Transport device and teaching method

Abstract

To provide a transport device equipped with a sensor at the tip of a fork and designed to further improve accuracy of substrate transport, and a teaching method, with the objective of expanding an automatic teaching function.SOLUTION: In a wafer processing system, a transport device comprises: a first fork 40 having first holding units 42, 43, sensors disposed in the first holding units, and a resolving shaft in a vertical direction; a second fork 50 having second holding units 52, 53, and a revolving shaft coaxial with the first fork; a transport chamber for accommodating a transport robot having both forks; and an optical sensor 37 disposed in the transport chamber and oriented in the vertical direction. First edge positions P2, P3 of the first holding units are detected by the optical sensor by turning the first fork, second edge positions on the same side as the first edge positions are detected by the optical sensor by turning the second fork, and a difference in a rotation angle of the first and second forks is calculated on the basis of the first and second edge positions.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a conveying device and a teaching method. [Background technology]

[0002] For example, as described in Patent Document 1, a transfer robot is known in which a plurality of arms for supporting substrates are coaxially supported. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-119927 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a transport device using a transport robot, the installation of a sensor at the tip of the fork is being considered for the purpose of expanding the automatic teaching function. The technology disclosed herein relates to a transfer device and a teaching method that can further improve the transfer accuracy of a substrate in such a transfer device. [Means for solving the problem]

[0005] One aspect of the present disclosure is a transport device for transporting a substrate, the transport device including: a first holding part having a mounting surface for the substrate; a sensor provided at a tip of the first holding part; a cable connected to the sensor and attached to only one of both sides in a width direction of the first holding part; a first fork having a rotation shaft extending in a vertical direction; a second holding part having a mounting surface for the substrate; a second fork having a rotation shaft coaxial with the first fork; a transport robot having the first fork and the second fork; a transport chamber capable of being decompressed to accommodate the transport robot; the control device includes an optical sensor oriented vertically, and a control device, and when the other side in the width direction of the first holding part to which the cable is not attached is defined as the non-wired side, the control device rotates the first fork to detect a first edge position that is the non-wired side edge position of the first holding part with the optical sensor, rotates the second fork to detect a second edge position that is the same side edge position as the non-wired side of the second holding part with the optical sensor, and calculates a rotation angle difference between the first fork and the second fork based on the first edge position and the second edge position. Effect of the Invention

[0006] According to the present disclosure, it is possible to provide a conveying device and a teaching method that can further improve the accuracy of conveying substrates in a conveying device equipped with sensors on the tips of forks for the purpose of expanding the automatic teaching function. [Brief description of the drawings]

[0007] [Figure 1] 1 is a plan view showing an outline of the configuration of a wafer processing system including a vacuum transfer device as a transfer device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective view showing an outline of the configuration of a transfer mechanism provided in the vacuum transfer device. [Diagram 3] FIG. 4 is a plan view showing a schematic view of the first fork as viewed from above in the vertical direction. [Figure 4] FIG. 4 is a cross-sectional view of the section AA in FIG. [Diagram 5] FIG. 4 is a plan view showing a schematic view of the second fork as viewed from above in the vertical direction. [Figure 6] 11 is a flow chart for explaining a teaching method by detecting an angle deviation of a fork. [Figure 7] 5A to 5C are diagrams for explaining the operation of the first fork and the second fork in the above teaching method. [Figure 8] FIG. 11 is a diagram showing a schematic diagram of an output history of an optical sensor when the first fork is rotating. [Figure 9] FIG. 11 is a diagram showing a schematic diagram of an output history of an optical sensor when the second fork is rotating. [Figure 10] 9 is superimposed on the output history of FIG. 8. FIG. [Figure 11] FIG. 13 is a schematic diagram showing the first fork and the second fork in a state in which an angular misalignment has occurred. [Figure 12] 13 is a flow chart for explaining another teaching method by detecting an angle deviation. [Figure 13] 13 is a diagram showing a schematic diagram of an output history of an optical sensor during rotation of the first fork in the teaching method of FIG. 12. FIG. [Figure 14] 13A and 13B are diagrams illustrating another example of wiring of the sensor cable. [Figure 15] 13A and 13B are diagrams illustrating another example of wiring of the sensor cable. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the substrate transport device according to the present embodiment will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are denoted by the same reference numerals, and duplicated description will be omitted.

[0009] <Wafer processing system> FIG. 1 is a plan view showing an outline of the configuration of a wafer processing system including a vacuum transfer device as a transfer device according to this embodiment.

[0010] A wafer processing system 1 in FIG. 1 performs predetermined processes, such as film formation, diffusion, and etching, on a wafer W as a substrate under reduced pressure. This wafer processing system 1 has a configuration in which a carrier station 10, into which a carrier C capable of accommodating a plurality of wafers W is loaded and unloaded, and a processing station 11 equipped with a plurality of various processing devices that perform predetermined processing on the wafers W under reduced pressure are integrally connected. The carrier station 10 and the processing station 11 are connected via two load lock devices 12 and 13.

[0011] The load lock devices 12 and 13 have load lock chambers 12a and 13a that are configured so that the interior of the chambers can be switched between an atmospheric pressure state and a vacuum state. The load lock devices 12 and 13 are provided so as to connect an atmospheric pressure transfer device 21 and a vacuum transfer device 30, which will be described later.

[0012] The carrier station 10 has a carrier mounting table 20 and an atmospheric pressure transfer device 21 provided adjacent to the carrier mounting table 20 .

[0013] The carrier placement table 20 is configured so that a plurality of carriers C, for example, three carriers C, can be placed side by side. The atmospheric pressure transfer device 21 has an atmospheric transfer chamber 22 whose interior is kept under atmospheric pressure. The atmospheric transfer chamber 22 is connected to the load lock chambers 12a, 13a of the load lock devices 12, 13 via gate valves G1, G2. A wafer transfer mechanism 23 is provided in the atmospheric transfer chamber 22. The wafer transfer mechanism 23 is configured to transfer a wafer W between the carrier C on the carrier mounting table 20 and the load lock chambers 12a, 13a under atmospheric pressure.

[0014] The carrier station 10 further includes an aligner 24 disposed adjacent to the atmospheric pressure transfer device 21. The aligner 24 recognizes a notch or the like of the wafer W and adjusts the orientation of the wafer W.

[0015] (Transportation device) The processing station 11 includes a vacuum transfer device 30 as a transfer device for transferring a substrate, and processing modules 60-63.

[0016] The vacuum transfer device 30 has a vacuum transfer chamber 31 whose interior is kept in a reduced pressure state (vacuum state). The vacuum transfer chamber 31 is made of a sealable housing, and is formed, for example, in a substantially polygonal shape (hexagonal shape in the illustrated example) in a plan view. The vacuum transfer chamber 31 is connected to the load lock chambers 12a and 13a of the load lock devices 12 and 13 via gate valves G3 and G4. The vacuum transfer chamber 31 is also connected to vacuum processing chambers 64 to 67, which will be described later, via gate valves G5 to G8, respectively. A wafer transfer mechanism 32 is provided in the vacuum transfer chamber 31 as a transfer mechanism for transferring a wafer W between the vacuum processing chambers 64 to 67, which will be described later, of the processing modules 60 to 63.

[0017] The wafer transfer mechanism 32 is a transfer robot having a base 33, arms 34 and 35, a first fork 40, and a second fork 50. FIG.

[0018] 2, one end of the arm 34 is rotatably attached to the base 33, and the other end of the arm 34 is attached to one end of another arm 35. A first fork 40 and a second fork 50 are attached to the other end of the arm 35.

[0019] The first fork 40 has a first arm 41 rotatably attached to the end of the arm 35, and two first holding parts 42, 43 as substrate holding parts extending from the first arm 41. The two first holding parts 42, 43 are formed by branching off from the first arm 41 and face each other. The first fork 40 having such a configuration is formed in a U-shape in a plan view.

[0020] The second fork 50 has a second arm 51 rotatably attached to the end of the arm 35, and two second holding parts 52, 53 extending from the second arm 51 as substrate holding parts. The two second holding parts 52, 53 are formed by branching off from the second arm 51 and face each other. The second fork 50 thus configured is formed in a U-shape in a plan view.

[0021] The shape of each of the forks 40 and 50 in a plan view is not limited to a U-shape as long as the forks 40 and 50 are capable of transporting the wafer W.

[0022] The second fork 50 is located below the first fork 40, and the second arm 51 of the second fork 50 is connected to the end of the arm 35 so as to form a rotation axis coaxial with the first arm 41 of the first fork 40. This rotation axis extends vertically, and the first fork 40 and the second fork 50 rotate horizontally at different heights around the coaxial rotation axis.

[0023] The distance between the upper surface (wafer mounting surface) of the first holding parts 42, 43 and the upper surface (wafer mounting surface) of the second holding parts 52, 53 is appropriately set so that the wafers held by each holding part 42, 43, 52, 53 do not interfere with each other, and is, for example, 10 mm.

[0024] The second fork 50 may be located above the first fork 40.

[0025] (Sensor cable wiring) Fig. 3 is a plan view showing the first fork 40 as viewed from above in the vertical direction. Fig. 4 is a cross-sectional view taken along line AA in Fig. 3. Note that hatching showing cut surfaces is omitted in Fig. 3. Fig. 5 is a plan view showing the second fork 50 as viewed from above in the vertical direction.

[0026] 3, a sensor 44 is provided at each of the tips of the two first holding parts 42, 43 of the first fork 40. These two sensors 44 are imaging sensors such as optical sensors or cameras, and are used for teaching the first fork 40 to place a wafer on a stage (not shown) in the processing module, and for various auto-teaching function extensions such as detecting the positions of the wafer, focus ring, etc. placed in the processing module.

[0027] Here, if a direction perpendicular to the extension direction of first arm 41 in plan view is referred to as the width direction (horizontal direction in FIG. 3), sensor 44 is located at an outer corner in the width direction of first holding parts 42, 43. For this reason, sensor cable 45 as a cable connected to sensor 44 is attached to the outer side of first holding parts 42, 43 in the width direction.

[0028] As shown in Fig. 4, a groove 46 capable of accommodating a sensor cable 45 is formed in a side surface 42a on the outer side in the width direction of the first holding portion 42. An adhesive member 47 is filled in the groove 46 with the sensor cable 45 accommodated therein, thereby fixing the sensor cable 45. The groove 46 is formed, for example, by a grinding process using a rotating grindstone, and extends along each of the side surfaces of the first arm 41 and the first holding portions 42 and 43 shown in Fig. 3.

[0029] By accommodating the sensor cable 45 in the groove 46 shown in Fig. 4, interference between the sensor cable 45 and other components during rotation of the first fork 40 can be suppressed. Note that the method of fixing the sensor cable 45 in the groove 46 is not limited to the method using the adhesive member 47. Also, Fig. 4 illustrates an example of the method of fixing the sensor cable 45 in one of the two first holding parts 42, but the sensor cable 45 is also fixed in the other first holding part 43 in a similar manner.

[0030] 5, no sensor used during teaching, such as the above-mentioned sensor 44, is installed in the second fork 50. For this reason, no sensor cable is wired to the outside or inside in the width direction in the second holding parts 52, 53.

[0031] Although the second fork 50 is not provided with a sensor for teaching, since the outer shapes of the first fork 40 and the second fork 50 are the same in a plan view, teaching of the second fork 50 can be performed by utilizing teaching information of the first fork 40. Specifically, for example, coordinate data in the horizontal plane of the first fork 40 when placing a wafer on the stage in the processing module obtained by teaching the first fork 40 is reflected in the second fork 50. This makes it possible to set the position coordinates in the horizontal plane when placing a wafer on the stage in the processing module for the second fork 50.

[0032] The wafer transfer mechanism (transfer robot) 32 equipped with the first fork 40 and the second fork 50 has been described above.

[0033] 1, a position detection mechanism 36 for detecting the position of the wafer W held by the first fork 40 or the second fork 50 on the wafer transfer path is provided in the vacuum transfer chamber 31. Based on the detection result by the position detection mechanism 36, a control device 70 (described later) calculates the positional deviation of the wafer W from a predetermined position on the first fork 40 or the second fork 50.

[0034] The position detection mechanism 36 is provided, for example, for each of the processing modules 60 to 63 described later. Specifically, the position detection mechanism 36 is provided, for example, on the transfer path of the wafer W to the processing module 60 near the gate valve G5, on the transfer path of the wafer W to the processing module 61 near the gate valve G6, on the transfer path of the wafer W to the processing module 62 near the gate valve G7, and on the transfer path of the wafer W to the processing module 63 near the gate valve G8.

[0035] Each position detection mechanism 36 has a pair of optical sensors 36a, 36b aligned along a corresponding gate valve (any of gate valves G5 to G8), for example. The optical sensors 36a, 36b are, for example, of a transmission type, and have a light-emitting unit and a light-receiving unit provided on the ceiling side and the floor side, respectively, in the vacuum transfer chamber 31. The optical sensors 36a, 36b are also installed so that their optical axes are oriented vertically, and the light-receiving unit is configured to receive light from the light-emitting unit.

[0036] While the wafer W passes between the light-emitting part and the light-receiving part of the optical sensors 36a, 36b, the light from the light-emitting part is blocked by the wafer W and the light-receiving part stops receiving light, and when the wafer W passes between the light-emitting part and the light-receiving part, the light-receiving part resumes receiving light. The length of the light-receiving stop period of the optical sensors 36a, 36b varies depending on the position of the wafer W relative to the first fork 40 or the second fork 50.

[0037] In other words, the posture in which the wafer W is placed on the first fork 40 or the second fork 50 can be identified from information on the length of the light reception stop period of the optical sensors 36a, 36b. A control device 70 described below calculates the positional deviation of the wafer W from a predetermined position on the first fork 40 or the second fork 50 based on the length of the light reception stop period of the optical sensors 36a, 36b. Note that the method of calculating the positional deviation of the wafer W from a predetermined position on the first fork 40 or the second fork 50 is not limited to this method, and other known methods can be used.

[0038] An optical sensor 37 for detecting the presence or absence of a wafer W on the first fork 40 or the second fork 50 located at the home position is provided in the vacuum transfer chamber 31. For example, if the home positions of the forks 40, 50 are positions indicated by two-dot chain lines in Fig. 1, the optical sensor 37 is located in the center surrounded by the U-shaped portions of the forks 40, 50 located at the home positions.

[0039] The optical sensor 37 is a transmission type sensor like the optical sensors 36a and 36b described above, and when a wafer W is present on the first fork 40 located at the home position, for example, the light from the light emitting unit is blocked by the wafer W, and light reception by the light receiving unit stops. On the other hand, when a wafer W is not present on the first fork 40 located at the home position, the light from the light emitting unit reaches the light receiving unit, and light reception by the light receiving unit resumes. Therefore, depending on the detection status of light reception by the light receiving unit of the optical sensor 37, it can be detected whether the wafer W is held on the first fork 40 or the second fork 50.

[0040] In the above example, transmission type sensors are used as the optical sensors 36a, 36b and the optical sensor 37, but reflection type sensors may be used as long as the desired detection function can be obtained.

[0041] 1, the processing modules 60-63 perform predetermined processes, such as a film formation process, a diffusion process, and an etching process, under reduced pressure on the wafer W. The processing modules 60-63 each have vacuum processing chambers 64-67 in which the predetermined processes are performed on the wafer W under reduced pressure. Among the processing modules 60-63, modules that perform processes according to the purpose of the wafer processing can be arbitrarily selected.

[0042] The wafer processing system 1 is provided with a control device 70. The control device 70 is, for example, a computer equipped with a processor such as a CPU, a memory, and the like, and has a program storage unit (not shown). The program storage unit stores a program including instructions for wafer processing by the wafer processing system 1.

[0043] For example, the program storage unit stores a program for controlling the rotational operation of each of the forks 40, 50 and a program for detecting the edge positions of each of the forks 40, 50 using an optical sensor. The program storage unit also stores, for example, a program for controlling the automatic teaching of each of the forks 40, 50. These programs may be recorded in a computer-readable storage medium M and installed from the storage medium M into the control device. The storage medium M may be a temporary storage medium or a non-temporary storage medium.

[0044] <Teaching method 1> Next, an example of a teaching method by detecting the angle deviation of the fork using the vacuum transport device will be described. The correction method described below is performed under the control of the control device 70.

[0045] Fig. 6 is a flow chart for explaining the teaching method by detecting the angle deviation. Fig. 7 is a diagram for explaining the operation of each fork 40, 50 when performing the teaching method. An optical sensor is used to detect the angle deviation, and in this embodiment, the optical sensor 37 shown in Fig. 1 is used.

[0046] (Step S10) First, as shown in Fig. 7(a), the first fork 40 and the second fork are moved to the angle check position. The angle check position is, for example, a position where the optical sensor 37 is present on the rotation path of the first holding parts 42, 43 when the first fork 40 rotates, and is a position where the optical axes of the first holding parts 42, 43 and the light emitting part of the optical sensor 37 can intersect when the first fork 40 rotates. Note that in Fig. 7(a), the second fork 40 is not shown because it is overlapped on top of the second fork, but the second fork is also moved to the angle check position like the first fork 40.

[0047] (Step S11) Next, as shown in Fig. 7(b), the first fork 40 is rotated clockwise. At this time, the widthwise outer portion of the first holding portion 42 passes the optical sensor 37, blocking the light of the optical sensor 37. As a result, as also shown in Fig. 8, the optical sensor 37 switches from a non-light-blocking state to a light-blocking state, and a signal is output from the optical sensor 37 to the control device 70. Based on this signal, the edge position P of the widthwise outer side of the first holding portion 42 is 1 can be detected.

[0048] 7(c), the inner portion of the first holding portion 42 in the width direction passes through the optical sensor 37, and the light of the optical sensor 37 is no longer blocked by the first holding portion 42. As a result, the optical sensor 37 switches from a light-blocking state to a light-non-blocking state, and the optical sensor Based on this signal, the widthwise inner edge position P 2 can be detected.

[0049] 7(d), the first fork 40 rotates further, causing the widthwise inner portion of the first holding portion 43 to pass the optical sensor 37. This blocks the light of the optical sensor 37 again, and the optical sensor 37 switches from the non-light-blocking state to the light-blocking state, causing the edge position P 3 can be detected.

[0050] 7(e), the widthwise outer portion of the first holding portion 43 passes through the optical sensor 37, and the light of the optical sensor 37 is no longer blocked by the first holding portion 43. This switches the optical sensor 37 from a light-blocking state to a light-non-blocking state, and the widthwise outer edge position P 4 can be detected.

[0051] By the above step S11, the edge positions P 1 ~P 4 You can get information on:

[0052] (Step S12) Next, as shown in FIG. 7(f), the second fork 50 is rotated clockwise in the same manner as the first fork 40. As a result, the two second holding portions 52, 53 of the second fork 50 pass the optical sensor 37, and the edge position P 1 ´~P 4 ' can be detected.

[0053] (Step S13) Next, the difference in the rotation angle between the first fork 40 and the second fork 50 is calculated. Specifically, the edge position P 1 ~P 4 and the edge position P of the second holding portions 52 and 53 of the second fork 50. 1 ´~P 4 However, when calculating the rotation angle difference, only the information on a specific edge position is used. The reason is as follows.

[0054] The above-mentioned sensor cable 45 is wired on the widthwise outer side of the first holding parts 42, 43 of the first fork 40. As described with reference to Fig. 4, the sensor cable 45 is fixed in the groove 46 on the widthwise outer side of the first holding part 42 by using an adhesive member 47, but it is practically difficult to form the adhesive member 47 so as not to protrude from the groove 46. Therefore, the position of the widthwise outer end of the first holding parts 42, 43 where the sensor cable 45 is wired is affected by the shape of the adhesive member 47.

[0055] That is, the edge position P of the first holding parts 42 and 43 1 ~P 4 Among them, the outer edge position P in the width direction corresponding to the wiring side of the sensor cable 45 1 , P 4is the end face of the adhesive member 47, and is not the edge position corresponding to the side surface of the first holding parts 42, 43, and therefore cannot guarantee high positional accuracy as position data for identifying the fork rotation angle detection position. In particular, if teaching is performed in a relatively high temperature environment, which is the actual transportation environment, the adhesive member 47 is affected by thermal expansion, which may lead to a deterioration in positional accuracy. On the other hand, the edge position P on the inner side in the width direction corresponding to the non-wiring side of the sensor cable 45 2 , P 3 Since no sensor cable is wired, the edge positions corresponding to the inner side surfaces of the first holding portions 42 and 43 in the width direction can be detected with high accuracy.

[0056] Therefore, in the teaching method according to the present embodiment, when calculating the rotation angle difference between the forks 40 and 50, the edge position P 2 , P 3 In the following description, the edge position P on the non-wiring side of the first holding parts 42 and 43 is used. 2 , P 3 is referred to as the "first edge position." Also, the edge position P 1 ´~P 4 ', the edge position P 2 ´, P 3 ' is referred to as the "second edge position."

[0057] In step S13, the first edge position P 2 , P 3 The set value of the rotation angle of the first fork 40 when the second edge position P 2 ´, P 3 The rotation angle difference is calculated from the set value of the rotation angle of the second fork 50 when the mark ' is detected. Hereinafter, a detailed explanation will be given with reference to Fig. 10. Fig. 10 is a diagram in which the output history of the optical sensor 37 when the first fork rotates shown in Fig. 8 and the output history of the optical sensor 37 when the second fork rotates shown in Fig. 9 are superimposed.

[0058] The first fork 40 and the second fork 50 rotate based on a control signal of a set value of the rotation angle output from the control device 70. Therefore, when no angular deviation occurs, the first edge position P 2 The set value of the rotation angle of the first fork 40 when the second edge position P 2 The set value of the rotation angle of the second fork 50 when the arrow D′ is detected coincides with the angle DEG1 shown in FIG.

[0059] On the other hand, in the process of assembling the wafer transport mechanism 32 shown in FIG. 1, an assembly error or the like may occur in the forks 40, 50. In this case, as shown in FIG. 2 Detection timing and second edge position P 2 Specifically, for example, when the set value of the rotation angle of the first fork 40 becomes the angle DEG1, the first edge position P 2 is detected, while the second edge position P 2 The point "DEG'" is detected when the set value of the rotation angle of the second fork 50 becomes the angle DEG2.

[0060] That is, the second edge position P 2 When there is no angular misalignment, the angle ' should be detected when the set value of the rotation angle becomes angle DEG1, but is instead detected at DEG2. Therefore, even if a set value of angle DEG1 is given to the second fork 50, the actual rotation angle of the second fork 50 may not be angle DEG1.

[0061] In this case, even if the same rotation angle setting value is given, as shown in FIG. 11, the second fork 50 has an angle deviation of a rotation angle difference θ with respect to the first fork 40. In step S13, the first edge position P 2 is detected, and the second edge position P of the second fork 50 is 2 The rotation angle difference θ is calculated based on the difference in angle DEG2 when the arrow ' is detected.

[0062] Since the first fork 40 and the second fork 50 have the same outer shape in a plan view, the first edge position P 2 and the second edge position P of the second holding portion 52 2 However, from the viewpoint of improving the calculation accuracy of the rotation angle difference θ, it is possible to calculate the rotation angle difference θ from the information of the first edge position P 3 and the second edge position P of the other second holding portion 53 3 It is preferable to use the information on the first edge position and the second edge position. This makes it possible to obtain multiple pieces of information on the first edge position and the second edge position, thereby improving the calculation accuracy of the rotation angle difference θ.

[0063] In the teaching method by detecting angular misalignment according to the present embodiment described above, a first edge position, which is the edge position of the first holding parts 42, 43 on the non-wired side of the sensor cable 45, and a second edge position, which is the edge position of the second holding parts 52, 53 on the same side as the non-wired side, are detected. The first edge position and the second edge position detected in this manner can be said to be the detection of the side of the first holding part and the side of the second holding part. Therefore, by calculating the rotation angle difference θ between the forks 40, 50 based on these first edge position and second edge position, the second fork 50 relative to the first fork 40 can be detected.

[0064] The information on the rotation angle difference θ calculated by the above-mentioned method is used, for example, in teaching the second fork 50. Specifically, after teaching the first fork 40, when using the teaching information for teaching the second fork 50, the coordinate data of the second fork 50 is corrected taking into account the rotation angle difference θ. This allows teaching to be performed taking into account the angle deviation due to the assembly error of each fork 40, 50, improving teaching accuracy. This allows the conveying accuracy of the substrate to be further improved in a conveying device having a fork 40 equipped with a sensor 44 at its tip for the purpose of expanding the automatic teaching function.

[0065] Furthermore, detection of fork angle deviation, correction of coordinate data, and teaching of each fork can all be performed automatically under the control of the control device 70. This means that teaching of each fork can be performed without the intervention of an operator, making it possible to perform teaching in a high-temperature environment like that during actual wafer processing. This allows teaching to be performed while taking into account the thermal expansion of parts such as gears used in the transport mechanism, improving teaching accuracy.

[0066] In the above-described steps S11 and S12, the first fork 40 and the second fork 50 are rotated clockwise, but they may be rotated counterclockwise. Also, for example, the order of steps S11 and S12 may be reversed. Moreover, when the rotation angle difference θ calculated in step S25 exceeds a predetermined threshold value (for example, ±1°), the operation of the vacuum transfer device 30 may be stopped and a warning may be issued to the operator.

[0067] <Teaching method 2> Next, another example of the teaching method by detecting the angle deviation will be described. Fig. 12 is a flow chart for explaining the method. Fig. 13 is a diagram showing a schematic diagram of the output history of the optical sensor when the first fork rotates in this teaching method.

[0068] (Step S20) First, similarly to step S10 described above, the first fork 40 and the second fork 50 are moved to the angle check position.

[0069] (Step S21) Next, in the same manner as in step S11 described above, the first fork 40 is rotated clockwise to position the edge P 1 ~P 4 This detects the first edge position P 2 , P 3 Get the.

[0070] (Step S22) Next, the first fork 40 is rotated counterclockwise. As a result, the edge positions P 11 ~P 14 is detected, and the first edge position P 12 , P 13 Get the.

[0071] By the above steps S21 and S22, the first edge position P when the first fork 40 is rotated clockwise is obtained as information on the first edge position. 2 , P 3 and the first edge position P when the first fork 40 is rotated counterclockwise. 12 , P 13 can be detected.

[0072] A gear is used as a part for rotating the first fork 40, but when changing the direction of rotation, the angle deviation may change due to the effect of gear backlash. For this reason, the first edge position P 2 , P 3 , P 12 , P 13 By detecting this, it is possible to detect the angle deviation taking into account the effect of backlash.

[0073] (Step S23) Next, as in step S12 described above, the second fork 50 is rotated clockwise to detect the edge positions of the second holding portions 52, 53, and information on the second edge position, which is the edge position on the same side as the non-wiring side of the sensor cable, is obtained.

[0074] (Step S24) Next, the second fork 50 is rotated counterclockwise, and the second edge positions of the second holding portions 52, 53 at this time are detected.

[0075] By performing steps S23 and S24 above, the second edge position when the second fork 50 is rotated clockwise and the second edge position when the second fork 50 is rotated counterclockwise can be detected as information on the second edge position.

[0076] (Step S25) Next, based on the first edge position and the second edge position detected by the above method, a rotation angle difference between the forks 40, 50 is calculated. The rotation angle difference calculated here takes into account the effect of gear backlash.

[0077] Therefore, the accuracy of detecting the angle deviation is improved, and the accuracy of teaching each fork can also be further improved. In the example shown in Fig. 12, each fork is rotated clockwise and then counterclockwise, but it may be rotated in the reverse order. The order of steps S21 to S24 is not particularly limited, and the flow may proceed in the order of step S21, step S23, step S22, and step S24, for example.

[0078] <Modification> The optical sensor used to detect the angle misalignment may be the optical sensor 36a or the optical sensor 36b of the position detection mechanism 36 shown in Fig. 1. The optical sensors 36a and 36b are installed in the vicinity of each other in the processing modules 60 to 63. Therefore, when the optical sensors 36a and 36b detect the first edge position and the second edge position, the state of the wafer transfer mechanism 32 is close to the state in which the wafer W is transferred into the processing modules 60 to 63.

[0079] Therefore, by using the optical sensor 36a or the optical sensor 36b, it is possible to detect the angular deviation of the fork in a state close to the time when the wafer W is transferred into the processing modules 60 to 63. This makes it possible to improve the detection accuracy, and also improves the teaching accuracy.

[0080] In addition, when detecting an angle misalignment, both the optical sensor 36a and the optical sensor 36b may be used, which increases the number of edge positions detected as the first edge positions and the number of edge positions detected as the second edge positions, thereby improving the detection accuracy.

[0081] When the optical sensor 37 is used as the optical sensor for detecting the angular misalignment, the angular misalignment can be detected when the arms 34 and 35 of the wafer transport mechanism 32 are located at the home position. Therefore, the angular misalignment can be detected with the influence of the posture of the arms 34 and 35 reduced.

[0082] In the above example, as shown in Fig. 4, the sensor cable 45 is housed in the groove 46, but for example, as shown in Fig. 14, the sensor cable 45 may be exposed and wired from the side surface 42a of the first holding part 42. In the example of Fig. 14, the sensor cable 45 is fixed to the side surface 42a of the first holding part 42 by an adhesive member 47 filled in the groove 46. Furthermore, for example, as shown in Fig. 15, the sensor cable 45 may be wired to the bottom surface 42c of the first holding part 42. In the example of Fig. 15, the sensor cable 45 is fixed to the bottom surface 42c near the side surface 42a, so that a part of the sensor cable 45 is located outside the side surface 42a.

[0083] 14 and 15, the edge position of the wiring side of the first holding part 42 detected by the optical sensor is the detection of the outer shape of the sensor cable 45, and the side surface 42a on the outside in the width direction of the first holding part 42 cannot be detected as the edge position. On the other hand, the edge position of the non-wiring side of the first holding part 42 detected by the optical sensor is the detection of the side surface 42b on the inside in the width direction of the first holding part 42. That is, in both the wiring examples of FIG. 14 and FIG. 15, it is possible to detect an angle misalignment by using information on the edge position of the non-wiring side of the sensor cable 45, as in the teaching method by detecting an angle misalignment described above.

[0084] In the above example, the sensor cable 45 is wired on the outer side in the width direction of the first holding part 42, but it may be wired on the inner side in the width direction. In this case, the wired side is the inner side in the width direction and the non-wired side is the outer side in the width direction, so when detecting an angle misalignment, the outer edge positions in the width direction of the first holding part and the second holding part should be obtained as the first edge position and the second edge position.

[0085] That is, if the sensor cable 45 is wired to one of the widthwise sides of the first holding parts 42, 43 and no such sensor cable is wired to the other side, the teaching method by detecting the angle misalignment described above can be applied. However, when forming the groove 46 in the first holding part, it is easier to form the groove 46 on the outer side surface in the widthwise direction than on the inner side surface. Therefore, from the viewpoint of ease of processing the groove 46, it is preferable to wire the sensor cable 45 on the outer side in the widthwise direction of the first holding part.

[0086] In the above example, a sensor cable is not wired to the second holding parts 52, 53, but a sensor cable may be wired to the "same side as the wiring side" of the first holding parts 42, 43 in the second holding parts 52, 53. Even in this case, if a sensor cable is not wired to the "same side as the non-wiring side" of the first holding parts 42, 43 in the second holding parts 52, 53, it is possible to detect the first edge position on the non-wiring side of the first holding parts 42, 43 and the second edge position on the non-wiring side of the second holding parts 52, 53. For this reason, the teaching method by detecting the angle deviation described above can be applied.

[0087] The cables wired to the first holding portions 42, 43 or the cables that can be wired to the second holding portions 52, 53 may not be cables for sensors but may be cables used for other purposes.

[0088] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The above embodiments may be omitted, substituted, or modified in various forms without departing from the scope of the appended claims, the configuration examples belonging to the technical scope of the present disclosure described below, and the gist thereof. For example, the components of the above embodiments may be arbitrarily combined. From such an arbitrary combination, the actions and effects of each of the components related to the combination can be obtained as a matter of course, and other actions and effects that are obvious to a person skilled in the art from the description of this specification can be obtained.

[0089] In addition, the effects described in this specification are merely explanatory or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to a person skilled in the art from the description of this specification in addition to or in place of the above effects.

[0090] Note that the following configuration examples also fall within the technical scope of the present disclosure. (1) A transport device for transporting a substrate, comprising: a first fork including a first holding section having a mounting surface for the substrate, a sensor provided at a tip of the first holding section, a cable connected to the sensor and attached to only one of both sides in a width direction of the first holding section, and a rotating shaft extending in a vertical direction; a second fork having a second holding portion having a mounting surface for the substrate and a rotating shaft coaxial with the first fork; a transport robot having the first fork and the second fork; a transfer chamber that can be decompressed and that houses the transfer robot; an optical sensor provided in the transfer chamber and having an optical axis oriented in a vertical direction; A control device, When the other side of the first holding portion in the width direction to which the cable is not attached is defined as a non-wiring side, The control device rotates the first fork to detect a first edge position, which is the non-wired side edge position in the first holding portion, with the optical sensor, rotates the second fork to detect a second edge position, which is the same side edge position as the non-wired side in the second holding portion, with the optical sensor, and calculates a rotation angle difference between the first fork and the second fork based on the first edge position and the second edge position. (2) The conveying device according to (1), wherein a groove in which the cable is placed is formed on a side surface of the first holding portion on which the cable is wired. (3) The conveying device according to (2), wherein the wiring side is the outer side in the width direction of the first holding portion. (4) A conveying device described in any one of (1) to (3), wherein the optical sensor is a sensor that detects whether the substrate is held by the first holding portion or the second holding portion at the home positions of the first fork and the second fork. (5) The transport device according to any one of (1) to (3), wherein the optical sensor is a sensor that detects a positional deviation of the substrate held by the first holding part or the second holding part from a predetermined position. (6) A conveying device described in any of (1) to (5), wherein, when detecting the first edge position, the control device detects the first edge position when the first fork is rotated clockwise and the first edge position when the first fork is rotated counterclockwise, and, when detecting the second edge position, the control device detects the second edge position when the second fork is rotated clockwise and the second edge position when the second fork is rotated counterclockwise. (7) A teaching method for a transfer device that transfers a substrate, comprising: The conveying device is a first fork including a first holding section having a mounting surface for the substrate, a sensor provided at a tip of the first holding section, a cable connected to the sensor and attached to only one of both sides in a width direction of the first holding section, and a rotating shaft extending in a vertical direction; a second fork having a second holding portion having a mounting surface for the substrate and a rotating shaft coaxial with the first fork; a transport robot having the first fork and the second fork; a transfer chamber that can be decompressed and that houses the transfer robot; an optical sensor provided in the transfer chamber and having an optical axis oriented in a vertical direction; A control device, When the other side of the first holding portion in the width direction to which the cable is not attached is defined as a non-wiring side, rotating the first fork to detect a first edge position, which is a non-wire side edge position of the first holding portion, with the optical sensor; rotating the second fork to detect a second edge position, which is an edge position on the same side as the non-wire side, of the second holding portion by the optical sensor; and calculating a rotation angle difference between the first fork and the second fork based on the first edge position and the second edge position. (8) The teaching method described in (7), wherein a groove for accommodating the cable is formed on a side surface of the first holding portion on the wiring side of the cable. (9) The teaching method described in (8), in which the wiring side is the outer side in the width direction of the first holding portion. (10) A teaching method described in any one of (7) to (9), wherein the optical sensor is a sensor that detects whether the substrate is held by the first holding portion or the second holding portion at the home positions of the first fork and the second fork. (11) A teaching method according to any one of (7) to (9), wherein the optical sensor is a sensor that detects a positional deviation of the substrate held by the first holding part or the second holding part from a predetermined position. (12) In the step of detecting the first edge position, the first edge position when the first fork is rotated clockwise and the first edge position when the first fork is rotated counterclockwise are detected, A teaching method according to any one of (7) to (11), wherein in the step of detecting the second edge position, the second edge position when the second fork is rotated clockwise and the second edge position when the second fork is rotated counterclockwise are detected. [Explanation of symbols]

[0091] 30 Vacuum transport device 31 Vacuum Transfer Chamber 32 Wafer transport mechanism (transport robot) 36a, 36b Optical sensor 37 Optical Sensors 40 First Fork 41 First Arm 42, 43 1st holding part 44 Sensors 45 Sensor cable 50 2nd Fork 51 Second Arm 52, 53 2nd holding part 70 Control device W wafer

Claims

1. A transport device for transporting a substrate, a first fork including a first holding portion having a mounting surface for the substrate, a sensor provided at a tip of the first holding portion, a cable connected to the sensor and attached to only one of both sides in a width direction of the first holding portion, and a rotating shaft extending in a vertical direction; a second fork having a second holding portion having a mounting surface for the substrate and a rotation shaft coaxial with the first fork; a transport robot having the first fork and the second fork; a transfer chamber that can be decompressed and that houses the transfer robot; an optical sensor provided in the transfer chamber and having an optical axis oriented in a vertical direction; A control device, When the other side of the first holding portion in the width direction to which the cable is not attached is defined as a non-wiring side, The control device rotates the first fork to detect a first edge position, which is the non-wire side edge position in the first holding portion, with the optical sensor, rotates the second fork to detect a second edge position, which is the same side edge position as the non-wire side in the second holding portion, with the optical sensor, and calculates a rotation angle difference between the first fork and the second fork based on the first edge position and the second edge position.

2. The conveying device according to claim 1 , wherein a groove in which the cable is placed is formed on a side surface of the first holding portion on a wiring side of the cable.

3. The transport device according to claim 2 , wherein the wiring side is an outer side in a width direction of the first holding portion.

4. The conveying device according to any one of claims 1 to 3, wherein the optical sensor is a sensor that detects whether the substrate is held by the first holding portion or the second holding portion at the home positions of the first fork and the second fork.

5. 4. The transport device according to claim 1, wherein the optical sensor is a sensor that detects a positional deviation of the substrate held by the first holding part or the second holding part from a predetermined position.

6. The conveying device according to any one of claims 1 to 3, wherein, when detecting the first edge position, the control device detects a first edge position when the first fork is rotated clockwise and a first edge position when the first fork is rotated counterclockwise, and, when detecting the second edge position, the control device detects a second edge position when the second fork is rotated clockwise and a second edge position when the second fork is rotated counterclockwise.

7. A teaching method for a transport device that transports a substrate, comprising: The conveying device is a first fork including a first holding portion having a mounting surface for the substrate, a sensor provided at a tip of the first holding portion, a cable connected to the sensor and attached to only one of both sides in a width direction of the first holding portion, and a rotating shaft extending in a vertical direction; a second fork having a second holding portion having a mounting surface for the substrate and a rotation shaft coaxial with the first fork; a transport robot having the first fork and the second fork; a transfer chamber that can be decompressed and that houses the transfer robot; an optical sensor provided in the transfer chamber and having an optical axis oriented in a vertical direction; A control device, When the other side of the first holding portion in the width direction to which the cable is not attached is defined as a non-wiring side, a step of rotating the first fork and detecting a first edge position, which is a non-wire side edge position of the first holding portion, with the optical sensor; a step of rotating the second fork and detecting a second edge position, which is an edge position on the same side as the non-wiring side in the second holding portion, with the optical sensor; and calculating a rotation angle difference between the first fork and the second fork based on the first edge position and the second edge position.

8. 8. The teaching method according to claim 7, wherein a groove for accommodating the cable is formed on a side surface of the first holding portion on a wiring side of the cable.

9. The teaching method according to claim 8 , wherein the wiring side is an outer side in a width direction of the first holding part.

10. The teaching method according to any one of claims 7 to 9, wherein the optical sensor is a sensor that detects whether the substrate is held by the first holding portion or the second holding portion at the home positions of the first fork and the second fork.

11. The teaching method according to any one of claims 7 to 9, wherein the optical sensor is a sensor that detects a positional deviation of the substrate held by the first holding part or the second holding part from a predetermined position.

12. In the step of detecting the first edge position, a first edge position when the first fork is rotated clockwise and a first edge position when the first fork is rotated counterclockwise are detected, A teaching method according to any one of claims 7 to 9, wherein in the step of detecting the second edge position, the second edge position when the second fork is rotated clockwise and the second edge position when the second fork is rotated counterclockwise are respectively detected.

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