JP4627515B2 - Thin plate material transfer device - Google Patents

Description

  The present invention relates to a thin plate material transfer device, and more particularly, to a thin plate material transfer device for storing and taking out thin plate materials such as semiconductor wafers and liquid crystal glass substrates one by one in a storage cassette.

  FIG. 5 shows a first transfer device for transferring a semiconductor wafer as an example of a conventional thin plate material transfer device. FIG. 5A is a perspective view showing a schematic configuration of a conventional first transfer apparatus, and FIG. 5B is an enlarged view of a main part.

  In FIG. 5, 20 is a conventional first transfer device, 21 is a storage cassette, 22 is a groove formed in the side wall of the storage cassette 21, 23 is a wafer, 24 is an arm, and 23a is adjacent to the arm 24 with 2 therebetween. Wafer housed in the upper groove of the two grooves, 23b is the wafer housed in the lower groove of the two adjacent grooves across the arm 24, 25 is the driving means for the arm 24, and 26 is the elevator , A is the distance between the two wafers 23a and 23b, B is the thickness dimension of the arm 24, and C is the gap dimension between the arm 24 and the two wafers 23a and 23b.

  As shown in FIG. 5A, the conventional first transfer device 20 has an arm 24 that holds the wafer 23 on its upper surface and moves forward and backward to the storage cassette 21, and a drive that moves the arm 24 up, down, front, back, left and right. Means 25 and an elevator unit 26 for moving the storage cassette 21 up and down are provided, and the storage cassette 21 can be moved up and down to store and take out the wafers 23 one by one in the predetermined groove 22. ing.

  The storage cassette 21 is open at the front and rear surfaces for loading and unloading the wafers 23. Inside the left and right side walls, grooves 22 for horizontally supporting the wafers 23 one by one are provided at a predetermined pitch. Many pairs are formed.

  In the storing operation of the wafer 23 by the conventional first transfer device 20, first, the arm 24 holding the wafer 23 on the upper surface is stored at a predetermined height with respect to the groove 22 where the wafer 23 is to be stored. It is made to enter the cassette 21 horizontally.

  At this time, the entry height of the arm 24 is normally set to a height that allows a uniform gap between the upper and lower wafers 23.

  Next, when the arm 24 enters the end point of the predetermined entry operation, the operation of the arm 24 is stopped, the elevator unit 26 is operated, and the storage cassette 21 is raised by a predetermined distance. By this operation, the wafer 23 is separated from the upper surface of the arm 24 and supported by the groove 22.

  Then, the empty arm 24 is pulled out from the storage cassette 21 to complete the storage operation.

  Thereafter, the elevator unit 26 is operated to change the height of the storage cassette 21 to a predetermined height for storing the next wafer 23.

  In the above description, the storage cassette 21 is raised and the arm 24 and the wafer 23 are separated from each other. However, the arm 24 may be lowered by the driving means 25 and separated.

  Next, the wafer 23 is taken out in the reverse order of the storing operation.

  That is, first, the empty arm 24 is moved horizontally into the storage cassette 21 at a predetermined height with respect to the groove 22 that supports the wafer 23 to be taken out.

  Next, when the arm 24 enters the end point of the predetermined entry operation, the operation of the arm 24 is stopped, the elevator unit 26 is operated, and the storage cassette 21 is lowered by a predetermined distance. By this operation, the wafer 23 is held on the upper surface of the arm 24.

  Then, the arm 24 holding the wafer 23 is pulled out from the storage cassette 21 to complete the take-out operation.

  Thereafter, the elevator unit 26 is operated to change the height of the storage cassette 21 to a predetermined height for taking out the next wafer 23.

  In the above description, the storage cassette 21 is lowered and the arm 24 holds the wafer 23. However, the arm 24 may be raised and held by the driving unit 25.

  Here, as shown in FIG. 5B, for example, the distance A between the two wafers 23a and 23b is about 6 mm, and the thickness dimension B of the arm 24 is about 2 to 3 mm.

  Therefore, the gaps C between the wafers 23a and 23b immediately above / below when the arm 24 is moved back and forth in the storage cassette 21 are as small as about 1.5 to 2 mm (C = (A−B) / 2). .

  For this reason, when the variation in the vertical movement gradually increases due to the wear of the parts of the elevator section 26 with time, the variation in the entry height of the arm 24 into the storage cassette 21 increases accordingly, and the above gap When entering beyond the portion C, the arms 24 damage the surfaces (lower surface or upper surface) of the wafers 23a and 23b.

  On the other hand, the following conventional second and third transfer apparatuses have been proposed.

  First, a conventional second transfer device will be described with reference to FIG. FIG. 6 is a side sectional view showing a schematic configuration of a conventional second transfer device. The same parts as those in FIG. Further, since the wafer storing / extracting operation is the same as that of the conventional first transfer device 20, a detailed description thereof will be omitted.

  In FIG. 6, 40 is a conventional second transfer device, 41 is an arm, 42 is a sensor, 43 is a contact-type sensor, 44 is a metal layer, 45 is an elastic layer, 46 is an amplifier, and 47 is a controller. , 48 is an elevating mechanism portion of the arm 41, and 49 is a driving means of the arm 41.

  As shown in FIG. 6A, the conventional second transfer apparatus 40 includes a metal arm 41 that holds the wafer 23a on its upper surface, drive means 49 that moves the arm 41 back and forth, and right and left, and an arm 41. , And a sensor 42 that senses contact between the lower surface of the arm 41 and the upper surface of the wafer 23b.

  The sensor 42 includes a contact type sensing unit 43, an amplification unit 46 that amplifies an electrical signal generated by the sensing unit 43, and a control unit 47 that receives the amplified signal and controls the lifting mechanism unit 48. And.

  The sensing unit 43 is configured by attaching a metal layer 44 to the lower surface of the arm 41 via an elastic layer 45 made of silicon rubber.

  Then, as shown in FIG. 6B, when the lower surface of the arm 41 comes into contact with the upper surface of the wafer 23b, the metal layer 44 is pushed up and short-circuited with the lower surface of the arm 41 to generate an electrical signal.

  When the control unit 47 receives this electrical signal via the amplifying unit 46, the control unit 47 stops the arm 41 and then lowers the storage cassette (not shown) by the elevating mechanism unit 48. And the wafer 23b are separated from each other. (For example, refer to Patent Document 1).

  Next, a conventional third transfer device will be described with reference to FIG. FIG. 7 is a side sectional view showing a schematic configuration of a conventional third transfer device. The same parts as those in FIG. Further, since the wafer storing / extracting operation is the same as that of the conventional first transfer device 20, a detailed description thereof will be omitted.

  In FIG. 7, 50 is a conventional third transfer device, 51 is an arm, 52 is a distance sensor, 53 is a controller, 54 is a correction control unit, 55 is a manipulator, 55a is a link, 55b is a joint, and 56 is a base part. is there.

  As shown in FIG. 7, a conventional third transfer apparatus 50 includes an arm 51 that holds a wafer 23a on its upper surface, a robot hand type manipulator 55 that moves the arm 51 up and down, front and rear, and left and right, and this manipulator 55. And a controller 53 to be controlled.

  The manipulator 55 includes a link 55a and a joint 55b that can be driven and controlled, and an arm 51 attached to the tip of the link 55a. The base portion 56 is fixedly installed on the floor, and the arm 51 is placed at an arbitrary position. It is movable.

  The controller 53 drives the manipulator 55 to control the trajectory of the arm 51.

  Further, an optical non-contact distance sensor 52 that measures the distance from the bottom surface of the wafer 23a is disposed on the top surface of the tip of the arm 51.

The distance sensor 52 is connected to a correction control unit 54 built in the controller 53, and performs distance measurement in real time from immediately after the arm 51 enters between the wafers 23a and 23b to the end point of the entry operation. Based on the distance information, the correction control unit 54 corrects the movement path of the arm 51. (For example, refer to Patent Document 2).
JP, 2002-9126, A FIG. JP 2002-136280 A FIG.

  However, since the conventional second and third transfer devices 40 and 50 are configured to attach the sensing unit 43 and the distance sensor 52 protruding in the thickness direction to the arms 41 and 51, the arms 41 and 51 are provided. In the direction of further reducing the narrow gap between the wafer 23a and the wafers 23a and 23b, it was difficult in terms of space. Further, when the thickness of the arms 41 and 51 is reduced for mounting the sensing unit 43 and the distance sensor 52, the mechanical strength of the arms 41 and 51 is lowered.

  Further, in the conventional second transfer device 40, since the contact between the arm 41 and the wafer 23b is detected only after the metal layer 44 is deformed until it contacts the lower surface of the arm 41, the deformation amount of the metal layer 44 is small. In this case, the contact could not be detected.

  When contact is detected, the wafer 23b has already been damaged, and damage to the wafer 23b could not be prevented.

  Further, in the conventional third transfer device 50, the position correction amount is calculated based on the distance information from the distance sensor 52, and the arm 51 is moved while feeding it back to the manipulator 55. The operating speed was expected to be slow.

  The main problem of the present invention is whether or not the arm has entered the storage cassette at a height within a predetermined range without disposing a protrusion in the thickness direction on the arm or slowing down the operating speed of the arm. It is an object of the present invention to provide a transport device for a thin plate material that can reliably detect the damage and prevent the arm from damaging the thin plate material.

The thin plate material conveying apparatus of the present invention is
A movable electrode portion that extends in the forward / backward movement direction of the arm, and has a first electrode exposed at the tip of the arm that holds the thin plate material and moves forward / backward to the storage cassette;
Fixing that the second electrode that is fixed on the side facing the arm across the storage cassette and that can contact the first electrode at the end of the operation of entering the storage cassette of the arm is exposed on the surface facing the arm An electrode part;
The first and second electrodes are electrically connected to each other, and a detection unit that electrically detects whether the first and second electrodes are in a conductive state or a non-conductive state at the end point of the arm entry operation. It is a conveyance apparatus of a thin plate material.

  According to the thin plate material conveying device of the present invention, the arm can be placed in the storage cassette at a height within a predetermined range without disposing a protrusion in the thickness direction on the arm or slowing down the operating speed of the arm. It is possible to reliably detect whether or not it has entered, and to prevent the thin plate material from being damaged by the arm.

  As an example of the thin plate material transfer apparatus of the present invention, a semiconductor wafer transfer apparatus is shown in FIG. FIG. 1 is a side sectional view showing a schematic configuration of a transport apparatus according to the present invention. The same parts as those in FIG.

  In FIG. 1, 100 is a transfer apparatus of the present invention, 21 is a storage cassette, 23 is a wafer, 24 is an arm, 23a is a wafer stored in an upper groove of two adjacent grooves across the arm 24, 23b Is a wafer housed in the lower groove of two adjacent grooves across the arm 24, 25 is a driving means for the arm 24, 26 is an elevator section, 102 is a movable electrode section, 102a is a movable electrode section 102 The first electrode exposed on the front end surface, 103 is a fixed electrode portion, 103a is a second electrode exposed on the surface of the fixed electrode portion 103, 103b is a first insulating substrate, 103c is a second insulating substrate, and 103d is It is a cushion part.

  As shown in FIG. 1, the transfer device 100 of the present invention has an arm 24 that holds a wafer 23 on its upper surface and moves forward and backward to the storage cassette 21, and extends beyond the arm 24 in the forward and backward movement direction of the arm 24. The movable electrode portion 102 with the first electrode 102a as the movable electrode exposed at the tip surface thereof, and the second electrode that can come into contact with the first electrode 102a at the end point of the operation of entering the storage cassette 21 of the arm 24 103a is a large number of fixed electrode portions 103 exposed on the surface facing the arm 24 and vertically exposed; driving means 25 for moving the arm 24 and the movable electrode portion 102 up and down, front and rear, left and right; the storage cassette 21 and the fixed electrode portion 103 is electrically connected to the elevator unit 26 that moves the arm 103 up and down together with the first electrode 102a and the second electrode 103a, respectively, and the end point of the approach operation of the arm 24 is reached. And a detection unit 104 that electrically detects whether the first and second electrodes 102a and 103a are in a conductive state or a non-conductive state. The storage cassette 21 is moved up and down to form a predetermined groove (not shown). 1), the wafers 23 can be stored and taken out one by one.

  The storage cassette 21 is open at the front and rear surfaces for loading and unloading the wafers 23, and a groove (not shown) for horizontally supporting the wafers 23 one by one inside the left and right side walls. ) Are formed in pairs at a predetermined pitch.

  Further, the thickness of the movable electrode portion 102 integrally formed at the tip of the arm 24 is the same as or slightly smaller than the thickness of the arm 24.

  The arm 24 and the movable electrode portion 102 are made of an insulator such as ceramic, and the first electrode 102a is electrically connected to the detection portion 104 through an internal wiring formed by being embedded therein. .

  The fixed electrode portion 103 has a laminated structure in which the first insulating substrate 103b having the second electrode 103a exposed on the surface and the second insulating substrate 103c as a support are bonded to each other with the cushion portion 103d interposed therebetween. It has become.

  The cushion portion 103d may be, for example, an elastic layer made of silicon rubber or the like, or a cushion spring, and serves to relieve stress when the first electrode 102a contacts the second electrode 103a. Anything to do.

  The second electrode 103a is an electrode group having the same number of grooves as that of the storage cassette 21 and vertically arranged at the same pitch as the groove pitch. The individual electrodes of the electrode group are formed on the first insulating substrate 103b. It is electrically connected to the detection unit 104 through an internal wiring formed embedded inside.

  The fixed electrode portion 103 has a height position where each electrode of the electrode group has a one-to-one correspondence with each groove, and an end point of the approach operation of the arm 24, and the first electrode 102a It is fixed at a position in the front-rear direction where it can come into contact with the second electrode 103 a, and is moved up and down together with the storage cassette 21 by the elevator unit 26.

  In addition, the detection unit 104 applies a predetermined weak voltage between the first and second electrodes 102a and 103a, and contacts between the first and second electrodes 102a and 103a at the end point of the approach operation of the arm 24. It can be detected by the magnitude of the current whether it is in a conductive state or non-conductive without contact.

  The detection unit 104 is connected to the driving unit 25 of the arm 24, and can operate the driving unit 25 and control the operation of the arm 24 based on the detection result.

  Next, an example of the relationship between the entry height of the arm 24 and the first and second electrodes 102a and 103a will be described with reference to FIGS. 2 and 3 are enlarged views of main parts.

  For example, as shown in FIG. 2, the vertical dimension (L) of the first electrode 102a and the second electrode 103a is the same dimension, the centers of the first electrode 102a and the second electrode 103a are aligned, and the arm 24 Is set so as to aim at the center between the two wafers 23a and 23b (the gap size on one side is C).

  When the vertical dimension L is set so that the vertical dimension L <the gap dimension C, as shown in FIG. 3A, the arm 24 is within a predetermined range with respect to the storage cassette 21 (incoming height variation). When entering at a height of <vertical dimension L), the first electrode 102a comes into contact with the second electrode 103a at the end point of the approach operation of the arm 24, and the first and second electrodes 102a, 103a are electrically connected. It becomes a state.

  On the other hand, as shown in FIG. 3B, when the arm 24 enters at a height outside the predetermined range (variation in approach height> longitudinal dimension L), the first electrode 102a is the second electrode. The first and second electrodes 102a and 103a are not in contact with each other without being in contact with 103a.

  That is, as the vertical dimension L is reduced with respect to the gap C, the detection sensitivity with respect to the variation in the entry height of the arm 24 is improved.

  As described above, by arbitrarily selecting the vertical dimension L of the electrodes 102a and 103a with respect to the gap C, the variation in the entrance height of the arm 24 is increased before it increases to a level at which the wafers 23a and 23b are damaged. Can be detected.

  Here, since the two electrodes 102a and 103a are not in contact with each other when they are deviated from each other by the dimension L, the vertical dimension L may be determined based on the maximum allowable deviation range of the arm 24 as a guide.

  As an example, the maximum value of the allowable range of deviation of the arm 24 may be set as the vertical dimension L.

  In the above description, the vertical dimension L of the two electrodes 102a and 103a has been described as being the same dimension. However, the dimension is not necessarily the same, and in that case, the larger dimension of the two vertical dimensions is not necessary. May be determined using the maximum value of the allowable range of deviation of the arm 24 as a guide.

  In the storing operation of the wafer 23 by the transfer apparatus 100 of the present invention, first, the arm 24 holding the wafer 23a on the upper surface is set at a predetermined height with respect to a groove (not shown) where the wafer 23a is to be stored. It is made to enter horizontally into the storage cassette 21.

  Next, when the arm 24 enters the end point of the predetermined entry operation, the operation of the arm 24 is stopped.

  At this time, the detection unit 104 detects whether the first and second electrodes 102a and 103a are in a conductive state or in a non-conductive state.

  If the detection unit 104 detects the conduction state between the first and second electrodes 102a and 103a and confirms that the arm 24 has entered at a height within a predetermined range, the elevator unit 26 is operated. The storage cassette 21 is raised by a predetermined distance. By this operation, the wafer 23a is separated from the upper surface of the arm 24 and supported by a groove (not shown).

  Next, the empty arm 24 is pulled out of the storage cassette 21 to complete the storage operation.

  Thereafter, the elevator unit 26 is operated to change the height of the storage cassette 21 to a predetermined height for storing the next wafer 23.

  If the detection unit 104 detects that the first and second electrodes 102a and 103a are in a non-conductive state, the detection unit 104 transmits the signal to the driving unit 25 and stops the operation of the arm 24. Immediately notify the operator of the abnormality by sounding an alarm, etc.

  The operator investigates the cause of the abnormal alarm and takes measures such as replacing worn parts.

  In the above description, the storage cassette 21 is raised and the arm 24 and the wafer 23 are separated from each other. However, the arm 24 may be lowered by the driving means 25 and separated.

  Next, the wafer 23a is taken out in the reverse order of the storing operation.

  That is, first, the empty arm 24 is horizontally moved into the storage cassette 21 at a predetermined height with respect to a groove (not shown) for supporting the wafer 23a to be taken out.

  Next, when the arm 24 enters the end point of the predetermined entry operation, the operation of the arm 24 is stopped.

  At this time, the detection unit 104 detects whether the first and second electrodes 102a and 103a are in a conductive state or in a non-conductive state.

  If the detection unit 104 detects the conduction state between the first and second electrodes 102a and 103a and confirms that the arm 24 has entered at a height within a predetermined range, the elevator unit 26 is operated. The storage cassette 21 is lowered by a predetermined distance. By this operation, the wafer 23 a is held on the upper surface of the arm 24.

  Then, the arm 24 holding the wafer 23 is pulled out from the storage cassette 21 to complete the take-out operation.

  Thereafter, the elevator unit 26 is operated to change the height of the storage cassette 21 to a predetermined height for taking out the next wafer 23.

  If the detection unit 104 detects that the first and second electrodes 102a and 103a are in a non-conductive state, the detection unit 104 transmits the signal to the driving unit 25 and stops the operation of the arm 24. Immediately inform the operator of the abnormality by sounding an alarm.

  The operator investigates the cause of the abnormal alarm and takes measures such as replacing worn parts.

  In the above description, the storage cassette 21 is lowered and the arm 24 holds the wafer 23. However, the arm 24 may be raised and held by the driving unit 25.

  In the above example, the movable electrode portion 102 is provided at one position of the arm 24, and the fixed electrode portion 103 and the detection portion 104 corresponding to the movable electrode portion 102 are arranged to form one detection circuit. As another example of the invention, as shown in FIG. 7, two movable electrode portions 102 are provided apart from both left and right ends (two places) of the arm 24, and a fixed electrode portion 103 and a detection portion 104 corresponding to each are provided. The two detection circuits may be formed independently.

  This is preferable because it can detect variations in the level of the arm 24.

  In the above example, the example of the semiconductor wafer transfer device has been described. However, the present invention can also be used for a transfer device of a thin plate material such as a liquid crystal glass substrate.

  In the above example, the thin cassette was stored in the storage cassette in the horizontal direction. However, the present invention is not limited to the horizontal direction, and can be applied to a configuration in which the thin plate material is stored in the vertical direction or the oblique direction. .

  The present invention reliably detects whether or not the arm has entered the storage cassette at a height within a predetermined range without disposing a protrusion in the thickness direction on the arm or slowing down the operating speed of the arm. It can be applied to a thin plate material transfer device that can prevent the thin plate material from being damaged by the arm.

Side sectional view which shows schematic structure of the conveying apparatus of this invention The principal part enlarged view of the conveying apparatus of this invention The principal part enlarged view of the conveying apparatus of this invention The schematic block diagram of the other example of the conveying apparatus of this invention The perspective view and principal part enlarged view which show schematic structure of the conventional 1st conveying apparatus. Side sectional view which shows schematic structure of the conventional 2nd conveying apparatus. Side sectional view which shows schematic structure of the conventional 3rd conveying apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 Conventional 1st conveying apparatus 21 Storage cassette 22 Groove | channel formed in the side wall of storage cassette 21 Wafer 24,41,51 Arm Arm 23a It accommodates in the upper groove | channel of two adjacent grooves on both sides of the arm 24 Wafer 23b Wafer housed in lower groove of two adjacent grooves across arm 24 25 Driving means for arm 24 26 Elevator section 40 Conventional second transfer device 42 Sensor 43 Contact type Sensing unit 44 Metal layer 45 Elastic layer 46 Amplifying unit 47 Control unit 48 Lifting mechanism unit 49 Driving means of arm 41 50 Conventional third transport device 52 Distance sensor 53 Controller 54 Correction control unit 55 Manipulator 55a Link 55b Joint 56 Root portion 100 Semiconductor wafer transfer device of the present invention 102 Movable electrode portion 102 First electrode 103 Electrode portion 103a Second electrode 103b First insulating substrate 103c Second insulating substrate 103d Cushion portion A Distance between two wafers 23a and 23b B Thickness dimension of arm 24 C Arms 24 and 2 Dimension of gap between each wafer 23a and 23b L Vertical dimension of first and second poles 102a and 103a

Claims (8)

A movable electrode portion that extends in the forward / backward movement direction of the arm and has a first electrode exposed at the tip of the arm that holds the thin plate and moves forward / backward to the storage cassette;
A second electrode fixed on the side facing the arm across the storage cassette and capable of contacting the first electrode at the end point of the arm entering the storage cassette is opposed to the arm. A fixed electrode portion exposed on the surface to be
A detector that is electrically connected to each of the first and second electrodes, and that electrically detects whether the first and second electrodes are in a conductive state or a non-conductive state at an end point of an approach operation of the arm; A thin plate material conveying apparatus.   The second electrode of the fixed electrode portion is in a position corresponding to each of a plurality of grooves provided at a predetermined pitch to support the thin plate inside the left and right side walls of the storage cassette. The apparatus for transporting a thin plate material according to claim 1, which is an array of electrodes.   3. The thin plate material transfer device according to claim 1, wherein a thickness of the movable electrode portion is equal to or less than a thickness of the arm. The thin plate material conveying apparatus according to claim 1, wherein the movable electrode portion is integrally formed with the arm.   The two movable electrode portions are spaced apart from the left and right ends of the arm, and the fixed electrode portion and the detection portion are arranged corresponding to each of the movable electrode portions, and two detection circuits are provided. The thin plate material conveying device according to any one of claims 1 to 4, wherein the thin plate material conveying device is formed.   Each of the first and second electrodes has a size and mutual positional relationship such that when the arm enters the storage cassette at a height within a predetermined range, the first and second electrodes reach the end point of the arm entry operation. When the first electrode contacts the second electrode and becomes conductive, and the arm enters at a height outside a predetermined range, the first electrode does not contact the second electrode and becomes non-conductive. The conveying apparatus of the thin plate material in any one of Claim 1 to 5 set so that it might become.   The thin plate material conveying device according to any one of claims 1 to 6, wherein the fixed electrode portion includes a cushion portion made of an elastic material that relieves an impact at the time of contact between the first electrode and the second electrode. . The thin plate material conveying device according to claim 1, wherein the detection unit is electrically connected to a driving unit that drives the arm.

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