JP6700124B2 - Conveying method for conveying objects to be conveyed - Google Patents

Description

  The present invention relates to a transfer method for transferring an object to be transferred, and more particularly to a transfer method for transferring an object to be processed such as a semiconductor wafer, a liquid crystal substrate, and an organic EL element to a processing chamber.

  For example, in a manufacturing process of a semiconductor device, a liquid crystal panel, etc., a film forming process, an etching process, an oxidizing process, etc. on an object to be processed such as a semiconductor substrate or a liquid crystal substrate (hereinafter, the semiconductor substrate or the liquid crystal substrate is simply referred to as “wafer”). The various types of processing are performed in individual processing devices. When loading/unloading a wafer to/from the processing apparatus, a transfer apparatus having a transfer arm as a holding unit for holding the wafer is usually used. There are various types of transfer devices, but, for example, a single-joint arm or a multi-joint arm that moves the holding part back and forth by extending and retracting is often used.

  In such a transfer apparatus, for example, a transfer arm that holds the wafer when transferring the wafer in and out of the processing apparatus transfers the wafer, and at that time, the wafer is accurately moved to a desired position on the transfer arm. It is required to align and deliver the items. Various methods have been proposed as a wafer alignment technique performed at each location in such a substrate processing system.

  For example, Patent Document 1 discloses a technique in which the edge of a wafer is detected by three edge sensors, the center position of the wafer is calculated from the detected position information, and alignment is performed based on the calculated center position. In the present technology, a transmissive sensor having a light projecting unit and a light receiving unit is used as a sensor, and an optical fiber is used for signal transmission to the sensor.

  Further, for example, in Patent Document 2, a transmission type sensor for detecting a peripheral edge of a wafer is provided in a hand portion (arm tip portion) of a transfer device, a center position of the wafer is obtained from the sensor information, and the wafer is placed on the wafer. A technique is disclosed in which a wafer is placed by aligning the center of a predetermined position with the center position of the wafer.

  Further, for example, in Patent Document 3, a sensor for detecting a wafer is attached to the tip of a supporting member of a transfer device, a deviation amount between the detected central position of the wafer and a reference position is obtained, and the deviation amount is taken into consideration. A technique is disclosed in which a support member is moved to a position to support a wafer and the wafer is taken out from a cassette.

Japanese Patent Laid-Open No. 8-64654 JP-A-11-195686 JP, 9-134944, A

  However, in the technique described in Patent Document 1, the edge sensor used for the alignment needs to be provided along with the rod, so that the equipment configuration becomes complicated. In addition, when the position is adjusted, the center position is calculated, and if the three points obtained by the edge sensor do not match, the calculation process is performed again. There is a risk that the load such as

  Further, the technique described in Patent Document 2 is a technique for mounting a wafer at a predetermined mounting position, and does not make any reference to alignment when holding the wafer in the hand portion. Further, in the technique described in Patent Document 3, a sensor attached to the hand member is used to obtain the positional displacement amount of the substrate in the cassette, and the substrate is supported and taken out at a position in consideration of the displacement amount. However, the calculation means is used to calculate the amount of positional deviation, and the load of the CPU or the like as the calculation means may increase as in Patent Document 1.

For example, in a system that performs various types of processing such as film formation processing, etching processing, and oxidation processing on an object to be processed (wafer) such as a semiconductor substrate or a liquid crystal substrate, a plurality of places such as a load lock chamber for waiting the wafer are provided. It is common to have In such a standby place, a predetermined position for keeping the wafer in a standby state is defined, and the transfer device for transferring the wafer assumes that the wafer is in a standby position at the predetermined position. Carry out including delivery.
However, a wafer in a heated state may be loaded into the standby place, and at that time, the wafer is cooled, for example, under room temperature conditions while waiting in the standby place. In such a case, the wafer may be slightly warped, and the wafer may be displaced from a predetermined standby position during standby.
In such a case, there is a demand for a technique capable of holding the wafer at a predetermined position of the transfer device by a simple means without requiring a complicated calculation process.

  In view of such circumstances, an object of the present invention is to determine whether or not a transfer target object is placed at a specified position in a transfer device that transfers the transfer target object, without performing a complicated calculation or the like. An object of the present invention is to provide a transfer method capable of efficiently mounting an object to be transferred at a desired position on the device.

In order to achieve the above object, according to the present invention, there is provided a transport method for transporting a transport object in a transport device including a transport pick, the method including inserting the transport pick into a predetermined position below the transport object. And a step of determining whether or not the transport object is located at a specified position where the transport pick can hold the transport object at the predetermined position, and the transport pick has three or more locations. Is provided with a conveyance object presence/absence detection sensor, and the conveyance object has a circular shape, and the conveyance object presence/absence detection sensors are provided at three or more locations on a circumference of a concentric circle having a predetermined diameter on the conveyance pick. The conveyance target presence/absence detection sensor is arranged at equal intervals in the circumferential direction of the concentric circle, the concentric circles have a smaller diameter than the outer circumference circle of the conveyance target , and the conveyance target presence/absence detection sensor When it is determined by detection that the transport target is located at the specified position, the transport pick is raised to hold the transport target by the transport pick, and the transport target presence/absence detection sensor detects the transport target. When it is determined that the object to be conveyed is not located at the specified position, the object to be conveyed is positioned within the specified position by the exploring operation of the transfer pick, and then the transfer pick is raised to move the object. A conveyance method is provided, which is characterized in that an object to be conveyed is held by a pick.

  The search operation of the transport pick is performed in a direction such that the transport target presence/absence detection sensor that has not detected the transport target among the transport target presence/absence detection sensors provided at the three or more locations detects the transport target. It may be performed by moving the transport pick.

  The conveyed object presence/absence detection sensor may be a reflection type fiber sensor.

  According to the present invention, in a transfer device that transfers an object to be transferred, it is determined whether or not the object to be transferred is placed at a specified position without performing complicated calculations, and the object is transferred to a desired position of the transfer device. It is possible to efficiently mount the object.

It is a schematic plan view which shows the structure of the substrate processing system to which the conveying apparatus according to the present embodiment is applied. It is a schematic perspective view of a wafer conveyance device. It is a schematic explanatory drawing of a conveyance pick. It is a schematic explanatory drawing regarding holding|maintenance of the wafer by a conveyance pick. It is a schematic diagram showing another example of a wafer search operation. It is a schematic plan view of the conveyance pick which concerns on the reference example 1. 7 is a schematic explanatory diagram related to the operation of the transport pick according to Reference Example 1. FIG. 8 is a schematic explanatory diagram related to wafer position correction in Reference Example 1. FIG. 7 is a schematic side view of a transport pick according to Reference Example 2. FIG. FIG. 10 is an explanatory diagram regarding a technique for aligning a transfer pick and a wafer according to Reference Example 3.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, and duplicate description will be omitted.

  FIG. 1 is a schematic plan view showing the configuration of a substrate processing system 1 to which a transfer device according to this embodiment is applied. In the substrate processing system 1 of the present embodiment, the wafer W as a substrate is subjected to predetermined processing.

  The substrate processing system 1 has a cassette station 2 for loading/unloading the wafer W to/from the substrate processing system 1 in units of a cassette C, and a processing station 3 for processing the wafer W as an object to be processed, for example. The cassette station 2 and the processing station 3 are integrally connected via a load lock chamber 4.

  The cassette station 2 includes a cassette placing section 10 and a transfer chamber 11 provided adjacent to the cassette placing section 10. A plurality of, for example, three cassettes C capable of accommodating a plurality of wafers W can be mounted on the cassette mounting portion 10 in the X direction (left and right direction in FIG. 1). A wafer transfer arm 12 is provided in the transfer chamber 11. The wafer transfer arm 12 is movable in the up-down direction, the left-right direction, and around the vertical axis (θ direction in the drawing), and can transfer the wafer W between the cassette C of the cassette mounting unit 10 and the load lock chamber 4. .. At the end of the transfer chamber 11 on the negative side in the X direction, an alignment device 13 that recognizes a notch of the wafer W and positions the wafer is provided.

  The processing station 3 includes a plurality of processing chambers 20 for performing a predetermined process on the wafer W and a polygonal (an octagonal shape in the illustrated example) vacuum transfer chamber 21. The processing chambers 20 are arranged so as to surround the vacuum transfer chamber 21. The load lock chamber 4 is connected to the vacuum transfer chamber 21.

  In the vacuum transfer chamber 21, a wafer transfer device 31 that transfers a target object and a wafer W as an object to be transferred is provided. The wafer transfer device 31 is provided with a transfer pick 40 as a holding unit for holding the wafer W and an arm mechanism 32 that can be swiveled and expanded and contracted, and transfers the wafer W between the load lock chamber 4, the vacuum transfer chamber 21, and the processing chamber 20. It can be transported by. Although FIG. 1 illustrates the case where only one arm mechanism 32 is provided in the center of the vacuum transfer chamber 21, a plurality of arm mechanisms 32 may be provided.

Here, the detailed configuration of the wafer transfer device 31 including the arm mechanism 32 will be described with reference to FIG. FIG. 2 is a schematic perspective view of the wafer transfer device 31.
The arm mechanism 32 has a linear first arm 34 and a linear second arm 35 connected to the first arm 34. A base end portion of the first arm 34 is connected to the central hub 36, and the first arm 34 is configured to be rotatable about the center of the central hub 36 as a central axis. A joint portion 37 is provided between the tip end portion of the first arm 34 and the base end portion of the second arm 35, and the second arm 35 is configured to be rotatable about the joint portion 37 as a central axis. There is.

  A transfer pick 40 as a holding unit for holding the wafer W is provided at the tip of the second arm 35. A motor 38 is connected to the central hub 36, and the motor 38 expands and contracts the arm mechanism 32 in the horizontal direction, and the transport pick 40 is movable in the horizontal direction. The motor 38 moves the arm mechanism 32 in the vertical direction, and the transport pick 40 is movable in the vertical direction. An encoder (not shown) is provided on the motor 38, and the encoder can grasp the horizontal movement amount of the transport pick 40, that is, the horizontal position and the vertical position of the transport pick 40.

  Further, as shown in FIG. 1, it is a boundary between the processing apparatus 20 and the vacuum transfer chamber 21, and the loading/unloading port 25 when the wafer W is transferred (loaded/unloaded) to/from the processing apparatus 20 is provided for each processing apparatus 20. Sensors 26, 26 for detecting the passage of the wafer W are provided on both sides of the loading/unloading port 25. The sensor 26 includes a light emitting unit and a light receiving unit, and the light emitting unit and the light receiving unit are arranged to face each other in the vertical direction with the transport pick 40 (wafer W) interposed therebetween. Then, the sensor 26 detects the wafer W held by the transfer pick 40. The configuration of the sensor 26 is not limited to this embodiment, and any configuration can be adopted. For example, the sensor 26 is a sensor in which a light emitting unit and a light receiving unit are integrally configured, and may be arranged above the carry-in/out port 25.

  In the substrate processing system 1 according to the present embodiment described above with reference to FIG. 1, substrates are transferred and delivered at various places. For example, the wafer W is transferred using the wafer transfer arm 12 between the cassette placing section 10 and the cassette C in the cassette station 2. At that time, the wafer W may be exchanged between the wafer transfer arm 12 and the alignment device 13. Further, the wafer W is transferred between the load lock chamber 4, the vacuum transfer chamber 21 and the processing chamber 20 by using the wafer transfer device 31.

In such a wafer W transfer system, the wafer W placed on various positions such as the cassette C, the alignment device 13, the load lock chamber 4, and the processing chamber 20 is transferred to the wafer transfer arm 12 or the arm mechanism. Although the holding work is performed by 32, the wafer W is not always placed in a predetermined position at that time. For example, in the cassette C or the load lock chamber 4, the heated wafer W may be cooled (cooling), and the wafer W may be warped or distorted due to the cooling, so that the wafer W is deviated from a predetermined position. In some cases.
When the wafer W deviates from a predetermined position, it is necessary to perform alignment between the wafer W and each arm (transport pick) in order to reliably hold the wafer W on each arm (transport pick). is there. Therefore, the structure of the arm for holding the wafer W reliably will be described below. The transfer pick 40 of the wafer transfer apparatus 31 will be described below as an example, but the configuration according to the present embodiment can be applied to all transfer picks in the substrate processing system (for example, the pick of the wafer transfer arm 12). Is.

Next, with reference to FIG. 3, a detailed configuration of the transfer pick 40 as a holding unit for the wafer W will be described. 3A and 3B are schematic explanatory views of the transport pick 40. FIG. 3A is a schematic plan view and FIG. 3B is a schematic side view. Note that FIG. 3A shows a state in which the wafer W is held by a solid line.
As shown in FIG. 3, the transport pick 40 as a holding unit has a substantially U-shaped main body 41 and a support plate 42 that supports the main body 41. The main body portion 41 is connected to the support plate 42 by a fastening member such as a bolt (not shown). Further, the support plate 42 is provided with a pad drive unit 45 (see a chain line in the drawing) having an air cylinder (not shown), and the drive of the pad drive unit 45 causes the pad member 50, which will be described later, to move the outer edge of the wafer W. Fixed and unfixed.

  Further, the wafer W is placed on the upper surface of the main body 41 at two tip portions of the main body 41 and at two locations of the root, and when holding the wafer W, the wafer W is fixed at a predetermined position of the transfer pick 40. Movable pad members 50 for holding them are attached to, for example, four positions shown in the figure. That is, when the wafer W is placed at a predetermined position on the transfer pick 40, the outer edge of the wafer W is fixed by these pad members 50 as shown in FIG. It is configured to prevent such problems.

In addition, a conveyance target presence/absence detection sensor 60 (hereinafter referred to as wafer presence/absence) for detecting the presence or absence of the wafer W as a conveyance target is provided at a total of three places, that is, in the vicinity of two front end portions of the main body portion 41 and one place of the root portion. The detection sensor 60 is also described). The wafer presence/absence detection sensor 60 is, for example, a reflection type fiber sensor provided in the main body 41 in an embedded manner.
It is preferable that these wafer presence/absence detection sensors 60 are attached on the circumference of the concentric circle S, and further, they are arranged at equal intervals (that is, 120° intervals in the circumferential direction) on the circumference. It is preferable. Further, regarding the arrangement configuration of these wafer presence/absence detection sensors 60, it is preferable that the concentric circle S has a slightly smaller diameter than the outer circumference circle of the wafer W. For example, when the diameter of the wafer W is 300 mm, the diameter of the concentric circle S is 297 mm.

  The number and arrangement of the wafer presence/absence detection sensors 60 described here are merely examples, and the present invention is not limited to this. For example, the wafer presence/absence detection sensor 60 may be attached to any number of locations such as three or more locations, and the location thereof may be any location as long as it is on the main body 41 of the transport pick 40.

  Next, with reference to FIG. 4, the operation of the transfer pick 40 configured as described above and the alignment when holding the wafer W will be described. FIG. 4 is a schematic explanatory diagram regarding holding of the wafer W by the transport pick 40, and illustrates the movement of the transport pick 40 in time series in the order of (a) to (d). Note that the description shown in FIG. 4 is a process performed when the position of the wafer W is deviated from a predetermined position when the wafer W is held by the transfer pick 40 for transfer. It is not necessary to perform the alignment when it is at a more predetermined position.

  First, as shown in FIG. 4A, the transfer pick 40 moves toward the wafer W that is the transfer target (the direction of the arrow in the drawing), and the transfer pick 40 is inserted into the lower space of the wafer W. .. At this time, the lower surface of the wafer W and the transfer pick 40 are separated from each other so that the pad member 50 provided on the transfer pick 40 does not contact the wafer W.

For example, when the wafer W is deviated from a predetermined position (specified position), at least one of the three wafer presence/absence detection sensors 60 does not detect the wafer W, as shown in FIG. 4B. . In such a case, when holding the wafer W, it is considered that the wafer W is not placed at the specified position, and further detection is performed using the wafer presence/absence detection sensor 60.
When all the wafer presence/absence detection sensors 60 detect the wafer W at this time, it is determined that the wafer W is present at the specified position, the transport pick 40 moves up, and the pad member 50 moves the wafer W onto the transport pick 40. The wafer W will be held at.

  Next, when the wafer W is not detected by at least one of the wafer presence/absence detection sensors 60, various wafer probing operations are performed. In the present embodiment, as an example of the wafer searching operation, of the wafer presence/absence detection sensors 60 provided at three locations, the direction in which the sensor that has not detected the wafer W detects the wafer W (here, in FIG. The transfer pick 40 is moved in the right direction (indicated by the middle arrow), and the transfer pick 40 is moved to a position where all the wafer presence/absence detection sensors 60 detect the wafer W. That is, the wafer searching operation is performed until the relative positions of the transfer pick 40 and the wafer W match.

  Then, as shown in FIG. 4D, after the transfer pick 40 is moved to a position where all the wafer presence/absence detection sensors 60 detect the wafer W, the transfer pick 40 moves upward and the pad member 50. Thus, the wafer W is held. When the wafer transfer device 31 is operated in such a state, the wafer W is transferred to a desired position while being held by the transfer pick 40.

The wafer W is held and transferred by the transfer pick 40 through the steps described with reference to FIG.
According to such a method of transporting the wafer W, the wafer W can be detected and detected only by the wafer presence/absence detection sensors 60 attached at three positions without performing complicated position information calculation (for example, wafer center position calculation). It is possible to determine whether or not is present in the specified position. In addition, the relative position between the transfer pick 40 and the wafer W can be obtained only by performing a simple wafer searching operation such as moving the transfer pick 40 in a direction in which the sensor that has not detected the wafer W detects the wafer W. Can be easily matched, and the wafer W can be efficiently placed at a desired position on the transfer pick 40 and transferred. Therefore, when the wafer W is transferred, the wafer W is not accurately held and is prevented from being damaged or dropped, so that the operation efficiency and the productivity are improved.

  Although an example of the embodiment of the present invention has been described above, the present invention is not limited to the illustrated embodiment. It is obvious to those skilled in the art that various changes or modifications can be conceived within the scope of the idea described in the claims, and naturally, they also belong to the technical scope of the present invention. Understood.

For example, in the above-described embodiment, the case where the wafer presence/absence detection sensors 60 are attached to three positions on the circumference of the concentric circle S of the transport pick 40 at equal intervals (at intervals of 120° in the circumferential direction) has been illustrated and described. Is not limited to such a configuration.
That is, the number of the wafer presence/absence detection sensors 60 may be three or more. This is because if the sensors are provided at only two locations, a complicated process such as calculating the center position of the wafer W during alignment may be required.

  Further, from the viewpoint of performing a simple wafer probing operation, it is desirable that the plurality of wafer presence/absence detection sensors 60 be mounted at equal intervals on the circumference of a concentric circle, but some arrangement changes and the like are possible. For example, in the above-described embodiment, when the diameter of the wafer W is 300 mm, the sensor is provided on the circumference of the concentric circle S having the diameter of 297 mm. However, the sensor may be provided on the circumference of the concentric circle having the diameter of 303 mm. , May be provided on both the circumferences of a concentric circle having a diameter of 297 mm and a concentric circle having a diameter of 303 mm. The arrangement of the wafer presence/absence detection sensor 60 may be suitably determined depending on factors such as the movable area of the pad member 50. However, if a plurality of wafer presence/absence detection sensors 60 are installed in close proximity to each other, various calculation steps are required at the time of alignment as in the case where there are only two sensors. Need to be installed.

Further, as an example of the wafer searching operation, when the transfer pick 40 is moved in such a direction that one of the wafer presence/absence detection sensors 60 provided at three locations, which has not detected the wafer W, detects the wafer W. However, the wafer searching operation is not limited to such a method.
FIG. 5 is a schematic view showing another example of the wafer searching operation. When the wafer W is not detected by the plurality of wafer presence/absence detection sensors 60, an operation for searching for a position where all the wafer presence/absence detection sensors 60 detect the wafer W is performed by moving the transfer pick 40 arbitrarily. It is also possible to perform a so-called spiral operation as shown in FIG.

(Reference example)
Further, in the above-described embodiment, the case where the wafer presence/absence detection sensors 60 are attached to three positions on the circumference of the concentric circle S in the transport pick 40 at equal intervals (at intervals of 120° in the circumferential direction) has been described. There is room for further study on the configuration of the sensor for performing the above. Therefore, as a reference example, another configuration of the sensor provided on the transport pick 40 will be described below.

(Reference example 1)
FIG. 6 is a schematic plan view of the transport pick 40a according to the first reference example. Since each component of the transport pick 40a except the sensor has the same functional configuration as that of the transport pick 40 described in the above embodiment, the same reference numerals are given and the description thereof is omitted.

  A wafer presence/absence detection sensor 70 is attached to the transport pick 40a according to the reference example 1 at two locations of a substantially U-shaped pick tip portion. The wafer presence/absence detection sensor 70 is, for example, a reflection type fiber sensor provided in the main body 41 in an embedded manner. When the transport pick 40a configured as shown in FIG. 6 is inserted below the wafer W to be held, the wafer pick-up detection sensors 70 at two locations detect four locations at the outer edge of the wafer W. Measurement is performed.

  FIG. 7 is a schematic explanatory diagram regarding the operation of the transport pick 40a, and illustrates the movement of the transport pick 40a in time series in the order of (a) to (c). First, as shown in FIG. 7A, the transfer pick 40a is inserted below the wafer W. Then, as shown in FIG. 7B, the points (two points) at which the wafer presence/absence detection sensors 70 at two points first measured the outer edge portion of the wafer W are recorded. Then, as shown in FIG. 7C, the insertion of the transfer pick 40a is continued until the two wafer presence/absence detection sensors 70 no longer detect the wafer W at the outer edge of the wafer W (two points). The measurement by the wafer presence/absence detection sensor 70 is completed.

  In the present reference example 1, the same measurement is performed in advance regarding the case where the wafer W is arranged at the specified position (desired ideal position), and the result is compared with the result measured by the method shown in FIG. 7. Then, from the comparison between the difference and the specified position where the wafer W should be arranged, the actual position of the wafer W is calculated, and the wafer W is accurately held by carrying out the correction so that the transfer pick 40a can be held. The operation of is realized.

  FIG. 8 is a schematic explanatory diagram relating to the position correction of the wafer W in the present reference example 1, and is a graph showing the ON and OFF timings of the wafer detection signals by the two wafer presence/absence detection sensors 70. Note that the graph of FIG. 8 shows data when the wafer W is at the specified position (ideal Wafer) and data when the wafer W is at the shifted position (shifted Wafer). As shown in FIG. 8, when the wafer W is at the displaced position, the measurement data of the wafer outer edge portion at four locations by the wafer presence/absence detection sensor 70 is displaced from the data at the ideal position. By moving the transfer pick 40a to a position that corrects the difference, the wafer W can be positioned at a specified position above the transfer pick 40a, and the wafer W is preferably held. Is possible.

(Reference example 2)
FIG. 9 is a schematic side view of the transport pick 40b according to the second reference example. Note that, in the transport pick 40b, each component except the configuration of the sensor has the same functional configuration as that of the transport pick 40 described in the above-described embodiment, and therefore, the same reference numerals are given and the description thereof is omitted.

  As shown in FIG. 9, the transport pick 40b according to the reference example 2 includes a transparent type on the upper part of the support plate 42, which is the root of the pick, and on the upper part of the pad member 50, which is located at the tip of the U-shaped pick. A sensor 80 is attached. The transmissive sensor 80 located at the base of the transport pick 40b is the light projecting section 80a, and the transmissive sensor 80 located at the tip is the light receiving section 80b. The light projecting section 80a is more vertical than the light receiving section 80b. It is arranged so that the directional height position is high. When the transfer pick 40b is inserted below the wafer W to be held, the wafer W crosses the irradiation line by the irradiation of the transmissive sensor 80. Thereby, the position data of the outer edge of the wafer is measured.

  Then, similarly to the above-described Reference Example 1, the measurement data when the wafer W is at the specified position is obtained in advance, and the measurement data when the wafer W is at the displaced position is compared, and the difference and the wafer The operation of the transfer pick 40b that can accurately hold the wafer W is realized by calculating and correcting the actual wafer W position from the comparison with the specified position where W is to be arranged. Note that the correction method may be the same as that in Reference Example 1 above.

(Reference example 3)
FIG. 10 is an explanatory diagram relating to the alignment technique of the transport pick 40 and the wafer W according to the reference example 3, and illustrates the movement of the transport pick 40 in time series in the order of (a) to (c).
In the technique according to the third reference example, in the case where the wafer presence/absence detection sensors 60 are attached to the transport pick 40 described above in the third embodiment at three positions on the circumference of the concentric circles S at equal intervals (at intervals of 120° in the circumferential direction). In the above, a transferred object jig (that is, a pseudo wafer) W1 in which holes 90 having a predetermined width are provided at positions (that is, positions on the concentric circle S) corresponding to the installation positions of the wafer presence/absence detection sensors 60 at the three positions. To use.

  First, as shown in FIG. 10A, the transferred object jig W1 is arranged at a predetermined position (for example, a prescribed wafer transfer position). Then, the transport pick 40 is inserted below the transported object jig W1, and the position is such that the wafer presence/absence detection sensor 60 corresponds to all the holes 90 as shown in FIG. 9B. Perform a search operation up to. When the wafer presence/absence detection sensor 60 is, for example, a reflection type sensor, the searching operation is performed until the positions are such that light projection is confirmed for all the hole portions 90. As a result, the specified position of the transfer pick 40 to be inserted to determine whether or not the wafer W is placed at the specified position is determined. That is, the teaching of the wafer transfer device 31 is performed.

Then, as shown in FIG. 10C, the transfer pick 40 is inserted into the specified position of the transfer pick 40 defined above, and at that time, all the wafer presence/absence detection sensors 60 detect the wafer W. In this case, the wafer W is held by the method described in the above embodiment.
According to the alignment technique as described above, it is possible to easily determine the prescribed position of the transport pick 40 (teaching) by using the transported object jig W1 provided with the hole 90.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a transfer method for transferring an object to be transferred, particularly a transfer method for transferring an object to be processed such as a semiconductor wafer, a liquid crystal substrate, and an organic EL element to a processing chamber.

DESCRIPTION OF SYMBOLS 1... Substrate processing system 10... Cassette mounting part 20... Processing chamber 21... Vacuum transfer chamber 31... Wafer transfer device 32... Arm mechanism 37... Joint part 40... Transfer pick 42... Support plate 41... Body part 45... Pad drive part 50... Pad member 60, 70... Wafer presence/absence detection sensor 80... Transmissive sensor 90... Hole W... Wafer (object to be processed)

Claims (3)

A transport method for transporting a transport target in a transport device including a transport pick, comprising:
Inserting the transport pick at a predetermined position below the transport target;
And a step of determining whether or not the transport target is located at a specified position such that the transport pick can hold the transport target at the predetermined position,
The transport pick is provided with transport object presence/absence detection sensors at three or more locations,
The object to be conveyed is circular,
The conveyance object presence/absence detection sensors are arranged at three or more locations on the circumference of a concentric circle having a predetermined diameter on the conveyance pick,
The conveyance object presence/absence detection sensors are arranged at equal intervals in the circumferential direction of the concentric circles,
The concentric circle has a smaller diameter than the outer circumference of the object to be conveyed,
When it is determined by the detection of the conveyance object presence/absence detection sensor that the conveyance object is located at the specified position, the conveyance pick is raised to hold the conveyance object by the conveyance pick,
When it is determined by the detection of the conveyance target presence/absence detection sensor that the conveyance target is not located at the specified position, after the conveyance target is positioned within the specified position by the searching operation of the conveyance pick. A carrying method, characterized in that the carrying pick is raised and the carrying object is held by the carrying pick. The search operation of the transport pick is performed in a direction such that the transport target presence/absence detection sensor that has not detected the transport target among the transport target presence/absence detection sensors provided at the three or more locations detects the transport target. The transport method according to claim 1, wherein the transport pick is performed by moving the transport pick. The transport method according to claim 1, wherein the transport object presence/absence detection sensor is a reflective fiber sensor.

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