Substrate transport device, substrate processing system and substrate processing method

Abstract

The present invention provides a substrate transport device, a substrate processing system, and a substrate processing method. In a substrate transport device that transports substrates in a reduced-pressure atmosphere, the position of the substrate can be constantly monitored. The substrate transport device of the present invention transports substrates to a substrate processing device in a reduced-pressure atmosphere, and includes: a substrate holding portion for holding the substrate; and a substrate measuring portion disposed on the substrate holding portion for measuring the position of the substrate relative to the substrate holding portion.

Description

Technical Field

[0001] The present disclosure relates to a substrate transport device, a substrate processing system and a substrate processing method. Background Art

[0002] Patent Document 1 discloses a substrate processing apparatus comprising a transport module for transporting wafers and a processing module for processing the wafers. A communication port is provided in the wall of the transport module, connecting the interior of the transport module with the interior of the processing module. A sensor for detecting the edge of the wafer is located in the communication port.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-108063 Summary of the Invention

[0006] Technical problem to be solved by the invention

[0007] According to the technology disclosed in the present invention, in a substrate transport device that transports substrates in a reduced-pressure atmosphere, the position of the substrate can be constantly monitored.

[0008] Technical means to solve the problem

[0009] One aspect of the present disclosure provides a substrate transporting device for transporting a substrate to a substrate processing device under a reduced pressure atmosphere, comprising: a substrate holding portion for holding the substrate; and a substrate measuring portion, which is arranged on the substrate holding portion and measures the position of the substrate relative to the substrate holding portion.

[0010] Effects of the Invention

[0011] According to the present disclosure, in a substrate transport device that transports substrates in a reduced-pressure atmosphere, the position of the substrate can be constantly monitored. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a plan view showing the schematic structure of a wafer processing system.

[0013] Figure 2 It is a perspective view showing a schematic structure of a wafer transfer device.

[0014] Figure 3 is a top view of the third and fourth arms.

[0015] Figure 4 is a side view of the third and fourth arms.

[0016] Figure 5 It is an explanatory diagram showing a state in which the position of the mounting table is measured by the mounting table measuring unit.

[0017] Figure 6 This is an explanatory diagram showing an example of the operation flow of the wafer transport device.

[0018] Figure 7 It is an explanatory diagram of the operation of the fork when teaching the wafer transport device.

[0019] Figure 8 These are explanatory diagrams showing the normal and abnormal states of the fork.

[0020] Figure 9 It is a top view of the third arm and the fourth arm of another embodiment.

[0021] Figure 10 It is a top view of the third arm and the fourth arm of another embodiment. DETAILED DESCRIPTION

[0022] In the manufacturing process of semiconductor devices, semiconductor wafers (substrates, hereinafter referred to as "wafers") need to be subjected to various processes, such as film formation and etching, under a reduced pressure atmosphere (vacuum atmosphere). To perform these various processes, a so-called clustered wafer processing system can be used, which is constructed by connecting multiple processing modules around a transport module that has a wafer handling device inside. The wafer handling device within the transport module is used to transport the wafer to each processing module, where the wafer undergoes the required processing.

[0023] Here, for example, if the wafer is not properly positioned on the mounting table of the processing module, the required processing cannot be performed on the wafer. Therefore, it is necessary to hold the wafer in the proper position on the transfer arm of the wafer transfer device and then transfer the wafer from the transfer arm to the required position on the mounting table.

[0024] In this regard, in the substrate processing device (wafer processing system) disclosed in patent document 1, a sensor for detecting the edge of the wafer is configured at the connecting port connecting the interior of the transport module and the interior of the process module. Thus, when the wafer held by the transport arm is moved into the process module via the connecting port, the position of the edge of the wafer can be determined by the sensor, and the center position of the wafer can be determined. Afterwards, the position of the wafer is corrected based on the deviation between the determined center position of the wafer and the required center position of the wafer. In this way, it is possible to transport the wafer to the required position on the mounting table of the process module.

[0025] However, in a wafer handling device, even in situations other than transporting wafers to a processing module, for example, to prevent transport failures, it is necessary to maintain the wafer in the proper position on the handling arm. Therefore, it is desirable to be able to monitor the wafer at all times while the wafer is being transported by the wafer handling device. However, in the substrate processing device disclosed in Patent Document 1, the wafer position can only be measured when the wafer passes through the communication port. The wafer position cannot be measured at other times. Therefore, there is room for improvement in existing wafer handling devices.

[0026] Using the technology disclosed herein, a substrate transport device that transports substrates in a reduced-pressure atmosphere can consistently monitor the position of substrates. Below, a wafer transport device serving as a substrate transport device according to this embodiment, a wafer processing system serving as a substrate processing system, and a wafer processing method serving as a substrate processing method are described with reference to the accompanying drawings. In this specification and the accompanying drawings, elements having substantially the same functional structure are denoted by the same reference numerals to omit duplicate descriptions.

[0027] Wafer Processing System Structure

[0028] First, the configuration of the wafer processing system according to this embodiment will be described. Figure 1 This is a top view schematically illustrating the structure of a wafer processing system 1. The wafer processing system 1 performs required processing, such as film formation and etching, on a wafer W serving as a substrate in a reduced pressure atmosphere (vacuum atmosphere). However, the structure of the wafer processing system 1 disclosed herein is not limited to this and can be arbitrarily selected.

[0029] like Figure 1 As shown, in the wafer processing system 1, the normal pressure section 10 and the reduced pressure section 11 are connected as a whole via load lock modules 20a and 20b. In the normal pressure section 10, a FOUP (front opening pod) 31, which can accommodate multiple wafers W, is loaded and unloaded under a normal pressure atmosphere (under atmospheric atmosphere), and the wafers W are then transported to and from the load lock modules 20a and 20b. In the reduced pressure section 11, the wafers W are subjected to the required processing under a reduced pressure atmosphere (under vacuum atmosphere), and the wafers W are then transported to and from the load lock modules 20a and 20b.

[0030] A mounting table 21 a for mounting wafers W is provided inside the loader lock module 20 a. The loader lock module 20 a temporarily holds wafers W on the mounting table 21 a so that wafers W conveyed from a loader module 30 described later in the normal pressure section 10 can be transferred to a transport module 40 described later in the reduced pressure section 11 .

[0031] The load lock module 20a is connected to the loading module 30, described later, via a gate valve 22a. Furthermore, the load lock module 20a is connected to the transport module 40, described later, via a gate valve 23a. The gate valves 22a and 23a ensure airtightness between the load lock module 20a and the loading module 30 and the transport module 40, while maintaining communication with each other.

[0032] The load lock module 20a is connected to a gas supply unit (not shown) for supplying gas and an exhaust unit (not shown) for exhausting gas. These gas supply and exhaust units enable switching between normal pressure and reduced pressure atmospheres. Specifically, the load lock module 20a is configured to allow for the proper transfer of wafers W between the normal pressure unit 10 (normal pressure atmosphere) and the reduced pressure unit 11 (reduced pressure atmosphere).

[0033] The load lock module 20 b has the same structure as the load lock module 20 a , that is, the load lock module 20 b includes a mounting table 21 b on which the wafer W is mounted, a gate valve 22 b on the loader module 30 side, and a gate valve 23 b on the transport module 40 side.

[0034] In addition, the number and arrangement of the load lock modules 20a and 20b are not limited to the present embodiment, and can be set arbitrarily.

[0035] The normal pressure section 10 includes a loading module 30 and a loading port 32. The loading module 30 is equipped with a wafer handling device (not shown). The loading port 32 is used to load a FOUP 31 capable of storing multiple wafers W. The loading module 30 is also called an EFEM (Equipment Front End Module).

[0036] The loading module 30 is composed of a rectangular housing, the interior of which is maintained at a normal pressure. A plurality of, for example, three, loading ports 32 are arranged side by side on one side of the housing, forming a long side of the loading module 30. Loading interlock modules 20a and 20b are arranged side by side on the other side of the housing, forming a long side of the loading module 30. Furthermore, a wafer handling device (not shown) capable of moving in the longitudinal direction of the loading module 30 is provided inside the housing. The wafer handling device is capable of transporting wafers W between the FOUP 31 placed on the loading port 32 and the loading interlock modules 20a and 20b.

[0037] The number and arrangement of the loading ports 32 are not limited to this embodiment and can be arbitrarily designed. Furthermore, the normal pressure section 10 may also be provided with a processing module for performing required processing on the wafer W under normal pressure, such as a module for performing alignment processing for adjusting the horizontal orientation of the wafer W.

[0038] The FOUP 31 stores a plurality of wafers W in a stacked manner at equal intervals, for example, 25 wafers W in one batch. The interior of the FOUP 31 placed on the load port 32 is filled with, for example, air or nitrogen and is sealed.

[0039] The decompression section 11 includes a transport module 40 and a processing module 41. The transport module 40 is used to transport wafers W, and the processing module 41 serves as a substrate processing device for performing desired processing on the wafers W. The interiors of the transport module 40 and the processing module 41 are each maintained in a reduced pressure atmosphere. Multiple, for example, four, processing modules 41 are provided within the transport module 40. The transport module 40 is also referred to as a VTM (Vacuum Transfer Module).

[0040] The transport module 40 consists of a housing with a polygonal interior—a hexagonal shape in the illustrated example—and is connected to the load-lock modules 20a and 20b via gate valves 23a and 23b as described above. Specifically, the load-lock modules 20a and 20b and four processing modules 41 are arranged on each side of the transport module 40. The transport module 40 then transfers wafers W loaded into the load-lock module 20a to one of the processing modules 41 for the desired processing, and then unloads the wafers W through the load-lock module 20b to the normal pressure section 10.

[0041] A wafer transport device 50 for transporting the wafer W to the processing module 41 is provided inside the transport module 40. The detailed structure of the wafer transport device 50 will be described later.

[0042] A mounting table 42 for mounting wafers W is provided within the processing module 41. The processing module 41 performs required processing, such as film formation and etching, on the wafers W mounted on the mounting table 42. Furthermore, a gas supply unit (not shown) for supplying processing gases, purge gases, and the like, and an exhaust unit (not shown) for exhausting gases are connected to the processing module 41.

[0043] The processing module 41 is connected to the transport module 40 via a gate valve 43. The gate valve 43 ensures airtightness between the transport module 40 and the processing module 41 while maintaining communication therewith.

[0044] In addition, the number and arrangement of the processing modules 41 provided in the transport module 40 and the types of processing performed by the processing modules 41 are not limited to the present embodiment and can be arbitrarily set.

[0045] The wafer processing system 1 is provided with a control unit 60. The control unit 60 is, for example, a computer including a CPU, memory, etc., and has a program storage unit (not shown). The program storage unit stores a program for controlling the processing of wafers W in the wafer processing system 1. The program can also be recorded on a computer-readable storage medium H and installed from the storage medium H into the control unit 60.

[0046] Wafer Processing in Wafer Processing Systems

[0047] The wafer processing system 1 of this embodiment is configured as described above. Next, wafer processing in the wafer processing system 1 will be described.

[0048] First, the FOUP 31 storing a plurality of wafers W is placed on the load port 32 .

[0049] Next, a wafer transport device (not shown) removes wafer W from FOUP 31 and loads it into load-lock module 20a. Once wafer W is loaded into load-lock module 20a and placed on stage 21a, gate valve 22a closes, sealing and depressurizing the interior of load-lock module 20a. Gate valve 23a then opens, allowing the interior of load-lock module 20a to communicate with the interior of transport module 40.

[0050] Next, after the load lock module 20 a is connected to the transport module 40 , the wafer transport device 50 is used to remove the wafer W from the load lock module 20 a and transport it into the transport module 40 .

[0051] Next, the gate valve 43 is opened, and the wafer W is loaded into the processing module 41 by the wafer transport device 50 and placed on the mounting table 42. The gate valve 43 is then closed, and the desired processing is performed on the wafer W. When the processing is completed, the gate valve 43 is opened, and the wafer W is unloaded from the processing module 41 by the wafer transport device 50. The gate valve 43 is then closed.

[0052] Next, the gate valve 23b is opened, and the wafer W is loaded into the load lock module 20b by the wafer transport device 50. After the wafer W is loaded into the load lock module 20b and placed on the mounting table 21b, the gate valve 23b is closed, the load lock module 20b is sealed, and is opened to the atmosphere.

[0053] Next, the wafer W is returned to and stored in the FOUP 31 by a wafer transport device (not shown). In this way, a series of wafer processing in the wafer processing system 1 is completed.

[0054] In this embodiment, the wafers W before processing are transported to the load-lock module 20a, and the wafers W after processing are transported to the load-lock module 20b. However, the transport destination of the wafers W can be arbitrary. For example, the wafers W before processing can be transported to the load-lock module 20b, and the wafers W after processing can be transported to the load-lock module 20a. Alternatively, for example, the wafers W before processing can be unloaded from the load-lock module 20a while the wafers W after processing are loaded into the load-lock module 20a.

[0055] Wafer transport system structure

[0056] Next, the configuration of the wafer transport device 50 will be described. Figure 2 It is a perspective view showing a schematic structure of the wafer transfer device 50 . Figure 3 is a top view of the third arm 113 and the fourth arm 114 described later, Figure 4 It is a side view of the third arm 113 and the fourth arm 114 described later.

[0057] like Figure 2 As shown, the wafer transport device 50 includes a transport arm 100 for holding and moving wafers, and a base 101 that supports the transport arm 100. A drive mechanism (not shown) is provided on the base 101 to drive the transport arm 100 to move upward, downward, and rotate. The drive mechanism includes an actuator such as a motor to generate a driving force for moving the transport arm 100 upward and downward and for horizontally rotating the transport arm 100.

[0058] The transport arm 100 is a multi-jointed arm having a link arm structure in which a plurality of, for example, four arms 111 , 112 , 113 , and 114 are connected.

[0059] The base end of the first arm 111 is connected to the base 101, and the front end is connected to the second arm 112. The base end of the second arm 112 is connected to the first arm 111, and the front end is connected to the third arm 113 and the fourth arm 114. The base ends of the third arm 113 and the fourth arm 114 are each connected to the second arm 112. The third arm 113 is arranged above the fourth arm 114.

[0060] A first joint 121 is provided between the root end of the first arm 111 and the base 101. A second joint 122 is provided between the root end of the second arm 112 and the front end of the first arm 111. A third joint 123 is provided between the root end of the third arm 113 and the front end of the second arm 112. A fourth joint 124 is provided between the root end of the fourth arm 114 and the front end of the second arm 112. The third joint 123 and the fourth joint 124 are provided at the same position when viewed from above. A driving mechanism (not shown) is provided inside each of these joints 121, 122, 123, 124. Through this driving mechanism, each arm 111, 112, 113, 114 is configured to be able to turn (rotate) around the joint 121, 122, 123, 124.

[0061] A hollow portion with a normal pressure atmosphere is formed inside each of the first arm 111 and the second arm 112. Various components are housed in each hollow portion. For example, cables (not shown) connected to the wafer measurement units 132 and 142 described later and cables (not shown) connected to the stage measurement units 133 and 143 are housed. For example, a motor (not shown) for driving the drive mechanism of the joints 121, 122, 123, and 124 and cables (not shown) connected to the motor are also housed. For example, a vibrometer (not shown) for measuring the vibration of the transport arm 100 and a thermometer (not shown) for measuring the temperature of the transport arm 100 are also housed. In addition, for example, an air supply unit (not shown) for supplying clean and dry air is housed in the hollow portions of the first arm 111 and the second arm 112. These components are not exposed to the outside of the arm. Therefore, there is no need to prepare cable ducts or the like on the outside of the wafer transport device 50 to cover these components in order to prevent them from being damaged by the corrosive atmosphere.

[0062] The third arm 113 includes a fork 130 (end effector) serving as a substrate holding portion and a hand 131 supporting the fork 130. The fork 130 is provided on the front end side of the third arm 113, and the root end is mounted on the hand 131. The front end of the fork 130 is branched into two, having a double-forked shape. A plurality of adsorption pads (not shown) are provided on the upper surface of the fork 130, and the fork 130 uses these plurality of adsorption pads to adsorb and hold the wafer W. The hand 131 is provided on the root end side of the third arm 113 and is mounted on the third joint 123. In addition, the shape of the fork 130 is not limited to this embodiment, and for example, it may also be a flat plate shape.

[0063] The fork 130 is provided with a wafer measuring unit 132 as a substrate measuring unit for measuring the position of the wafer W. The wafer measuring unit 132 uses, for example, a CMOS line array sensor and is capable of measuring the distance from the wafer measuring unit 132 to the wafer W. A plurality of wafer measuring units 132, for example, three, are provided on the upper surface of the fork 130. The configuration of these three wafer measuring units 132 is not particularly limited. In the example shown in the figure, two wafer measuring units 132 are provided at the root end of the branch portion of the fork 130, and one wafer measuring unit 132 is provided near the front end of the branch portion of the fork 130. The measurement results of the three wafer measuring units 132 are output to the control unit 60, for example, via wireless communication or wired communication. In the control unit 60, based on the measurement results of the three wafer measuring units 132, the position of the center of the wafer W relative to the fork 130 is calculated. Furthermore, the control unit 60 can also detect the presence or absence of the wafer W on the fork 130 based on the measurement results of the three wafer measurement units 132 .

[0064] As described above, the cables (not shown) connected to the wafer measurement unit 132 are provided in the hollow portions of the first arm 111 and the second arm 112 and are embedded in the third arm 113. Therefore, the cables are not exposed outside the arms.

[0065] The number of wafer measurement units 132 is not limited to that in this embodiment. For example, if the diameter of the wafer W is known in advance, two wafer measurement units 132 may be provided. In this case, the control unit 60 can calculate the center position of the wafer W based on the measurement results of the two wafer measurement units 132 and the diameter of the wafer W.

[0066] Alternatively, for example, if alignment processing, which is used to adjust the horizontal orientation of the wafer W, is not performed in the normal pressure section 10, the number of wafer measurement units 132 may be four. Without alignment processing, the wafer measurement unit 132 may be located in a notch of the wafer W, making it impossible for the wafer measurement unit 132 to detect the wafer W. Therefore, in such a case, the number of wafer measurement units 132 may be four.

[0067] The fork 130 is provided with a platform measuring unit 133 for measuring the positions of the platforms 21a and 21b for the interlock modules 20a and 20b and the platform 42 for the processing module 41. The platform measuring unit 133 uses, for example, a white light confocal displacement sensor to measure the distances from the platform measuring unit 133 to the platforms 21a, 21b, and 42. Two platform measuring units 133 are provided at the tips of the two branches of the fork 130.

[0068] As described above, the cables (not shown) connected to the stage measurement unit 133 are provided in the hollow portions of the first arm 111 and the second arm 112 and are embedded in the third arm 113. Therefore, the cables are not exposed to the outside of the arms.

[0069] Figure 5 This diagram illustrates how the position of the platform 42 is measured by the platform measuring unit 133. Two platform measuring units 133a and 133b measure the distances to the platform 42 at four measurement points, M1 to M4, located above the platform 42. Measurement points M1 and M2 are aligned in the direction of movement of the platform measuring unit 133a, while measurement points M3 and M4 are aligned in the direction of movement of the platform measuring unit 133b. While the fork 130 is moved relative to the platform 42, the platform measuring unit 133a sequentially measures the distances to the platform 42 at measurement points M1 and M2, while the platform measuring unit 133b sequentially measures the distances to the platform 42 at measurement points M3 and M4. The measurement results of the platform measuring units 133a and 133b are output to the control unit 60 via, for example, wireless or wired communication. The control unit 60 calculates the position of the center of the mounting table 42 relative to the fork 130 based on the measurement results of the mounting table measuring units 133 a and 133 b .

[0070] The number of measurement points on the stage 42 is not limited to that in this embodiment. For example, even if there are three measurement points, the center position of the stage 42 can be calculated by the control unit 60. However, if there are four measurement points, the center position of the stage 42 can be calculated more accurately.

[0071] The number of stage measuring units 133 is not limited to that in this embodiment. For example, if the diameter of the stage 42 is known in advance, a single stage measuring unit 133 may be provided. In this case, the control unit 60 can calculate the center position of the stage 42 based on the two measurement results of the stage 42 performed by the single stage measuring unit 133 and the diameter of the stage 42.

[0072] The placement of the platform measurement unit 133 is not limited to this embodiment. For example, the platform measurement unit 133 may be provided at the base of two branch portions on the fork 130. In this case, the length of the branch portions can be shortened. Furthermore, even if the platform 42 is measured at two points, the center position of the platform 42 can be calculated if the diameter of the platform 42 is known in advance as described above.

[0073] The fourth arm 114 also has the same structure as the third arm 113. Specifically, the fourth arm 114 includes a fork 140 as a substrate holding portion and a hand 141. Furthermore, the fork 140 is provided with three wafer measurement units 142 and two stage measurement units 143.

[0074] Wafer transport device operation

[0075] The wafer transfer device 50 of this embodiment is configured as described above. Next, the operation of the wafer transfer device 50 will be described. Figure 6 1 is an explanatory diagram showing an example of the operation flow of the wafer transport device 50. Figure 6 In FIG. 4 , “LLM20 a ” represents the load lock module 20 a , “VTM40 ” represents the transport module 40 , and “PM41 ” represents the processing module 41 .

[0076] This example describes the case where the wafer W is loaded and unloaded into and out of the load lock module 20a, and the wafer W is loaded and unloaded into and out of the processing module 41. In addition, in this example, as described above, the distance to the wafer W is measured using the wafer measurement units 132 and 142, and the center position of the wafer W is calculated in the control unit 60. However, for simplicity of description, it is described below that the center position of the wafer W is measured by the wafer measurement units 132 and 142. In addition, in this example, as described above, Figure 5 As shown, the distance to the platforms 21a, 21b, and 42 is measured using the platform measuring units 133 and 143, and the center positions of the platforms 21a, 21b, and 42 are calculated in the control unit 60. However, in order to simplify the description below, it is recorded that the center positions of the platforms 21a, 21b, and 42 are measured using the platform measuring units 133 and 143.

[0077] [Step S1]

[0078] First, the fork 130, which is not holding a wafer W, receives the unprocessed wafer W from the load lock module 20a. Specifically, the fork 130 is moved into the load lock module 20a. At this point, the center position of the stage 21a is measured using the stage measurement unit 133. Furthermore, the fork 140 holds a processed wafer W. The wafer measurement unit 142 then confirms the presence of the wafer W and measures its center position, thereby monitoring the wafer W.

[0079] [Step S2]

[0080] Next, based on the measured center position of the mounting table 21 a , the position of the fork 130 is corrected so that the fork 130 is arranged at a desired position relative to the mounting table 21 a .

[0081] [Step S3]

[0082] Next, the wafer W is received from the mounting table 21a by the fork 130. At this time, since the fork 130 is positioned at the desired position relative to the mounting table 21a, the wafer W can be held in the appropriate position on the fork 130. Then, the wafer measurement unit 132 is used to confirm the presence of the wafer W and measure the center position of the wafer W, and monitoring of the wafer W begins.

[0083] [Step S4]

[0084] Next, the fork 130 holding the wafer W is withdrawn from the load lock module 20 a .

[0085] [Step S5]

[0086] Next, in the transport module 40 , the operation of the fork 130 is changed to the operation of the fork 140 , and the processed wafer W held by the fork 140 is transferred to the load lock module 20 a .

[0087] [Step S6]

[0088] Next, the fork 140 is moved into the load lock module 20a. At this time, the center position of the mounting table 21a is measured using the mounting table measuring unit 143.

[0089] [Step S7]

[0090] Next, based on the measured center position of the mounting table 21 a , the position of the fork 140 is corrected so that the fork 140 is arranged at a desired position relative to the mounting table 21 a .

[0091] [Step S8]

[0092] Next, the wafer W is placed on the mounting table 21a from the fork 140. At this time, the center position of the wafer W is continuously measured using the wafer measurement unit 142 as described above starting from step S1. Then, the wafer W is placed on the mounting table 21a from the fork 140 so that the center position of the wafer W coincides with the center position of the mounting table 21a.

[0093] [Step S9]

[0094] Next, the fork 140 not holding the wafer W is withdrawn from the load lock module 20 a .

[0095] [Step S10]

[0096] Next, in the transport module 40 , the operation of the wafer transport device 50 is switched from loading and unloading the wafers W into and out of the load lock module 20 a to loading and unloading the wafers W into and out of the processing module 41 .

[0097] [Step S11]

[0098] First, the processed wafer W is received from the processing module 41 by the fork 140 that does not hold the wafer W. That is, the fork 140 is moved into the processing module 41. At this time, the center position of the mounting table 42 is measured using the mounting table measuring unit 143.

[0099] [Step S12]

[0100] Next, based on the measured center position of the mounting table 42 , the position of the fork 140 is corrected so that the fork 140 is arranged at a desired position relative to the mounting table 42 .

[0101] [Step S13]

[0102] Next, the fork 140 receives the wafer W from the mounting table 42. At this point, since the fork 140 is positioned at the desired position relative to the mounting table 42, the wafer W can be held at the appropriate position on the fork 140. The wafer measurement unit 142 then confirms the presence of the wafer W and measures the center position of the wafer W, thereby starting monitoring of the wafer W.

[0103] [Step S14]

[0104] Next, the fork 140 holding the wafer W is withdrawn from the processing module 41 .

[0105] [Step S15]

[0106] Next, in the transport module 40 , the operation of the fork 140 is changed to the operation of the fork 130 , and the wafer W before processing held by the fork 130 is transferred to the processing module 41 .

[0107] [Step S16]

[0108] Next, the fork 130 is moved into the processing module 41. At this time, the center position of the mounting table 42 is measured using the mounting table measuring unit 133.

[0109] [Step S17]

[0110] Next, based on the measured center position of the mounting table 42 , the position of the fork 130 is corrected so that the fork 130 is arranged at a desired position relative to the mounting table 42 .

[0111] [Step S18]

[0112] Next, the wafer W is placed from the fork 130 onto the mounting table 42. At this time, the center position of the wafer W is continuously measured using the wafer measurement unit 132 as described above starting from step S3. Then, the wafer W is placed from the fork 130 onto the mounting table 42 so that the center position of the wafer W coincides with the center position of the mounting table 42.

[0113] [Step S19]

[0114] Next, the fork 130 that is not holding the wafer W is withdrawn from the processing module 41 .

[0115] [Step S20]

[0116] Next, in the transport module 40 , the operation of the wafer transport device 50 is switched from loading and unloading wafers W into and out of the processing module 41 to loading and unloading wafers W into and out of the loader lock module 20 b .

[0117] According to the above embodiment, while the fork 130 is holding the wafer W in steps S3 to S17, the wafer measurement unit 132 confirms the presence of the wafer W and measures the center position of the wafer W, thereby continuously monitoring the wafer W. Similarly, while the fork 140 is holding the wafer W in steps S1 to S7 and S13 to S20, the wafer W is also continuously monitored. Therefore, the forks 130 and 140 can always properly hold the wafer W.

[0118] Here, for example, depending on the process in the processing module 41, the wafer W may be heated, which may cause thermal expansion of the wafer W. Furthermore, the peripheral edge of the wafer W may be removed, or a film may be formed on the upper surface of the wafer W. Since the diameter of the wafer W may change in this way, it is useful to constantly monitor the center position of the wafer W.

[0119] Furthermore, according to this embodiment, the position of the fork 130 is corrected based on the center position of the mounting table 21a in step S2. Similarly, the position of the fork 140 is corrected based on the center position of the mounting table 42 in step S12. Therefore, the forks 130 and 140 can receive the wafer W from the mounting tables 21a and 42 at the appropriate positions.

[0120] Furthermore, according to this embodiment, the position of fork 140 is corrected based on the center position of mounting table 21a in step S7, and then, in step S8, wafer W is placed from fork 140 onto mounting table 21a so that the center position of wafer W coincides with the center position of mounting table 21a. Similarly, the position of fork 130 is corrected based on the center position of mounting table 42 in step S17, and then, in step S18, wafer W is placed from fork 130 onto mounting table 42 so that the center position of wafer W coincides with the center position of mounting table 42. In this manner, by utilizing both the measurement results of wafer measurement units 132 and 142 and the measurement results of mounting table measurement units 133 and 143, wafer W can be placed from forks 140 and 130 onto appropriate positions on mounting tables 21a and 42 with high precision.

[0121] Here, for example, depending on the process in the processing module 41, a heat treatment may be performed, resulting in a change in the outer shape of the mounting table 42 or a movement of the mounting table 42. In such a case, according to this embodiment, since the center position of the mounting table 42 is measured, the wafer W can be placed at an appropriate position on the mounting table 42.

[0122] Furthermore, the position correction of the forks 130 and 140 in steps S2, S7, S12, and S17 of this embodiment can be omitted if, for example, the positional deviation of the forks 130 and 140 relative to the mounting tables 21a and 42 is within a predetermined allowable range. In this case, the throughput of wafer processing can be improved.

[0123] <Other Embodiments Regarding Operation of Wafer Transport Apparatus>

[0124] Next, another embodiment of the operation of the wafer transport device 50 will be described.

[0125] [Wafer transport equipment teaching]

[0126] Figure 7 It is an explanatory diagram of the operation of the fork 130 when teaching the wafer transport device 50 is performed. Figure 7 The Z direction in represents the vertical direction, and the R direction represents the horizontal movement direction of the fork 130. During the teaching of the wafer transport apparatus 50, the position (contact position) at which the fork 130 contacts the wafer W when the fork 130 receives the wafer W is stored.

[0127] In conventional teaching, for example, to align the fork's center position with the wafer's center position, a wafer-holding mark is placed on the fork, and the fork's movement is stored until the wafer is held at that mark. However, this teaching method makes it difficult to determine the vertical distance from the fork's initial position to the point where it contacts the wafer when the fork is moved vertically.

[0128] Therefore, in this embodiment, the wafer measurement unit 132 is used to grasp the contact position between the fork 130 and the wafer W. First, as shown in FIG. Figure 7 As shown, with the transport arm 100 extended to its maximum length, the fork 130 is spaced apart from the wafer W and positioned at an initial position P1 below the wafer W. Next, the fork 130 is moved horizontally and vertically until it contacts the wafer W at a contact position P2. At this point, the fork 130 can move in two ways, for example.

[0129] The first movement action C1 is Figure 7As shown by the dotted arrow, the horizontal movement speed of the fork 130 is made the same as the vertical movement speed and is constant. While the center position of the wafer W is measured by the wafer measurement unit 132, the fork 130 is moved in the horizontal and vertical directions. In this case, the fork 130 can be brought into contact with the wafer W while the center position of the fork 130 is made consistent with the center position of the wafer W, and the action of the fork 130 receiving the wafer W at the appropriate position can be reproduced. In this example, the horizontal movement speed of the fork 130 is the same as the vertical movement speed, and the horizontal movement distance is the same as the vertical movement distance. In this way, the vertical distance H from the initial position P1 to the contact position P2 of the fork 130 can be calculated based on the horizontal movement distance, and the contact position P2 of the fork 130 can be derived.

[0130] In the first movement C1, the horizontal and vertical movement speeds of the fork 130 may be different as long as the ratio is constant. The vertical distance H of the fork 130 can be calculated based on the ratio.

[0131] The second movement action C2 is as follows Figure 7 As shown by the single-dot dashed arrow, the fork 130 is moved alternately in a step-like manner in the horizontal direction and the vertical direction. For example, the distance of one movement in the horizontal direction is the same as the distance of one movement in the vertical direction. While measuring the center position of the wafer W using the wafer measurement unit 132, the fork 130 is repeatedly moved in the horizontal direction and the vertical direction. In this case, the fork 130 can be brought into contact with the wafer W while the center position of the fork 130 is made consistent with the center position of the wafer W, and the action of the fork 130 receiving the wafer W at the appropriate position can be reproduced. In this example, the horizontal movement distance of the fork 130 is the same as the vertical movement distance. In this way, the vertical distance H from the initial position P1 to the contact position P2 of the fork 130 can be calculated based on the horizontal movement distance, and the contact position P2 of the fork 130 can be derived.

[0132] In the second movement C2, the distance of one horizontal movement of the fork 130 and the distance of one vertical movement of the fork 130 may be different as long as the ratio is constant. The vertical distance H of the fork 130 can be calculated based on the ratio.

[0133] As described above, according to this embodiment, the contact position P2 between the fork 130 and the wafer W can be appropriately grasped using the wafer measurement unit 132 .

[0134] [Fork abnormality detection]

[0135] The above-described teaching method for the wafer transport device 50 can also be applied to detecting abnormalities in the fork 130 during normal operation. For example, when the wafer transport device 50 is repeatedly used, the vertical position of the fork 130 may change over time. If the vertical displacement of the fork 130 exceeds the allowable range, the fork 130 will not be able to properly receive the wafer W. Therefore, it is extremely important to detect such abnormal conditions of the fork 130.

[0136] Figure 8 1 is an explanatory diagram showing the normal and abnormal states of the fork 130. When the fork 130 is initially positioned at the normal position A, the vertical distance H from the fork 130 to the wafer W is the same as the vertical distance H derived during the teaching described above, or is within the allowable range relative to the vertical distance H. On the other hand, when the fork 130 is initially positioned at the abnormal position B1, which is lower than the normal position A, the vertical distance H1 from the fork 130 to the wafer W is outside the allowable range of the vertical distance H. Furthermore, when the fork 130 is initially positioned at the abnormal position B2, which is higher than the normal position A, the vertical distance H2 from the fork 130 to the wafer W is also outside the allowable range of the vertical distance H.

[0137] Therefore, when the fork 130 receives the wafer W, the same operation as that during the teaching is performed. That is, while the fork 130 is spaced apart from the wafer W, the center position of the wafer W is measured by the wafer measurement unit 132, and the fork 130 is moved in the horizontal and vertical directions so that the fork 130 contacts the wafer W. At this time, the movement of the fork 130 can be as follows: Figure 7 As shown by the dotted arrow (movement C1), the horizontal moving speed of the fork 130 is made equal to the vertical moving speed and is constant. Figure 7 As indicated by the dashed arrow (movement C2), the fork 130 is moved alternately in steps in the horizontal and vertical directions. Furthermore, by calculating the vertical distance from the initial position of the fork 130 to the contact position, the vertical displacement of the fork 130 can be determined. Consequently, it is possible to detect whether the initial position of the fork 130 is normal or abnormal.

[0138] [Feedback to regular operation]

[0139] The result of the abnormality detection of the fork 130 can be fed back into the movement of the fork 130 during normal operation.

[0140] Here, during normal operation, when the fork 130 receives the wafer W, there is a case where the fork 130 is first moved in the vertical direction at a first moving speed, and then the fork 130 is moved in the vertical direction at a second moving speed that is slower than the first moving speed. In this way, by moving the fork 130 at the faster first moving speed in the first half, the time required to receive the wafer W can be shortened. On the other hand, by moving the fork 130 at the slower second moving speed in the second half to receive the wafer W, the wafer W can be prevented from bouncing up when being received. However, even if the vertical speed of the fork 130 is controlled in this way, if the initial position of the fork 130 is abnormal, the fork 130 may move at the faster first moving speed when receiving the wafer W, and the wafer may not be prevented from bouncing up.

[0141] To this end, the vertical distance from the initial position to the contact position of the fork 130 is calculated as described above, and the vertical displacement of the fork 130 is grasped, thereby adjusting the height position at which the first moving speed is changed to the second moving speed. Specifically, for example, Figure 8 As shown, when the initial position of the fork 130 is the abnormal position B1, the vertical distance between the abnormal position B1 and the height position at which the first moving speed is to be changed to the second moving speed is longer than in the normal state. On the other hand, when the initial position of the fork 130 is the abnormal position B2, the vertical distance between the abnormal position B2 and the height position at which the first moving speed is to be changed to the second moving speed is shorter than in the normal state.

[0142] In this manner, by feeding back the result of abnormality detection of the fork 130 to the moving operation of the fork 130 , the time required for receiving the wafer W can be shortened while the wafer W can be prevented from bouncing up.

[0143] <Other Embodiments Regarding the Structure of the Wafer Transport Apparatus>

[0144] Next, another embodiment of the structure of the wafer transport device 50 will be described. In the forks 130 and 140 of the above embodiment, the wafer measurement unit 132 uses a CMOS linear array sensor, but the present invention is not limited to this. For example, Figure 9 As shown, the wafer measurement unit 132 may also use a camera as an imaging unit for imaging the wafer W, and measure the distance from the wafer measurement unit 132 to the wafer W based on the image captured by the camera. Alternatively, as shown in FIG. Figure 10 As shown, the wafer measurement unit 132 may also use an electrostatic capacitance distance sensor or a white light confocal sensor to measure the distance between the wafer measurement unit 132 and the wafer W. In either case, by measuring the distance between the wafer measurement unit 132 and the wafer W, the position of the center of the wafer W relative to the fork 130 can be measured.

[0145] The embodiments disclosed in the specification are merely illustrative in all respects and should not be considered restrictive. The above embodiments may be omitted, replaced, and modified in various ways without departing from the scope of the technical solution and the concept of the present invention.

[0146] Description of Reference Numerals

[0147] 1 Wafer processing system

[0148] 41 Processing Module

[0149] 50 Wafer handling device

[0150] 130, 140 fork

[0151] 132, 142 Wafer Measurement Department

[0152] W wafer.

Claims

1. A substrate processing method for processing a substrate using a substrate processing system, The substrate processing system comprises: a substrate processing device for processing the substrate under a reduced pressure atmosphere; and a substrate transport device for transporting the substrate to the substrate processing device under a reduced pressure atmosphere, In the substrate processing method, when the substrate is transported by the substrate transport device, the substrate is held by a substrate holding portion, and a substrate measuring portion provided on the substrate holding portion is used to measure the position of the substrate relative to the substrate holding portion. When receiving the substrate by the substrate holding portion, the substrate holding portion is moved in the horizontal direction and the vertical direction to bring the substrate holding portion into contact with the substrate while the position of the substrate is measured by the substrate measuring portion in a state where the substrate holding portion is spaced apart from the substrate. calculating a vertical distance between an initial position and a contact position of the substrate holding portion based on a horizontal velocity and a vertical velocity of the substrate holding portion; The calculated vertical distance is compared with a vertical distance in a normal state obtained in advance, and the displacement of the substrate holding portion is detected.

2. The substrate processing method according to claim 1, wherein: calculating the position of the center of the substrate relative to the substrate holding portion based on the measurement result of the substrate measuring portion, While the substrate is held by the substrate holding portion, the substrate is monitored based on the center position of the substrate.

3. The substrate processing method according to claim 1, wherein: When receiving the substrate using the substrate holding portion, the substrate holding portion is first moved in the vertical direction relative to the substrate at a first moving speed, and then the substrate holding portion is moved in the vertical direction at a second moving speed slower than the first moving speed. Based on the detected displacement of the substrate holding portion, a height position at which the first moving speed is to be changed to the second moving speed is adjusted.

4. The substrate processing method according to any one of claims 1 to 3, wherein: When teaching the substrate transport device, the substrate holding portion is moved in the horizontal and vertical directions to bring the substrate holding portion into contact with the substrate while the substrate measuring portion measures the position of the substrate with the substrate holding portion being spaced apart from the substrate. Based on the horizontal velocity and the vertical velocity of the substrate holding portion, the vertical distance between the initial position and the contact position of the substrate holding portion is calculated, and the contact position of the substrate holding portion is derived.

5. The substrate processing method according to any one of claims 1 to 3, wherein: The substrate processing device includes a mounting table for mounting the substrate, In the substrate processing method, when the substrate transport device enters the substrate processing apparatus, the position of the stage relative to the substrate holding portion is measured using a stage measuring portion provided on the substrate holding portion.

6. The substrate processing method according to claim 5, characterized in that: calculating the position of the center of the stage relative to the substrate holding portion based on the measurement result of the stage measuring portion, The position of the substrate holding portion is corrected based on the center position of the mounting table.

7. The substrate processing method according to claim 6, wherein: calculating the position of the center of the substrate relative to the substrate holding portion based on the measurement result of the substrate measuring portion, The substrate is placed on the mounting table based on the center position of the substrate and the center position of the mounting table.

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