Substrate transport device and substrate processing device

Abstract

To provide a substrate transport device that detects the shape of a substrate and prevents inconvenience caused by the shape of the substrate.SOLUTION: A substrate transport device includes a sensor holding member 21 having a first sensor 41 and a second sensor 42 in addition to an acquisition hand 11a that transports a substrate W. When a first substrate in a carrier is to be transported, according to the present invention, the sensor holding member 21 first enters between a first substrate and a second substrate. Then, the distance between the first substrate and the second substrate is measured. When the acquisition hand 11a is caused to enter between the first substrate and the second substrate, the entry height of the acquisition hand 11a is adjusted such that the clearance between the acquisition hand 11a and the first substrate and the clearance between the acquisition hand 11a and the second substrate are both equal to or greater than a predetermined value.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a substrate transport device and a substrate processing device for transporting various substrates such as semiconductor substrates, substrates for FPDs (Flat Panel Displays) such as liquid crystal displays and organic EL (Electroluminescence) display devices, glass substrates for photomasks, and substrates for optical disks. [Background technology]

[0002] The substrate processing apparatus described in Patent Document 1 includes a mounting table for mounting a carrier capable of storing substrates in a stacked manner with gaps therebetween, and a substrate transport apparatus for transporting substrates from the carrier. The substrate processing apparatus in Patent Document 1 includes a mapping sensor for checking how substrates are stacked in the carrier. The mapping sensor generates mapping data that is referenced when substrates are transported from the carrier. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-72384 A Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional substrate transport devices can only know the distribution of substrates in a carrier, i.e., which part of the carrier the substrate is inserted in, but cannot know the shape of the substrate, specifically, the width of the gap between the upper and lower substrates caused by the thickness and warping of the substrate. If the substrate shape is not taken into consideration when transporting the substrate, problems such as the substrate transport hand coming into contact with the substrate will occur.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a substrate transport device that is capable of detecting the shape of a substrate and preventing inconveniences caused by the shape of the substrate. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention has the following configuration. That is, the present invention is a substrate transport device, which includes a hand that stores a plurality of substrates in a horizontal position with a predetermined interval between them in a vertical direction from a carrier having an opening on one side for removing and storing substrates, and that holds and transports the substrates one by one by entering between adjacent substrates vertically; a sensor holding member which is a member that enters between vertically adjacent substrates and includes a first sensor that measures the distance to the upper substrate and a second sensor that measures the distance to the lower substrate; a control unit that controls the hand and the sensor holding member to move forward and backward between the opening of the carrier and adjacent substrates vertically; The control unit is by inserting the sensor holding member between a first substrate to be transported and a second substrate located below the first substrate, a minimum distance between the substrates is measured from a sum of a first minimum distance of the substrate at a first measurement position where the first sensor is closest to the first substrate and a second minimum distance of the substrate at a second measurement position where the second sensor is closest to the second substrate; When the hand is inserted between the first substrate and the second substrate, the hand insertion height is adjusted according to the minimum distance between the substrates so that both the distance from the hand to the first substrate and the distance from the hand to the second substrate are equal to or greater than a predetermined value. It is characterized by:

[0007] [Actions and Effects] The above-mentioned substrate transport device is provided with a sensor holding member having a first sensor and a second sensor in addition to the hand that transports the substrate. When the first substrate in the carrier is to be transported, according to the present invention, the sensor holding member first enters between the first substrate and the second substrate. Then, the distance between the first substrate and the second substrate is measured. Since the substrate placement position is determined in the carrier, the distance between the first substrate and the second substrate should be constant. However, in reality, the first substrate and the second substrate are not necessarily flat. Therefore, when the distance between the first substrate and the second substrate is actually measured, the minimum distance between the substrates is larger or smaller than expected. At the same time, the midpoint between the substrates is higher or lower than expected.

[0008] According to the present invention, when the hand is inserted between the first substrate and the second substrate, the insertion height of the hand is adjusted so that the clearance between the hand and the first substrate and the clearance between the hand and the second substrate are both equal to or greater than a predetermined value. With this configuration, the hand does not come into contact with any part of the first substrate other than the edge thereof due to the hand being too close to the first substrate. Similarly, the hand does not come into contact with any part of the second substrate other than the edge thereof due to the hand being too close to the second substrate.

[0009] In the above-mentioned substrate transport device, a guide member at a tip end of the hand for contacting an edge of the substrate; The first sensor and the second sensor are provided at a tip end of the sensor holding member, It is preferable that the thickness of the sensor holding member in the height direction at the tip end be smaller than the thickness of the hand in the height direction at the tip end.

[0010] [Functions and Effects] In the above-mentioned configuration, the thickness of the first and second sensors at the tip of the sensor holding member is smaller than the thickness of the guide member at the tip of the hand. With this configuration, the sensor holding member can enter between boards that the hand cannot enter, and the minimum distance between boards can be reliably measured.

[0011] In the above-mentioned substrate transport device, the first sensor measures a distance while being moved from an end of the first substrate located at an opening of the carrier to a depth of the carrier; the second sensor measures a distance while being moved from an end of the second substrate located at an opening of the carrier to a depth of the carrier; It is preferable that the control unit adjusts the entry height of the hand so that at a first measurement position where the first substrate and the first sensor are closest, and at a second measurement position where the second substrate and the second sensor are closest, the distance from the hand to the first substrate and the distance from the hand to the second substrate are both greater than or equal to a predetermined value.

[0012] [Functions and Effects] In the above-mentioned configuration, the hand's entry height is adjusted so that the clearance between the hand and the first substrate and the clearance between the hand and the second substrate are both equal to or greater than a predetermined value when the first substrate and the second substrate are closest to each other. With this configuration, the hand will not come into contact with the substrate when the first substrate and the second substrate are closest to each other.

[0013] In the above-mentioned substrate transport device, It is preferable that the control unit adjusts the entry height of the hand so that the distance from the hand to the first substrate at the first measurement position and the distance from the hand to the second substrate at the second measurement position are the same.

[0014] [Function and Effect] In the above-mentioned configuration, the hand's entry height is adjusted so that the clearance between the hand and the first substrate and the clearance between the hand and the second substrate are the same. With this configuration, a sufficient distance can be secured not only between the hand and the first substrate but also between the hand and the second substrate to transport the substrate, so that the hand can transport the substrate more reliably.

[0015] In the above-mentioned substrate transport device, It is preferable that the sensor holding member does not transport a substrate.

[0016] [Functions and Effects] In the above-mentioned configuration, the sensor holding member does not transport the substrate. With this configuration, there is no need to provide the sensor holding member with a guide member for holding the substrate, and the sensor holding member can easily enter between the substrates.

[0017] In the above-mentioned substrate transport device, If the distance between the first substrate and the second substrate is short and the distance from the hand to the first substrate at the first measurement position and the distance from the hand to the second substrate at the second measurement position cannot be simultaneously made greater than or equal to a predetermined value, it is preferable not to insert the hand between the first substrate and the second substrate.

[0018] [Functions and Effects] In the above-mentioned configuration, if the distance between the first and second substrates is short and the clearance between the hand and the first substrate and the clearance between the hand and the second substrate cannot be made equal to or greater than a predetermined value at the same time, it is determined that the first substrate cannot be transported, and the hand does not enter between the first and second substrates. With this configuration, it is possible to more reliably prevent the substrate from coming into contact with the hand except for the edge.

[0019] In the above-mentioned substrate transport device, an upper surface of the sensor holding member is located above a lower end of the first sensor; It is preferable that a lower surface of the sensor holding member is located lower than an upper end of the second sensor.

[0020] [Functions and Effects] In the above-mentioned configuration, the protrusion amount of the first sensor and the second sensor can be reduced by the thickness of the sensor holding member. Therefore, the height of the sensor holding member can be minimized, reducing the possibility that the sensor holding member will not be able to enter between the substrates.

[0021] In the above-mentioned substrate transport device, the hand includes a first holder that holds one end of the substrate and a second holder that holds the other end of the substrate; the sensor holding member includes at least two sensor groups each including the first sensor and the second sensor; a first sensor group measures a distance between the first substrate and the second substrate at an approach position of the first holder; A second sensor group measures the distance between the first substrate and the second substrate at the approach position of the second holder. A substrate transport device comprising:

[0022] [Functions and Effects] In the above-mentioned configuration, the sensor holding member is provided with a first sensor group that measures the minimum distance between the substrates at the position of the first holder held by the hand, and the sensor holding member is provided with a second sensor group that measures the minimum distance between the substrates at the position of the second holder held by the hand. In this way, it is possible to more reliably configure the hand so that it does not come into contact with any part other than the edges of the substrates.

[0023] In the above-mentioned substrate transport device, The sensor holding member includes a first protrusion extending to correspond to the first holding body and a second protrusion extending to correspond to the second holding body. A substrate transport device comprising:

[0024] [Functions and Effects] In the above-mentioned configuration, the sensor holding member includes a first protrusion extending in a first direction corresponding to the first holder, and a second protrusion extending in the first direction corresponding to the second holder. By making the shape of the sensor holding member resemble a hand in this way, information on the distance required for transportation can be obtained more reliably.

[0025] In the above-mentioned substrate transport device, It is preferable that the sensor holding member has the sensor group at a tip of the first protrusion and has the sensor group at a tip of the second protrusion.

[0026] [Functions and Effects] In the above-mentioned configuration, the sensor holding member has a sensor group at the tip of the first protrusion, and a sensor group at the tip of the second protrusion. With this configuration, the minimum distance between the substrates at the back of the carrier can be measured by slightly moving the sensor holding member.

[0027] In the above-mentioned substrate transport device, The sensor holding member is The first sensor and the second sensor are provided at the same position of the first protrusion, It is preferable that the first sensor and the second sensor are provided at the same position on the second protrusion.

[0028] [Functions and Effects] In the above-mentioned configuration, the sensor holding member has the first sensor and the second sensor at the same position in the first direction on the first protrusion. Also, the sensor holding member has the first sensor and the second sensor at the same position on the second protrusion. With this configuration, the upper substrate (first substrate) of the sensor holding member and the lower substrate (second substrate) of the sensor holding member can be measured under the same conditions, so that the minimum distance between the substrates can be calculated more accurately.

[0029] In the above-mentioned substrate transport device, It is preferable that the control unit does not allow the hand to enter between the first substrate and the second substrate when the distance between the first substrate and the second substrate is short and the sensor holding member cannot enter between the first substrate and the second substrate.

[0030] [Functions and Effects] In the above-mentioned configuration, if the distance between the first and second substrates is short and the sensor holding member cannot enter between the first and second substrates, it is determined that the first substrate cannot be transported, and the hand is not allowed to enter between the first and second substrates. With this configuration, it is possible to more reliably prevent the hand from coming into contact with parts of the substrate other than the edges.

[0031] In the above-mentioned substrate transport device, It is preferable that, when the first substrate remains on the carrier after the second substrate has been transported from the carrier, the control unit causes the hand to transport the first substrate.

[0032] [Function and Effect] In the above-mentioned configuration, if the first substrate that was previously determined to be untransportable remains in the carrier after the second substrate has been transported from the carrier, the first substrate is transported to the hand. With this configuration, the first substrate will not end up remaining in the carrier.

[0033] In the above-mentioned substrate transport device, The control unit is The sensor holding member is inserted between the first substrate and the second substrate at a first speed; It is preferable that the hand is advanced between the first substrate and the second substrate at a second speed that is faster than the first speed.

[0034] [Functions and Effects] In the above-mentioned configuration, the sensor holding member moves between the substrates at a speed faster than the hand, so that the substrate transport process can be speeded up.

[0035] In the above-mentioned substrate transport device, It is preferable that the sensor holding member is in the same position as the hand before entering between the substrates.

[0036] [Functions and Effects] In the above-mentioned configuration, the sensor holding member is in the same position as the hand before entering between the substrates. With this configuration, the present invention can be realized by using a single robot to selectively use the hand and the sensor holding member.

[0037] In the above-mentioned substrate transport device, The hand also serves as the sensor holding member, It is preferable that the first sensor and the second sensor are attached to the hand.

[0038] [Functions and Effects] In the above-mentioned configuration, the sensor group is provided at the tip of the hand body, closer to the guide member. With this configuration, it is possible to provide a substrate transport device with a simple configuration by omitting the sensor holding member.

[0039] In addition to the above-mentioned invention, this specification also discloses the following invention.

[0040] That is, the present invention is a substrate transport device, a first hand for high-speed transport that transports the substrates one by one from a carrier that stores a plurality of substrates in a horizontal position at a predetermined interval in a vertical direction; a second hand for low-speed transport that transports the substrates one by one from a carrier that stores a plurality of substrates in a horizontal position at a predetermined interval in a vertical direction; a control unit that controls the first hand or the second hand to move toward or away from a substrate in a first direction; A substrate transport device comprising:

[0041] [Actions and Effects] The above-mentioned substrate transport device has two types of hands, a first hand for high-speed transport and a second hand for low-speed transport, and is equipped with a control unit that transports substrates by selectively using the first hand and the second hand. With this configuration, if the shape of the substrate is nearly flat, the first hand can be used to transport the substrate at high speed, and if the substrate is significantly warped, the second hand can be used to transport the substrate at low speed. In other words, the substrate transport device according to the present invention can transport substrates in a manner that is more suited to the actual conditions of the substrates stored in the carrier.

[0042] In the above-mentioned substrate transport device, a first guide member that is provided at a tip end of the first hand and that abuts against an end of the substrate; a second guide member at a tip end of the second hand for contacting an end of the substrate; The thickness of the tip of the second hand in the height direction is smaller than the thickness of the tip of the first hand in the height direction. A substrate transport device comprising:

[0043] [Functions and Effects] According to the above-mentioned configuration, the thickness of the tip of the second hand in the height direction is smaller than the thickness of the tip of the first hand in the height direction. With this configuration, even if the substrate is significantly warped and the minimum distance between the substrates is short, the substrate to be transported can be transported more reliably by using the second hand.

[0044] In the above-mentioned substrate transport device, the first hand includes a first holder extending in a first direction and holding one end of the substrate, and a second holder extending in the first direction and holding the other end of the substrate, the second hand includes a first blade extending in the first direction and holding one end of the substrate, and a second blade extending in the first direction and holding the other end of the substrate, A space between the first holder and the second holder is smaller than a space between the first blade and the second blade. A substrate transport device comprising:

[0045] [Functions and Effects] According to the above-mentioned configuration, the space between the first holder and the second holder in the first hand is smaller than the space between the first blade and the second blade in the second hand. With this configuration, the first hand can hold the substrate more reliably, so that the substrate can be transported at high speed. Meanwhile, the second hand can reliably hold the warped substrate between the first blade and the second blade.

[0046] In the above-mentioned substrate transport device, the first hand has a pusher that grips a substrate; The second hand does not have the pusher. A substrate transport device comprising:

[0047] [Actions and Effects] According to the above-mentioned configuration, the first hand has a pusher that grips the substrate. This allows the first hand to securely grip the substrate and transport it at high speed. Furthermore, the second hand does not have a pusher. This simplifies the device configuration and reduces the thickness of the second hand in the height direction. Effect of the Invention

[0048] The substrate transport device of the present invention does not cause any inconvenience due to the shape of the substrate. [Brief description of the drawings]

[0049] [Figure 1] FIG. 1 is a plan view illustrating an overall configuration of a substrate processing apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a front view illustrating a configuration of a carrier according to the first embodiment. [Diagram 3] FIG. 2 is a schematic diagram illustrating a configuration of an indexer robot according to the first embodiment. [Figure 4] 2A to 2C are schematic diagrams illustrating a sensor holding member and a hand according to the first embodiment. [Diagram 5] FIG. 2 is a plan view illustrating a taking hand and a returning hand according to the first embodiment. [Figure 6] FIG. 2 is a plan view illustrating a sensor holding member according to the first embodiment. [Figure 7] 5A to 5C are schematic diagrams illustrating the operation of the indexer robot according to the first embodiment. [Figure 8] 5A to 5C are schematic diagrams illustrating the operation of the indexer robot according to the first embodiment. [Figure 9] 5A to 5C are schematic diagrams illustrating the operation of the indexer robot according to the first embodiment. [Figure 10] 5A to 5C are schematic diagrams illustrating the operation of the indexer robot according to the first embodiment. [Figure 11] 5A to 5C are schematic diagrams illustrating the operation of the indexer robot according to the first embodiment. [Figure 12] 4 is a flowchart illustrating an operation of the substrate processing apparatus according to the first embodiment. [Figure 13] FIG. 4 is a plan view for explaining the operation of the substrate processing apparatus in accordance with the first embodiment. [Figure 14] FIG. 11 is a schematic diagram illustrating a configuration of an indexer robot according to a second embodiment. [Figure 15] 10A and 10B are schematic diagrams illustrating a sensor holding member and a hand according to a second embodiment. [Figure 16] FIG. 11 is a plan view illustrating a first obtaining hand and a first returning hand according to the second embodiment. [Figure 17] FIG. 11 is a plan view illustrating a second obtaining hand and a second returning hand according to the second embodiment. [Figure 18] 10 is a flowchart illustrating the operation of the substrate processing apparatus according to the second embodiment. [Figure 19] FIG. 13 is a schematic diagram illustrating a configuration according to one modified example of the present invention. [Figure 20] FIG. 13 is a schematic diagram illustrating a configuration according to one modified example of the present invention. [Figure 21] FIG. 13 is a schematic diagram illustrating a configuration according to one modified example of the present invention. [Figure 22] FIG. 13 is a schematic diagram illustrating a configuration according to one modified example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0050] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following embodiment is a substrate processing apparatus equipped with a substrate transport apparatus of the present invention. The substrate transport apparatus of the present invention corresponds to an indexer block in the substrate processing apparatus of the embodiment. The indexer block has an indexer robot equipped with a hand for transporting substrates and a sensor holding member for measuring the distance between substrates. EXAMPLES

[0051] 1. Overall structure 1, the substrate processing apparatus 1 of this example has a load port 10, an indexer block 3, and a processing block 5. The substrate processing apparatus 1 of this example is for single-wafer substrate processing, and is configured to retrieve horizontally oriented substrates W one by one from a carrier C, process the substrates, and then return the substrates W one by one to the carrier.

[0052] In this specification, for convenience, the direction in which the indexer block 3 and the processing block 5 in the substrate processing apparatus 1 are arranged is called the "front-rear direction X". The front-rear direction X extends horizontally. In the front-rear direction X, the direction from the processing block 5 to the indexer block 3 in the substrate processing apparatus 1 is called the "front". The direction opposite to the front is called the "rear". The direction extending horizontally perpendicular to the front-rear direction X is called the "width direction Y". One direction of the "width direction Y" is called the "right" for convenience, and the other direction is called the "left" for convenience. The direction (height direction) perpendicular to the front-rear direction X and the width direction Y is called the "vertical direction Z" for convenience. In each figure, for reference, front, back, right, left, top, and bottom are appropriately indicated.

[0053] The load port 10 is a carrier mounting shelf on which the carriers C are mounted. A plurality of load ports 10 are arranged in the width direction Y, and each of the load ports 10 can mount one carrier C thereon.

[0054] The carrier C stores a plurality of substrates W in a horizontal position at a predetermined interval in the vertical direction Z. The carrier C also has an opening on one side for removing and storing substrates. A plurality of substrates W (e.g., 25 substrates) are stored in a single carrier C in a stacked manner at a certain interval in a horizontal position. FIG. 2 is a cross-sectional view for explaining the configuration of the carrier C. The carrier C has comb-shaped members 7 having a plurality of protrusions for placing the substrates W on both ends of the carrier housing. The protrusions of the comb-shaped members 7 are configured to place the ends of the substrates W on the comb-shaped members 7. The protrusions extend in the front-rear direction X. The protrusions are arranged at intervals of 1 cm. An example of the carrier C is a closed FOUP (Front Opening Unify Pod). In the present invention, an open container may be used as the carrier C.

[0055] The indexer block 3 corresponds to the substrate transport device of the present invention. The indexer block 3 is a rectangle extending in the width direction Y. The indexer block 3 is provided with an indexer robot IR. The indexer robot IR is capable of moving horizontally in the width direction Y. The indexer robot IR has a hand capable of holding and transporting a substrate W. The hand is a multi-joint arm configured to be capable of rotating, ascending, descending, and advancing / descending. The indexer robot IR can access the carrier C on the load port 10 and the path 24 provided in front of the processing block 5. The indexer robot IR can perform two operations: an operation of acquiring substrates W in a horizontal position one by one from the carrier C and placing them on the path 24, and an operation of acquiring substrates W in a horizontal position placed on the path 24 one by one and returning them to the carrier C. The unprocessed substrates W held in the carrier C are transported to the path 24 by the indexer robot IR. The processed substrate W is then placed on the path 24 and returned to the carrier C by the indexer robot IR.

[0056] The processing block 5 corresponds to a processing section of the present invention. The processing block 5 is configured to perform a predetermined processing on the substrate W. In the processing block 5, a plurality of single wafer processing chambers 5a are arranged. That is, three single wafer processing chambers 5a are arranged in each of the middle layer area, the upper layer area, and the lower layer area to form a stack. Two stacks are arranged in front and rear on the right side of the processing block 5. Similarly, two stacks are arranged in front and rear on the left side of the processing block 5. Therefore, twelve single wafer processing chambers 5a are mounted on the processing block 5. A substrate transport area extending in the front and rear direction X is provided in the center of the processing block 5. The center robot CR can move back and forth in the substrate transport area, and can obtain the substrates W in a horizontal position one by one from the path 24 and transport them to one of the single wafer processing chambers 5a. The center robot CR can obtain the substrates W in a horizontal position held by the single wafer processing chamber 5a one by one and return them to the path 24. In this way, the center robot CR can access each of the single wafer processing chambers 5a and the path 24.

[0057] The substrate processing performed by the single wafer processing chamber 5a includes, for example, a substrate cleaning process. The substrate processing apparatus 1 of this embodiment may be configured to perform various substrate processing operations using chemicals in addition to the substrate cleaning process.

[0058] 2. Configuring the Indexer Robot FIG. 3 is a schematic diagram showing the tip of the indexer robot IR with respect to substrate holding. The indexer robot IR includes an acquisition hand 11a, a return hand 11b, and a sensor holding member 21. The return hand 11b, the acquisition hand 11a, and the sensor holding member 21 are held by an arm 12 in a stacked state in the vertical direction Z. The arm 12 can move the return hand 11b, the acquisition hand 11a, and the sensor holding member 21 forward and backward individually in the front-rear direction X. Before entering between the substrates W, the sensor holding member 21 is set at the same height position as the acquisition hand 11a and the return hand 11b in the front-rear direction X. In the configuration of FIG. 3, the return hand 11b, the acquisition hand 11a, and the sensor holding member 21 are arranged from top to bottom in this order, but the order in which each member is arranged can be changed as appropriate.

[0059] The acquisition hand 11a corresponds to the hand of the present invention. The acquisition hand 11a holds unprocessed substrates W one by one from the carrier C by entering between the vertically adjacent substrates W and transports them to the path 24. The acquisition hand 11a has a hand body 31 and a guide member 32. The hand body 31 has a flat shape so that it can enter between the substrates. The guide member 32 is at the tip of the acquisition hand 11a and is configured to abut the end of the substrate W. That is, the guide member 32 is a tab provided at the tip of the hand body 31 and is a member that contacts the substrate W. The guide member 32 is provided on the upper surface of the hand body 31. Therefore, the guide member 32 is configured to hold the upper substrate W from below. The guide member 32 has a thick portion and a thin portion. Therefore, the guide member 32 has a thickness that differs in parts in the height direction. The wall portion of the thick portion of the guide member 32 facing the base end of the acquisition hand 11a can come into contact with the edge (bevel portion) of the substrate W. The flat portion facing upwards in the thin portion of the guide member 32 can come into contact with the peripheral portion of the underside of the substrate. A guide member is also provided at the base end of the hand body 31 (not shown in FIG. 3). The guide member constitutes a contact portion of the acquisition hand 11a that comes into contact with the substrate W.

[0060] The returning hand 11b has the same configuration as the above-mentioned acquiring hand 11a. That is, the returning hand 11b has a hand body 31 and a guide member 32. The returning hand 11b has the guide member 32 at the tip and base of the hand body 31 and the guide member 32 has a thick portion and a thin portion, which are the same as the acquiring hand 11a. The returning hand 11b in this example is provided to transport a clean substrate W that has been cleaned. By using different hands on the outward and return routes in the reciprocating motion of the substrate W, it becomes unnecessary to hold the substrate W after cleaning with the hand that holds the substrate W before cleaning. Therefore, by providing the returning hand 11b, the cleanliness of the substrate W after cleaning is maintained.

[0061] The sensor holding member 21 in FIG. 3 is a member that enters between the vertically adjacent substrates W. The sensor holding member 21 holds a first sensor 41 that measures the distance to the upper substrate W and a second sensor 42 that measures the distance to the lower substrate W. The sensor holding member 21 has a sensor group 43 consisting of the first sensor 41 and the second sensor 42. The sensor holding member 21 has a flat shape so that it can enter between the substrates. The first sensor 41 and the second sensor 42 are located at the tip of the sensor holding member 21. The sensor holding member 21 does not transport the substrate W. The sensor holding member 21 and the first sensor 41 and the second sensor 42 do not come into contact with the substrate W. The holding member main body 23 is a member that supports the first sensor 41 and the second sensor 42. The length by which the first sensor 41 protrudes from the holding member main body 23 is equal to the length by which the second sensor 42 protrudes from the holding member main body 23.

[0062] The second sensor 42 is provided below the first sensor 41. Therefore, the first sensor 41 and the second sensor 42 are stacked in the vertical direction Z to form a sensor group 43. The upper surface of the sensor holding member 21 is located above the lower end of the first sensor 41. That is, the first sensor 41 is partially buried in the sensor holding member 21. Similarly, the lower surface of the sensor holding member 21 is located below the upper end of the second sensor 42. That is, the second sensor 42 is partially buried in the sensor holding member 21. The sensor holding member 21 is provided with a through hole for fitting the sensor group 43, and the sensor group 43 is held by the sensor holding member 21 through the through hole. By configuring in this manner, the protrusion amount of the first sensor 41 and the second sensor 42 from the sensor holding member 21 can be minimized.

[0063] Specifically, the first sensor 41 and the second sensor 42 may be ultrasonic distance sensors (distance measuring sensors). The first sensor 41 emits ultrasonic waves upward from the sensor holding member 21, and the second sensor 42 emits ultrasonic waves downward from the sensor holding member 21. The first sensor 41 receives ultrasonic waves reflected by the upper substrate W and returning to the first sensor 41, and measures the distance from the sensor holding member 21 to the upper substrate W. The second sensor 42 receives ultrasonic waves reflected by the lower substrate W and returning to the second sensor 42, and measures the distance from the sensor holding member 21 to the lower substrate W. Therefore, based on the outputs of the first sensor 41 and the second sensor 42, the distance from the substrate W above the sensor holding member 21 to the substrate W below the sensor holding member 21 can be detected.

[0064] FIG. 4(a) shows the tip of the acquisition hand 11a and the return hand 11b, and FIG. 4(b) shows the tip of the sensor holding member 21. The thickness A1 in the vertical direction Z at the tip of the acquisition hand 11a and the return hand 11b is the distance from the upper end of the thick part of the guide member 32 to the lower end of the hand body 31. On the other hand, the thickness A2 in the vertical direction Z at the tip of the sensor holding member 21 is the distance from the upper end of the first sensor 41 to the lower end of the second sensor 42. In this way, the thickness in the height direction at the tip of the sensor holding member 21 is smaller than the thickness in the height direction at the tip of the acquisition hand 11a and the return hand 11b. The sensor holding member 21 is provided for the purpose of measuring whether the acquisition hand 11a and the return hand 11b can enter between the substrates. Therefore, the sensor holding member 21 may enter a gap in the substrate W into which the acquisition hand 11a and the return hand 11b cannot enter. By reducing the thickness of the sensor holding member 21, the sensor holding member 21 can enter a smaller gap. On the other hand, the thickness of the acquisition hand 11a is sufficiently large. Therefore, the acquisition hand 11a and the return hand 11b can transport the substrate W reliably.

[0065] 5 is a plan view illustrating the acquiring hand 11a and the returning hand 11b. The acquiring hand 11a and the returning hand 11b each include a base 36 and a first holder 33a and a second holder 33b formed by branching off the base 36. The first holder 33a is a member extending in the front-rear direction X and holding one end of the substrate W, and the second holder 33b is a member extending in the front-rear direction X and holding the other end of the substrate W. The guide member 32 is provided at the tip of the first holder 33a and the second holder 33b.

[0066] Guide members 34 are provided at the bases of the first holding body 33a and the second holding body 33b. Like the above-mentioned guide member 32, the guide member 34 has a thick portion constituting a wall portion with which the end (bevel portion) of the substrate W can come into contact, and a thin portion constituting a flat portion with which the peripheral portion of the lower portion of the substrate can come into contact. The thickness of the thick portion of the guide member 34 is the same as that of the thick portion of the guide member 32. The thickness of the thin portion of the guide member 34 is the same as that of the thin portion of the guide member 32. The walls of the guide members 32 and 34 are arranged to belong to an imaginary circle that is slightly larger than the substrate W. This allows the substrate W to fit into the receiving area for the substrate W that is constituted by the thin portions of the guide members 32 and 34.

[0067] The pusher 35 is provided at the tip of the base 36, and can push the substrate W held by the guide members 32 and 34 forward. The pusher 35 can move backward to an open state, and can move forward to a closed state. In order for the first holder 33a and the second holder 33b to hold the substrate W, first, the pusher 35 is placed in an open state so that the substrate W is held by the guide members 32 and 34. Then, the pusher 35 is placed in a closed state so that the substrate W is sandwiched between the guide members 32 and the pusher 35. In this manner, the substrate W is held.

[0068] 6 is a plan view illustrating the sensor holding member 21. The sensor holding member 21 has a first protruding portion 25a and a second protruding portion 25b that are formed by branching a base portion 26. The first protruding portion 25a and the second protruding portion 25b are members that extend in the front-rear direction X. The sensor holding member 21 has at least two sensor groups 43 each of which is composed of a first sensor 41 and a second sensor 42. That is, the first sensor group 43a is provided at the tip of the first protruding portion 25a. And the second sensor group 43b is provided at the tip of the second protruding portion 25b.

[0069] As can be seen by referring to FIG. 5 and FIG. 6, the sensor holding member 21 has a similar configuration to the acquisition hand 11a and the return hand 11b. That is, the sensor holding member 21 includes a first protrusion 25a extending in the front-rear direction X corresponding to the first holder 33a, and a second protrusion 25b extending in the front-rear direction corresponding to the second holder 33b. Therefore, the position of the first protrusion 25a of the sensor holding member 21 and the position of the first holder 33a of the acquisition hand 11a and the return hand 11b are at the same position in the width direction. The first sensor group 43a associated with the first protrusion 25a measures the distance between the substrate W to be transported at the entry position of the first holder 33a and the substrate W below. Similarly, the position of the second protrusion 25b of the sensor holding member 21 and the position of the second holder 33b of the acquisition hand 11a and the return hand 11b are at the same position in the width direction. The second sensor group 43b associated with the second protrusion 25b measures the distance between the substrate W to be transported at the entry position of the second holder 33b and the substrate W below.

[0070] 3 and 4, the first sensor 41 and the second sensor 42 are provided at the same position in the front-rear direction X on the first protrusion 25a in this example, and the first sensor 41 and the second sensor 42 are provided at the same position in the front-rear direction X on the second protrusion 25b. With this configuration, the distance from the substrate W to be transported to the sensor holding member 21 and the distance from the lower substrate W to the sensor holding member 21 can be measured at the same position in the front-rear direction X, so that the minimum distance between the substrates can be accurately measured.

[0071] 3. Indexer robot operation The operation of the indexer robot IR will be described. To transport the substrate W, first, as shown in Fig. 7(a), the indexer robot IR moves the arm 12 in the width direction Y, and first matches the position of the sensor holding member 21 in the width direction Y with the position of the substrate W. In this state, when the acquiring hand 11a is moved in the forward direction X, the acquiring hand 11a can approach the substrate W in the carrier C. In this example, the sensor holding member 21 is inserted between the substrates before the acquiring hand 11a is moved in the forward direction X, thereby measuring the minimum distance between the substrates.

[0072] Next, as shown in FIG. 7(b), the indexer robot IR moves the arm 12 in the vertical direction Z to position the sensor holding member 21 at an intermediate height between the first substrate W1 to be transported and the second substrate W2 below. This intermediate height position is a preset height position for each substrate W and is stored in a memory unit associated with the control unit 100 of the device. The first substrate W1 and the second substrate W2 in FIG. 7(b) are not warped and are flat. Therefore, the minimum distance between the substrates is the same regardless of the position in the front-rear direction X. The distance D1 is the ideal minimum distance between the substrates determined by the comb-shaped member 7 of the carrier C. Specifically, it is the length obtained by subtracting the thickness of the substrate W, which is determined by the standard, from the distance between the protrusions of the comb-shaped member 7. The distance between the protrusions of the comb-shaped member 7 is equal to the distance from the bottom surface of the first substrate W1 to the bottom surface of the second substrate W2. The distance required to transport the first substrate W1 using the acquisition hand 11a is the distance from the lower surface of the first substrate W1 to the upper surface of the second substrate W2. Therefore, the minimum distance between the substrates is shorter than the distance between the protrusions of the comb-shaped member 7 by the thickness of the second substrate W2. The position of the sensor holding member 21 in FIG. 7(b) is higher than the second substrate W2 by a distance d1, which is half the distance D1. Therefore, the sensor holding member 21 is lower than the first substrate W1 by the distance d1.

[0073] A specific position of the sensor holding member 21 in the vertical direction Z will be described. A reference position in the vertical direction Z is determined for the sensor holding member 21. The reference position is set at a position that is the midpoint between the upper end of a first sensor 41 (described later) and the lower end of a second sensor 42 (described later). Therefore, the distance from the upper end of the first sensor 41 to the reference position is equal to the distance from the reference position to the lower end of the second sensor 42.

[0074] After that, the indexer robot IR moves the sensor holding member 21 in the forward direction X to start measuring the minimum distance between the substrates. That is, the sensor holding member 21 enters between the first substrate W1 to be transported and the second substrate W2 located below the first substrate W1. Then, the sensor holding member 21 measures the minimum distance between the substrates from the sum of the first minimum distance Umim of the substrate W at the first measurement position s1 where the first sensor 41 is closest to the first substrate W1 and the second minimum distance Lmin of the substrate W at the second measurement position s2 where the second sensor 42 is closest to the second substrate W2. Specifically, the sensor holding member 21 continuously measures the minimum distance between the substrates at each position on a line extending in the forward and backward direction X while entering from the rear end to the front end of the first substrate W1 shown in FIG. 7(c). More specifically, the first sensor 41 recognizes that the distance from the first sensor 41 to the first substrate W1 is d2 by emitting a measurement wave from the upper surface of the first sensor 41. Similarly, the second sensor 42 measures the distance from the second sensor to the second substrate W2 by emitting a measurement wave from the lower surface of the second sensor 42. In FIG. 7(c), since the first substrate W1 and the second substrate W2 are flat, the distance to the first substrate W1 measured by the first sensor 41 is constant at d2 regardless of the position in the front-rear direction X. In addition, since the sensor holding member 21 is inserted between the first substrate W1 and the second substrate W2, the distance from the first substrate W1 to the first sensor 41 and the distance from the second substrate W2 to the second sensor 42 are equal. Therefore, the second sensor 42 recognizes that the distance from the second sensor 42 to the second substrate W2 is d2. The distance to the second substrate W2 measured by the second sensor 42 is constant at d2 regardless of the position in the front-rear direction X.

[0075] The minimum distance between the substrates can be calculated based on the data output by the first sensor 41 and the data output by the second sensor 42. That is, the minimum distance between the substrates is the sum of d2, which is the first minimum distance Umin from the first sensor 41 to the first substrate W1, d2, which is the second minimum distance Lmin from the second sensor 42 to the second substrate W2, and the thickness of the sensor group 43. In Fig. 7(c), the minimum distance between the substrates is calculated to be distance D1.

[0076] FIG. 8(a) is a plan view showing the sensor holding member 21 in the state of FIG. 7(c). According to this figure, the sensor group 43 measures the minimum distance between the substrates at the rear ends of the substrates W. FIG. 8(b) shows a state where the measurement of the minimum distance between the substrates at the front ends of the substrates W has been completed. At this time, the sensor group 43 is in a position protruding from the front end of the substrate W. FIG. 8(c) is a plan view showing the sensor holding member 21 in the state of FIG. 8(b). According to this figure, the sensor holding member 21 appears to overlap the substrate W. After that, the sensor holding member 21 is retreated, and this time the acquisition hand 11a enters between the first substrate W1 and the second substrate W2. Specifically, the indexer robot IR moves the arm 12 in the vertical direction Z to position the sensor holding member 21 at a height intermediate between the first substrate W1 to be transported and the second substrate W2 below.

[0077] The amount of movement of the arm 12 in the vertical direction Z at this time is determined based on the minimum distance between the substrates actually measured by the sensor holding member 21. That is, when the acquisition hand 11a is inserted between the first substrate W1 and the second substrate W2, the insertion height of the acquisition hand 11a is adjusted according to the minimum distance between the substrates so that the distance from the acquisition hand 11a to the first substrate W1 and the distance from the acquisition hand 11a to the second substrate W2 are both equal to or greater than a predetermined value. Specifically, the insertion height of the acquisition hand 11a is adjusted so that the distance from the acquisition hand 11a to the first substrate W1 and the distance from the acquisition hand 11a to the second substrate W2 are the same.

[0078] FIG. 9(a) shows a state when the entry height of the acquisition hand 11a is adjusted based on the actually measured minimum distance between the substrates. The actually measured minimum distance between the substrates is distance D1. The arm 12 adjusts the height of the acquisition hand 11a so that the distance from the lower surface of the acquisition hand 11a to the upper surface of the second substrate W2 is the same as the distance from the upper surface of the thick part of the guide member 32 of the acquisition hand 11a to the lower surface of the first substrate W1. When the minimum distance between the substrates is D1 as shown in FIG. 9(a), the reference position of the acquisition hand 11a may be located above the second substrate W2 by d1, which is half of the minimum distance D1 between the substrates. The height of the protrusion of the comb member 7 of the carrier C coincides with the lower end of the second substrate W2. The thickness of the second substrate W2 can be measured by referring to the distance measured by the second sensor 42. Therefore, the reference position of the acquisition hand 11a is aligned with a position d1, which is half the measured distance D1, above the position located above the upper end of the protrusion supporting the second substrate W2 by the thickness of the second substrate W2. The reference position of the acquisition hand 11a in the vertical direction Z is a middle position of the acquisition hand 11a having a predetermined thickness. The length from the reference position to the upper end of the thick part of the guide member 32 is equal to the length from the reference position to the lower end of the hand body 31. Therefore, the reference position corresponds to the midpoint between the upper end of the thick part of the guide member 32 and the lower end of the hand body 31.

[0079] The acquisition hand 11a positioned in the vertical direction Z is moved forward by the arm 12 and enters the intermediate position of the gap between the substrates. At this time, the distance from the first substrate W1 to the thick portion of the guide member 32 in the acquisition hand 11a is d3. The distance from the second substrate W2 to the lower end of the hand body 31 in the acquisition hand 11a is also d3. In this example, the reference position of the acquisition hand 11a is determined based on the thick portion of the guide member 32. This portion is the thickest portion in the acquisition hand 11a. According to this example, the guide member 32 located at the tip of the acquisition hand 11a is set so as not to collide with the substrate W in particular. The guide member 32 is the member of the acquisition hand 11a that is most likely to collide with the substrate W. According to this example, the guide member 32 is optimized so as not to collide with the substrate W.

[0080] When the front end of the acquiring hand 11a moves to the front end of the first substrate W1, the acquiring hand 11a rises by a predetermined amount and moves the first substrate W1 onto the comb-shaped member 7. At this time, the end (bevel portion) of the first substrate W1 faces the wall portion of the thick portion of the guide members 32 and 34. Thereafter, the pusher 35, which was in the open state, closes, and the first substrate W1 is gripped by the acquiring hand 11a. When the acquiring hand 11a moves backward in this state, the first substrate W1 is extracted from the carrier C accordingly. In this manner, the transport of the first substrate W1 is performed.

[0081] 4. Indexer robot operation (when the board is warped) Unlike FIG. 7(b), FIG. 9(b) shows a case where the first substrate W1 and the second substrate W2 to be transported are warped. In this example, such a first substrate W1 can also be transported suitably. To transport the first substrate W1, as in FIG. 7(b), the indexer robot IR first moves the arm 12 in the vertical direction Z as shown in FIG. 9(b) to position the sensor holding member 21 at an intermediate height between the first substrate W1 to be transported and the second substrate W2 below. The distance D1 is the ideal minimum distance between the substrates determined by the comb-shaped member 7 of the carrier C. Specifically, it is the length obtained by subtracting the thickness of the substrate W, which is determined by the standard, from the distance between the projections of the comb-shaped member 7. The position of the sensor holding member 21 in FIG. 9(b) is higher than the second substrate W2 by a distance d1, which is half the distance D1. Therefore, the sensor holding member 21 is lower than the first substrate W1 by the distance d1.

[0082] In this way, the position of the sensor holding member 21 is determined based on the ideal minimum distance between the substrates. Therefore, when the sensor holding member 21 measures the minimum distance between the substrates, the result is not necessarily the ideal value of distance D1. However, the minimum distance between the substrates at the substrate ends may be considered to be distance D1. This is because the peripheral portion of the substrate W is held by the comb-shaped member 7 of the carrier C. An example of the warping of the first substrate W1 at this time is a ball-shaped warping with a concave center of the substrate W. Also, an example of the warping of the second substrate W2 at this time is a ball-shaped warping similar to that of the first substrate W1. Due to this warping, the first substrate W1 and the second substrate W2 are rotating bodies, so that the heights of the left and right ends of the substrate W held by the comb-shaped member 7 are the same as the front and rear ends of the substrate W not held by the comb-shaped member 7. Therefore, in FIG. 9(b), the distance between the substrates at the substrate ends is illustrated as distance D1.

[0083] However, since the first substrate W1 is warped, the distance U from the first sensor 41 to the first substrate W1 varies depending on the position of the first substrate W1. FIG. 10(a) shows a state when the tip of the sensor holding member 21 has moved to the center of the first substrate W1. At this time, the first sensor 41 is closest to the first substrate W1. In other words, the distance between the first sensor 41 and the first substrate W1 becomes the first minimum distance Umin. The position of the first substrate W1 where the distance between the first sensor 41 and the first substrate W1 becomes the first minimum distance Umin is called the first measurement position s1.

[0084] Similarly, since the second substrate W2 is warped, the distance L from the second sensor 42 to the second substrate W2 varies depending on the position of the second substrate W2. FIG. 9(b) shows a state when the tip of the sensor holding member 21 is located at the tip of the first substrate W1. At this time, the second sensor 42 is closest to the second substrate W2. That is, the distance between the second sensor 42 and the second substrate W2 is the second minimum distance Lmin. The position of the second substrate W2 where the distance between the second sensor 42 and the second substrate W2 is the second minimum distance Umin is called the second measurement position s2.

[0085] The first sensor 41 in the sensor holding member 21 of this example measures the distance while being moved from the end of the first substrate W1 located at the opening of the carrier C to the back of the carrier C. Similarly, the second sensor 42 measures the distance while being moved from the end of the second substrate W2 located at the opening of the carrier C to the back of the carrier C. However, the first sensor 41 in this example measures the distance while being moved from the rear end to the front end of the first substrate W1. Similarly, the second sensor 42 measures the distance while being moved from the rear end to the front end of the second substrate W2. Then, the first sensor 41 and the second sensor 42 measure the minimum distance between the measurement substrates based on the distance between the substrates at the first measurement position s1 and the distance between the substrates at the second measurement position s2.

[0086] Here, the minimum distance D2 between the first substrate W1 and the second substrate W2 is the minimum distance in the height direction between the first substrate W1 and the second substrate W2 when the first substrate W1 and the second substrate W2 are viewed from the direction in which the sensor holding member 21 enters between the substrates (i.e., the direction from the rear end to the front end in the X direction). The height distance between the two substrates W1 and W2 is the distance between the lower end position (the part located at the lowest: the first measurement position s1) of the upper substrate W1 and the upper end position (the part located at the highest: the second measurement position s2) of the lower substrate W2. For example, when the upper and lower substrates W1 and W2 are warped as shown in FIG. 10(a), the part detected as the minimum distance d4 between the first sensor 41 and the first substrate W1 is the lower end position of the upper substrate W1. In FIG. 10(a), the center of the substrate W1 is the lower end position of the substrate W1. On the other hand, the part detected as the minimum distance d2 between the second sensor 42 and the second substrate W2 is the upper end position of the lower substrate W2. 10(a), the rear end of substrate W2 in the X direction is the upper end of substrate W2. The sum of minimum distance d4 and minimum distance d2 is the minimum distance D2 between substrates W1 and W2.

[0087] When the measurement of the gap between the substrates is completed, the sensor holding member 21 is moved backward, and the acquiring hand 11a now enters between the substrates. At this time, the entry height of the acquiring hand 11a is adjusted so that the distance from the acquiring hand 11a to the first substrate W1 and the distance from the acquiring hand 11a to the second substrate W2 are the same. To calculate the entry height of the acquiring hand 11a, the minimum distance D2 between the substrates is referenced.

[0088] When the acquisition hand 11a is inserted between the first substrate W1 and the second substrate W2, the acquisition hand 11a is most likely to collide with the first substrate W1 at the first measurement position s1. Also, when the acquisition hand 11a is inserted between the first substrate W1 and the second substrate W2, the acquisition hand 11a is most likely to collide with the second substrate W2 at the second measurement position s2. In the substrate transport device of this embodiment, the insertion height of the acquisition hand 11a is adjusted so that the substrate W is less likely to collide with the acquisition hand 11a at both the first measurement position s1 and the second measurement position s2.

[0089] FIG. 10(b) shows a state when the entry height of the acquisition hand 11a is adjusted based on the actually measured minimum distance between the substrates. The actually measured minimum distance between the substrates is D2. The arm 12 adjusts the height of the acquisition hand 11a so that the distance from the lower surface of the acquisition hand 11a to the upper surface of the second substrate W2 (generally speaking, the upper end portion of the second substrate W2) is the same as the distance from the upper surface of the thick part of the guide member 32 of the acquisition hand 11a to the lower surface of the first substrate W1 (generally speaking, the lower end portion of the first substrate W1). The arm 12 adjusts the height of the acquisition hand 11a so that the distance between the first substrate W1 and the acquisition hand 11a becomes d5 at the first measurement position s1 where the first substrate W1 and the acquisition hand 11a are closest to each other. Then, the arm 12 adjusts the height of the acquisition hand 11a so that the distance between the second substrate W2 and the acquisition hand 11a becomes d5 at the second measurement position s2 where the second substrate W2 and the acquisition hand 11a are closest to each other. That is, when the minimum distance between the substrates is D2 as shown in FIG. 10(b), the reference position of the acquisition hand 11a may be located upward from the second substrate W2 by d5, which is approximately half of the minimum distance D2 between the substrates. The height of the protrusion of the comb member 7 of the carrier C coincides with the lower end of the second substrate W2. The thickness of the second substrate W2 can be actually measured by referring to the distance measured by the second sensor 42. Therefore, the reference position of the acquisition hand 11a is aligned upward by d5, which is approximately half of the actually measured minimum distance D2, from the position located above the upper end of the protrusion supporting the second substrate W2 by the thickness of the second substrate W2. In this way, in this example, the entry height of the acquisition hand 11a is adjusted so that the distance from the acquisition hand 11a to the lower end position of the first substrate W1 is equal to or greater than a predetermined value at the first measurement position s1 where the lower end position of the first substrate W1 is closest to the first sensor 41. Similarly, the entry height of the acquisition hand 11a is adjusted so that the distance from the acquisition hand 11a to the upper end position of the second substrate W2 is equal to or greater than a predetermined value at the second measurement position s2 where the upper end position of the second substrate W2 is closest to the second sensor 42.

[0090] The acquisition hand 11a positioned in the vertical direction Z is moved forward by the arm 12 and enters the intermediate position of the gap between the substrates. At this time, the distance from the first substrate W1 to the thick portion of the guide member 32 in the acquisition hand 11a is d6. The distance from the second substrate W2 to the lower end of the hand body 31 in the acquisition hand 11a is d7, which is shorter than d6. As the tip of the acquisition hand 11a enters between the substrates, the first substrate W1 gradually approaches the tip of the acquisition hand 11a. Specifically, the distance from the tip of the acquisition hand 11a to the first substrate W1 decreases from d6 to d7, with d6 being the initial value. This is because the first substrate W1 has a shape warped toward the second substrate W2. On the other hand, even if the tip of the acquisition hand 11a enters between the substrates, the second substrate W2 does not approach the tip of the acquisition hand 11a. Therefore, the distance from the tip of the acquisition hand 11a to the second substrate W2 is not less than d7. Fig. 10(c) illustrates the state when the first substrate W1 is closest to the tip of the acquisition hand 11a. That is, the distance from the lower end of the first substrate W1 to the upper end of the thick part of the guide member 32 is d7, and the distance from the lower end of the hand body 31 to the upper end of the second substrate W2 is longer than d7. Since d7 is greater than or equal to the distance required for substrate transport, the acquisition hand 11a does not collide with the first substrate W1 or the second substrate W2 while entering between the substrates.

[0091] 10(c) and reaches the front end of the first substrate W1, the distance from the first substrate W1 to the tip of the obtaining hand 11a increases from d7. Therefore, even during this operation, the obtaining hand 11a does not collide with the first substrate W1 or the second substrate W2.

[0092] 5. Indexer robot operation (when the acquisition hand cannot enter) In this example, if the measurement of the minimum distance between the substrates shows that the distance between the first substrate W1 and the second substrate W2 is short and the distance from the acquisition hand 11a to the first substrate W1 at the first measurement position s1 and the distance from the acquisition hand to the second substrate W2 at the second measurement position s2 cannot be simultaneously made greater than or equal to a predetermined value, the acquisition hand 11a is configured not to enter between the first substrate W1 and the second substrate W2.

[0093] Fig. 11(a) illustrates a case where the minimum distance between the substrates is D3. The minimum value D3 is even shorter than the above-mentioned minimum distance D2, and the first substrate W1 is accordingly warped more than in Fig. 9(b). The operation of the indexer robot IR in this case will be described below.

[0094] First, the indexer robot IR moves the arm 12 in the vertical direction Z to position the sensor holding member 21 at a height midway between the first substrate W1 to be transported and the second substrate W2 underneath. The distance D1 is the ideal distance between the substrates determined by the comb-shaped member 7 of the carrier C. Specifically, it is the length obtained by subtracting the thickness of the substrate W, which is determined by standards, from the distance between the protrusions of the comb-shaped member 7. The position of the sensor holding member 21 is higher than the second substrate W2 by a distance d1, which is half the distance D1. Therefore, the sensor holding member 21 is lower than the first substrate W1 by a distance d8.

[0095] Since the first substrate W1 is warped, the minimum distance between the substrates varies depending on the position of the substrate W. FIG. 11(a) shows a state when the tip of the sensor holding member 21 moves to the center of the first substrate W1. At this time, the first sensor 41 is closest to the first substrate W1. That is, the distance between the first sensor 41 and the first substrate W1 is d8. On the other hand, since the second substrate W2 is flat, the distance between the second sensor 42 and the second substrate W2 is d2. The sensor holding member 21 measures the minimum value D3 of the distance between the first substrate W1 and the second substrate W2 based on d8 and d2. That is, the minimum value D3 is a value obtained by adding the thickness of the sensor group 43 in the vertical direction Z to d8 and d2. The portion where the substrates are closest to each other by the minimum value D3 is most likely to collide with the acquisition hand 11a during substrate transport.

[0096] The minimum value D3 is smaller than twice the predetermined value plus the thickness of the acquisition hand 11a, and the distance from the acquisition hand 11a to the first substrate W1 and the distance from the acquisition hand 11a to the second substrate W2 cannot be greater than or equal to the predetermined value at the same time. In this case, the indexer robot IR of this example does not allow the acquisition hand 11a to enter between the first substrate W1 and the second substrate W2. In this way, it is possible to prevent a collision between the first substrate W1 and the acquisition hand 11a during the transport of the first substrate W1.

[0097] 6. Indexer robot operation (when the sensor holder cannot enter) In this example, if the measurement of the minimum distance between the substrates shows that the distance between the first substrate W1 and the second substrate W2 is short and the sensor holding member 21 cannot be inserted between the first substrate W1 and the second substrate W2, the acquisition hand 11a is not inserted between the first substrate W1 and the second substrate W2.

[0098] Fig. 11(b) illustrates a case where the minimum distance between the substrates is D4. The minimum value D4 is even shorter than the minimum value D3 described above, and the first substrate W1 is accordingly warped more than in Fig. 11(a). The operation of the indexer robot IR in this case will be described below.

[0099] First, the indexer robot IR moves the arm 12 in the vertical direction Z to position the sensor holding member 21 at an intermediate height between the first substrate W1 to be transported and the second substrate W2 below. The distance D1 is the ideal minimum distance between the substrates determined by the comb-shaped member 7 of the carrier C. Specifically, it is the length obtained by subtracting the thickness of the substrate W, which is determined by standards, from the distance between the protrusions of the comb-shaped member 7. The position of the sensor holding member 21 is higher than the second substrate W2 by a distance d1, which is half the distance D1. Therefore, the sensor holding member 21 is lower than the first substrate W1 by the distance d1.

[0100] Since the first substrate W1 is warped, the minimum distance between the substrates varies depending on the position of the substrate W. FIG. 11(b) shows the state when the tip of the sensor holding member 21 moves to the center of the first substrate W1. At this time, the distance between the first sensor 41 and the first substrate W1 is d9 before the tip of the sensor holding member 21 approaches the first substrate W1. On the other hand, since the second substrate W2 is flat, the distance between the second sensor 42 and the second substrate W2 is d2. The substrate transport device of this example is configured to stop measuring the minimum distance between the substrates when the distance between the first sensor 41 and the first substrate W1 becomes d9 and to move the sensor holding member 21 back. Similarly, the substrate transport device of this example is configured to stop measuring the minimum distance between the substrates when the distance between the second sensor 42 and the second substrate W2 becomes d9 and to move the sensor holding member 21 back. By configuring in this way, the sensor holding member 21 and the substrate W do not collide with each other.

[0101] 11(b) shows an example in which the advancement of the sensor holding member 21 is stopped because the first substrate W1 and the first sensor 41 have come close to each other. Similarly, when the second substrate W2 is warped and the distance between the second substrate W2 and the second sensor 42 becomes d9, the advancement of the sensor holding member 21 is stopped.

[0102] If the sensor holding member 21 cannot enter between the first substrate W1 and the second substrate W2 due to the sensor holding member 21 turning back, the acquisition hand 11a is not allowed to enter between the first substrate W1 and the second substrate W2. In other words, when the distance d9 is detected by the first sensor 41 or the second sensor, it is determined that the acquisition hand 11a will not transport the first substrate W1. In this way, collision between the first substrate W1 and the acquisition hand 11a during transportation of the first substrate W1 can be prevented.

[0103] 7.Other configurations As can be seen by referring to Fig. 1, the substrate transport device of this example includes a control unit 100. The control unit 100 is configured, for example, by a CPU (Central Processing Unit). The specific configuration of the control unit 100 is not limited, and for example, the control unit 100 may be configured by a single processor, or the control unit 100 may be configured by individual processors.

[0104] The control related to the control unit 100 includes, for example, control related to the indexer robot IR. That is, the control unit 100 controls the forward and backward movement of the sensor holding member 21, the forward and backward movement of the acquiring hand 11a and the returning hand 11b, the opening and closing movement of the pusher 35, the movement of the arm 12 in the vertical direction Z, a mapping sensor described below, and a movement mechanism of the mapping sensor. In particular, the control unit 100 is configured to move the acquiring hand 11a, the returning hand 11b, and the sensor holding member 21 forward and backward relative to the substrate W.

[0105] Although not shown in FIG. 1, the substrate transport apparatus of this example includes a memory unit accessible by the control unit 100. The memory unit stores programs and parameters related to control. Furthermore, the memory unit stores the minimum distance between each substrate measured by the sensor member 21 described above. The memory unit may be configured as a single device, or may be configured as individual devices corresponding to each control unit. Additionally, the substrate transport apparatus of this example has no particular limitations on the configuration of the device that realizes the memory unit.

[0106] 8. Circuit board transport flow Fig. 12 is a flow chart illustrating the operation of the substrate transfer apparatus of the present invention. Hereinafter, the operation of the substrate transfer apparatus when a substrate cleaning process is performed by the substrate processing apparatus 1 of the present invention will be described. Fig. 13 shows the substrate W being transferred within the substrate processing apparatus 1. Fig. 13 will also be referred to as appropriate in the following description.

[0107] Step S1: When a carrier C to be processed is placed on the load port 10, the substrate transport device starts a mapping operation of the substrate W. The substrate transport device is equipped with a mapping sensor for performing this operation, and a movement mechanism for the mapping sensor. The movement mechanism can move the mapping sensor in the vertical direction Z. The mapping sensor is a non-contact sensor and can sense the presence or absence of the substrate W. Specifically, the mapping operation is performed by moving the mapping sensor in the vertical direction Z relative to the carrier C. This makes it possible to know which part of the comb member 7 of the carrier C the substrate W is placed on. The mapping operation is an operation for obtaining the distribution of the substrate W in the carrier C.

[0108] Step S2: The indexer robot IR is moved to the rear of the carrier C, and the sensor holding member 21 enters the carrier C. When the substrates W are supported by the comb-shaped member 7 at intervals of 1 cm, the sensor holding member 21 enters between these substrates W. 1 cm is the arrangement pitch of the protrusions on the comb-shaped member 7. When 25 substrates W are arranged at intervals of 1 cm on the carrier C, the sensor holding member 21 enters each of the 24 gaps between the substrates in order. The minimum distance between the substrates acquired by the sensor holding member 21 is stored in the storage unit. When the substrates W are supported on the carrier C at intervals of 2 cm or more, it can be said that the minimum distance between the substrates is sufficient for transportation without measurement, so the entry operation of the sensor holding member 21 can be omitted. How the substrates W are arranged on the carrier C can be known by referring to the result of the mapping operation.

[0109] Step S3: The height of the reference position of the acquiring hand 11a is determined based on the measurement result between the substrates by the sensor holding member 21. Then, the parameters related to the control of the acquiring hand 11a are changed so that the reference position of the acquiring hand 11a is set to the determined height. Specifically, this operation is realized by rewriting the hand height offset value that determines the height of the acquiring hand 11a.

[0110] Step S4: The arm 12 of the indexer robot IR moves vertically to position the acquiring hand 11a at the height of the substrate W to be transported. The height of the acquiring hand 11a at this time is a height suitable for transporting the substrate W to be transported. The acquiring hand 11a grips the substrate W to be transported and delivers it to the path 24 (see arrow a in FIG. 13).

[0111] Step S5: The unprocessed substrate W held on the path 24 is transported by the center robot CR to the single-wafer processing chamber 5a (see arrow b in FIG. 13). The single-wafer processing chamber 5a performs a cleaning process on the substrate W. The processed substrate W is transported by the center robot CR to the path 24 (see arrow c in FIG. 13).

[0112] Step S6: The clean substrate W after cleaning is transported by the returning hand 11b. First, the height of the reference position in the returning hand 11b is determined based on the measurement result between the substrates by the sensor holding member 21. That is, parameters related to the control of the returning hand 11b are changed so that the reference position of the returning hand 11b is at the determined height. Specifically, this operation is realized by rewriting the hand height offset value that determines the height of the returning hand 11b.

[0113] The hand height offset value for the acquiring hand 11a can be reused to rewrite the hand height offset value for the returning hand 11b. After the substrate processing, each of the substrates W held in the carrier C is returned to the carrier C while maintaining the order of arrangement. Therefore, the height of the returning hand 11b when returning the substrate W to the carrier C is the same as the height of the acquiring hand 11a when acquiring the substrate W from the carrier C. The height of the acquiring hand 11a is a unique value for each substrate W held in the carrier C. When returning the substrate W to the carrier C, the height of the acquiring hand 11a is reproduced by the returning hand 11b based on these unique values. In this way, the tip of the returning hand 11b does not collide with the substrate W when the substrate W is returned.

[0114] Step S7: The returning hand 11b acquires the substrate W to be transported from the path 24. The arm 12 of the indexer robot IR moves vertically to position the returning hand 11b at the height determined in step S6. The height of the returning hand 11b when the returning hand 11b finishes placing the substrate W on the carrier C and returns to the substrate transport device will be the same as that of the acquiring hand 11a when acquiring the substrate W from the carrier C. This is because the acquiring hand 11a and the returning hand 11b operate based on a common hand height offset value. The returning hand 11b transports the substrate W to be transported from the path 24 to the carrier C (see arrow d in FIG. 13). The substrate W held on a certain protrusion on the comb member 7 of the carrier C is returned to the same protrusion after the substrate acquiring operation and the substrate returning operation.

[0115] Step S8: When the substrate W has been returned to the carrier C, the mapping operation of the substrate W is performed again in the same manner as in step S1. This completes the operation of the substrate transport apparatus of this example.

[0116] Note that the above description of the operations from step S1 to step S8 focuses on one substrate W. Therefore, when multiple substrates W are transported from the carrier C to perform cleaning processing on the substrates W, steps S3 and S4 may be repeated before proceeding to step S5. Similarly, steps S6 and S7 may be repeated before proceeding to step S9.

[0117] 9. Effects of Example 1 As described above, the above-mentioned substrate transport device includes the sensor holding member 21 having the first sensor 41 and the second sensor 42 in addition to the acquisition hand 11a and the return hand 11b that transport the substrate W. When the first substrate W1 in the carrier C is to be transported, according to the present invention, the sensor holding member 21 first enters between the first substrate W1 and the second substrate W2. Then, the distance between the first substrate W1 and the second substrate W2 is measured. Since the placement position of the substrate W is determined on the carrier C, the distance between the first substrate W1 and the second substrate W2 should be constant. However, in reality, the first substrate W1 and the second substrate W2 are not necessarily flat. Therefore, when the distance between the first substrate W1 and the second substrate W2 is actually measured, the minimum distance between the substrates is larger or smaller than expected. At the same time, the intermediate position between the substrates is higher or lower than expected.

[0118] According to the present invention, when the acquiring hand 11a and the returning hand 11b are inserted between the first substrate W1 and the second substrate W2, the insertion height of the acquiring hand 11a and the returning hand 11b is adjusted so that the clearance between the acquiring hand 11a and the returning hand 11b and the first substrate W1 and the clearance between the acquiring hand 11a and the returning hand 11b and the second substrate W2 are both equal to or greater than a predetermined value. With this configuration, the acquiring hand 11a and the returning hand 11b do not come into contact with any part other than the edge of the first substrate W1 because the acquiring hand 11a and the returning hand 11b are too close to the first substrate W1. Similarly, the acquiring hand 11a and the returning hand 11b do not come into contact with any part other than the edge of the second substrate W2 because the acquiring hand 11a and the returning hand 11b are too close to the second substrate W2.

[0119] In the above-mentioned configuration, the thickness formed by the first sensor 41 and the second sensor 42 at the tip of the sensor holding member 21 is smaller than the thickness formed by the guide member 32 at the tips of the acquiring hand 11a and the returning hand 11b. With this configuration, the sensor holding member 21 can enter between the substrates where the acquiring hand 11a and the returning hand 11b cannot enter, and the minimum distance between the substrates can be reliably measured.

[0120] In the above-mentioned configuration, the entry heights of the acquiring hand 11a and the returning hand 11b are adjusted so that the clearances between the acquiring hand 11a, the returning hand 11b and the first substrate W1 and the clearances between the acquiring hand 11a, the returning hand 11b and the second substrate W2 are equal to or greater than a predetermined value when the first substrate W1 and the second substrate W2 are closest to each other. With this configuration, the acquiring hand 11a and the returning hand 11b do not come into contact with the substrate W when the first substrate W1 and the second substrate W2 are closest to each other.

[0121] In the above-mentioned configuration, the entry heights of the acquiring hand 11a and the returning hand 11b are adjusted so that the clearances between the acquiring hand 11a, the returning hand 11b and the first substrate W1 and the clearances between the acquiring hand 11a, the returning hand 11b and the second substrate W2 are the same. With this configuration, the substrate W can be transported while ensuring a sufficient distance not only between the acquiring hand 11a, the returning hand 11b and the first substrate W1 but also between the acquiring hand 11a, the returning hand 11b and the second substrate W2, so that the hands can transport the substrate W more reliably.

[0122] In the above-described configuration, the sensor holding member 21 does not transport the substrate W. With this configuration, it is not necessary to provide the guide member 32 for holding the substrate W on the sensor holding member 21, and the sensor holding member 21 can easily enter between the substrates.

[0123] In the above-mentioned configuration, if the distance between the first substrate W1 and the second substrate W2 is short and the clearance between the acquiring hand 11a, the returning hand 11b and the first substrate W1, and the clearance between the acquiring hand 11a, the returning hand 11b and the second substrate W2 cannot be made equal to or greater than a predetermined value at the same time, it is determined that the first substrate W1 cannot be transported, and the acquiring hand 11a and the returning hand 11b do not enter between the first substrate W1 and the second substrate W2. With this configuration, it is possible to more reliably prevent the acquiring hand 11a and the returning hand 11b from contacting the substrate W other than the edge portion.

[0124] In the above-described configuration, the protrusion amount of the first sensor 41 and the second sensor 42 can be reduced by the thickness of the sensor holding member 21. Therefore, the height of the sensor holding member 21 can be minimized, reducing the possibility that the sensor holding member 21 will not be able to enter between the substrates.

[0125] In the above-mentioned configuration, the first sensor group 43 that measures the minimum distance between the substrates at the position of the first holder 33a of the acquiring hand 11a and the returning hand 11b is provided on the sensor holding member 21, and the second sensor group 43 that measures the minimum distance between the substrates at the position of the second holder 33b of the acquiring hand 11a and the returning hand 11b is provided on the sensor holding member 21. In this manner, it is possible to more reliably configure the acquiring hand 11a and the returning hand 11b so as not to contact any part of the substrate W other than the edge thereof.

[0126] In the above-mentioned configuration, the sensor holding member 21 includes a first protrusion 25a extending in the front-rear direction X corresponding to the first holding body 33a, and a second protrusion 25b extending in the front-rear direction X corresponding to the second holding body 33b. By making the shape of the sensor holding member 21 similar to the acquiring hand 11a and the returning hand 11b in this way, information on the distance required for transport can be acquired more reliably.

[0127] In the above-described configuration, the sensor holding member 21 includes a sensor group 43 at the tip of the first protrusion 25a, and a sensor group 43 at the tip of the second protrusion 25b. With this configuration, the minimum distance between the substrates at the back of the carrier C can be measured by slightly moving the sensor holding member 21.

[0128] In the above-described configuration, the sensor holding member 21 includes the first sensor 41 and the second sensor 42 at the same position in the front-rear direction X on the first protrusion 25a. The sensor holding member 21 also includes the first sensor 41 and the second sensor 42 at the same position in the front-rear direction X on the second protrusion 25b. With this configuration, the upper substrate (first substrate W1) of the sensor holding member 21 and the lower substrate (second substrate W2) of the sensor holding member 21 can be measured under the same conditions, so that the minimum distance between the substrates can be calculated more accurately.

[0129] In the above-mentioned configuration, if the distance between the first substrate W1 and the second substrate W2 is short and the sensor holding member 21 cannot enter between the first substrate W1 and the second substrate W2, it is determined that the first substrate W1 cannot be transported, and the acquiring hand 11a and the returning hand 11b are not allowed to enter between the first substrate W1 and the second substrate W2. With this configuration, it is possible to more reliably prevent parts of the substrate W other than the edges from coming into contact with the acquiring hand 11a and the returning hand 11b.

[0130] In the above-described configuration, the sensor holding member 21 is in the same position as the acquiring hand 11a and the returning hand 11b in the front-rear direction X before entering between the substrates W. With this configuration, the present invention can be realized by having a single robot selectively use the acquiring hand 11a, the returning hand 11b, and the sensor holding member 21. EXAMPLES

[0131] 10. Overview of Example 2 The second embodiment relates to a substrate transport apparatus, and will be described by taking as an example a substrate processing apparatus 1 incorporating the substrate transport apparatus, as in the first embodiment. As described with reference to Fig. 1, the substrate processing apparatus 1 of the second embodiment has a load port 10, an indexer block 3, and a processing block 5. The substrate transport apparatus of this embodiment differs from that of the first embodiment in the configuration of the indexer robot IR in the indexer block 3.

[0132] 11. Configuring the Indexer Robot FIG. 14 is a schematic diagram showing the tip of the indexer robot IR for holding a substrate. The indexer robot IR includes a first acquisition hand 51a, a first return hand 51b, a second acquisition hand 61a, and a second return hand 61b. The first acquisition hand 51a, the first return hand 51b, the second acquisition hand 61a, and the second return hand 61b are held by the arm 13 in a stacked state in the vertical direction Z. The arm 13 can move the first acquisition hand 51a, the first return hand 51b, the second acquisition hand 61a, and the second return hand 61b individually forward and backward in the forward and backward directions X. In the configuration of FIG. 14, the second return hand 61b, the second acquisition hand 61a, the first return hand 51b, and the first acquisition hand 51a are arranged from top to bottom in this order, but the order in which the members are arranged can be changed as appropriate.

[0133] The first acquisition hand 51a corresponds to the first hand of the present invention and corresponds to the acquisition hand 11a of the first embodiment. Therefore, the first acquisition hand 51a holds the unprocessed substrates W one by one from the carrier C and transports them to the path 24. The first acquisition hand 51a has a hand body 53 and a first guide member 52. The tip of the first acquisition hand 51a is provided with the first guide member 52 that abuts the end of the substrate W. The hand body 53 has a similar configuration to the hand body 31 of the first embodiment. The first guide member 52 has a similar configuration to the guide member 32 of the first embodiment. Therefore, the first guide member 52 has a thick portion and a thin portion. The first guide member 52 has a thickness that differs in parts in the height direction. The first acquisition hand 51a is a high-speed transport hand that transports the substrates W one by one from the carrier C that stores a plurality of substrates W in a horizontal position at a predetermined interval in the vertical direction Z.

[0134] The first returning hand 51b corresponds to the returning hand 11b in the first embodiment and has a similar configuration to the above-mentioned first acquiring hand 51a. The first acquiring hand 51a is a hand for acquiring an unprocessed substrate W from a carrier C, and the first returning hand 51b is a hand for returning a clean substrate W that has been subjected to a cleaning process to the carrier C.

[0135] The second acquisition hand 61a corresponds to the second hand of the present invention. The second acquisition hand 61a holds unprocessed substrates W one by one from the carrier C and transports them to the path 24. The first acquisition hand 51a and the second acquisition hand 61a have similar functions, but have different hand shapes (see Figs. 16 and 17). The second acquisition hand 61a has a hand body 63 and a second guide member 62. The hand body 63 has a flat shape so that it can enter between substrates. The tip of the second acquisition hand 61a is provided with a second guide member 62 that abuts against the end of the substrate W. The second guide member 62 is a tab provided at the tip of the hand body 63 and is a member that contacts the substrate W. The second guide member 62 is provided on the upper surface of the hand body 63. The second guide member 62 has a thick portion and a thin portion like the first guide member 52 described above. Therefore, the second guide member 62 has a thickness in the height direction that differs in parts. The wall portion of the thick portion of the second guide member 62 facing the base end of the second acquisition hand 61a is contactable with the edge (bevel portion) of the substrate W. The flat portion facing upwards of the thin portion of the second guide member 62 is contactable with the peripheral portion of the underside of the substrate. A guide member is also provided at the base end of the hand body 63 (not shown in FIG. 14). The guide member constitutes a contact portion of the second acquisition hand 61a that comes into contact with the substrate W. The second acquisition hand 61a is a low-speed transport hand that transports substrates W one by one from a carrier C that stores multiple substrates W in a horizontal position at a predetermined interval in the vertical direction Z.

[0136] The second returning hand 61b has the same configuration as the above-mentioned second obtaining hand 61a. That is, the second returning hand 61b has a hand body 63 and a second guide member 62. In the second returning hand 61b, the configuration in which the second guide member 62 is provided at the tip and base of the hand body 63, and the configuration in which the second guide member 62 has a thick part and a thin part are the same as the configuration of the second obtaining hand 61a. The second returning hand 61b of this example is provided to transport a clean substrate W that has been cleaned. By using different hands on the outward and return routes in the reciprocating motion of the substrate W, it becomes unnecessary to hold the substrate W after the cleaning process with the hand that holds the substrate W before the cleaning process. By providing the second returning hand 61b, the cleanliness of the substrate W after the cleaning process is maintained.

[0137] 15(a) shows the tip of the first acquisition hand 51a and the first return hand 51b, and FIG. 15(b) shows the tip of the second acquisition hand 61a and the second return hand 61b. The thickness A11 in the vertical direction Z at the tip of the first acquisition hand 51a and the first return hand 51b is the distance from the upper end of the thick part of the first guide member 52 to the lower end of the hand body 53. Similarly, the thickness A12 in the vertical direction Z at the tip of the second acquisition hand 61a and the second return hand 61b is the distance from the upper end of the thick part of the second guide member 62 to the lower end of the hand body 63. The thickness A12 in the height direction at the tip of the second acquisition hand 61a and the second return hand 61b is smaller than the thickness A11 in the height direction at the tip of the first acquisition hand 51a and the first return hand 51b. Therefore, the second acquisition hand 61a and the second return hand 61b can enter narrower gaps than the first acquisition hand 51a and the first return hand 51b. Such a configuration is advantageous when the substrates W to be transported are warped and close to each other. On the other hand, the first acquisition hand 51a and the first return hand 51b can transport substrates at a higher speed than the second acquisition hand 61a and the second return hand 61b. This point will be described later.

[0138] 16 is a plan view for explaining the first acquisition hand 51a and the first return hand 51b. The first acquisition hand 51a and the first return hand 51b have the same configuration as the acquisition hand 11a and the return hand 11b according to the first embodiment. That is, the first acquisition hand 51a and the first return hand 51b have a base 56, and a first holder 53a and a second holder 53b formed by branching the base 56. The first acquisition hand 51a and the first return hand 51b have a first holder 53a extending in the front-rear direction X to hold one end of the substrate W, and a second holder 53b extending in the front-rear direction X to hold the other end of the substrate W. The first guide member 52 is provided at the tip of the first holder 53a and the second holder 53b.

[0139] Guide members 54 are provided at the bases of the first holding body 53a and the second holding body 53b. Like the above-mentioned first guide member 52, the guide member 54 has a thick portion constituting a wall portion with which the end (bevel portion) of the substrate W can come into contact, and a thin portion constituting a flat portion with which the peripheral portion of the lower portion of the substrate can come into contact. The thickness of the thick portion of the guide member 54 is the same as that of the thick portion of the first guide member 52. The thickness of the thin portion of the guide member 54 is the same as that of the thin portion of the first guide member 52. The walls of the first guide member 52 and the guide member 54 are arranged to belong to an imaginary circle slightly larger than the substrate W. This allows the substrate W to fit into the receiving area for the substrate W formed by the thin portions of the first guide member 52 and the guide member 54.

[0140] The first acquisition hand 51a and the first return hand 51b have a pusher 55. The pusher 55 is provided at the tip of the base 56 and can push the substrate W held by the first guide member 52 and the guide member 54 forward. The pusher 55 can move backward to an open state, and can move forward to a closed state. In order for the first holder 53a and the second holder 53b to hold the substrate W, the pusher 55 is first opened to hold the substrate W by the first guide member 52 and the guide member 54. Then, the pusher 55 is closed to sandwich the substrate W between the first guide member 52 and the pusher 55. In this manner, the substrate W is held. On the other hand, the second acquisition hand 61a and the second return hand 61b do not have a pusher. Therefore, there is a clearance between the second guide member 62 of the second acquisition hand 61a and the substrate W held by the second guide member 62, which will be described later, and a guide member 64. The second obtaining hand 61a transports the substrate W while maintaining a clearance. The same applies to the second returning hand 61b.

[0141] 17 is a plan view for explaining the second acquisition hand 61a and the second return hand 61b. The second acquisition hand 61a and the second return hand 61b are provided with a base 66 and a first blade 63a and a second blade 63b formed by branching off the base 66. The second acquisition hand 61a and the second return hand 61b are provided with the first blade 63a extending in the front-rear direction X to hold one end of the substrate W, and the second blade 63b extending in the front-rear direction X to hold the other end of the substrate W. The second guide member 62 is provided at the tip of the first blade 63a and the second blade 63b.

[0142] A guide member 64 is provided at the base of each of the first blade 63a and the second blade 63b. Like the above-mentioned guide member 54, the guide member 64 has a thick portion constituting a wall portion with which the end (bevel portion) of the substrate W can come into contact, and a thin portion constituting a flat portion with which the peripheral portion of the lower portion of the substrate can come into contact. The thickness of the thick portion of the guide member 64 is the same as that of the thick portion of the second guide member 62. The thickness of the thin portion of the guide member 64 is the same as that of the thin portion of the second guide member 62. The walls of the second guide member 62 and the guide member 64 are arranged to belong to an imaginary circle slightly larger than the substrate W. This allows the substrate W to fit into the receiving area for the substrate W formed by the thin portions of the second guide member 62 and the guide member 64.

[0143] The first acquisition hand 51a and the second acquisition hand 61a have different shapes. That is, as can be seen from FIG. 16, the first holding body 53a and the second holding body 53b of the first acquisition hand 51a are tapered so that the thickness in the width direction Y increases from the tip to the base. With such a configuration, the rigidity of the first acquisition hand 51a is increased, and faster substrate transport can be achieved. The same effect is achieved with the first return hand 51b.

[0144] On the other hand, as can be seen from FIG. 17, the first blade 63a and the second blade 63b of the second acquisition hand 61a have a thickness in the width direction Y that does not change from the tip to the base. With such a configuration, the space R2 between the first blade 63a and the second blade 63b can be increased. Although the space R1 exists between the first holding body 53a and the second holding body 53b in the first acquisition hand 51a shown in FIG. 16, it is smaller than the space R2 because the first holding body 53a and the second holding body 53b are tapered. The space between the first holding body 53a and the second holding body 53b is smaller than the space between the first blade 63a and the second blade 63b.

[0145] Also, as can be seen by referring to FIG. 17, the separation distance A22 between the first blade 63a and the second blade 63b in the second acquisition hand 61a is larger than the separation distance A21 between the first holder 53a and the second holder 53b in the first acquisition hand 51a (see FIG. 17 and FIG. 16). In this way, the space R2 can be made larger than the space R1. And, by providing the wide space R2, the second acquisition hand 61a can reliably transport a substrate W that is difficult to transport compared to the first acquisition hand 51a. Specifically, the substrate W that is difficult to transport is a warped substrate W. The warped substrate W may be deformed into a concave shape toward the center of the substrate W, and thus it is more likely to come into contact with the hand during transportation. In this regard, the second acquisition hand 61a is not configured to provide the first blade 63a and the second blade 63b in a portion where the warped substrate is expected to come into contact with the hand. Therefore, the second obtaining hand 61a of this example can reliably transport even a more difficult-to-transport substrate W. The same effect is achieved with the second returning hand 61b.

[0146] The separation distance A21 is the distance from the first guide member 52 provided on the first holding body 53a to the first guide member 52 provided on the second holding body 53b. The separation distance A22 is the distance from the second guide member 62 provided on the first blade 63a to the second guide member 62 provided on the second blade 63b.

[0147] When the indexer robot IR transports the substrate W from the carrier C to the path 24, the first acquisition hand 51a or the second acquisition hand 61a is used. The first acquisition hand 51a or the second acquisition hand 61a enters between the first substrate W1 to be transported, which is held by the carrier C, and the second substrate W2 located below it, and then rises to acquire the first substrate W1. The acquired first substrate W1 is transported to the path 24.

[0148] When the indexer robot IR transports the substrate W from the path 24 to the carrier C, the first returning hand 51b or the second returning hand 61b is used. The first returning hand 51b or the second returning hand 61b acquires the substrate W to be transported that is held in the path 24, and enters the carrier C. The first returning hand 51b or the second returning hand 61b then descends to place the substrate W to be transported on the carrier C. The first returning hand 51b or the second returning hand 61b moves between the transported substrate W and the substrate W located below it, and retreats to leave the carrier C.

[0149] 12.Other configurations 1 includes, for example, control of the indexer robot IR. That is, the control unit 100 controls the forward and backward movements of the first acquiring hand 51a, the first returning hand 51b, the second acquiring hand 61a, and the second returning hand 61b, the opening and closing movement of the pusher 55, the movement of the arm 13 in the vertical direction Z, a mapping sensor described below, and a movement mechanism of the mapping sensor. The control unit 100 also selects which of the four types of hands is to be used for transport. The memory unit has the same configuration as that of the first embodiment.

[0150] 13. Circuit board transport flow Fig. 18 is a flow chart for explaining the operation of the substrate transfer apparatus of the present invention. Hereinafter, the manner in which the substrate transfer apparatus operates when a substrate cleaning process is performed by the substrate processing apparatus 1 of the present invention will be explained. Fig. 13 shows the manner in which a substrate W is transferred within the substrate processing apparatus 1. Fig. 13 will also be referred to as appropriate in the following explanation.

[0151] Step S11: When the carrier C to be processed is placed on the load port 10, the substrate transport device starts a mapping operation for the substrate W. This step is similar to step S1 in the first embodiment, and therefore a detailed description thereof will be omitted.

[0152] This step makes it possible to know how the comb member 7 of the carrier C holds the substrate W. The comb member 7 is provided with 25 protrusions, each of which is capable of holding a substrate W. For ease of explanation, it is assumed that the carrier C holds fewer than 25 substrates W. Of the substrates W held by the carrier C, a certain substrate W is at a distance of 1 cm to a substrate W located below it. 1 cm is the arrangement pitch of the protrusions on the comb member 7. And, of the substrates W held by the carrier C, another substrate W is at a distance of 2 cm to a substrate W located below it. Therefore, the comb member 7 has an empty protrusion that does not hold a substrate W, one substrate W is held by another protrusion at a position 1 cm above the empty protrusion, and the other substrate W is held by another protrusion at a position 1 cm below the empty protrusion. By the mapping operation, it is possible to recognize which part of the carrier C has a distance of 1 cm between the substrates, and which part of the carrier C has a distance of 2 cm between the substrates.

[0153] 18, when the hand is inserted between the substrates, if the distance between the substrates is 2 cm and there is sufficient space, the substrates are transported using the first acquisition hand 51a and first return hand 51b for high-speed transport. On the other hand, when the hand is inserted between the substrates, if the distance between the substrates is 1 cm and there is not sufficient space, the substrates are transported using the second acquisition hand 61a and second return hand 61b for low-speed transport.

[0154] Step S12: The indexer robot IR is moved to the rear of the carrier C. Then, the arm 13 of the indexer robot IR moves vertically. If there is a height of 2 cm between the substrate W to be transported and the substrate W below it, the first acquisition hand 51a is positioned at the height of the substrate W to be transported. The first acquisition hand 51a grasps the substrate W to be transported and delivers it to the path 24 (see arrow a in FIG. 13). At this time, the substrate W is transported at high speed. On the other hand, if there is a height of 1 cm between the substrate W to be transported and the substrate W below it, the second acquisition hand 61a is positioned at the height of the substrate W to be transported. The second acquisition hand 61a holds the substrate W to be transported and delivers it to the path 24. At this time, the substrate W is transported at low speed.

[0155] Step S13: The unprocessed substrate W held on the path 24 is transported by the center robot CR to the single-wafer processing chamber 5a (see arrow b in FIG. 13). The single-wafer processing chamber 5a performs a cleaning process on the substrate W. The processed substrate W is transported by the center robot CR to the path 24 (see arrow c in FIG. 13).

[0156] Step S14: The clean substrate W that has been cleaned is transported by either the first returning hand 51b or the second returning hand 61b. The substrate W transported to the path 24 by the first acquiring hand 51a in step S12 is returned from the path 24 to the carrier C by the first returning hand 51b. At this time, the substrate W is transported at high speed. Also, the substrate W transported to the path 24 by the second acquiring hand 61a in step S12 is returned from the path 24 to the carrier C by the second returning hand 61b (see arrow d in Figure 13). At this time, the substrate W is transported at low speed. The substrate W held by a certain protrusion on the comb member 7 of the carrier C is returned to the same protrusion after the substrate acquiring operation and the substrate returning operation.

[0157] Step S15: When the substrate W has been returned to the carrier C, the mapping operation of the substrate W is performed again in the same manner as in step S11. This completes the operation of the substrate transport apparatus of this example.

[0158] Note that the above description of the operations from step S1 to step S15 focuses on one substrate W. Therefore, when multiple substrates W are transported from the carrier C to perform cleaning processing on the substrates W, step S12 may be repeated before proceeding to step S13. Similarly, step S14 may also be repeated before proceeding to step S15.

[0159] In addition, when the position of the substrate W having a large warpage in the carrier C is known in advance, the first acquisition hand 51a and the second acquisition hand 61a can be selectively used according to the user's instruction. That is, for example, when all the substrates W in the carrier C are warped, the arm 13 is controlled to transport all the substrates W by the second acquisition hand 61a. On the other hand, when all the substrates W in the carrier C are flat, the arm 13 is controlled to transport all the substrates W by the first acquisition hand 51a. If the user inputs information about the shape of the substrate W at each position in the carrier C to the substrate transport device, the first acquisition hand 51a and the second acquisition hand 61a can be selectively used for operation in a single carrier C. The shape of the substrate W in this case means the degree of warpage of the substrate W.

[0160] 14. Effects of Example 2 The substrate transport device of this embodiment has two types of hands, a first acquisition hand 51a and a first return hand 51b for high-speed transport, and a second acquisition hand 61a and a second return hand 61b for low-speed transport, and is equipped with a control unit 100 that transports the substrate W by selectively using the first acquisition hand 51a and the first return hand 51b and the second acquisition hand 61a and the second return hand 61b. With this configuration, when the shape of the substrate W is nearly flat, the substrate W can be transported at high speed using the first acquisition hand 51a and the first return hand 51b, and when the substrate W is significantly warped, the substrate W can be transported at low speed using the second acquisition hand 61a and the second return hand 61b. In other words, the substrate transport device according to the present invention can transport the substrate W in a manner more suited to the actual state of the substrate W stored in the carrier C.

[0161] Furthermore, according to this example, the thickness A12 in the height direction at the tip of the second acquisition hand 61a and the second return hand 61b is smaller than the thickness A11 in the height direction at the tip of the first acquisition hand 51a and the first return hand 51b. With this configuration, even if the substrate W is significantly warped and the minimum distance between the substrates is short, the substrate W to be transported can be transported more reliably by using the second acquisition hand 61a and the second return hand 61b.

[0162] According to this example, the space R1 between the first holder 53a and the second holder 53b in the first acquisition hand 51a and the first return hand 51b is smaller than the space R2 between the first blade 63a and the second blade 63b in the second acquisition hand 61a and the second return hand 61b. With this configuration, the first acquisition hand 51a and the first return hand 51b can hold the substrate W more reliably, so that the substrate W can be transported at high speed. On the other hand, the second acquisition hand 61a and the second return hand 61b can reliably hold the warped substrate W between the first blade 63a and the second blade 63b.

[0163] According to this example, the first acquisition hand 51a and the first return hand 51b have pushers 55 that grip the substrate W. This allows the first acquisition hand 51a and the first return hand 51b to reliably grip the substrate W and transport it at high speed. Furthermore, the second acquisition hand 61a and the second return hand 61b do not have pushers. This simplifies the device configuration and reduces the thickness in the height direction of the second acquisition hand 61a and the second return hand 61b.

[0164] 15. Modifications of the present invention The present invention is not limited to the above configuration, but can be modified as follows.

[0165] <Variation 1> In the first embodiment, the first substrate W1 that is determined to be untransportable is left on the carrier C, but the present invention is not limited to this configuration, and the first substrate W1 may be transported. In this modified example, when the first substrate W1 remains on the carrier C after the second substrate W2 is transported from the carrier C, the first substrate W1 is transported by the acquisition hand 11a. FIG. 19 shows the first substrate W1 warped downward and the second substrate W2 placed on the comb-shaped member 7 of the carrier C below the first substrate W1. The third substrate W3 is located further below the second substrate W2 on the comb-shaped member 7. The distance between the first substrate W1 and the second substrate W2 is D5 as measured by the sensor holding member 21. The distance D5 is small enough that the acquisition hand 11a and the return hand 11b cannot enter between the first substrate W1 and the second substrate W2. Therefore, as long as the second substrate W2 is present on the carrier C, the first substrate W1 cannot be transported from the carrier C.

[0166] Meanwhile, the distance between the second substrate W2 and the third substrate W3 is D1 as measured by the sensor holding member 21. The distance D1 is large enough that the acquiring hand 11a and the returning hand 11b can enter between the second substrate W2 and the third substrate W3. Therefore, the second substrate W2 can be transported from the carrier C regardless of the presence of the third substrate W3.

[0167] FIG. 20 shows the state of the carrier C after the second substrate W2 is transported from the carrier C. After the second substrate W2 is transported, the first substrate W1 and the third substrate W3 remain on the carrier C. Between the first substrate W1 and the third substrate W3, there is an empty protrusion of the comb-shaped member 7. Therefore, the distance D6 between the first substrate W1 and the third substrate W3 is at least greater than the distance D1. That is, the acquiring hand 11a and the returning hand 11b can be inserted between the first substrate W1 and the third substrate W3. Therefore, even if the carrier C is in the state shown in FIG. 19, if the second substrate W2 and the first substrate W1 are transported in this order, the first substrate W1 that is temporarily untransportable can also be transported from the carrier C. Note that when returning the substrate W to the carrier C, the first substrate W1 and the second substrate W2 may be transported in this order.

[0168] In the above-mentioned configuration, if the first substrate W1 that was previously determined to be untransportable remains on the carrier C after the second substrate W2 has been transported from the carrier C, the first substrate W1 is transported by the acquiring hand 11a and the returning hand 11b. With this configuration, the first substrate W1 will not end up remaining on the carrier C.

[0169] <Variation 2> In the above-mentioned first embodiment, the relationship between the speed at which the sensor holding member 21 enters between the substrates and the speed at which the acquiring hand 11a and the returning hand 11b enter between the substrates is not mentioned. In this regard, the entering speed of the acquiring hand 11a and the returning hand 11b can be made faster than the entering speed of the sensor holding member 21. According to this modification, the sensor holding member 21 is caused to enter between the first substrate W and the second substrate W2 at a first speed, and the acquiring hand 11a is caused to enter between the first substrate W1 and the second substrate W2 at a speed faster than the first speed. In the configuration according to this modification, the acquiring hand 11a and the returning hand 11b enter between the substrates at a speed faster than the sensor holding member 21, so that the effect of speeding up the substrate transport process is obtained. In addition, by slowing down the entering speed of the sensor holding member 21, the sensor holding member 21 does not come into contact with the substrate W even if the sensor holding member 21 is caused to enter between the narrow substrates as described in FIG. 11(b). On the other hand, the acquiring hand 11a and the returning hand 11b can move at a high speed since they do not enter between substrates that are too close to each other to allow transportation.

[0170] <Variation 3> The second embodiment described above may further include the sensor holding member 21 of the first embodiment. The sensor holding member 71 in FIG. 21 is a member that enters between adjacent substrates W. The sensor holding member 71 holds a first sensor 81 that measures the distance to the upper substrate W and a second sensor 82 that measures the distance to the lower substrate W. The sensor holding member 71 enters between the substrates to measure the minimum distance between the substrates. Based on the measured distance, it may be possible to determine which hand is used to transport the first substrate W1. That is, when the first substrate W1 is significantly warped and it is better to transport the substrate at a low speed, the second acquisition hand 61a transports the first substrate W1. When the first substrate W1 is significantly warped and there is no problem with transporting the substrate at a high speed, the first acquisition hand 51a transports the first substrate W1. When the first substrate W1 is significantly warped, the distance between the first substrate W1 and the second substrate W2 is short, so it is better to transport the substrate at a low speed. Furthermore, if the first substrate W1 is significantly warped, it is more likely that the first substrate W1 will come into contact with the hand, so it is better to transport the first substrate W1 using the second obtaining hand 61a, which has a larger space R2 between the first blade 63a and the second blade 63b. On the other hand, if the first substrate W1 is flat, it is better to transport the substrate at high speed. This can increase the processing capacity of the substrate transport device.

[0171] <Modification 4> In the above-described first embodiment, as shown in Fig. 22, the acquiring hand 11a may also serve as the sensor holding member 21. That is, the acquiring hand 11a is configured to have a first sensor 41 and a second sensor 42 attached thereto. According to this configuration, the sensor group 43 is provided at the tip of the hand body 31, closer to the guide member 32. With this configuration, it is possible to provide a substrate transport device with a simple configuration by omitting the sensor holding member 21. [Explanation of symbols]

[0172] 1. Substrate Processing Equipment 3. Indexer Blocks 5 Processing Blocks 5a Single wafer processing chamber 7 Comb-shaped member 10 Loading Port 11a Acquiring Hand 11b Return Hand 12 Arm 13 Arm 21 Sensor holding member 23 Retaining member body 24 Pass 25a 1st protrusion 25b Second protrusion 26 Base 31 Hand body 32 Guide member 33a 1st holding body 33b Second holding body 34 Guide member 35 Pusher 36 Base 41 First Sensor 42 Second Sensor 43 Sensors 51a First Acquisition Hand 51b 1st Return Hand 52 First guide member 53 Hand body 53a 1st holding body 53b Second holding body 54 Guide member 55 Pusher 56 Base 61a Second Acquisition Hand 61b Second Return Hand 62 Second guide member 63 Hand body 63a 1st Blade 63b 2nd Blade 64 Guide member 66 Base 71 Sensor holding member 81 First Sensor 82 Second Sensor 100 Control section A1 Thickness A2 Thickness A11 Thickness A12 Thickness A21 Separation distance A22 Separation distance C Career CR Center Robot IR Indexer Robot R1 space R2 space W substrate W1 First board W2 Second board W3 3rd board X Anteroposterior direction Y Width direction Z vertical direction

Claims

1. a hand that stores a plurality of substrates in a horizontal position at a predetermined interval in a vertical direction and holds and transports the substrates one by one by entering between adjacent substrates vertically from a carrier having an opening on one side for removing and storing the substrates; a sensor holding member which is a member that enters between vertically adjacent substrates and includes a first sensor that measures the distance to the upper substrate and a second sensor that measures the distance to the lower substrate; a control unit that controls the hand and the sensor holding member to move forward and backward between the opening of the carrier and adjacent substrates vertically; The control unit is by inserting the sensor holding member between a first substrate to be transported and a second substrate located below the first substrate, a minimum distance between the substrates is measured from the sum of a first minimum distance of the substrate at a first measurement position where the first sensor is closest to the first substrate and a second minimum distance of the substrate at a second measurement position where the second sensor is closest to the second substrate; When the hand is inserted between the first substrate and the second substrate, the hand insertion height is adjusted according to the minimum distance between the substrates so that both the distance from the hand to the first substrate and the distance from the hand to the second substrate are equal to or greater than a predetermined value. A substrate transport device comprising:

2. 2. The substrate transport apparatus according to claim 1, a guide member at a tip end of the hand for contacting an edge of the substrate; the first sensor and the second sensor are provided at a tip end of the sensor holding member, The thickness of the sensor holding member in the height direction at the tip end is smaller than the thickness of the hand in the height direction at the tip end. A substrate transport device comprising:

3. 2. The substrate transport apparatus according to claim 1, the first sensor measures a distance while being moved from an end of the first substrate located at an opening of the carrier to a depth of the carrier; the second sensor measures a distance while being moved from an end of the second substrate located at an opening of the carrier to a depth of the carrier; The control unit adjusts the entry height of the hand so that at a first measurement position where the first substrate and the first sensor are closest to each other and at a second measurement position where the second substrate and the second sensor are closest to each other, the distance from the hand to the first substrate and the distance from the hand to the second substrate are both equal to or greater than a predetermined value. A substrate transport device comprising:

4. 4. The substrate transport device according to claim 3, The control unit adjusts an entry height of the hand so that a distance from the hand to the first substrate at the first measurement position and a distance from the hand to the second substrate at the second measurement position are equal to each other. A substrate transport device comprising:

5. 2. The substrate transport apparatus according to claim 1, The sensor holding member does not carry a substrate. A substrate transport device comprising:

6. 4. The substrate transport device according to claim 3, When a distance between the first substrate and the second substrate is short and a distance from the hand to the first substrate at the first measurement position and a distance from the hand to the second substrate at the second measurement position cannot be made equal to or greater than a predetermined value at the same time, the control unit does not allow the hand to enter between the first substrate and the second substrate. A substrate transport device comprising:

7. 2. The substrate transport apparatus according to claim 1, an upper surface of the sensor holding member is located above a lower end of the first sensor, The lower surface of the sensor holding member is located lower than the upper end of the second sensor. A substrate transport device comprising:

8. 2. The substrate transport apparatus according to claim 1, the hand includes a first holder that holds one end of the substrate and a second holder that holds the other end of the substrate; the sensor holding member includes at least two sensor groups each including the first sensor and the second sensor; a first sensor group for measuring a distance between the first substrate and the second substrate at an approach position of the first holder; A second sensor group measures the distance between the first substrate and the second substrate at the approach position of the second holder. A substrate transport device comprising:

9. 9. The substrate transport apparatus according to claim 8, The sensor holding member includes a first protruding portion extending to correspond to the first holding body and a second protruding portion extending to correspond to the second holding body. A substrate transport device comprising:

10. 10. The substrate transport apparatus according to claim 9, The sensor holding member includes the sensor group at a tip of the first protrusion, and the sensor group at a tip of the second protrusion. A substrate transport device comprising:

11. 10. The substrate transport apparatus according to claim 9, The sensor holding member is The first sensor and the second sensor are provided at the same position of the first protrusion, The first sensor and the second sensor are provided at the same position of the second protrusion. A substrate transport device comprising:

12. 2. The substrate transport apparatus according to claim 1, When a distance between the first substrate and the second substrate is short and the sensor holding member cannot be inserted between the first substrate and the second substrate, the control unit does not allow the hand to enter between the first substrate and the second substrate. A substrate transport device comprising:

13. 2. The substrate transport apparatus according to claim 1, The control unit, when the first substrate remains in the carrier after the second substrate is transported from the carrier, causes the hand to transport the first substrate. A substrate transport device comprising:

14. 2. The substrate transport apparatus according to claim 1, The control unit is The sensor holding member is inserted between the first substrate and the second substrate at a first speed; The hand is inserted between the first substrate and the second substrate at a second speed that is faster than the first speed. A substrate transport device comprising:

15. 2. The substrate transport apparatus according to claim 1, The sensor holding member is in the same position as the hand before entering between the substrates. A substrate transport device comprising:

16. 2. The substrate transport apparatus according to claim 1, The hand also serves as the sensor holding member, The first sensor and the second sensor are attached to the hand. A substrate transport device comprising:

17. The substrate transport device according to claim 1 ; a processing unit that performs a predetermined process on the substrate transported by the substrate transport device. The substrate processing apparatus according to claim 1,

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