Substrate transport device

Abstract

To provide a substrate carrier device which can precisely detect the front-rear directional position of a substrate in a substrate storage unit.SOLUTION: A substrate carrying device TID has a hand 1, a moving mechanism 31, a lifting mechanism 32, a moving mechanism 33, and a detection unit 2. The moving mechanism 31 moves the hand 1 in the front-rear direction to cause the hand 1 to enter the substrate storage container or withdraw from the substrate storage unit. The lifting mechanism 32 lifts the hand 1 and rises the substrate W from the below by the hand 1. The detection unit 2 includes a light emitting unit 21, a light reception unit, and an operation unit 141. The light emitting unit 21 is provided so that a light emitting surface is located above the upper surface of a protrusion part 31 of the hand 1. The light reception unit is provided so that the light reception surface is located above the upper surface of the protrusion part 31 of the hand 1. An operation unit 141 determines the front-rear directional position of the substrate W on the basis of the amount of light received by the light reception unit and determines a moving adjustment amount to move the substrate W on the basis of the position.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present application relates to a substrate transport apparatus. [Background technology]

[0002] Substrate transport devices that remove substrates from cassettes storing the substrates have been proposed in the past (e.g., Patent Documents 1 to 3). The substrate transport device includes a hand on which the substrate is placed. The substrate transport device removes a substrate from the cassette by performing the following operations. That is, first, the substrate transport device adjusts the height position of the hand at a position facing the cassette. Specifically, the substrate transport device adjusts the height position of the hand so that it is positioned slightly below the substrate to be removed. The substrate transport device then moves the hand in the front-to-rear direction into the cassette. The substrate transport device stops the hand at a predetermined position directly below the substrate and then raises the hand. This allows the hand to lift the substrate. Next, the substrate transport device retracts the hand from the cassette. This allows the substrate to be removed from the cassette. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-33220 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-287783 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-88222 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the placement position of the substrate inside the cassette may shift. Specifically, the placement position of the substrate in the front-to-rear direction may shift from a specified reference position. When the placement position of the substrate shifts from the reference position, the relative positional relationship between the hand and the substrate also shifts. As a result, the substrate is not placed in an appropriate position relative to the hand. In other words, the hand cannot lift the substrate at the appropriate position, and the substrate cannot be removed appropriately.

[0005] Therefore, an object of the present application is to provide a substrate transport device that can detect the position of a substrate in a substrate container in the front-rear direction with high accuracy. [Means for solving the problem]

[0006] A first aspect of the substrate transport device is a substrate transport device that removes a substrate from a substrate container having an internal structure in which a plurality of substrates are stored in a horizontal position and stacked at intervals in the vertical direction, and transports the substrate to a substrate holding unit, the substrate transport device comprising: a hand; an advance / withdraw mechanism that moves the hand in a front-to-rear direction to move the hand into and out of the substrate container; a lifting mechanism that raises the hand and lifts the substrate from below with the hand; a movement mechanism that moves the hand to a position opposite the substrate container; and a mechanism that moves integrally with the hand and is located adjacent to the substrate in a measurement direction that intersects the front-to-rear direction when the hand is in an advanced state with the hand advanced into the substrate container. and a detection unit that detects the position of the substrate in the forward / backward direction in the approach state, the detection unit including a light-emitting unit and a light-receiving unit that are arranged facing each other in the measurement direction, and a calculation unit, the hand including fingers and protrusions that are provided on the fingers and support the underside of the substrate, the light-emitting unit is arranged so that its light-emitting surface is located higher than the upper surface of the protrusion, and the light-receiving unit is arranged so that its light-receiving surface is located higher than the upper surface of the protrusion, the light-emitting unit irradiates a band-shaped light whose width direction is the forward / backward direction toward the light-receiving unit, and the calculation unit determines the forward / backward position of the substrate based on the amount of light received by the light-receiving unit, and determines the position adjustment amount to move the substrate based on the position.

[0007] A second aspect of the substrate transport device is a substrate transport device that removes a substrate from a substrate container having an internal structure in which a plurality of substrates are stored in a horizontal position and stacked at intervals in the vertical direction, and transports the substrate to a substrate holding section, the substrate transport device comprising: a hand; an advance / withdraw mechanism that moves the hand in a front-to-rear direction to move the hand into and out of the substrate container; a lifting mechanism that raises the hand and lifts the substrate from below with the hand; a moving mechanism that moves integrally with the hand, and in an advanced state in which the advance / withdraw mechanism has moved the hand into the substrate container, and a detection unit that is provided at a position adjacent to the substrate in a measurement direction that intersects the front-to-rear direction and that detects the position of the substrate in the front-to-rear direction in the approaching state, the detection unit including a light-emitting unit and a light-receiving unit that are arranged facing each other in the measurement direction, and a calculation unit, the light-emitting unit irradiates a band-shaped light whose width direction is the front-to-rear direction toward the light-receiving unit, and the calculation unit calculates the ratio between the amount of light received by the light-receiving unit when the light from the light-emitting unit is not blocked by the substrate and the amount of light received by the light-receiving unit in the approaching state, and determines the front-to-rear position of the substrate based on the ratio and determines whether the position is within an acceptable range.

[0008] A third aspect of the substrate transport device is the substrate transport device according to the first or second aspect, wherein the light-emitting unit is provided at a different height position from the light-receiving unit.

[0009] A fourth aspect of the substrate transport device is a substrate transport device according to any one of the first to third aspects, wherein the substrate has a central portion and a peripheral portion that is more outer than the central portion, and the peripheral portion is thicker than the central portion.

[0010] A fifth aspect of the substrate transfer apparatus is the substrate transfer apparatus according to any one of the first to fourth aspects, wherein the hand is formed with at least two suction ports. [Effects of the Invention]

[0011] The position of the substrate in the substrate container in the front-rear direction can be detected with high accuracy. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram schematically illustrating an example of a configuration of a substrate processing apparatus. [Figure 2] FIG. 2 is a front view schematically showing an example of the configuration of a substrate container. [Figure 3] FIG. 2 is a side view schematically showing an example of the configuration of a substrate container. [Figure 4] FIG. 2 is a perspective view schematically illustrating an example of the configuration of a substrate. [Figure 5] FIG. 2 is a side view schematically illustrating an example of the configuration of a substrate transport device. [Figure 6] FIG. 2 is a top view schematically illustrating an example of the configuration of a substrate transport device. [Figure 7] FIG. 2 is a diagram schematically illustrating an example of the positional relationship between a substrate and a sensor. [Figure 8] FIG. 10 is a plan view showing a schematic example of a state in which part of light from a light-emitting portion is blocked by a substrate. [Figure 9] FIG. 10 is a plan view showing another schematic example of a state in which part of the light from the light-emitting portion is blocked by the substrate. [Figure 10] 10 is a flowchart illustrating an example of an operation of the substrate transport device. [Figure 11] 1A and 1B are diagrams schematically showing an example of the shape of a substrate stored in a substrate container. [Figure 12] 10 is a flowchart illustrating another example of the operation of the substrate transport apparatus. [Figure 13] 10 is a flowchart illustrating an example of an operation of the substrate transport device. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments will be described with reference to the accompanying drawings. Note that the drawings are schematic, and for the sake of convenience, components may be omitted or simplified as appropriate. Furthermore, the relative sizes and positions of components shown in the drawings are not necessarily accurately depicted and may be changed as appropriate.

[0014] In the following description, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions of them may be omitted to avoid duplication.

[0015] <General configuration of substrate processing apparatus> Fig. 1 is a plan view schematically showing an example of the configuration of a substrate processing apparatus. The substrate processing apparatus in Fig. 1 is an apparatus that forms a resist film or the like on a substrate (e.g., a semiconductor wafer) W and develops the exposed substrate W.

[0016] 1, the substrate processing apparatus includes an indexer unit 110, a processing unit 120, an interface unit 130, and a control unit 140. The control unit 140 controls various components of the substrate processing apparatus.

[0017] The control unit 140 is an electronic circuit and may include, for example, a data processing device and a storage medium. The data processing device may be, for example, an arithmetic processing device such as a CPU (Central Processor Unit). The storage medium may include a non-transitory storage medium (for example, a ROM (Read Only Memory) or a hard disk) and a temporary storage medium (for example, a RAM (Random Access Memory)). The non-transitory storage medium may store, for example, a program that defines the processing to be performed by the control unit 140. The processing device executes this program, allowing the control unit 140 to perform the processing defined in the program. Of course, some or all of the processing performed by the control unit 140 may be performed by hardware.

[0018] An indexer unit 110 and an interface unit 130 are provided adjacent to each other on both sides of the processing unit 120. An exposure machine EXP, which is an external device separate from the main device, is provided adjacent to the interface unit 130.

[0019] The indexer section 110 includes a plurality of (four in the figure) container placement tables 111 and an ID transport mechanism TID. The container placement tables 111 are arranged in a row, and one cassette C is placed on each cassette placement table 111.

[0020] The substrate container C may be a FOUP (Front Opening Unified Pod) that stores substrates W in a sealed state, or may be an SMIF (Standard Mechanical Interface) pod or an OC (Open Cassette), etc. In the substrate container C, multiple substrates W in a horizontal position are stacked vertically with spaces between them. The horizontal position here refers to a state in which the thickness direction of the substrates W is aligned vertically.

[0021] The ID transport mechanism TID is provided beside the container mounting table 111 so as to be horizontally movable in the arrangement direction of the substrate containers C, and can stop at a position facing each substrate container C. The ID transport mechanism TID includes a holding arm, and transfers substrates W to and from each substrate container C and the processing section 120. The ID transport mechanism TID removes substrates W from the substrate container C and transports them to the processing section 120, and stores substrates W received from the processing section 120 in the substrate container C.

[0022] The indexer unit 110 is provided with a mapping sensor (not shown) for detecting the presence or absence of substrates in each stage within the substrate container C. For example, the mapping sensor includes a light-emitting unit and a light-receiving unit. The light-emitting unit and the light-receiving unit are arranged facing each other in the arrangement direction of the multiple substrate containers C. The light-emitting unit irradiates light onto the light-receiving unit, and the light-receiving unit receives this light. The light-emitting unit and the light-receiving unit are integral with each other and are arranged to be movable horizontally and vertically, and can enter the interior of the substrate container C. Specifically, the light-emitting unit and the light-receiving unit enter the interior of the substrate container C at a position that sandwiches a portion of the substrate W in a plan view. When the light-emitting unit and the light-receiving unit are located at the same height as a stage, if a substrate W is placed on that stage, the light from the light-emitting unit is blocked by the substrate W, and if no substrate W is placed on that stage, the light from the light-emitting unit is received by the light-receiving unit.

[0023] Conversely, when the light-receiving unit does not receive light, it indicates that a substrate W is placed on that tier, and when the light-receiving unit receives light, it indicates that a substrate W is not placed on that tier. The light-emitting unit and the light-receiving unit rise from the lowest tier to the highest tier in the substrate container C, making it possible to detect the presence or absence of a substrate on each tier in the substrate container C. The detection result of the mapping sensor is output to the control unit 140. The control unit 140 controls the ID transport mechanism TID in accordance with the detection result of the mapping sensor.

[0024] The processing unit 120 processes the substrate W. In the example of FIG. 1, the processing unit 120 is divided into cells 121 and 122. The cell 121 includes a main transport mechanism T1, and the cell 122 includes a main transport mechanism T2. Each of the cells 121 and 122 is provided with a plurality of processing units. Although only the cells 121 and 122 are shown in the example of FIG. 1, the processing unit 120 may be provided with a plurality of cells 121 and 122 arranged vertically. That is, a cell similar to the cell 121 may be stacked above the cell 121, and a cell similar to the cell 122 may be stacked above the cell 122. In short, the processing unit 120 may have a multi-story structure. In the cell 121 (and cells on upper floors), a resist film or the like is formed on the substrate W, and in the cell 122 (and cells on upper floors), the substrate W is developed.

[0025] The cells 121 and 122 are arranged side by side and connected to each other to form a substrate processing row connecting the indexer section 110 and the interface section 130. This is the same for each story. These substrate processing rows are arranged approximately parallel to each other in the vertical direction. In other words, the processing section 120 is composed of substrate processing rows with a tiered structure.

[0026] The interface unit 130 is disposed between the processing unit 120 and the exposure machine EXP, and relays the substrate W between them.

[0027] For simplicity of explanation, the following description will focus on cells 121 and 122, omitting explanation of the cells on the upper floors. A transport space A1 for transporting substrates W is formed in cell 121. The transport space A1 is formed in a strip shape that passes through the center of cell 121 and is parallel to the arrangement direction of cells 121 and 122. The processing units of cell 121 include a coating processing unit 123 that applies a processing liquid to the substrate W, and a heat processing unit 124 that performs heat treatment on the substrate W. The coating processing unit 123 is arranged on one side of the transport space A1, and the heat processing unit 124 is arranged on the other side.

[0028] A plurality of coating processing units 123 are arranged side by side, each facing the transport space A1. In this embodiment, a plurality of coating processing units 123 are also arranged side by side in the vertical direction. For example, a total of four coating processing units 123 are arranged in two rows and two columns. The coating processing units 123 include an anti-reflection film coating processing unit that performs processing to form an anti-reflection film on the substrate W, and a resist film coating processing unit that performs processing to form a resist film on the substrate W. For example, the two coating processing units 123 on the lower row form an anti-reflection film on the substrate W, and the two coating processing units 123 on the upper row form a resist film on the substrate W.

[0029] A plurality of heat treatment units 124 are arranged side by side, each facing the transport space A1. In this embodiment, a plurality of heat treatment units 124 are also arranged side by side in the vertical direction. For example, three heat treatment units 124 can be arranged horizontally, and five heat treatment units 124 can be stacked vertically. Each heat treatment unit 124 includes a plate 125 on which a substrate W is placed. The heat treatment units 124 include a cooling unit that cools the substrate W, a heating and cooling unit that performs heating and cooling processes in succession, and an adhesion treatment unit that performs heat treatment in a hexamethylsilazane (HMDS) vapor atmosphere to improve adhesion between the substrate W and the coating. The heating and cooling unit has two plates 125 and includes a local transport mechanism (not shown) that moves the substrate W between the two plates 125. There are multiple of each type of heat treatment unit, and they are arranged at appropriate positions.

[0030] Receiver PASS1 is provided at the boundary between the indexer unit 110 and cell 121, and receiver PASS2 is provided at the boundary between cells 121 and 122. Receiver PASS1 relays substrates W between the indexer unit 110 and cell 121, and receiver PASS2 relays substrates W between cells 121 and 122. Receivers PASS1 and PASS2 each include a plurality of support pins that support the substrate W in a horizontal position. A horizontal position here means that the thickness direction of the substrate W is aligned with the vertical direction. Receiver PASS1 can place, for example, two substrates W on it. Receiver PASS1 has, for example, a two-tier structure, with one substrate W placed on each tier. One stage receives substrates W to be transported from the indexer section 110 to the cells 121, and the other stage receives substrates W to be transported from the cells 121 to the indexer section 110. The receiver PASS2 also has a two-stage configuration.

[0031] A main transport mechanism T1 is provided approximately in the center of the transport space A1. The main transport mechanism T1 transfers substrates W to and from each of the processing units, receivers PASS1 and PASS2 of the cell 121. In the example of FIG. 1, the main transport mechanism T1 includes two holding arms H1 and H2. Therefore, the main transport mechanism T1 can use one holding arm H1 to take out a substrate W from a target portion (e.g., a processing unit of the cell 121) while using the other holding arm H2 to transfer another substrate W to the target portion.

[0032] A transport space A2 for transporting the substrate W is formed in the cell 122. The transport space A2 is formed as an extension of the transport space A1.

[0033] The processing units of the cell 122 include a coating processing unit 127 that coats a processing liquid on a substrate, a heat processing unit 126 that performs heat processing on the substrate W, and an edge exposure unit (not shown) that exposes the peripheral edge of the substrate W. The coating processing unit 127 is arranged on one side of the transport space A2, and the heat processing unit 126 and the edge exposure unit are arranged on the other side. Here, the coating processing unit 127 is preferably arranged on the same side as the coating processing unit 123. Furthermore, the heat processing unit 126 and the edge exposure unit are preferably arranged in the same row as the heat processing unit 124.

[0034] In this embodiment, a plurality of coating processing units 127 are also arranged in the vertical direction. For example, a total of six coating processing units 127 are arranged in three columns and two rows. The coating processing units 127 include a developing processing unit that develops the substrate W, and a resist cover film coating processing unit that performs processing to form a resist cover film on the substrate W. For example, three coating processing units 127 in the lower row form a resist cover film on the substrate W, and three coating processing units 127 in the upper row develop the substrate W.

[0035] The thermal processing units 126 are arranged in a horizontal direction along the transport space A2 and stacked in a vertical direction. Each thermal processing unit 126 includes a heating unit for heating the substrate W and a cooling unit for cooling the substrate W.

[0036] The edge exposure unit is a single unit provided at a predetermined position and includes a rotary holder (not shown) that rotatably holds the substrate W, and a light irradiation unit (not shown) that exposes the peripheral edge of the substrate W held by the rotary holder.

[0037] A placement / buffer section P-BF is provided at the boundary between the cell 122 and the interface section 130. The placement / buffer section P-BF receives the substrate W to be transported from the cell 122 to the interface section 130.

[0038] The main transport mechanism T2 is provided approximately in the center of the transport space A2 in a plan view. The main transport mechanism T2 has the same configuration as the main transport mechanism T1. The main transport mechanism T2 transfers substrates W to and from each of the receiver PASS2, the coating processing unit 127, the thermal processing unit 126, the edge exposure unit, and the receiver / buffer unit P-BF.

[0039] The interface section 130 includes a cleaning processing block 131 and an unloading / loading block 132. A receiver PASS3 is provided at the boundary between the cleaning processing block 131 and the unloading / loading block 132. An example of the configuration of the receiver PASS3 is similar to that of the receivers PASS1 and PASS2. A receiver / cooling unit (not shown) is provided above or below the receiver PASS3. The receiver / cooling unit cools the substrate W to a temperature suitable for exposure.

[0040] An IF transport mechanism TIF is provided in the unloading / loading block 132. The IF transport mechanism TIF transports substrates W from the placement / cooling unit to the load part LPa of the exposure machine EXP, and also transports substrates W from the unloading part LPb of the exposure machine EXP to the receiver PASS3.

[0041] The cleaning processing block 131 includes two cleaning processing units 133a and 133b and two transport mechanisms T3a and T3b. The two cleaning processing units 133a and 133b are arranged to sandwich the pair of transport mechanisms T3a and T3b. The cleaning processing unit 133a cleans and dries the substrate W before exposure. A plurality of cleaning processing units 133a may be stacked in multiple stages. The transport mechanism T3a transports the substrate W from the placement / buffer section P-BF to the cleaning processing unit 133a, and transports the cleaned substrate W from the cleaning processing unit 133a to the placement / cooling unit.

[0042] The cleaning processing unit 133b cleans and dries the exposed substrate W. A plurality of cleaning processing units 133b may be stacked in multiple stages. The transport mechanism T3b transports the substrate W from the receiver PASS3 to the cleaning drying processing unit 133b, and then transports the cleaned substrate W from the cleaning drying processing unit 133b to the receiver / buffer unit P-BF.

[0043] In such a substrate processing system, a substrate W is processed as follows. That is, the substrate W taken out of the substrate container C is cooled by the cooling unit of the cell 121. After being cooled, the substrate W is subjected to a coating process by the anti-reflection film coating process unit of the cell 121. As a result, an anti-reflection film is formed on the surface of the substrate W. The substrate W on which the anti-reflection film has been formed is heated by the heating and cooling unit and then cooled. The cooled substrate W is subjected to a coating process by the resist film coating process unit. As a result, a resist film is formed on the surface of the substrate W. The substrate W on which the resist film has been formed is heated again by the heating and cooling unit and then cooled. The substrate W on which the resist film has been formed is subjected to a coating process by the resist cover film coating process unit of the cell 122. As a result, a resist cover film is formed on the surface of the substrate W. The substrate W on which the resist cover film has been formed is heated by the heating and cooling unit of the cell 122 and then cooled.

[0044] The peripheral edge of the cooled substrate W is exposed in the edge exposure unit of the cell 122. The substrate W, whose peripheral edge has been exposed, undergoes cleaning and drying processing in the cleaning processing unit 133a. The cleaned substrate W is cooled in the placement and cooling unit. The cooled substrate W is exposed in the external exposure machine EXP. The exposed substrate W undergoes cleaning and drying processing in the cleaning and drying processing unit 133b. The cleaned substrate W undergoes post-exposure baking processing in the heating and cooling unit of the cell 122. The baked substrate W is cooled in the cooling unit of the cell 122. The cooled substrate W undergoes development processing in the development processing unit. The developed substrate W is heated and then cooled in the heating and cooling unit. The cooled substrate W is transported to the substrate container C of the indexer section 110. In this manner, the substrate processing apparatus processes the substrate W.

[0045] <Substrate container> FIG. 2 is a front view schematically illustrating an example of the configuration of a substrate container C, and FIG. 3 is a side view illustrating an example of the configuration of a substrate container C. The substrate container C has, for example, a box-like shape that opens in one substantially horizontal direction (toward the front of the paper in FIG. 2). The substrate container C is placed on a container mounting table 111 so that its opening 51 faces the ID transport mechanism TID (see also FIG. 1). Protrusion supports 52 for supporting the underside of a substrate W are protruding from the inner surfaces of both opposing side walls 53 of the substrate container C. The protrusion supports 52 protrude inward from the inner surfaces of each side wall 53. The upper surfaces of the protrusion supports 52 are substantially horizontal. The protrusion supports 52 formed on both side walls 53 each support the left-right end of the substrate W. The left-right direction is the direction in which both side walls 53 of the substrate container C face each other.

[0046] A plurality of protrusion support portions 52 are provided at intervals in the vertical direction, and a plurality of substrates W are supported by the left and right protrusion support portions 52. The plurality of substrates W are stored in the substrate container C in a stacked state at intervals in the vertical direction.

[0047] 3 shows a configuration in which the substrate container C is a FOUP, and the substrate container C also includes a lid 54. The lid 54 opens and closes the opening 51. The indexer unit 110 is provided with a drive member for opening and closing the lid 54, and when the substrate container C is placed on the container placement table 111, the drive member opens the lid 54. As a result, the substrate container C opens to the side of the ID transport mechanism TID.

[0048] <Substrate> The substrate W is, for example, a semiconductor wafer and has a substantially disc shape. FIG. 4 is a perspective view schematically showing an example of the configuration of the substrate W. In the present embodiment, as an example, the substrate W has a central portion 91 and a peripheral portion 92 on the outer peripheral side of the central portion 91. The upper surface of the substrate W has a concave shape that is recessed at the central portion 91. Conversely, the substrate W has a shape in which the peripheral portion 92 protrudes upward with respect to the central portion 91. The central portion 91 has a substantially circular shape in plan view. The peripheral portion 92 has a substantially annular shape surrounding the central portion 91, and the periphery of the central portion 91 is connected to the inner surface of the peripheral portion 92. The lower surface of the substrate W is substantially flat. Therefore, the peripheral portion 92 of the substrate W is thicker than the central portion 91.

[0049] The diameter of the substrate W is, for example, about 300 mm, and the width (radial width) of the peripheral portion 92 is, for example, about 2 mm to 3 mm. The thickness of the peripheral portion 92 of the substrate W is, for example, about 800 μm, and the thickness of the central portion 91 of the substrate W is, for example, about 45 μm to 60 μm.

[0050] <Substrate transfer mechanism for ID> FIG. 5 is a side view schematically showing an example of the configuration of the transfer mechanism TID for ID, and FIG. 6 is a top view schematically showing an example of the configuration of the transfer mechanism TID for ID. Hereinafter, the transfer mechanism TID for ID is also referred to as a substrate transfer device TID. The substrate transfer device TID includes a hand 1 which is an example of a holding arm 13, a sensor (detection unit) 2, and a hand movement mechanism 3.

[0051] The hand 1 is a member for placing the substrate W. In the examples of FIGS. 5 and 6, the hand 1 includes a pair of fingers 11 and a connecting member 12. Each finger 11 has an elongated shape and is arranged substantially parallel to each other in plan view (that is, when viewed along the vertical direction). The upper surface of the finger 11 is substantially horizontal.

[0052] The connecting member 12 is a member that connects the base ends of the fingers 11 together. In the example of Figs. 5 and 6, the connecting member 12 has a long plate shape and is arranged so that its thickness direction is along the vertical direction. The connecting member 12 is formed integrally with the fingers 11 using the same material, for example. The tips of both fingers 11 are spaced apart from each other. This hand 1 has a U-shape in plan view.

[0053] In the examples of Figures 5 and 6, two protrusions 13 are provided on the upper surface of each finger 11. The protrusions 13 protrude upward from the upper surface of the finger 11. Each protrusion 13 has, for example, a substantially circular shape in plan view. A total of four protrusions 13 provided on a pair of fingers 11 are provided at the vertices of an imaginary rectangle in plan view. The upper surfaces of the protrusions 13 are substantially horizontal. The substrate W is placed on the upper surfaces of the protrusions 13. More specifically, the upper surface of each protrusion 13 abuts against the lower surface of the peripheral edge 92 of the substrate W to support the substrate W.

[0054] In the example of FIG. 6, a suction port 13a is formed on the upper surface of each protrusion 13. At least one suction port 13a is formed in each protrusion 13. In the example of FIG. 6, four protrusions 13 are provided, and therefore at least four suction ports 13a are formed in the hand 1. These suction ports 13a are connected to an external suction mechanism (not shown) via a suction path provided inside the hand 1. The suction mechanism creates a negative pressure in the suction ports 13a, allowing the hand 1 to suck the substrate W from below. This allows the hand 1 to hold the substrate W.

[0055] 6, the suction port 13a is located directly below the peripheral edge 92 of the substrate W. Therefore, the hand 1 can apply a suction force to the thick peripheral edge 92. This allows the hand 1 to stably hold the substrate W.

[0056] The hand moving mechanism 3 moves the hand 1 at least in the front-rear direction D1 and the vertical direction. Here, the hand moving mechanism 3 also moves the hand 1 in the circumferential direction about a predetermined rotation axis Q1. As a specific example, the hand moving mechanism 3 includes an advancing / retreating mechanism 31, an elevating mechanism 32, and a rotating mechanism 33. The advancing / retreating mechanism 31 is controlled by the control unit 140 and moves the hand 1 in the front-rear direction D1. The advancing / retreating mechanism 31 may have, for example, multiple articulated arms, or may have a ball screw structure. The advancing / retreating mechanism 31 is coupled to the connecting member 12 of the hand 1, for example.

[0057] The lifting mechanism 32 is controlled by the control unit 140 and moves the hand 1 in the vertical direction. In other words, the lifting mechanism 32 raises and lowers the hand 1. The lifting mechanism 32 has, for example, a ball screw structure. In the example of Fig. 5, the lifting mechanism 32 raises and lowers the advancing and retreating mechanism 31, thereby raising and lowering the hand 1.

[0058] The rotation mechanism 33 is controlled by the control unit 140 to rotate the hand 1 around a rotation axis Q1 extending in the vertical direction. As a result, the hand 1 moves in the circumferential direction about the rotation axis Q1. The rotation mechanism 33 has, for example, a motor. In the example of FIG. 5, the rotation mechanism 33 rotates the advancing / retreating mechanism 31, the lifting mechanism 32, and the hand 1 together. By rotating the hand 1 with the rotation mechanism 33, the orientation of the hand 1 can be changed. Referring also to FIG. 1, the rotation mechanism 33 moves the hand 1 between a state in which the hand 1 (holding arm 113) faces the substrate container C and a state in which the hand 1 faces the placement unit PASS1.

[0059] The advancing / retreating mechanism 31 is rotated by the rotating mechanism 33, so the forward / backward direction D1 in which the advancing / retreating mechanism 31 moves the hand 1 is the radial direction of the rotation axis Q1. The hand 1 is disposed so that the longitudinal direction of its fingers 11 is along the forward / backward direction D1.

[0060] Here, an overview will be given of the operation of the substrate transport device TID when removing a substrate W from a substrate container C. First, the rotation mechanism 33 rotates the empty hand 1 so that the hand 1 faces the substrate container C. Note that the empty hand 1 here refers to a hand 1 on which no substrate W is placed. Next, the lifting mechanism 32 adjusts the height position of the hand 1. Specifically, the lower surface of the substrate W to be removed (the position connecting the upper surfaces of the left and right protrusion support portions 52) is set as a reference height position, and the lifting mechanism 32 adjusts the height position of the hand 1 so that the hand 1 is positioned slightly below this reference height position. In FIG. 2, an example of the height position of the fingers 11 is shown by imaginary lines. Next, the advancing / retracting mechanism 31 moves the hand 1 forward to a predetermined stop position directly below the substrate W.

[0061] The example in Fig. 6 shows the substrate W placed at a specified reference position in the substrate container C. That is, Fig. 6 shows the substrate W and the hand 1 in an advanced state in which the hand 1 has advanced into the substrate container C. The example in Fig. 6 shows the hand 1 stopped at a predetermined stop position. As illustrated in Fig. 6, when the substrate W is placed at the specified reference position, the four protrusions 13 of the hand 1 face the underside of the peripheral edge 92 of the substrate W when the hand 1 is stopped at the stop position.

[0062] Next, the lifting mechanism 32 lifts the hand 1. As the hand 1 is lifted, the protrusions 13 of the hand 1 come into contact with the underside of the peripheral edge 92 of the substrate W and adhere to it, causing the hand 1 to hold the substrate. Thereafter, the lifting mechanism 32 further lifts the hand 1 slightly, and lifts the substrate W from the protrusion supports 52. Once the hand 1 has lifted the substrate W, the lifting mechanism 32 stops lifting. Next, the advancing / retracting mechanism 31 moves the hand 1 backward, thereby retracting the hand 1 with the substrate W placed thereon from the substrate container C. As described above, the substrate transport device TID can remove the substrate W from the substrate container C.

[0063] As described above, when the substrate W is placed at the reference position in the substrate container C, the protrusions 13 of the hand 1 come into contact with the peripheral edge 92 of the substrate W. Therefore, the hand 1 can stably hold the substrate W. On the other hand, if the placement position of the substrate W is significantly deviated from the reference position in the front-rear direction D1, the relative positional relationship between the substrate W and the hand 1 will also be displaced. For example, the protrusions 13 will come off the peripheral edge 92 of the substrate W, and the hand 1 will not be able to hold the substrate W properly.

[0064] Therefore, the substrate transport device TID is provided with a sensor 2 for detecting the position of the substrate W in the front-rear direction D1. The sensor 2 is provided so as to be movable integrally with the hand 1. In the example of FIGS. 5 and 6, the sensor 2 is provided on the finger 11. When the hand 1 is in an advanced state in which it has advanced into the substrate container C, the sensor 2 is adjacent to the substrate W stored in the substrate container C. More specifically, when the hand 1 is stopped at the above-mentioned stop position, the sensor 2 faces the end of the substrate W in the front-rear direction D1 in the measurement direction D2 in a plan view. The measurement direction D2 is a direction intersecting the front-rear direction D1, for example, a direction perpendicular to the front-rear direction D1. In other words, the position of the sensor 2 relative to the finger 11 is determined so that the sensor 2 faces the end of the substrate W in the measurement direction D2 in the above-mentioned state. In the example of FIG. 6, the sensor 2 is provided on the base end side (rear) of the finger 11 and faces the rear end of the substrate W in the measurement direction D2 in a plan view.

[0065] The sensor 2 detects the position of the substrate W in the front-to-rear direction D1 when the hand 1 has entered the substrate container C. That is, the sensor 2 measures the position of the substrate W in the front-to-rear direction D1 from a measurement direction D2 that intersects with the front-to-rear direction D1. Because it is easy to measure the position of the substrate W in the front-to-rear direction D1 in the measurement direction D2 that intersects with the front-to-rear direction D1, the sensor 2 can measure the position of the substrate W in the front-to-rear direction D1 with high measurement accuracy.

[0066] 5 and 6, the sensor 2 includes a light-emitting unit 21 and a light-receiving unit 22. The light-emitting unit 21 and the light-receiving unit 22 are arranged facing each other in the measurement direction D2. More specifically, the light-emitting unit 21 and the light-receiving unit 22 are provided in positions that sandwich the rear end of the substrate W in the measurement direction D2 in the approaching state. In other words, the light-emitting unit 21 is provided on the opposite side of the end of the substrate W from the light-receiving unit 22. In the example of FIG. 6, the light-emitting unit 21 is provided on one of the pair of fingers 11, and the light-receiving unit 22 is provided on the other of the pair of fingers 11.

[0067] The light-emitting unit 21 emits a band-shaped light (i.e., electromagnetic waves) whose width direction is the front-rear direction D1 toward the light-receiving unit 22. The light-emitting unit 21 has a light source such as a laser light source or a lamp light source. The wavelength of the light emitted by the light-emitting unit 21 is not particularly limited, but infrared light, for example, can be used.

[0068] The light receiving section 22 receives the light emitted from the light emitting section 21, and outputs an electrical signal (hereinafter referred to as a detection signal) indicating the amount of received light to the control section 140. The light receiving section 22 is also called a photodetector.

[0069] When the empty hand 1 is located outside the substrate container C, the light emitted from the light-emitting unit 21 is received as is by the light-receiving unit 22. Here, even when the advancing / retracting mechanism 31 causes the hand 1 to enter the substrate container C and stop it at a predetermined stop position, the light from the light-emitting unit 21 is received as is by the light-receiving unit 22 before the hand 1 is raised. FIG. 7 is a diagram schematically showing an example of the positional relationship between the substrate W and the sensor 2. FIG. 7 schematically shows an example of a cross section taken along line AA in FIG. 6. In FIG. 7, the sensor 2 when the hand 1 has stopped at the stop position is shown by a virtual line. In this state, the light-emitting unit 21 and the light-receiving unit 22 are located below the substrate W, and the light emitted from the light-emitting unit 21 is not blocked by the substrate W and is received by the light-receiving unit 22.

[0070] When the lifting mechanism 32 raises the hand 1, the light-emitting unit 21 and the light-receiving unit 22 also rise together with the hand 1. Therefore, as illustrated in FIG. 7, part of the light from the light-emitting unit 21 is eventually blocked by the rear end of the substrate W. FIG. 8 is a plan view showing a schematic example of how part of the light from the light-emitting unit 21 is blocked by the substrate W. FIG. 8 shows an example of this state when the substrate W is located at the reference position. As can be seen from FIG. 8, a front part of the strip-shaped light from the light-emitting unit 21 is irradiated onto the rear end of the substrate W and is blocked by the substrate W, whereas a rear part of the strip-shaped light is not blocked by the substrate W and proceeds directly to the light-receiving unit 22. Therefore, the rear part of the strip-shaped light is received by the light-receiving unit 22.

[0071] Fig. 9 is a plan view showing an example of the state when the substrate W is placed in the substrate container C and shifted rearward from the reference position. In Fig. 9, the substrate W placed in the reference position is shown by a virtual line. As can be seen from a comparison of Figs. 8 and 9, the amount of light received by the light receiving unit 22 changes depending on the position of the substrate W in the front-to-rear direction D1. Specifically, the more rearward the substrate W is shifted, the greater the amount of light blocked by the substrate W and the smaller the amount of light received by the light receiving unit 22.

[0072] Therefore, the calculation unit 141 (see FIG. 5) of the control unit 140 determines the position of the substrate W in the front-rear direction D1 based on the amount of light received by the light receiving unit 22. For example, the correspondence relationship between the position of the substrate W in the front-rear direction D1 and the amount of light received by the light receiving unit 22 is set in advance by simulation, experiment, or the like. Correspondence information indicating this correspondence relationship is stored in a storage medium of the control unit 140, for example, as a look-up table or a function.

[0073] The light receiving unit 22 outputs a detection signal indicating the detected amount of received light to the control unit 140. The calculation unit 141 determines the position of the substrate W in the front-rear direction D1 based on the amount of received light indicated by the detection signal and the correspondence relationship information stored in the storage medium. It can be said that the calculation unit 141, together with the light emitting unit 21 and the light receiving unit 22, constitutes the sensor 2.

[0074] In the above example, the calculation unit 141 is included in the control unit 140, but the calculation unit 141 may be provided separately from the control unit 140. The calculation unit 141 is an electronic circuit and may have the same configuration as the control unit 140, for example.

[0075] The control unit 140 determines the amount of adjustment for the position of the hand 1 in the front-rear direction D1 based on the position of the substrate W determined by the calculation unit 141. Specifically, the control unit 140 determines the amount of adjustment for the position of the hand 1 so that the four protrusions 13 abut against the underside of the peripheral edge 92 of the substrate W. The control unit 140 causes the advancing / retracting mechanism 31 to adjust the position of the hand 1 by the amount of adjustment. As a result, even if the substrate W is placed in the substrate container C displaced in the front-rear direction D1 from a specified reference position, the position of the hand 1 in the front-rear direction D1 is adjusted in accordance with the positional displacement of the substrate W. Therefore, the hand 1 can lift the substrate W appropriately.

[0076] Incidentally, since the position of the hand 1 needs to be adjusted before the hand 1 comes into contact with the underside of the substrate W, the position of the substrate W needs to be detected before the hand 1 comes into contact with the underside of the substrate W. In other words, before the hand 1 comes into contact with the underside of the substrate W, some of the light from the light-emitting unit 21 needs to be blocked by the substrate W. Therefore, the light-emitting unit 21 and the light-receiving unit 22 are provided so that their respective light-emitting surfaces and light-receiving surfaces are located at least above the upper surface of the protrusion 13 of the hand 1 (i.e., the placement surface on which the substrate W is placed).

[0077] <Unloading operation of the substrate transport device> 10 is a flowchart showing an example of the unloading operation of the substrate transport device TID with respect to the substrate container C. Initially, no substrate W is placed on the hand 1, and the hand 1 is positioned outside the substrate container C. First, the rotation mechanism 33 rotates the empty hand 1 to face the substrate container C (step S1). Next, the lifting mechanism 32 adjusts the height position of the hand 1 (step S2). Specifically, the lifting mechanism 32 moves the hand 1 to a height position slightly below the bottom surface of the substrate W to be removed.

[0078] Next, the sensor 2 measures the total amount of received light P1 (step S3). The total amount of received light P1 is the amount of light received by the light receiving unit 22 when the light from the light emitting unit 21 of the sensor 2 is not blocked by the substrate W. In specific operations, the control unit 140 first instructs the light emitting unit 21 to emit light, and the light emitting unit 21 emits light in accordance with the instruction. The light receiving unit 22 receives the light and outputs a detection signal indicating the amount of received light to the control unit 140. At this time, the light irradiated from the light emitting unit 21 is received directly by the light receiving unit 22. The control unit 140 stores this amount of received light in a storage medium as the total amount of received light P1.

[0079] Next, the advancing / retreating mechanism 31 moves the hand 1 forward and stops it at a predetermined stopping position (step S4). At this predetermined stopping position, the hand 1 has entered the substrate container C, and in a plan view, the light emitter 21 and the light receiver 22 are positioned on opposite sides of the rear end of the substrate W (see FIGS. 8 and 9). Here, it is assumed that the light from the light emitter 21 has not yet been blocked by the substrate W before the hand 1 is raised (see the imaginary line in FIG. 7). In this case, the detection of the total amount of received light P1 (step S3) may be performed with the hand 1 stopped at the stopping position. In other words, step S3 may be performed after step S4.

[0080] Next, the lifting mechanism 32 raises the hand 1 (step S5). Since the sensor 2 moves integrally with the hand 1, the sensor 2 also rises. Next, the calculation unit 141 calculates the ratio R1 (=P2 / P1) of the amount of light received by the light-receiving unit 22, P2, to the total amount of light received, P1, based on the detection signal input from the light-receiving unit 22 (step S6). When the light from the light-emitting unit 21 is not blocked by the substrate W, the ratio R1 is ideally 1.0. As the sensor 2 rises, some of the light from the light-emitting unit 21 is eventually blocked by the substrate W (see FIGS. 8 and 9), and the amount of light received, P2, of light received by the light-receiving unit 22 drops significantly. At this time, the amount of light received, P2, changes by more than a first predetermined value. In other words, the ratio R1 also drops by more than a second predetermined value.

[0081] The calculation unit 141 determines whether the ratio R1 is below a predetermined ratio reference value that is less than 1.0 (step S7). This ratio reference value is set in advance and stored in a storage medium of the control unit 140. The ratio reference value is a value that is less than 1.0 and is greater than the amount of light received by the light receiving unit 22 when the substrate W is positioned at the frontmost position in the substrate container C. The ratio reference value is a value obtained by subtracting a second predetermined value from 1.0.

[0082] During the period when the light from the light-emitting unit 21 has not yet been blocked by the substrate W, the ratio R1 is ideally 1.0, so the calculation unit 141 repeatedly executes a set of steps S6 and S7. When the sensor 2 rises and the light from the light-emitting unit 21 is blocked by the substrate W, the ratio R1 falls below the ratio reference value. When the ratio R1 falls below the ratio reference value, the calculation unit 141 determines the position of the substrate W in the front-rear direction D1 based on the ratio R1 (step S8). For example, the correspondence between the ratio R1 and the position of the substrate W in the front-rear direction D1 is set in advance by simulation, experiment, or the like. Correspondence information indicating this correspondence is stored in a storage medium, for example, as a look-up table or a function. The calculation unit 141 determines the position of the substrate W in the front-rear direction D1 based on the determined ratio R1 and the correspondence information stored in the storage medium.

[0083] Next, the control unit 140 determines whether the obtained position of the substrate W is within an allowable range (step S9). The allowable range refers to the allowable range of the position of the substrate W in the front-rear direction D1, and if the position is within this allowable range, the lifting mechanism 32 can raise the hand 1, so that the hand 1 can lift the substrate W at an appropriate position.

[0084] If the position of the substrate W is outside the allowable range, the control unit 140 calculates an adjustment amount for the hand 1 based on a comparison between the position of the substrate W and a reference position of the substrate W, and causes the advancing / retracting mechanism 31 to adjust the position of the hand 1 in the front-rear direction D1 based on the adjustment amount (step S10). Specifically, the control unit 140 calculates the difference between the calculated position of the substrate W and the reference position of the substrate W as the adjustment amount. The reference position of the substrate W is stored, for example, in a storage medium of the control unit 140.

[0085] When adjusting the position of the hand 1 in the front-rear direction D1, the lifting mechanism 32 may temporarily suspend the lifting of the hand 1. Then, after the advancing / retreating mechanism 31 adjusts the position of the hand 1, the lifting mechanism 32 lifts the hand 1 again.

[0086] On the other hand, if the position of the substrate W obtained by the calculation unit 141 is within the allowable range, the lifting mechanism 32 continues to lift the hand 1 without executing step S10.

[0087] When the hand 1 lifts the substrate W, the lifting mechanism 32 stops the lifting of the hand 1. Next, the advancing / retracting mechanism 31 moves the hand 1 backward to retract the hand 1 from the inside of the substrate container C (step S11).

[0088] As described above, according to the substrate transport device TID, the sensor 2 detects the position of the substrate W in the front-rear direction D1 during the unloading operation of the substrate W. Then, the substrate transport device TID moves the hand 1 to an appropriate position relative to the substrate W according to the detected position, and then raises the hand 1. Therefore, even if the substrate W is misaligned in the front-rear direction D1 within the substrate container C, the substrate transport device TID can appropriately unload the substrate W.

[0089] Moreover, in the above example, the position of the substrate W in the front-rear direction D1 can be detected by the simple light-emitting section 21 and light-receiving section 22.

[0090] In the above example, the substrate W has a thin central portion 91 and a thick peripheral portion 92, and the area to be supported (peripheral portion 92) is narrow. Therefore, the tolerance for positional deviation in the front-to-rear direction D1 between the substrate W and the hand 1 is small. Therefore, the substrate transport device TID, which can detect the position of the substrate W and adjust the position of the hand 1, is particularly useful for substrates W having a central portion 91 and peripheral portion 92.

[0091] <Height position of the light emitting unit and light receiving unit> In the example of Fig. 7, the light-emitting unit 21 is provided at a different height position from the light-receiving unit 22. In the example of Fig. 7, the light-emitting unit 21 is provided at a higher position than the light-receiving unit 22, but they may be provided at the same height position.

[0092] <Board deflection> Both left-right ends of the substrate W are supported by protruding support portions 52 inside the substrate container C. Therefore, the substrate W bends under its own weight with both ends as fulcrums. FIG. 11 is a diagram schematically showing an example of the shape of the substrate W stored in the substrate container C. In the example of FIG. 11, the substrate W bends so that its central portion is positioned lower than both ends. In other words, the substrate W bends into a downwardly convex shape. Note that, since only both ends of the substrate W are supported inside the substrate container C, the substrate W bends in a cross section viewed from the front-to-back direction D1 (FIG. 11), but the substrate W hardly bends in a cross section viewed from the left-to-right direction.

[0093] 11 also shows the sensor 2. In this embodiment, before the hand 1 and sensor 2 are raised, the light from the light-emitting unit 21 is not blocked by the substrate W. That is, the light from the light-emitting unit 21 travels below the substrate W and directly enters the light-receiving unit 22. As the hand 1 and sensor 2 are raised, the light from the light-emitting unit 21 eventually begins to be blocked by the substrate W. The height position of the light-emitting unit 21 when the light begins to be blocked by the substrate W decreases as the amount of bending of the substrate W increases. That is, the height position of the hand 1 when the amount of received light changes significantly decreases as the amount of bending of the substrate W increases. In other words, the height position of the hand 1 when the ratio R1 changes from 1.0 to a value less than the ratio reference value decreases as the amount of bending of the substrate W increases. The relationship between the height position of the hand 1 and the amount of bending of the substrate W can be preset, for example, by simulation or experiment. Therefore, correspondence information indicating the relationship between the height position and the amount of bending is stored in advance in a storage medium of the control unit 140.

[0094] The calculation unit 141 monitors the height position of the hand 1 when the amount of received light P2 significantly changes during the elevation of the hand 1 and the sensor 2, and calculates the amount of deflection of the substrate W based on the difference (distance) between that height position and the reference height position. FIG. 12 is a flowchart showing an example of the operation of the substrate transport device TID. In FIG. 12, step S12 is further executed compared to the flowchart of FIG. 10. In the example of FIG. 12, step S12 is executed when it is determined in step S7 that the ratio R1 is less than the ratio reference value. In step S12, the calculation unit 141 calculates the amount of deflection of the substrate W based on the height position of the hand 1. The height position of the hand 1 is calculated based on, for example, the elapsed time since the start of the elevation of the hand 1 and the sensor 2 and the elevation speed. Alternatively, a sensor for detecting the height position of the hand 1 may be provided. For example, if the lifting mechanism 32 has a motor, the sensor may be a so-called encoder that detects the rotation position of the motor. The calculation unit 141 calculates the amount of deflection of the substrate W based on the calculated height position and the correspondence relationship information stored in a storage medium.

[0095] Thereafter, in steps S8 to S11, the substrate W is removed by the substrate transfer device TID.

[0096] As described above, the substrate transport device TID can detect the amount of deflection of the substrate W when removing the substrate container C. Therefore, there is no need to separately provide a dedicated detector for detecting the amount of deflection, and the amount of deflection of the substrate W can be detected at low cost.

[0097] <Transfer to the substrate holder> 6, the hand 1 has a U-shape in a plan view and supports a peripheral edge portion 92 of the substrate W. Therefore, the center of the substrate W does not face the hand 1, and the substrate W can bend due to its own weight even when placed on the hand 1. Although the amount of bending of the substrate W on the hand 1 may differ from the amount of bending of the substrate W in the substrate container C, it is considered that the greater the amount of bending of the substrate W in the substrate container C, the greater the amount of bending of the substrate W on the hand 1. In other words, when the amount of bending of the substrate W in the substrate container C is large, the substrate W is relatively prone to bending, and therefore bends more on the hand 1.

[0098] The correspondence between the amount of deflection of the substrate W in the substrate container C and the amount of deflection of the substrate W on the hand 1 can also be set in advance by experiment, simulation, or the like. Correspondence information indicating this correspondence is also stored in the storage medium of the control unit 140, for example, as a look-up table or a function. Therefore, the calculation unit 141 can also determine the amount of deflection of the substrate W on the hand 1 based on the amount of deflection of the substrate W in the substrate container C. In short, the calculation unit 141 can determine the amount of deflection of the substrate W on the hand 1 based on the height position of the hand 1 when the amount of received light changes significantly.

[0099] When the substrate transport device TID transfers the substrate W to the receiver PASS1, the hand 1 is lowered to place the substrate W on the substrate holder of the receiver PASS1. The substrate holder has, for example, a plurality of support pins, which support the underside of the substrate W. For example, the support pins support the underside of at least the central portion 91 of the substrate W. During this transfer, the greater the amount of bending of the substrate W, the higher the position at which the underside of the substrate W will abut against the substrate holder (support pins).

[0100] When placing the substrate W on the substrate holder, it is desirable to lower the lowering speed to reduce the impact, but it is also desirable to lower the speed to improve throughput. Therefore, it is desirable to increase the lowering speed until the substrate W abuts on the substrate holder, and then set the lowering speed to a low value at the moment the substrate W abuts on the substrate holder.

[0101] Therefore, the control unit 140 determines the lowering speed when transferring the substrate W to the receiver PASS1 based on the amount of deflection of the substrate W on the hand 1. FIG. 13 is a flowchart showing an example of the operation of the substrate transport device TID. The example of FIG. 13 shows an example of the operation of transferring the substrate W to the receiver PASS1. The substrate W is placed on the hand 1. First, the rotation mechanism 33 rotates the hand 1 so that the hand 1 faces the receiver PASS1 (step S21). Next, the lifting mechanism 32 moves the height position of the hand 1 to a preset height position (step S22). Next, the advancing / retracting mechanism 31 moves the hand 1 forward and stops it at a position above the substrate holder of the receiver PASS1 (step S23). This position is set in advance, for example.

[0102] Next, the lifting mechanism 32 starts to lower the hand 1 (step S24). This increases the lowering speed of the hand 1 to a target value. Next, the control unit 140 sets a height reference value based on the amount of deflection of the substrate W on the hand 1 (step S25). This height reference value is set higher the greater the amount of deflection of the substrate W. The correspondence between the height reference value and the amount of deflection of the substrate W is set in advance, for example, by experiment or simulation. Correspondence information indicating this correspondence is stored in a storage medium of the control unit 140, for example, as a look-up table or a function. The control unit 140 sets the height reference value based on the amount of deflection of the substrate W and the correspondence information stored in the storage medium.

[0103] Next, the control unit 140 determines whether the current height position of the hand 1 is lower than the height reference value (step S26). Note that the height reference value may be set before this determination process, and may be set before the hand 1 is lowered (step S24).

[0104] The control unit 140 calculates the height position of the hand 1 based on, for example, the time elapsed since the start of descent of the hand 1 and the descent speed. The control unit 140 compares this height position with the height reference value, and if the height position is still equal to or greater than the height reference value, executes step S26 again.

[0105] When the height position of the hand 1 is less than the height reference value, the lifting mechanism 32 reduces the descent speed (step S27). This allows the lifting mechanism 32 to start reducing the descent speed from a higher position when the amount of bending of the substrate W is large. Therefore, the substrate W can be transferred to the substrate holder of the receiver PASS1 with the descent speed sufficiently reduced.

[0106] Furthermore, the hand 1 can be lowered at a high lowering speed until the height position of the hand 1 reaches the height reference value. Therefore, the substrates W can be transferred to the substrate holders of the receiver PASS1 with high throughput.

[0107] When the substrate W is placed on the substrate holder (support pins), the lifting mechanism 32 stops the descent of the empty hand 1, and the advancing / retracting mechanism 31 retracts the hand 1 from the receiver PASS1 (step S28).

[0108] As described above, when the amount of bending is large, the descent speed of the hand 1 can be reduced from a higher height position, and when the amount of bending is small, the descent speed of the hand 1 can be reduced from a lower height position. This allows the descent speed to be sufficiently reduced until the substrate W abuts on the substrate mounting portion, while still allowing the hand 1 to be lowered at a high descent speed up to that height position. Therefore, the substrate transport device TID can transfer the substrate W to the substrate holding portion of the mounting portion PASS1 with high throughput, while reducing the descent speed at the moment the substrate W is placed on the substrate holding portion.

[0109] Although the embodiments have been described above, various modifications to this substrate transport device are possible without departing from the spirit of the invention. Within the scope of the disclosure, the embodiments can be freely combined, or any component of each embodiment can be modified, or any component of each embodiment can be omitted.

[0110] For example, in the above-described specific example, the sensor 2 is provided on the base end side (rear end side) of the finger 11 of the hand 1. However, the sensor 2 may also be provided on the tip end side (front side) of the finger 11 of the hand 1. In short, the sensor 2 may be provided at a position facing the front end of the substrate W in the measurement direction D2 when the hand 1 is in an advanced state in which it has advanced into the substrate container C.

[0111] In the above-described specific example, the sensor 2 is provided on the finger 11 of the hand 1. However, this is not necessarily limited to this. For example, if another member is connected to the finger 11 and the connecting member 12, the sensor 2 may be connected to the other member.

[0112] Furthermore, in the above example, in order to determine the amount of deflection of the substrate W, the hand 1 is raised from a height position where the light from the light-emitting unit 21 is not blocked by the substrate W. However, this is not necessarily limited to this when it is not necessary to determine the amount of deflection of the substrate W. For example, the hand 1 may be advanced into the substrate container C at a height position where the light from the light-emitting unit 21 is blocked by the substrate W. In this case, with the hand 1 stopped at a stop position within the substrate container C, the sensor 2 can detect the position of the substrate W in the front-rear direction D1.

[0113] In the specific example described above, when the substrate transport device TID places the substrate W on the receiver PASS1, the lowering speed of the hand 1 is adjusted in accordance with the amount of bending of the substrate W. However, this adjustment of the lowering speed is not necessarily limited to placement on the receiver PASS1. For example, each processing unit of the processing section 120 is provided with a substrate holder for holding the substrate W. The substrate holder may include, for example, a plate-shaped substrate placement section having suction ports formed therein for suctioning the underside of the substrate W, and lift pins for raising and lowering the substrate W. The substrate placement section abuts the underside of the substrate W at least near the center of the substrate W. When the lift pins are raised, the lift pins support the substrate W above the substrate placement section. When the substrate W is loaded, the main transport mechanism T1 or the main transport mechanism T2 places the substrate W on the lift pins with the lift pins raised. The lift pins lower the substrate W while supporting it, and place it on the substrate placement section. In this case, the lowering speed of the lift pins may be adjusted according to the amount of bending of the substrate W. The correspondence between the amount of bending of the substrate W on the lift pins and the amount of bending of the substrate W on the hand 1 can also be set in advance by simulation, experiment, or the like. The greater the amount of bending of the substrate W, the lowering speed of the lift pins starts to decrease from a higher position. This allows the substrate W to be transferred to the substrate platform with high throughput, while also reducing the lowering speed at the time the substrate W is transferred to the substrate platform. [Explanation of symbols]

[0114] C Substrate container 1 hand 2. Detection unit (sensor) 21 Light-emitting part 22 Light receiving part 31 Advancement / retraction mechanism 32 Lifting mechanism 33 Moving mechanism (rotating mechanism) 13a Suction port 140 Control Unit 141 Arithmetic section

Claims

1. A substrate transport device that removes a substrate from a substrate container having an internal structure in which a plurality of substrates are stored in a horizontal position and stacked at intervals in the vertical direction, and transports the substrate to a substrate holding section, Hand and an advancing / retracting mechanism for moving the hand in a forward / backward direction to advance the hand into and retreat from the substrate container; a lifting mechanism that raises the hand and lifts the substrate from below with the hand; a moving mechanism that moves the hand to a position facing the substrate container; a detection unit that moves integrally with the hand, that is provided at a position adjacent to the substrate in a measurement direction that intersects with the front-rear direction when the advancing / retracting mechanism has advanced the hand into the substrate container, and that detects the position of the substrate in the front-rear direction when the advancing / retracting mechanism has advanced the hand into the substrate container; Equipped with The detection unit a light-emitting unit and a light-receiving unit arranged opposite each other in the measurement direction; Calculation unit and Including, The hand Finger and a protrusion provided on the finger and supporting the lower surface of the substrate; Including, the light emitting portion is provided so that a light emitting surface is located above an upper surface of the protrusion, the light receiving portion is provided so that a light receiving surface is located above an upper surface of the protrusion, the light-emitting unit irradiates a strip-shaped light having a width direction in the front-rear direction toward the light-receiving unit, The calculation unit determines the front-to-rear position of the substrate based on the amount of light received by the light receiving unit, and determines the amount of position adjustment to move the substrate based on the position.

2. A substrate transport device that removes a substrate from a substrate container having an internal structure in which a plurality of substrates are stored in a horizontal position and stacked at intervals in the vertical direction, and transports the substrate to a substrate holding section, Hand and an advancing / retracting mechanism for moving the hand in a forward / backward direction to advance the hand into and retreat from the substrate container; a lifting mechanism that raises the hand and lifts the substrate from below with the hand; a moving mechanism that moves the hand to a position facing the substrate container; a detection unit that moves integrally with the hand, that is provided at a position adjacent to the substrate in a measurement direction that intersects with the front-rear direction when the advancing / retracting mechanism has advanced the hand into the substrate container, and that detects the position of the substrate in the front-rear direction when the advancing / retracting mechanism has advanced the hand into the substrate container; Equipped with The detection unit a light-emitting unit and a light-receiving unit arranged opposite each other in the measurement direction; Calculation unit and Including, the light-emitting unit irradiates a strip-shaped light having a width direction in the front-rear direction toward the light-receiving unit, The calculation unit calculates the ratio between the amount of light received by the light receiving unit when the light from the light emitting unit is not blocked by the substrate and the amount of light received by the light receiving unit in the entering state, determines the front-to-rear position of the substrate based on the ratio, and determines whether the position is within an acceptable range.

3. 3. The substrate transport device according to claim 1, The substrate transport device, wherein the light emitting unit is provided at a different height from the light receiving unit.

4. 4. The substrate transport device according to claim 1, The substrate has a central portion and a peripheral portion that is outer than the central portion, and the peripheral portion is thicker than the central portion.

5. 5. The substrate transport device according to claim 1, The substrate transport device, wherein the hand has at least two suction ports formed therein.

Images