitting portion and a light-receiving portion, arranged in the direction in which wafers 1 are arranged, corresponding to the number of wafers 1 that can be accommodated in cassette 2. The light-emitting surface of the light-emitting portion is positioned so that the light-receiving surface of the light-receiving portion faces the pair of sensors to detect the presence or absence of each wafer 1. The light-emitting portion is configured, for example, by a light-emitting diode, and the light-receiving portion is configured, for example, by a phototransistor.

[0051] The light-emitting unit is disposed in the arrangement area of ​​the wafer 1, in this example, on one side of the storage area (slot) of each wafer 1 in the cassette 2. The light-receiving unit is disposed on the incident optical path of light from the light-emitting unit so as to face the light-emitting unit across the storage area of ​​the wafer 1. When the comb sensor 111 is in the raised state, the light-emitting unit and the light-receiving unit are disposed so that the light-emitting surface of the light-emitting unit faces a first surface of the wafer 1, and the light-receiving surface of the light-receiving unit faces a second surface of the wafer 1 opposite the first surface.

[0052] The comb sensor 111 is a transmission type sensor that irradiates the wafer 1 with reference light and detects the light transmitted through the wafer 1. In the case where the wafer 1 is not transparent (e.g., a silicon wafer), the light receiving unit receives (detects) the light emitted (reference light) from the light emitting unit when the wafer 1 is not present, and does not receive (detect) the light emitted (reference light) from the light emitting unit when the wafer 1 is present. This makes it possible to detect the presence or absence of the wafer 1. The presence or absence of the wafer is actually determined by threshold processing of the amount of received light designed for silicon wafers. Note that, in the case where the wafer 1 is a transparent wafer (e.g., a quartz wafer), the amount of transmitted light received exceeds the threshold, so the presence or absence of the wafer cannot be determined. In addition, detection of SiC wafers, which have a transmittance between silicon and quartz, is not guaranteed. In addition, there is no space left in the opening at the bottom of the cassette to accommodate a comb sensor designed for SiC wafers.

[0053] (2) Substrate processing Next, a substrate processing method using the reaction tube 31 of the processing apparatus 10 will be described with reference to Figures 7A and 7B. In the substrate processing method described here, one process of a manufacturing process of a semiconductor device, for example, a film formation process for forming a film on a wafer 1, will be described as an example using the reaction tube 31 of the processing apparatus 10 described above. In the following description, the operation of each part constituting the processing apparatus 10 is controlled by a controller 121.

[0054] (Cassette input: S20) Unprocessed wafers 1 are loaded in the cassette 2, and the cassette 2 is carried to the front of the housing 11 by an external carrier device (not shown), and the cassette 2 is placed on the cassette stage device 13 of the cassette delivery unit 12. The wafers 1 in the cassette 2 are in a vertical state. At this time, the external delivery stage 47 of the cassette stage device 13 is in the upper position.

[0055] (Orientation flat check: S21) First, with external receiving stage 47 in the home position (upper position), reflective optical sensor 101 checks the orientation flat. The orientation flat check is performed by moving reflective optical sensor 101 to a position corresponding to the two optical paths LP. If the orientation flats are not aligned, the process moves to step S22. If the orientation flats of all wafers 1 are aligned, the orientation flat alignment (wafer alignment: S22) is skipped and the process moves to step S24.

[0056] (Wafer alignment: S22) After the external delivery stage 47 is lowered to a lower position by the air cylinder 52, the wafer 1 is aligned by the wafer position aligning device 14 using the orientation flat.

[0057] (Orientation flat check: S23) After external receiving stage 47 has been raised to the upper position, reflective optical sensor 101 checks the orientation flats as in step S21. If the orientation flats of all wafers 1 are aligned, the process proceeds to step S24. If the orientation flats are not aligned, the process returns to step S22 and the wafer alignment is restarted. However, if the number of retries reaches or exceeds a predetermined number N, the process proceeds to step S38. Note that before proceeding to step S38, one more retry may be made by moving the optical path of reflective optical sensor 101 slightly downward (reducing the precision of the orientation flat alignment).

[0058] (First stage rotation: S24) Next, the cassette stage device 13 rotates 90 degrees, which in turn rotates the cassette 2 90 degrees. The wafers 1 in the cassette 2 are placed in a horizontal position.

[0059] (Wafer mapping: S25) Next, as shown in Fig. 8, when the wafer 1 is in a horizontal state in the cassette stage device 13, the CZ drive shaft 171 and the CS drive shaft 172 are operated to move the reflective optical sensor 101 to a position behind (in the X2 direction) the reflector 106 of the cassette stage device 13. Then, the robot arm 18 is raised by the CZ drive shaft 171, so that the reflective optical sensor 101 scans the cassette 2 from below to above (resolution is 0.05 mm). The reflector 106 has the same structure as the reflector 105, and faces the opening on the bottom side of the cassette 2 facing the external receiving stage 47, and is provided near the wafer alignment hole 53 of the external receiving stage 47 so as not to interfere with the operation of the wafer posture alignment device 14. This ensures an optical path between the reflective optical sensor 101 and the reflector 106.

[0060] The reflective optical sensor 101 receives the return reflection from the reflector 106, so the received light intensity (amount of received light) is low where the wafer 1 is present and high where the wafer 1 is not present. This received light intensity is acquired as scan data. Note that the slot width of the cassette 2 is greater than the thickness of the wafer 1, so there are locations within the slot where the wafer 1 is not present. The scan data is subjected to threshold processing, and sections where the scan data is continuously below the threshold are extracted as detection data. The detection data corresponds to the thickness of the wafer 1. The threshold (for mapping) used here is common to all combinations of substrate size and material, and may be the same as the threshold used for confirming the orientation flat.

[0061] Based on the detection data for each slot, it is judged whether the wafer 1 in each slot is present (ON) / absent (OFF) / abnormal. If there is no detection data or if the position or thickness in the ZI-Z2 directions is outside the allowable range, it is judged to be an abnormal slot.

[0062] (Abnormality judgment: S26) If it is determined in step S25 that there is an abnormality, the process proceeds to step S38. If it is determined that there is no abnormality, the process proceeds to step S27.

[0063] (First cassette movement: S27) Next, the cassette 2 is held by the hand 173 of the robot arm 18 , and the cassette 2 is transferred to the cassette shelf 15 or the spare cassette shelf 16 by the hand 173 of the robot arm 18 .

[0064] (Second cassette movement: S28) Next, the cassette 2 is transferred by the hand 173 of the robot arm 18 from the cassette shelf 15 or the spare cassette shelf 16 to a transfer shelf located opposite the wafer transfer device 19 of the cassette shelf 15. Next, the process proceeds to step 29 in FIG. 7B.

[0065] (First wafer transfer: S29) The wafers 1 in the cassette 2 are in a horizontal state, and the wafers 1 in the cassette 2 placed on the transfer shelf are transferred to and loaded into the boat 25 by the wafer transfer device 19 .

[0066] (Boat Ascension: S30) Next, the boat 25 is loaded into the reaction tube 31 by the boat elevator 22 .

[0067] (Film formation process: S31) After the boat 25 has been carried into the reaction tube 31, the atmosphere in the processing chamber 32 is controlled so that the pressure in the processing chamber 32 is set to a predetermined value. In addition, the temperature in the processing chamber 32 is controlled to a predetermined value by a heater, and a source gas and a reactive gas, for example, are supplied into the processing chamber 32 to form a film on the wafer 1.

[0068] (Boat lowering: S32) After the film formation process, the boat 25 is removed (unloaded) from the reaction tube 31 by the boat elevator 22.

[0069] (Second wafer transfer: S33) Next, the processed wafers 1 in the boat 25 are transferred by the wafer transfer device 19 into the cassette 2 on the transfer shelf.

[0070] (Third cassette movement: S34) Next, the cassette 2 on the transfer shelf is transferred to the cassette shelf 15 or the spare cassette shelf 16 by the hand 173 of the robot arm 18 .

[0071] (4th cassette movement: S35) When the cassette 2 is to be carried out of the processing device 10 , the cassette 2 is transferred by the hand 173 of the robot arm 18 from the cassette shelf 15 or the spare cassette shelf 16 to the cassette stage device 13 of the cassette transfer unit 12 .

[0072] (2nd stage rotation: S36) Next, the cassette 2 is rotated 90 degrees by the cassette stage device 13 so that the access opening of the cassette 2 faces upward, and the wafer 1 is placed in a vertical position.

[0073] (Cassette removal: S37) Thereafter, the cassette 2 is transported outside the housing 11 by an external transport device.

[0074] (Alarm: S38) If it is determined in steps S23 and S26 that there is an abnormality, an alarm is issued.

[0075] (Cassette removal: S39) The alarm is released, and the cassette 2 is manually removed from the cassette stage device 13.

[0076] According to this aspect, one or more of the following effects can be obtained.

[0077] (a) The reflective optical sensor 101 can be moved to a position corresponding to the optical path, so that one sensor can detect a plurality of optical paths.

[0078] (b) Since the reflective optical sensor 101 can be moved to a position corresponding to the optical path, it is possible to check the orientation flats of wafers stored in a plurality of cassettes with one sensor.

[0079] (c) Since the position of the optical path can be changed according to the type of wafer by moving the reflective optical sensor 101, even if the dimensions of the orientation flat, etc. differ depending on the diameter or material of the wafer, it is possible to detect it with a single sensor by moving the reflective optical sensor 101.

[0080] (d) Since the position of the optical path can be changed by moving the reflective optical sensor 101, the reproducibility and accuracy of the orientation flat detection can be set arbitrarily, enabling highly accurate detection.

[0081] (e) Since the orientation flat is checked before the orientation flat is aligned, if the orientation flat is aligned, the orientation flat alignment operation can be skipped, thereby shortening the time it takes to insert the cassette.

[0082] (f) High-precision detection is possible and the precision of the orientation flat position is guaranteed, improving the reliability of wafer transfer.

[0083] (g) Since the reflective optical sensor 101 and the reflector 105 are used to check the orientation flat, the orientation identification part can be detected wherever it is visible from the outside.

[0084] (h) Since the reflective optical sensor 101 and reflector 105 are used to check the orientation flat, the wiring is simpler than for a transmission type sensor, making it easy to retrofit the sensor to an existing device.

[0085] A substrate processing step in the processing apparatus according to another embodiment will be described with reference to FIG.

[0086] (Cassette input: S40) As in step S20 of the above embodiment, unprocessed wafers 1 are loaded into the cassette 2, and the cassette 2 is carried to the front of the housing 11 by an external carrier device (not shown), and the cassette 2 is placed on the cassette stage device 13 of the cassette delivery unit 12. The wafers 1 in the cassette 2 are in a vertical state. At this time, the external delivery stage 47 of the cassette stage device 13 is in the home position.

[0087] (Cassette positioning: S41) The external receiving stage 47 moves backward (in the X2 direction) to dock the inserted cassette 2 with the internal receiving stage 46 in the upright state and position it.

[0088] (Orientation flat confirmed: S42) The orientation flats of the wafers 1 stored in the cassette 2 are checked by the reflective optical sensor 101. If the orientation flats of all the wafers 1 are aligned, the process moves to step S43a. If the orientation flats are not aligned, the process moves to step S43b.

[0089] (External transfer stage descent: 43a) The external receiving stage 47 is lowered to the lower position.

[0090] (Wafer mapping: S44a) The comb sensor 111 performs wafer mapping to detect the presence or absence of the wafer 1 in the cassette 2 for each slot.

[0091] (External transfer stage rise: 46a) The external delivery stage 47 is raised to the home position. The process proceeds to step S24 of the embodiment described above and shown in FIG.

[0092] If the wafer mapping by the reflective optical sensor 101 is determined to be ON in step S25 following step S24 (wafer mapping by the reflective optical sensor 101) and the wafer mapping by the comb sensor 111 is determined to be ON, the material of the wafer 1 is determined to be Si. If the wafer mapping by the reflective optical sensor 101 is determined to be ON and the wafer mapping by the comb sensor 111 is determined to be OFF, the material of the wafer 1 is determined to be SiC. If the wafer mapping by the reflective optical sensor 101 is determined to be OFF and the wafer mapping by the comb sensor 111 is determined to be OFF, it is determined that there is no wafer 1.

[0093] (External transfer stage descent: 43b) As in step 43a, the external transfer stage 47 is lowered to the lower position.

[0094] (Wafer mapping: S44b) Similar to step 43a, wafer mapping is performed by comb sensor 111.

[0095] (Wafer alignment: S45) As in step S22 of the above embodiment, the wafer 1 is aligned by the wafer attitude alignment device 14 using the orientation flat.

[0096] (External transfer stage rise: 46b) As in step 46a, the external transfer stage 47 is raised to the home position.

[0097] (Orientation flat confirmed: S47) The orientation flats are checked by the reflective optical sensor 101. If the orientation flats of all wafers 1 are aligned, the process proceeds to step S24 in the above-mentioned embodiment shown in Figure 7A. If the orientation flats are not aligned, the process proceeds to step S38 in the above-mentioned embodiment shown in Figure 7A. Note that in the wafer mapping in S25, the material may be determined by integrating the detection results of the comb sensor 111 in S44a and S44b. That is, if a wafer is detected by both the comb sensor 111 and the reflective optical sensor 101, it is determined to be an opaque wafer such as Si, and if it is detected only by the reflective optical sensor 101, it is determined to be a transparent wafer such as SiC.

[0098] In the above-mentioned several aspects, an example of forming a film using a batch-type substrate processing apparatus that processes a plurality of substrates at a time has been described. The present disclosure is not limited to the above-mentioned aspects, and can be suitably applied to, for example, a case where a film is formed using a single-wafer type substrate processing apparatus that processes one or several substrates at a time. In the above-mentioned aspects, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. The present disclosure is not limited to the above-mentioned aspects, and can be suitably applied to, for example, a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0099] When using these substrate processing apparatuses, each process can be performed under the same process procedures and conditions as in the above embodiment, and the same effects as in the above embodiment can be obtained. [Explanation of symbols]

[0100] 1. Wafer (substrate) 2. Cassette 13. Cassette stage device 15 Cassette shelf 17. Cassette transport robot 18 Robot arm (moving part) 101...Reflective optical sensor 105...Reflector 121... Controller (control unit)

Claims

1. a stage on which a cassette containing a plurality of substrates each having an orientation identifying portion is placed; a reflector provided at one end of a predetermined optical path that is set so that light can pass through the substrate without hitting the substrate when the orientation specifying portion of each of the plurality of substrates is oriented in a predetermined direction; a robot having a reflective optical sensor configured to irradiate light along the optical path and detect reflected light from the reflector, the robot transporting the cassette between the stage and a shelf provided within the apparatus; a control unit configured to be able to control the robot so that the reflective optical sensor moves to a position corresponding to the optical path when confirming that the orientation identification units of the plurality of substrates on the stage match a predetermined orientation; and A substrate cassette handling device comprising:

2. a plurality of stages are provided, each of which is configured to be capable of transferring a cassette to and from the outside of the apparatus; and one or more pairs of the optical paths are set for each stage; 2. The substrate cassette handling device according to claim 1, wherein the control unit moves the reflective optical sensor to the other end of the optical path set for the stage being checked, thereby allowing the reflective optical sensor to be used commonly for a plurality of stages.

3. 2. The substrate cassette handling device according to claim 1, wherein the control unit is configured to be able to change the position of the optical path depending on the type of the substrate.

4. The stage comprises: a cassette inversion mechanism for moving the cassette between a first position in which the cassette stores the substrates arranged horizontally and a second position in which the cassette stores the substrates arranged vertically; 2. The substrate cassette handling device according to claim 1, further comprising an orientation alignment mechanism which rotates the substrate within the cassette to align the orientation identifying portion when the cassette is in the first position.

5. 5. The substrate cassette handling device according to claim 4, wherein the robot picks up the cassette in the second attitude from below and transports it.

6. the robot has a hand for handling the cassette, a first axis for moving the hand in a front-to-rear direction of the device, a second axis for moving the hand in a left-to-right direction of the device, and a third axis for moving the hand in a up-down direction of the device, 2. The substrate cassette handling device according to claim 1, wherein said reflective optical sensor is provided on a movable part of said robot which is drivable on said second axis and said third axis but not drivable on said first axis.

7. the optical path is perpendicular to a surface of the substrate, and a plurality of optical paths are set for one of the cassettes on the stage; The substrate cassette handling device of claim 1, wherein the control unit is configured to move the reflective optical sensor to multiple positions corresponding to multiple optical paths to confirm whether the orientation identification units of multiple substrates are in a predetermined orientation.

8. 2. The substrate cassette handling device according to claim 1, wherein the reflector is configured as a corner cube or is configured so that reflected light is polarized at approximately 90 degrees with respect to incident light.

9. 2. The substrate cassette handling device of claim 1, wherein the reflective optical sensor is configured to irradiate light polarized in a first direction and sense the reflected light through a polarizing filter having an absorption axis in the first direction.

10. 2. The substrate cassette handling device of claim 1, wherein the control unit is configured to skip an orientation flat alignment operation when it is confirmed by sensing the reflected light that the orientation flats of multiple substrates are in a predetermined orientation.

11. The stage comprises: a cassette inverting mechanism that rotates the cassette between a first position in which the substrates are arranged horizontally and a second position in which the substrates are arranged vertically; an orientation alignment mechanism that rotates the substrate within the cassette while the cassette is in the first position to align an orientation identifying portion; 2. The substrate cassette handling device according to claim 1, further comprising a moving mechanism that holds the cassette in the first attitude movably between an upper position where the cassette can be rotated by a cassette inversion mechanism and a lower position where the cassette can be aligned by an orientation alignment mechanism.

12. 12. The substrate cassette handling device according to claim 11, wherein the optical path is disposed in a space formed between the cassette and the alignment mechanism when the cassette is held in an upper position by the moving mechanism.

13. a stage on which a cassette containing a plurality of substrates each having an orientation identifying portion is placed; a reflector provided at one end of a predetermined optical path that is set so that light can pass through the substrate without hitting the substrate when the orientation specifying portion of each of the plurality of substrates is oriented in a predetermined direction; a robot having a reflective optical sensor configured to irradiate light along the optical path and detect reflected light from the reflector, the robot transporting the cassette between the stage and a shelf provided within the apparatus; a control unit configured to be able to control the robot so that the reflective optical sensor moves to a position corresponding to the optical path when confirming that the orientation identification units of the plurality of substrates on the stage match a predetermined orientation; and A substrate processing apparatus comprising:

14. placing a cassette containing a plurality of substrates having orientation identification units on a stage; controlling a robot to transport the cassette between the stage and a shelf disposed within an apparatus; controlling the robot so that a reflective optical sensor provided on the robot is located at a position corresponding to a predetermined optical path that is set so that light can pass through the substrate without hitting the substrate when the orientation identification portions of the substrates on the stage are oriented in a predetermined direction; a step of irradiating light along the predetermined optical path by the reflective optical sensor and sensing reflected light from a reflector provided at one end of the predetermined optical path; A substrate processing method comprising the steps of:

15. 15. A method for manufacturing a semiconductor device, comprising: the substrate processing method according to claim 14; and processing the substrate in a processing chamber.

16. A step of placing a cassette containing a plurality of substrates each having an orientation identifying portion on a stage; controlling a robot to transport the cassette between the stage and a shelf provided within an apparatus; a step of controlling the robot so that a reflective optical sensor provided on the robot is located at a position corresponding to a predetermined optical path that is set so that light can pass through the substrate without hitting the substrate when the orientation identification portion of each of the substrates on the stage is oriented in a predetermined direction; a step of the reflective optical sensor irradiating light along the predetermined optical path and detecting reflected light from a reflector provided at one end of the predetermined optical path; A program for causing a computer to execute the above in a substrate processing apparatus.

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