JP4552222B2 - Wafer aligner - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wafer aligner suitable for detecting notches or orientation flats of a large wafer.
[0002]
[Prior art]
As is well known, silicon wafers have a chord-shaped orientation flat, a V-shaped or U-shaped notch or orientation flat, etc. as a mark indicating the reference rotational position in the circumferential direction of the wafer. It is formed in the part. When performing processing such as semiconductor gate formation on the wafer, each wafer is set on the processing stage under a state where the orientation flat or notch or orientation flat always coincides with the reference rotation position. Was requested.
[0003]
A cassette usually stores a plurality of wafers arranged in a vertical direction in a random state. For this reason, removing the wafer from the cassette by the transfer robot and setting it directly on the processing stage means that the wafer is placed on the processing stage in a state where the orientation flat or notch position does not coincide with the reference rotation position. However, the desired processing could not be performed.
[0004]
Therefore, the wafer taken out from the cassette is carried into the orientation flat aligner or wafer aligner, and the position of the notch or orientation flat is matched with the rotation reference by the orientation flat aligner or wafer aligner, and then the wafer is placed on the processing stage. The method of setting was taken.
[0005]
Conventional wafer aligner devices are configured to support the wafer so that it is attracted to the back surface of the wafer, or to drop the wafer and support the outer peripheral surface of the back surface of the wafer. For example, in the case of the wafer aligner 50 shown in FIG. 13, a fixed stage 51 formed with a receiving portion 52 a that supports the outer peripheral surface of the wafer 3, and a rotation that can be moved up and down and rotated below the fixed stage 51. The stage 53 is disposed on the machine base 55 (see Japanese Patent Application Laid-Open No. 2000-21956).
[0006]
The fixed stage 51 has three arms 52 extending at equal intervals with respect to the rotation center position, and the wafer 3 held by the robot hand is moved to a position above the receiving portion 52a by the downward movement of the hand. The rotary stage 53 has three arms 54 extending at equal intervals with reference to the rotation center position, and lifts the wafer 3 supported by the fixed stage 51. After that, the position of the notch or orientation flat can be detected by one rotation.
[0007]
[Problems to be solved by the invention]
However, as in the prior art, when the back surface of the wafer is sucked and supported, the back surface of the wafer is scratched or particles are attached, so that the method of sucking the back surface of the wafer tends to be avoided. The wafer aligner 50 shown in the above publication supports the outer peripheral surface of the back surface of the wafer 3 to damage the wafer 3 and reduce the generation of particles as much as possible. The outer peripheral surface of the wafer 3 is not held so as to be pressed by the guide portion. Therefore, when the wafer 3 is rotated to detect the position of the notch or orientation flat, slippage occurs between the outer peripheral surface of the wafer 3, the arm 54 of the rotary stage 53, and the wafer receiver 54a, thereby ensuring the accuracy in the rotation direction. I couldn't. For this reason, in order to ensure accuracy, it is necessary to drive at a speed that does not slip, and high-speed rotation is limited. Further, since there is a slight gap between the outer peripheral surface of the wafer 3 and the guide portion 54b of the arm 54, the positioning accuracy is lowered not only in the rotation direction but also in the X-axis and Y-axis directions.
[0008]
Further, since the wafer 3 on which the position of the notch or orientation flat is detected is placed on the fixed stage 51, the process waits until the hand is loaded for each wafer, thereby increasing the waiting time and lowering the throughput. I was letting.
[0009]
The present invention solves the above-mentioned problems, and improves the positioning accuracy by reliably grasping the edge of the wafer without damaging the wafer or generating particles, and the position of the notch or orientation flat at high speed. An object of the present invention is to provide a wafer aligner that can detect and improve the throughput.
[0010]
[Means for Solving the Problems]
The wafer aligner according to the present invention is configured as follows in order to solve the above-mentioned problems. That is,
A holding means that is rotatably arranged to hold the wafer, a delivery means that holds the wafer transferred from the robot and delivers it to the holding means, and a detection means that detects a notch or orientation flat position during rotation of the wafer A wafer aligner configured to match a notch or orientation flat position of the wafer with a reference rotational position,
The delivery unit includes the wafer holding unit in two stages, is configured to be rotatable by a predetermined angle by the first rotation driving unit, and can move the holding unit up and down between the upper side and the lower side of the wafer holding unit. The first opening / closing driving means is configured to be openable and closable,
The holding means has a wafer gripping portion that can be raised and lowered with a wafer holding portion of the delivery means interposed therebetween, and is configured to be rotatable by second rotation driving means, and the delivery means by the raising and lowering driving means. It is configured to be movable from a lower position to an upper position with the wafer holding position in between, and to be opened and closed by a second opening / closing drive means for gripping or releasing the edge of the wafer. It is characterized by.
[0011]
Preferably, the first rotation driving unit may be configured to be rotatable by a shift angle for avoiding an overlap between the holding unit and the delivery unit.
[0012]
Further, it is more preferable that the first rotation driving means includes an eccentric cam and a swing lever having a cam roller engageable with the eccentric cam.
[0013]
The delivery means includes at least two wafer holding arms, and the wafer holding arms include first cam means and first roller means engageable with the first cam means. What is necessary is just to be comprised in the direction which approaches / separates with respect to an axial center by a means.
[0014]
The holding means has a plurality of clamp arms arranged in the radial direction from the center of rotation, and each clamp arm has a holding part for holding the edge of the wafer, and at least one clamp arm. However, it is desirable that the second opening / closing drive means is configured to be movable in the horizontal direction.
[0015]
Further, the second opening / closing drive means has a second cam means having a cam portion formed in a vertical direction, and a second roller arranged to be engageable with the second cam means and movable along the cam portion. It is even better if it is configured with means.
[0016]
【The invention's effect】
According to the wafer aligner of the present invention, when a wafer transferred by a robot hand is gripped by a delivery means configured to be openable and closable, the holding means that can be opened and closed is lifted and lowered to grip the wafer. The edge of the wafer is held by the portion, and the wafer gripping portion of the holding means moves up beyond the wafer holding portion of the delivery means, thereby moving the wafer to a rotatable position and then rotating the wafer once. By gripping and rotating the wafer, the notch or orientation flat position of the wafer is detected by the detecting means, and the notch or orientation flat position is adjusted to the reference rotational position. Therefore, since the wafer edge is gripped and rotated, the wafer can be rotated without causing a deviation of the wafer, and the positioning accuracy can be improved reliably and high-speed rotation can be achieved.
[0017]
Further, since the delivery means has a two-stage wafer holding section, one wafer holding section (for example, the upper wafer holding section) can be configured as a buffer stage, and a wafer whose notch or orientation flat position is detected can be buffered. By making the stage stand by, the position of the wafer notch or orientation flat can be continuously detected, and the throughput can be improved.
[0018]
Furthermore, since the back surface of the wafer is not attracted and held, particles are not attached.
[0019]
When the holding means that moves up and down is in a position that overlaps with the delivery means, that is, when the wafer gripping portion of the holding means and the wafer holding portion of the delivery means are at the same angle, the holding means Since the wafer gripping part moves up and down and interferes with the wafer holding part of the delivery means, the first rotation driving means moves to the delivery means by a predetermined angle to avoid overlap, and the wafer of the holding means The holding means can be raised and lowered to hold the wafer on the delivery means at a position where the gripper and the wafer holding part of the delivery means do not interfere with each other.
[0020]
At this time, since the first rotation driving means includes a swing lever having an eccentric cam and a cam roller, the swing lever can be swung by a predetermined angle by the eccentric cam. By swinging the angle, interference between the holding means and the delivery means can be avoided, and overlap can be avoided with an easy configuration.
[0021]
Further, when the wafer whose position of the notch or orientation flat is detected is transferred to the upper buffer stage while being held by the holding means, the first cam means and the first roller means are used as the delivery means, and the two wafers are transferred. Since the holding arm is configured to open and close, the wafer gripping portion of the holding means can be raised and lowered without interfering with the wafer holding portion of the delivery means.
[0022]
In addition, since the holding means has a plurality of clamp arms and one clamp arm can move in the horizontal direction, the holding means opens larger than the outer diameter of the wafer and can be moved to a position where the wafer can be held for delivery. And by further closing, the edge of the wafer can be securely gripped.
[0023]
In addition, since the second opening / closing drive means has the first cam means formed in the vertical direction and the first roller means movable along the first cam means, the holding means can be opened and closed at the same time. As a result, the holding means can move to the height position of the wafer and grip the edge of the wafer. Moreover, since the cam means is formed in the vertical direction, it is possible to provide an aligner device that is compactly configured with a small space in the lateral direction.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The wafer aligner apparatus (hereinafter referred to as aligner apparatus) of the present invention has a notch or orientation flat formed on the wafer in a state where the positional accuracy is improved by gripping the edge of the wafer transferred by the robot hand. Is detected and aligned with the reference rotational position.
[0025]
As shown in FIGS. 1 and 2, the aligner apparatus 1 according to the embodiment includes a machine base 10, a delivery arm unit 20 as a delivery unit that temporarily supports the wafer 3 transferred by the robot hand 5, and a delivery arm unit. A holding clamper 30 as a holding means configured to be rotatable to hold the wafer 3 supported by 20 and detect the position of the notch or orientation flat, and protrudes upward from one end of the machine base 10. At the same time, it includes a detection unit 40 as detection means for detecting the position of the notch or orientation flat of the wafer 3 held and rotated by the holding clamper 30.
[0026]
The machine base 10 is formed in a casing shape, and a central rotating shaft 11 that is fixed to the bottom of the machine base 10 and protrudes from the bottom to the machine base 10 is provided at the center, and is delivered to the machine base 10. The arm part 20 and the holding clamper 30 are arranged so as to protrude.
[0027]
As shown in FIG. 3, the machine base 10 includes an opening / closing drive unit 12 that opens and closes the delivery arm unit 20, a shift angle rotation drive unit 13 that rotates the delivery arm unit 20 by a predetermined angle with respect to the axis, and a holding clamper. The rotary drive unit 14 that rotationally drives 30, the lift drive unit 15 that lifts and lowers the holding clamper 30, and the open / close drive unit 16 that drives the holding clamper 30 to open and close are incorporated.
[0028]
The delivery arm portion 20 protrudes above the machine base 10 and is rotatably supported via a bearing 24. The delivery arm portion 20 is mounted on the rotation shaft portion 21 and extends symmetrically. L-shaped lower arm portions 22 and 23, and a lower nail having a wafer 3 placed on the upper ends of the lower arm portions 22 and 23 and having two wafer receiving portions 221a and 231a, respectively. 221 and 231 and upper claw portions 222 and 232 having wafer receiving portions 222 a and 232 a formed as buffer stages of the wafer 3 are arranged, and one swing lever 25 is provided on the lower end surface of the rotating shaft portion 21. A cam roller 26 (see FIG. 4) is disposed at the tip. Further, as shown in FIG. 5, the lower arm portions 22 and 23 are respectively supported by a pair of cam rollers 28 and 28 that engage with a cam member 27 fitted inside the rotary shaft portion 21. Along with the movement, it is linearly moved in a direction approaching and separating from the center of the cam member 27 (rotation center shaft portion 11).
[0029]
As shown in FIGS. 2 and 3, the holding clamper 30 includes a cylindrical shaft portion 31 that covers the rotation center shaft portion 11 and is rotatably disposed on the rotation center shaft portion 11, and an upper end portion of the cylindrical shaft portion 31. It has three upper arm portions 33, 34, and 35 that extend from a head 32 that is formed and extends radially in three directions. The three upper arm portions 33, 34, and 35 are respectively provided with claw portions 331, 341, and 351 that hold the wafer 3 at the top end portion, and one of the upper arm portions 33 is located with respect to the rotation center shaft portion 11. Are arranged so as to approach and separate in the horizontal direction.
[0030]
That is, the upper arm portion 33 is attached to the head portion 32 so as to be movable via the linear guide 36, and the other two upper arm portions 34 and 35 are formed integrally with the head portion 32 or are screws or the like. It is fixed by. The base part of the movable upper arm part 33 is inserted into a notch groove 311 formed in one of the upper end parts of the cylindrical shaft part 31 and is provided with a cam roller 332 at the lower end part. The upper arm 33 is always urged toward the head 32 by being hooked.
[0031]
As shown in FIG. 3 or 5, the opening / closing drive unit 12 that opens and closes the delivery arm unit 20 includes an upper claw unit 222 that uses the wafer 3 held by the upper arm units 33, 34, and 35 of the holding clamper 30 as a buffer stage. 223, which is opened and closed to avoid interference between the wafer 3 and the upper claw portions 222 and 232 when being moved up and down, and engages the symmetrical position of the cam member 27 and the cam member 27 described above. A motor 121 having a pair of cam rollers and rotationally driving the cam member 27, a small gear 122 mounted on the drive shaft of the motor 121, and a large gear engaged with the small gear and mounted on the lower portion of the cam member 27 And a gear 123. As shown in FIG. 5, the cam shape of the cam member 27 includes a pair of convex portions 271 and a pair of concave portions 272 that are formed symmetrically with respect to the axial center. The stroke difference cam roller 28 in the straight line shape is moved, and accordingly, the lower arm portions 22 and 23 are moved.
[0032]
The shift angle rotation drive unit 13 that rotates the delivery arm unit 20 by a predetermined angle detects the notch or orientation flat position of the wafer 3 and then moves the upper arm units 33 and 34 in the holding clamper 30 when the holding clamper 30 moves to the reference rotation position. In order to avoid interference when the claw portions 331, 341, 351 of the 35 are set at positions where they interfere with the lower claw portions 221, 231 of the lower arm portions 22, 23 in the delivery arm portion 20 3 to 4, the motor 131 supported in the machine base 10, the eccentric cam 132 mounted on the drive shaft of the motor 131, and one end of the swing lever 25 are provided. The cam roller 25 is mounted and can be engaged with the outer peripheral surface of the eccentric cam 132.
[0033]
Accordingly, when the eccentric cam 132 is rotated by driving the motor 131, the cam roller 132 engaged with the eccentric cam 132 is moved. Since the other end of the cam roller 132 is mounted on one end of the swinging lever 25 that is fixed to the rotating shaft portion 21, the swinging lever 25 swings with respect to the center of rotation, thereby rotating the rotating shaft portion 21 into the rotating shaft portion. It rotates by a predetermined angle with respect to the center of 21. This angle indicates an avoidance angle when the delivery arm portion 20 and the holding clamper 30 overlap, and is desirably set to 5 to 7 °.
[0034]
As shown in FIG. 3, the rotation drive unit 14 that rotates the holding clamper 30 includes a motor 141 supported in the machine base 10, a small pulley 142 attached to a drive shaft of the motor 141, and a belt 143. And a large pulley 144 fixed integrally with the cylindrical shaft portion 31. Therefore, when the motor 141 is driven to rotate, the large pulley 144 is rotated from the small pulley 142 via the belt 143, so that the cylindrical shaft portion 31 fixed to the large pulley 144 rotates around the rotation center shaft portion 11. It will be.
[0035]
The raising / lowering drive unit 15 for driving raising / lowering of the holding clamper 30 is connected to the motor 151 supported in the machine base 10, the driving pulley 152 mounted on the driving shaft of the motor 151, and the driving pulley 152 via the belt 153. Driven pulley 154, a ball screw 155 supported in the machine base 10 and rotatable with the rotation of the driven pulley 154, a nut member 156 screwed into the ball screw 155 and movable up and down, and one end of the nut member 156 And an elevating plate 158 that is supported by a cylindrical shaft portion 31 via a bearing 157. The elevating plate 158 and the cylindrical shaft portion 31 are configured to move up and down integrally. Therefore, when the motor 151 is driven to rotate, the ball screw 155 is rotated via the drive pulley 152 and the driven pulley 154, and the nut member 156 is moved up and down accordingly, whereby the cylindrical shaft portion 31 is moved up and down, and the upper arm portion 33, 34 and 35 are moved up and down.
[0036]
The opening / closing drive unit 16 that drives opening and closing of the holding clamper 30 is provided above the rotation center shaft portion 11, above the lower large diameter portion 111 a, the small diameter portion 111 b located above the lower large diameter portion 111 a, and above the small diameter portion 111 b. The cam surface 111 is formed in the vertical direction with the upper large diameter portion 111c positioned, and the cam roller 332 of the upper arm portion 33 that engages with the cam surface 111, and the lift drive unit 15 is configured as a drive source. The
[0037]
In other words, when the upper arm portion 33 is moved up and down by moving the cylindrical shaft portion 31 up and down by the drive of the lift drive unit 15, the cam roller 332 is moved up and down simultaneously with the movement of the upper arm portion 33. Since the cam roller 332 moves up and down in the vertical direction along the cam surface 111, the upper arm portion 33 moves in a direction away from the rotation center shaft portion 11 when engaging the lower large diameter portion 111 a of the cam surface 111. When the cam roller 332 engages with the small diameter portion 111b, the cam roller 332 moves in a direction approaching the rotation center shaft portion 11, and when the cam roller 332 further rises and engages with the upper large diameter portion 111c, the cam roller 332 moves away from the rotation center shaft portion 11. The opening / closing drive is performed by moving.
[0038]
As shown in FIG. 1, the detection unit 40 that detects the notch or orientation flat position of the wafer 3 passes through the outside of the upper arm unit 33 from one end of the side of the machine base 10, and the upper ends of the upper arm unit 33 and the lower arm unit 22. A U-shaped bracket 41 disposed so as to be positioned above; a position detection sensor 44 for mounting a pair of light projecting unit 42 and light receiving unit 43 on the upper and lower sides of the wafer 3 in the bracket 41; and a buffer stage A wafer presence / absence sensor 47 including a light projecting unit 45 and a light receiving unit 46 is confirmed. The light projecting unit 42 and the light receiving unit 43 are respectively disposed in the bracket 41 at positions where the light projecting unit 42 of the position detection sensor 44 can emit light toward the edge of the lower wafer 3. The light projecting unit 45 and the light receiving unit 46 are disposed in the bracket 41 at positions where the light projecting unit 45 can emit light toward the edge of the upper wafer 3.
[0039]
Next, the operation of the aligner apparatus 1 configured as described above will be described with reference to FIGS.
[0040]
Loading and unloading of the wafer 3 with respect to the wafer aligner device 1 of the embodiment is performed by the hand 5 of the transfer robot, and the hand 5 is moved in and out from the direction orthogonal to the longitudinal direction of the delivery arm unit 20 in FIG. become. The hand 5 lowers and places the wafer 3 on the wafer receiving portions 221a and 231a of the lower claw portions 221 and 231 from above the lower claw portions 221 and 231 of the delivery arm portion 20, thereby aligning the wafer 3 on the aligner. It will be transferred onto the device 1. Then, after the wafer 3 is loaded onto the aligner device 1, the hand 5 moves from the aligner device 1 to the robot side (not shown). In this state, the upper arm portions 33, 34, and 35 are at the height positions shown in FIG. 3, and the cam roller 332 is positioned below the large-diameter portion 111 a of the cam surface 111 formed on the rotation center shaft portion 11. .
[0041]
When the wafer 3 is placed on the delivery arm portion 20, the lifting / lowering driving portion 15 of the holding clamper 30 is activated, and the cylindrical shaft portion 31 is moved along with the nut member 156 and the lifting plate 158 that are screwed into the ball screw 155. Raise. Accordingly, as shown in FIG. 6, the cam roller 332 rises toward the large diameter portion 111 a of the cam surface 111. Then, the upper arm portion 33 moves in a direction away from the rotation center shaft portion 11 and moves the claw portion 331 outward from the edge of the wafer 3 while raising the claw portion 331 to the height position of the edge of the wafer 3. To do. The other upper arms 34 and 35 are raised to the same height position without opening and closing.
[0042]
Further, when the elevating drive unit 15 is actuated to raise the cam roller 332 together with the cylindrical shaft portion 31, the cam roller 332 reaches the small diameter portion 111b of the cam surface 111 and the upper arm portions 33, 34, 35 as shown in FIG. Is moved to a position above the lower claw portions 221 and 231 of the delivery arm portion 20, and the upper arm portion 33 is moved closer to the rotation center shaft portion 11 side by the urging force of the coil spring 333, and the edge of the wafer 3 is moved to the other upper arm portion. The edge of the wafer 3 is held at three points by being brought into contact with the 34 and 35 sides.
[0043]
The height position of the wafer 3 coincides with the position of the wafer 3 arranged below among the wafers indicated by the two-dot chain line in FIG. 1, and then the holding clamper 30 is rotated once at this height position. Let
[0044]
The drive motor 141 of the rotational drive unit 14 that rotationally drives the holding clamper 30 is actuated to rotate the cylindrical shaft portion 31 once as shown by the arrow in FIG. The wafer 3 held by the claw portions 331, 341, 351 of the upper arm portions 33, 34, 35 rotates once with respect to the machine base 10 with one rotation of the cylindrical shaft portion 31. In the detection unit, the position detection sensor 44 of the detection unit 40 emits light from the light projecting unit 42 toward the light receiving unit 43 toward the edge of the wafer 3 simultaneously with the rotation of the wafer 3, thereby The orientation flat position is detected, and the wafer presence / absence sensor 47 detects the presence / absence of the wafer 3 held by the upper claw portions 222 and 232 by emitting light from the light projecting portion 45 toward the light receiving portion 46.
[0045]
The wafer 3 from which the position of the notch or orientation flat is detected has a predetermined angle by the motor 141 calculated and driven by a control device (not shown) from a position rotated once so that the notch or orientation flat position coincides with the rotation reference position. Rotate to adjust the notch or orientation flat position to the reference rotation position.
[0046]
Next, the aligned wafer 3 is further raised and transferred to the buffer stage as shown in FIGS. That is, the ball screw 155 is rotated by the operation of the motor 151 of the elevating drive unit 15, and the cam roller 332 is raised along with the rise of the cylindrical shaft portion 31 due to the rise of the nut member 156 and the elevating plate 158, so Engage with the portion 111c. When the cam roller 332 is engaged with the upper large-diameter portion 111c, the upper arm portions 33, 34, and 35 of the holding clamper 30 move to a position slightly raised from the upper claw portions 222 and 232 of the delivery arm portion 20, and the upper arm Since the portion 33 is separated from the rotation center shaft portion 11, the holding clamper 30 is opened larger than the outer diameter of the wafer 3. However, since the wafer 3 is held on the bottom surface of the claw portion 331 of the upper arm portion 33, it does not fall off from the holding clamper 30.
[0047]
When the holding clamper 30 is raised, the lower arm portions 22 and 23 of the delivery arm unit 20 are opened by the opening / closing drive unit 12 in order to avoid interference with the wafer 3 or the delivery arm unit 20. This action is achieved by operating the motor 121 and rotating the cam member 27 to engage the pair of cam rollers 28 and 28 with the convex portions 271 and 271 from the concave portions 272 and 272 of the cam member 27 as shown in FIG. Thus, the lower arm portions 22 and 23 are moved away from the rotation center shaft portion 11.
[0048]
When the wafer 3 moves above the upper claw portions 222 and 232 of the delivery arm portion 20, the cam member 27 is further rotated to move the pair of cam rollers 28 and 28 from the convex portions 271 and 271 of the cam member 27 to the concave portions 272 and 272. 272 is engaged and moved. As a result, as shown in FIG. 9, the upper claw portions 222 and 232 of the lower arm portions 22 and 23 are moved closer to the rotation center shaft portion 11 and moved to positions where the wafer 3 can be held.
[0049]
When the holding clamper 30 is lowered in this state, the holding clamper 30 is in an open state (the upper arm portion 33 is moved outward from the outer diameter of the wafer 3), as shown in FIG. The wafer 3 is transferred onto the upper claw portions 222 and 232 of the delivery arm portion 20 and stored in the buffer stage. The holding clamper 30 is further lowered to position the claw portions 331, 341, 351 of the upper arms 33, 34, 35 below the lower claw portions 221, 231 of the delivery arm portion 20.
[0050]
When the holding clamper 30 is lowered, if any of the claw portions 331, 341, 351 (claw portion 351 in the illustrated example) of the upper arms 33, 34, 35 of the holding clamper 30 is delivered as shown in FIG. If the lower arm 22 or 23 of the lower arm 22 or 23 of the arm 20 is overlapped with the lower pawls 221 and 231 (the lower pawl 231 in the illustrated example), the holding clamper 30 cannot be lowered due to interference with the delivery arm 20. 3-4, the delivery arm portion 20 is positioned at a predetermined angle so as not to interfere with the lower claw portions 221 and 231 of the lower arm portion 22 or 23 and the claw portions 331, 341 and 351 of the upper arm portion 33 or 34 or 35. Rotate.
[0051]
This operation is performed by the shift angle rotation driving unit 13 of the delivery arm unit 20. That is, when the motor 131 is operated, the eccentric cam 132 rotates and the cam roller 26 is moved by the eccentric stroke of the eccentric cam 132, and the swing lever 25 to which the cam roller 26 is attached is as shown in FIG. Oscillating with respect to the rotation center and rotating the rotary shaft portion 21 by 5 to 7 °, so that the lower arm portions 221, 231 of the lower arm portion 22 or 23 and the claw portion 331 of the upper arm portion 33 or 34 or 35, Thus, overlap with 341 and 351 is avoided.
[0052]
When the overlap between the delivery arm unit 20 and the holding clamper 30 is avoided, the holding clamper 30 is lowered and waiting for the next wafer 3 to be carried in by the hand 5.
[0053]
When the next wafer 3 is carried in by the hand 5 and transferred onto the lower claw portions 221 and 231 of the delivery arm unit 20, the hand 5 is moved back to the robot side again, and the lower claw portion is operated as described above. The wafer 3 held by 221 and 231 is aligned. That is, in this state, the wafer 3 that has been aligned with the buffer stage is waiting, and the next wafer 3 can be held by the holding clamper 30 to align the notch or orientation flat of the wafer 3. .
[0054]
Then, when the next wafer 3 that has been aligned is transferred from the holding clamper 30 to the lower claw portions 221 and 231 of the delivery arm portion 20, the hand 5 is carried in, and the upper claw portion 222 of the delivery arm portion 20; A wafer (wafer on the buffer stage) 3 waiting on 232 and the wafer transferred onto the lower claw portions 221 and 231 are sequentially carried out. Then, a new wafer is loaded again and the wafer is newly aligned. This completes one cycle.
[0055]
When carrying out the upper and lower two wafers for which the hand 5 has completed the alignment, for example, if a robot having a hand arranged in two stages is installed, two wafers can be carried out at the same time. Throughput can be further improved.
[0056]
As described above, the aligner device 1 of the embodiment grips and rotates the edge of the wafer 3, and therefore can rotate without causing the wafer 3 to be displaced, thereby reliably improving positioning accuracy and high speed. Rotation can be possible.
[0057]
Moreover, since the delivery arm part 20 has two claw parts (lower claw parts 221 and 231 and upper claw parts 222 and 232), one claw part (for example, the upper claw parts 222 and 232) is provided. It can be configured as a buffer stage, and the position detection operation of the notch or orientation flat of the wafer 3 can be continuously performed in a state where the wafer 3 that has detected the position of the notch or orientation flat is kept in the buffer stage, thereby improving the throughput. .
[0058]
Furthermore, since the back surface of the wafer 3 is not attracted and held, particles are not attached.
[0059]
Further, when the holding clamper 30 configured to be able to move up and down is in a position overlapping the delivery arm portion 20, that is, any one of the claw portions 331, 341, 351 of the holding clamper 30 and the lower claw of the delivery arm portion 20. When one of the portions 221 and 231 is at the same angle, the claw portions 331, 341, and 351 of the holding clamper 30 interfere with the lower claw portions 221 and 231 of the delivery arm portion 20 by moving up and down. Therefore, the rotation drive unit 13 is moved by a predetermined angle with respect to the delivery arm unit 20 to avoid overlap, and the claw portions 331, 341, 351 of the holding clamper 30 and the lower claw of the delivery arm unit 20 At a position where the portions 221 and 231 do not interfere with each other, the holding clamper 30 moves up and down to hold the wafer 3 on the delivery arm portion 20. It can be.
[0060]
At this time, since the rotational drive unit 13 includes the eccentric cam 132 and the swing lever 25 having the cam roller 26, the swing lever 25 can be swung by a predetermined angle by the eccentric cam 132. The delivery arm unit 20 can be swung by a predetermined angle to avoid interference between the holding clamper 30 and the delivery arm unit 20, and overlap can be avoided with an easy configuration.
[0061]
Further, when the wafer 3 from which the position of the notch or orientation flat is detected is transferred to the upper claw portions 222 and 232 (buffer stage) while being held by the holding clamper 30, the transfer arm portion 20 is provided with the cam member 27. Since the two lower arm portions 22 and 23 are opened and closed by the pair of cam rollers 28 and 28, the wafer 3 can be moved up and down without interfering with the upper claw portions 222 and 232 of the delivery arm portion 20. Become.
[0062]
Further, since the holding clamper 30 has at least three upper arm portions 33, 34, and 35, and one upper arm portion 33 can move in the horizontal direction, the holding clamper 30 is opened larger than the outer diameter of the wafer 3 and the wafer 3 The edge of the wafer 3 can be securely gripped by moving to a grippable position to enable delivery and further closing.
[0063]
Further, since the opening / closing drive unit 16 has a cam surface 111 formed in the vertical direction and a cam roller 332 movable along the cam surface 111, the holding clamper 30 is formed so as to be opened / closed at the same time. Thus, the holding clamper 30 can move to the height position of the wafer 3 and grip the edge of the wafer 3.
Moreover, since the cam surface 111 is formed in the vertical direction, it is possible to provide a aligner device 1 that can be formed in a small space in the lateral direction and is compact.
[0064]
Note that the configuration of the aligner device 1 is not limited to the above. For example, the configuration of the shift angle rotation driving unit 13 is not limited to the eccentric cam and the cam roller as described above, but other cam mechanisms. For example, a cam mechanism using a groove cam and a cam roller or an irregular cam shape, or a cylinder mechanism using a cylinder instead of the cam mechanism may be used.
[0065]
Further, the opening / closing drive unit 16 may be another cam mechanism instead of the cam mechanism as described above, or may be a cylinder mechanism.
[0066]
Furthermore, the raising / lowering drive of the raising / lowering drive part 15 may be not a ball screw mechanism but a cylinder mechanism, and may use a cam mechanism or a crank mechanism.
[0067]
Moreover, the lower arm parts 22 and 23 which comprise the delivery arm part 20 may be three or more as long as they are formed in a radial equiangular form instead of two. In this case, it may be designed so that the hand can enter and exit.
[Brief description of the drawings]
FIG. 1 is a front view showing a wafer aligner according to an embodiment of the present invention.
FIG. 2 is a plan view of the same.
FIG. 3 is a front cross-sectional view showing an aligner device excluding a detection unit in FIG. 1;
4 is a cross-sectional view taken along line IV-IV in FIG.
5 is a cross-sectional view taken along the line V-V in FIG. 3;
FIG. 6 is a view showing a state in which a holding clamper is raised to a wafer gripping position and opened.
FIG. 7 is a view showing a state in which a holding clamper is further raised to grip a wafer.
FIG. 8 is a view showing a state in which the holding clamper is further raised and the wafer is moved above the buffer stage and opened.
9 is a view showing a state in which the holding clamper is lowered from the state of FIG. 8 to place the wafer on the buffer stage.
10 is a view showing a state in which the holding clamper has moved downward from the state shown in FIG. 9;
FIG. 11 is a plan view showing a state in which the holding clamper and the delivery arm portion overlap each other.
FIG. 12 is a plan view showing a state in which the overlap between the holding clamper and the delivery arm portion is released.
FIG. 13 is a perspective view showing a conventional wafer aligner.
[Explanation of symbols]
1 ... Wafer aligner
3 ... Wafer
5 ... hand
10 ... Machine stand
11 ... Rotation center shaft
111 ... Cam surface (second cam means)
12 ... Opening / closing drive section (first opening / closing drive means)
13: Shift angle rotation drive section (first rotation drive means)
132: Eccentric cam
14: Rotation drive unit (second rotation drive means)
15 ... Elevating drive unit (elevating drive means)
16: Opening / closing drive unit (second opening / closing drive means)
20 ... Delivery arm (delivery means)
21 ... Rotating shaft
22, 23 ... Lower arm (wafer holding arm)
221, 231 ... Lower nail
222, 232 ... Upper nail (buffer stage)
25. Swing arm
26 ... Cam roller
27. Cam member (first cam means)
28. Cam roller (first roller means)
30 ... Holding clamper (holding means)
31 ... Cylindrical shaft part
33, 34, 35 ... Upper arm (clamp arm)
331, 341, 351 ... Claw part (wafer gripping part)
332 ... Cam roller (second roller means)
40... Detection unit (detection means)
44 ... Position detection sensor
47. Wafer presence sensor

Claims (6)

A holding means that is rotatably arranged to hold the wafer, a delivery means that holds the wafer transferred from the robot and delivers it to the holding means, and a detection means that detects a notch or orientation flat position during rotation of the wafer A wafer aligner configured to match a notch or orientation flat position of the wafer with a reference rotational position,
The delivery unit includes the wafer holding unit in two stages, is configured to be rotatable by a predetermined angle by the first rotation driving unit, and can move the holding unit up and down between the upper side and the lower side of the wafer holding unit. The first opening / closing driving means is configured to be openable and closable,
The holding means has a wafer gripping portion that can be raised and lowered with a wafer holding portion of the delivery means interposed therebetween, and is configured to be rotatable by second rotation driving means, and the delivery means by the raising and lowering driving means. It is configured to be movable from a lower position to an upper position with the wafer holding position in between, and to be opened and closed by a second opening / closing drive means for gripping or releasing the edge of the wafer. A wafer aligner. 2. The wafer aligner according to claim 1, wherein the first rotation driving unit is configured to be rotatable by a shift angle for avoiding an overlap between the holding unit and the delivery unit. 3. The wafer aligner according to claim 2, wherein the first rotation driving means includes an eccentric cam and a swing lever having a cam roller engageable with the eccentric cam. The delivery means includes at least two wafer holding arms, and the wafer holding arms include first cam means and first roller means that can be engaged with the first cam means. 2. The wafer aligner according to claim 1, wherein the wafer aligner is configured to be movable in a direction approaching and separating from the axis. The holding means has a plurality of clamp arms arranged in a radial direction from the center of rotation, each clamp arm has a grip part for gripping an edge of the wafer, and at least one clamp arm has the clamp arm 2. The wafer aligner according to claim 1, wherein the wafer aligner is configured to be movable in the horizontal direction by the second opening / closing drive means. The second opening / closing drive means has second cam means having a cam portion formed in a vertical direction, and second roller means arranged to be engageable with the second cam means and movable along the cam portion. 6. The wafer aligner according to claim 5, wherein the wafer aligner is configured to include:

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