JP2008091770A - Wafer aligning device, wafer aligning system, and wafer aligning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quicken with a simple configuration whole aligning processes including a conveyance by a conveying device, in a wafer aligning device which makes a preparation for delivering a wafer to the following process by aligning a notch and an orientation flat and a wafer aligning system including this wafer aligning device and the conveying device. <P>SOLUTION: A wafer aligning device 1 is equipped with: a holder 3 holding a wafer 100 with an adjoining isolation; clampers 41 to 43; clamper supports 411, 421, 431; a chuck 44 which opens and closes these clamper supports to the radial direction; a spindle 45; a spindle rolling mechanism 5; and a sensor portion 6. When a hand of the conveying device holds the wafer 100 from upside in a suspended form and delivers a Bernoulli disk 30 to the wafer aligning device 1, this Bernoulli disk 30 holds the wafer 100 with an adjoining isolation and rotates the spindle 45 in the state of touching the wafer 100 by means of the clampers 41 to 43, and consequently the notch and the orientation flat are detected by the sensor portion 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus for aligning notches and orientation flats that are detected bodies formed on a wafer.

  A wafer is a slice of a single crystal of silicon. When the plane orientation of the wafer changes, the distance between silicon atoms changes, and the microscopic properties change accordingly. For this reason, the wafer is provided with notches and orientation flats for aligning the crystal orientation. In the semiconductor manufacturing process, the wafer is rotated, the notch or orientation flat is detected by a sensor, alignment is performed, and the wafer is transferred to the next process. Devices for aligning such notches and orientation flats have been put into practical use and various proposals have been made (for example, see Patent Documents 1 to 3).

  In Patent Document 1, air is discharged toward a wafer, and the wafer is held close to each other by using a negative pressure generating action by the Bernoulli effect and a positive pressure generating action by the cushion effect (hereinafter simply referred to as “Bernoulli effect”). There is disclosed an alignment apparatus that includes a non-contact holder and a roller rotating tool that rotates against the outer periphery of the wafer to rotate the wafer, and aligns notches and orientation flats.

  Patent Document 2 discloses an aligner device in which a plurality of clampers for holding wafer edges are provided in two upper and lower stages so as to temporarily store two wafers and serve as a buffer. Further, Patent Document 2 has a description that includes a rotation drive unit that rotates the clamper in a closed state, a lift drive unit that moves the wafer up and down between the clampers, and the like, and aligns notches and orientation flats. .

  In Patent Document 3, in a non-contact transfer apparatus that holds wafers in close proximity using the Bernoulli effect by air discharge, a discharge port provided with a fluid passage that generates a swirling flow is used to enhance suction force. A head is disclosed. Patent Document 3 describes that by using this head, the wafer can be rotationally driven in a state in which the wafer is closely separated from the head, and can be applied to a rotational drive device for aligning notches.

Patent Document 4 discloses a configuration in which three heads are provided on a robot hand to float and hold a wafer in a state of being closely separated by the Bernoulli effect. Patent Document 4 describes that the wafer is rotated by adjusting the air discharge from each head to tilt the wafer and rotating the tilt direction.
JP 2002-368065 A Japanese Patent Laid-Open No. 2003-10085 JP 2002-64130 A JP 2004-140058 JP

  However, in the configuration of Patent Document 1, since a roller rotating tool is provided under each roller, there is a problem that the cost is increased and the size is increased. In addition, the peripheral curvature of the roller and the flat wafer must be in point contact, and the position of the aligned notch or orientation flat may be shifted due to the influence of lost motion generated in the roller drive system.

  In the configuration of Patent Document 2, it can be applied to the processing of a wafer that is difficult to bend so that it can be held only by the outer edge as a premise of placing the wafer in two stages. There is a problem that it cannot be applied to the processing of a wafer that is bent due to its own weight. Further, in this configuration, when the clamper and the notch overlap and cannot be detected because the notch is hidden by the clamper, the wafer is temporarily lifted by the lifting drive unit in order to rotate the wafer to change the relative position between the clamper and the notch. There was a need.

  In order to apply the method of rotating a wafer only by controlling air discharge described in Patent Documents 3 and 4 to a wafer alignment apparatus, the accuracy of aligning notches may not be sufficient. Further, it is difficult to align the wafer at a predetermined center position. Furthermore, there is a problem that the position of the aligned notch is easily displaced.

  Accordingly, the present invention relates to a wafer alignment apparatus that aligns notches and orientation flats and prepares to deliver a wafer to the next process, and a wafer alignment system including the apparatus and the transfer apparatus. It aims at speeding up the whole alignment process including the conveyance by a simple structure. In addition, to achieve this purpose, when the clamper overlaps with the notch or orientation flat and the notch or orientation flat is hidden behind the clamper and cannot be detected, this state can be eliminated with a simple configuration without lifting the wafer by the lifting drive etc. The purpose is to do.

  (1) The alignment apparatus of the present invention includes a holder, an air discharge unit, a plurality of clampers, a clamper moving unit, a clamper rotating unit, a sensor, and a control unit.

  The holder has a discharge port formed on a holding surface facing one surface of the wafer. The air discharge unit discharges air from the discharge port. The plurality of clampers include at least one moving clamper that is movable along a radial direction of the wafer between a contact position that contacts the outer periphery of the wafer and a retracted position that is separated from the outer periphery of the wafer, Are in contact with the outer periphery of the wafer at different rotational positions. The clamper moving unit positions the moving clamper at either the contact position or the retracted position. The clamper rotating unit integrally rotates the plurality of clampers around the central axis of the wafer. The sensor detects an object to be detected formed on a part of the outer periphery of the wafer. The control unit controls the amount of air discharged from the air discharge port by the air discharge unit and the position of the moving clamper by the clamper moving unit to hold the wafer in a state of being separated from the holding surface. The rotation of the plurality of clampers by the clamper rotation unit is controlled based on the detection result of the sensor.

  In this configuration, a wafer that is bent due to its own weight, such as a wafer having a strain at the center or a thin wafer, is held in a state of being closely separated from the holder. Further, in this configuration, since the clamper can be rotated while being in contact with the periphery of the wafer, the wafer can be rotated at high speed and reliably, and the position of the detected object can be determined after detecting the detected object. Hard to slip.

  (2) A swirling flow forming body that generates a swirling flow of air may be provided at the discharge port.

In this configuration, since the swirling air is discharged from the discharge port, the wafer can be rotated in a state of being separated from the holder only by discharging a fixed amount without controlling the discharge amount of the air. it can.

  (3) A wafer alignment method according to the present invention is a wafer alignment method for detecting a rotational position of the detected object using the wafer alignment apparatus according to (1) or (2), wherein the holding step And a detection step.

  In the holding step, the moving clamper is positioned in the retracted position when the wafer is loaded to the position facing the holding surface, the air is discharged from the discharge port, and the moving clamper is separated from the holding surface in the proximity of the holding surface. The plurality of clampers are brought into contact with the outer periphery of the wafer by moving to the contact position. In the detection step, the detected object is detected by the sensor while rotating the plurality of clampers.

  The clamper rotating unit rotates the wafer while the movable clamper is in the contact position in the holding process, so that the wafer can be rotated at high speed and reliably, and the position of the detected object is shifted after the detected object is detected. Hateful.

(4) When the sensor does not detect the detected object in the detection step, it is preferable to perform the re-holding step before performing the detection step.
In the re-holding step, when the sensor does not detect the detected object in the detection step, the moving clamper is positioned at the retracted position, and the discharge of air from the discharge port is adjusted, After the wafer is rotated around the central axis by a predetermined amount, the movable clamper is moved to the contact position to bring the plurality of clampers into contact with the outer periphery of the wafer.

In the method of this configuration, when the clamper and the position of the detected object overlap, the discharge of air is adjusted with the moving clamper positioned at the retracted position. Accordingly, the position of the detected object can be shifted from the position of the clamper by rotating the wafer by a predetermined amount while keeping the wafer in close proximity. Therefore, it is not necessary to lift the wafer or change the wafer, so that the time for detecting the detection target can be shortened.
The “predetermined amount of rotation” of the present invention may be an amount that can eliminate the state where the clamper and the position of the object to be detected overlap with each other, and does not have to be a strictly constant amount. The predetermined rotation amount may be determined based on the rotation time. For example, it can be set to about 1 to 3 seconds.
In the re-holding step, when the configuration of the swirling flow forming body (2) is used, the wafer can be rotated only by keeping the discharge amount constant. In this case, adjusting whether the discharge amount is kept constant or turned off corresponds to “adjusting the discharge of air from the discharge port”. The same applies to the seventh aspect.
Furthermore, in the re-holding step, the air discharge amount may be adjusted and rotated without the configuration of the swirl flow forming body. This method also corresponds to “adjusting the discharge of air”.

(5) An alignment system of the present invention is a wafer alignment system including the wafer alignment apparatus according to any one of (1) and (2), and includes a wafer transfer apparatus.
The wafer transfer apparatus includes a hand, a hand moving unit, and a transfer control unit. The hand holds the wafer in contact with or in close proximity from the direction facing the holding surface of the holder. The hand moving means moves the hand. The transfer control unit controls the wafer holding means and the hand moving means so as to carry the wafer to a position facing the holding surface in the wafer alignment apparatus.

  In this configuration, the transfer device includes a hand that holds the wafer facing the holding surface of the holder. Accordingly, the wafer is delivered at a position where the holder and the hand face each other across the front and back surfaces of the wafer. At the time of wafer delivery, the hand of the transfer device is moved from between the holder and the wafer. There is no need to insert or lift the wafer by the lift drive unit, and the apparatus can be simply configured. Further, since such an operation is not necessary, the entire alignment process including the conveyance by the conveyance device can be speeded up.

  (6) A wafer alignment method of the present invention is a wafer alignment method for detecting the position of an object to be detected using the wafer alignment system according to (5), a carry-in step, a holding step, A detection step and an unloading step.

  In the carrying-in process, the wafer is held on the holding surface of the holder by moving the hand with the movable clamper positioned in the retracted position in advance. In the holding step, air is discharged from the discharge port, the moved wafer is moved to the contact position in a state where the carried wafer is separated from the holding surface, and a plurality of clampers are brought into contact with the outer periphery of the wafer. The wafer is not held. In the detection step, the detection target is detected by the sensor while rotating the plurality of clampers. In the unloading process, when the detected object is detected, the hand holds the wafer held by the holder, positions the moving clamper at the retracted position, stops the discharge of air from the discharge port, and moves the hand. Unload the wafer.

  In this configuration, the wafer carry-in process and the wafer carry-out process are performed using a hand that is held in contact with or in close proximity to the wafer from the direction facing the holding surface of the holder. Therefore, the holder and the hand hold the opposite sides of the wafer. In this configuration, since it is not necessary to insert a hand between the wafer and the holder that are closely separated from each other or to change the hand to avoid this, the wafer carry-in process and the wafer carry-out process can be performed smoothly. Therefore, with this configuration, the entire alignment process including conveyance by the conveyance device can be speeded up.

  (7) When the sensor does not detect the detected object in the detection step, it is desirable to perform a re-holding step. In the re-holding step, after adjusting the discharge of air from the discharge port and rotating the wafer by a predetermined amount around a central axis, the movable clamper is moved to the contact position to move the plurality of clampers The wafer is brought into contact with the outer periphery of the wafer.

  In this configuration, even if the detection target is hidden behind the clamper and cannot be detected, according to the re-holding process, it is necessary to insert the clamper of the transfer device from between the holder and the wafer or lift the wafer by the lift drive unit. Absent. Therefore, the time for detecting the detection target can be shortened.

  (8) In the wafer alignment method described in (7) above, after the carrying-in process, the holding process and the re-holding process are performed while the hand is stopped at a position facing the holding surface in the wafer alignment apparatus. desirable.

  On the premise of the method (7), after the carrying-in process, the hand can be stopped at a position facing the holding surface in the wafer alignment apparatus. In this configuration, the detection process and the re-holding process are performed while the hand is stopped at a position facing the holding surface of the wafer alignment apparatus. Therefore, there is little waste of the process of the wafer alignment method. Therefore, in this method, the entire alignment process including the conveyance by the conveyance device can be speeded up.

  When the detection process is performed with the hand held at a position facing the holding surface, when the hand is brought into contact with the wafer, that is, when the hand sucks the wafer, even if the clamper is rotated, The clamper of the wafer alignment apparatus does not cause interference. If the hand is provided with a head that utilizes the Bernoulli effect, a clamper is required to maintain the wafer angle during unloading, so it is necessary to prevent interference between the hand clamper and the wafer alignment device clamper. As a method for preventing the interference, there is a method in which the hand is moved away from the holding surface or the hand clamper is opened larger than the clamper of the wafer alignment apparatus.

  According to the present invention, a wafer alignment device that detects the position of an object to be detected such as a notch or an orientation flat and prepares to deliver the wafer to the next process, and a wafer alignment device including this device and a transfer device In the system, the entire alignment process including the transfer by the transfer device can be speeded up with a simple configuration.

Hereinafter, a wafer alignment apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a side view of the wafer alignment apparatus 1. FIG. 2 is a plan view of the wafer alignment apparatus 1 and shows a view from the upper surface side of the Bernoulli disk 30 corresponding to the holding surface of the present invention. However, FIG. 1 shows a view of the clamper 41 and the clamper support portion 411 cut along the section AA of FIG. Further, the clampers 42 and 43 and the clamper support portions 421 and 431 in FIG. 1 are illustrated in cross-sectional views cut along the B1-B1 cross section and the B2-B2 cross section. In addition, inside the break lines 101 and 102, a sectional view cut along a plane passing through the rotation center 37 is shown.

  As shown in FIG. 1, the wafer alignment apparatus 1 includes a pedestal portion 2, a holder 3, clampers 41 to 43, clamper support portions 411, 421, and 431, a chuck 44, a spindle 45, and spindle rotation. A mechanism 5, a sensor unit 6, and a control panel 90 are provided.

The holder 3 includes a Bernoulli disk 30 and a support base 301. The Bernoulli disk 30 includes a plurality of air discharge ports 31 to 36 (see FIG. 2), discharges air toward the wafer, and generates negative pressure by the Bernoulli effect and positive pressure generation by the cushion effect (hereinafter simply “ The wafer 100 is floated by the “Bernoulli effect” and is held in close proximity to the holder 3. The support base 301 fixes the Bernoulli disk 30 to the center of the chuck 44 (position of the rotation center 37).
Note that the surface of the Bernoulli disk 30 that the wafer 100 faces corresponds to the holding surface of the present invention.

  The clampers 41 to 43 are arranged at different rotational positions on the outer periphery of the wafer 100. Each of the clampers 41 to 43 includes a receiving portion that comes into contact with the outer periphery of the wafer 100.

  The clamper support portions 411, 421, and 431 fix the clampers 41 to 43, and transmit the power of the chuck 44 to the clampers 41 to 43. The chuck 44 is an electromagnetic chuck that applies a force in the direction of the rotation center 37 and has a movable portion that opens and closes in the radial direction. By opening and closing the movable portion of the chuck 44, the clampers 41 to 43 can be brought into contact with the wafer 100 and retracted from the wafer 100 via the clamper support portions 411, 421, and 431.

The spindle 45 fixes the chuck 44 and the pulley 52.
The spindle rotation mechanism 5 includes a motor 50, a pulley 51, a pulley 52, and a belt 53. The motor 50 is a drive source that rotates the spindle 45. The controller 9 is connected to a control panel 90 having a built-in drive unit for the motor 50.

  The pulley 51 is fixed to the rotation shaft of the motor 50 and rotates around the rotation center 54. The pulley 52 is fixed to the spindle 45. Grooves for receiving the belt 53 are formed on the outer circumferences of the pulleys 51 and 52. The belt 53 is made of, for example, a rubber belt, and transmits power from the pulley 51 to the pulley 52.

  The sensor unit 6 includes a light emitting element 60, a sensor 61, and a support unit 63 that supports them, and detects a notch (corresponding to the notch of the present invention). The light emitting element 60 is composed of, for example, a light emitting diode, and generates laser light. A hood (not shown) is attached to the front side surface of the light emitting element, and blocks radiation of light in directions other than the front of the light emitting element. The light emitting element 60 emits light toward the notch when the wafer 100 rotates. The sensor 61 is composed of a photodiode or the like, and is arranged at a position where the light from the light emitting element 60 can be received. Since the wafer 100 passes light when the wafer 100 rotates and reaches the position of the notch, the notch can be detected.

  The pedestal 2 includes a pedestal 20, a support 21, a spindle support shaft 22, and a motor support 23. The pedestal 20 is a pedestal that supports the entire apparatus. 1, the hollow support shaft 22 is fixed from the base 20 via the support base 21 in order to pivotally support the spindle 45 at the rotation center 37. The spindle 45 and the bearing are inserted in the inside. Further, the motor support 23 fixes the motor 50.

  In addition, in order to supply air to the holder 3 to rotate, it is necessary to route piping from an external air pump or an air discharge port in a factory. As the routing method, for example, a universal joint (rotary joint) can be used between the inside of the spindle 45 and the support shaft 22 of the base portion 2. In this method, the pipe of the holder 3 is inserted into the spindle 45 from the outer peripheral surface 451 of the spindle 45, and a universal joint (for example, a rubber ring 452 and a groove on the inner periphery of the support shaft 22 as shown in FIG. 1). The air piping is drawn out to the air inlet 221 of the support shaft 22 through the air pocket 222. Thereby, even if the holder 3 rotates, air can be supplied from the air inlet 221 to the holder 3. As another routing method, a cable holder formed by connecting chains may be used. In order to detect the notch, it is not necessary to rotate the holder 3 beyond 360 degrees. Therefore, the air pipe can be routed to the holder 3 without using a universal joint.

  The control panel 90 includes a control unit 9, an operation unit 901 that receives operation inputs of various operations, a liquid crystal display unit 902 that displays an operation status, and a current drive unit 903 that drives a current flowing through the motor 50 and the like. Yes. The control unit 9 includes a CPU, a RAM that temporarily stores the results calculated by the CPU, and a ROM that stores control information. The control unit 9 discharges air from the holder 3, opens and closes the movable unit of the chuck 44, and current of the motor 50. Control the drive. The ROM of the control unit 9 stores a control program for executing a detection routine 91, a re-holding routine 92, and a workpiece transfer routine 93.

  The detection routine 91 includes a step of detecting the notch by holding the wafer 100 in the state of being closely separated by the Bernoulli disk 30 and by contacting the clampers 41 to 43 with the wafer 100 and rotating the spindle 45.

The re-holding routine 92 is executed when the notch overlaps with the clampers 41 to 43 and is hidden, and the sensor unit 6 cannot detect light from the groove of the notch. The re-holding routine 92 rotates the wafer 100 by the swirling flow discharged from the Bernoulli disk 30 for a predetermined time in a state where the clampers 41 to 43 are once retracted from the wafer 100, and the notches and the clampers 41 to 43 overlap. Eliminate. Thereafter, the re-holding routine 92 brings the clamper 100 into contact with the wafer. The control unit 9 instructs the execution of the detection routine 91 again after the re-holding routine 92.
The workpiece delivery routine 93 includes a carry-in process and a carry-out process for delivering the wafer 100 to and from the transfer device.

  As shown in FIG. 2, the Bernoulli disk 30 of the holder 3 is provided with a plurality of heads 31 to 36 having air discharge ports at positions near the outer periphery of the Bernoulli disk 30.

  Further, the clampers 41 to 43 are arranged at positions where the outer periphery of the wafer 100 is substantially equally divided. The clampers 75 to 77 are hand clampers of a transfer device (corresponding to a transfer device 7 in FIG. 6 described later) that carries the wafer 100 into the wafer alignment device 1. FIG. 2 shows the positions at which the clampers 75 to 77 arrive at the time of carry-in. As shown in FIG. 2, the clamper of the transfer device is also arranged at a position where the outer periphery of the wafer 100 is substantially equally divided, like the clampers 41 to 43. In order to prevent interference between the clampers 41 to 43 and the clampers 75 to 77, these clampers are arranged out of phase with each other.

  FIG. 3 shows an embodiment of the receiving portion of the clamper 41 in the AA cross section of FIG. In the embodiment of the clamper 41 </ b> A in FIG. 3A, the clamper 41 </ b> A is provided with a 4102 that supports the lower surface of the wafer 100 and a surface 4101 that contacts the outer periphery of the wafer 100. In this way, the contact with the wafer 100 can be stabilized by pressing with two surfaces. Further, as in the embodiment of the clamper 41B in FIG. 3B, a configuration in which a presser 4103 that presses the upper portion of the wafer 100 is further provided is also possible. Further, as shown in FIG. 3C, the taper surfaces 4104 and 4105 inclined with respect to the surface of the wafer 100 may be used.

  Although the clamper 41 has been described as an example in FIG. 3 described above, the other clampers 42 and 43 have the same shape.

  4A and 4B are perspective views showing the configuration of the head 31. FIG. 4A is a perspective view from obliquely below, and FIG. 4B is a perspective view from obliquely upward. 4C and 4D are cross-sectional views of the head 31, FIG. 4C is a cross-sectional view taken along the line CC in FIG. 4A, and FIG. 4D is a line DD in FIG. It is sectional drawing. The head 31 in FIG. 4 represents a configuration example of the heads 31 to 36 as a representative. As described below, the head 31 is not configured to simply hold the wafer 100 in close proximity but to generate a swirling flow from the head 31, and the clampers 41 to 43 are retracted from the wafer 100 in the re-holding routine 92. It is suitable for rotating the wafer 100 in the state.

  The head 31 includes a concave portion 83 having an inner peripheral surface that is circumferential, a flat end surface 82B that is formed on the opening side of the concave portion 83 and that faces the wafer 100, and a discharge port that faces a supply fluid to the inner peripheral surface of the concave portion 83. And a fluid passage 85 for discharging the material from 84 into the recess 83 along the inner circumferential direction of the recess 83.

  The fluid passage 85 is drilled perpendicularly to the closed end surface 82 </ b> A from the fluid inlet 86 provided on the closed end surface 82 </ b> A of the swirl flow forming body 82, and further horizontally drilled on the inner peripheral surface of the recess 83. It reaches the discharge port 84 that faces it. That is, the fluid passage 85 communicates the fluid introduction port 86 and the discharge port 84 and discharges the supply fluid from the discharge port 84 into the recess 83 along the circumferential direction thereof. A swirling flow is generated inside the recess 83 by the supplied fluid.

  Two sets of the fluid introduction port 86, the fluid passage 85, and the discharge port 84 are provided, and the fluid (here, air) discharged from the two sets of the discharge ports 84 is discharged in the same direction along the circumferential direction. Strengthen the swirl flow mutually.

  Further, the opening edge of the recess 83 is chamfered to form an inclined surface 83A and has a trumpet diameter, and the swirling flow generated in the recess 83 can quickly flow out of the recess 83 by the inclined surface 83A.

  In the head 31 configured as described above, air is supplied to the fluid introduction port 86 from an air supply device such as an air pump. The air is blown into the recess 83 from the discharge port 84 via the fluid passage 85. The blown air is rectified as a swirling flow in the internal space of the recess 83 and then flows out of the recess 83. At this time, when the wafer 100 is disposed at an appropriate position facing the flat end surface 82A of the swirl flow forming body 82, the atmospheric pressure supply from the outside to the recess 83 is restricted. In this state, the air blown into the recess 83 from the discharge port 84 gradually decreases the density of air molecules per unit area due to the entrainment effect (attracting phenomenon of viscous fluid) and centrifugal force, and the swirling flow in the recess 83 The pressure in the center decreases and negative pressure is generated. As a result, the wafer 100 is pressed by the ambient atmospheric pressure and sucked toward the flat end face 82A. On the other hand, when the distance between the flat end surface 82A and the wafer 100 approaches, the air discharged from the recess 83 is restricted. Thereby, since the flow velocity of the air blown from the discharge port 84 becomes slow, the pressure at the center of the swirl flow in the recess 83 increases. As a result, the wafer 100 is pushed back to the pressure in the recess 83 and is separated from the flat end surface 82A, and is maintained at a point where the mass and the suction force of the wafer 100 are balanced. Further, the wafer 100 is stably held in close proximity by the air film interposed between the flat end face 82A and the wafer 100.

  Thus, since air is jetted along the circumferential direction in the recess 83 to generate a swirling flow, the suction force due to the negative pressure between the flat end surface 82B and the wafer 100 becomes strong. Moreover, the wafer 100 can be rotated with the whole heads 31-36 by matching the turning direction of the turning flow path 85 of the heads 31-36. Thereby, the wafer 100 can be rotated in the state where the clampers 41 to 43 are retracted from the wafer 100 by the re-holding routine 92 described in FIG.

In the description of FIG. 4 described above, two sets of the fluid introduction port 86, the fluid passage 85, and the discharge port 84 are provided. However, only one set may be provided, or three or more sets may be provided.
Further, although the fluid introduction ports 86 are individually provided, the fluid introduction ports 86 may be shared, and the fluid passages 85 and the discharge ports 84 may be provided by branching from the fluid introduction ports 86.
Further, the fluid passage 85 is formed by a combination of a vertical path and a horizontal path. However, the fluid path 85 is not limited to such a path, and the fluid path 85 extends from the fluid inlet 86 to the circumferential direction of the recess 83. What is necessary is just to form so that air may be blown along.
Further, in order to adjust the rotation speed of the wafer 100 by the swirl flow, the swirl direction of the swirl flow path 85 of the heads 31 to 36 may be reversed in any of the heads 31 to 36. Since the rotational moment generated in the wafer 100 by the swirl flow of each head 31 is canceled, the rotational speed of the wafer 100 can be adjusted. Further, the rotational speed of the wafer 100 can be adjusted only by changing the flow rate supplied to the Bernoulli disk 30 including the heads 31 to 36.

  In addition to the configuration shown in FIG. 4, in the configuration in which the swirl flow is discharged by the heads 31 to 36 alone, the wafer 100 is discharged by discharging the swirl flow while the clampers 41 to 43 are retracted from the wafer 100. Can be rotated and a rehold routine 92 can be executed. According to the heads that generate these swirl flows, the wafer 100 can be rotated only by discharging a certain amount of air without finely controlling the amount of air in the re-holding routine 92. For example, it is not necessary to control the discharge of air in order to rotate the wafer 100.

  Furthermore, the configuration shown in FIG. 4 is not essential for the purpose of merely holding the wafer 100 in close proximity and floating by the Bernoulli effect in order to simply execute the detection routine 91.

  FIG. 5 is a side view showing the state in which the transfer device 7 is close to the wafer on the Bernoulli disk 30 of the wafer alignment device as seen from the same direction as FIG. However, the left side of the arm 700 below the Bernoulli disk 30 is omitted. Further, the clampers 41 to 43 are represented by cross sections AA, B1-B1, and B2-B2 in FIG.

The transport device 7 includes an arm 700, a hand 70, and a transport control unit 79.
The arm 700 is for moving the hand 70 and is constituted by, for example, a multi-indirect robot. The arm 700 in FIG. 5 shows the tip of an arm such as a multi-indirect robot.
The hand 70 includes a hand rear end 71, a hand front end 72, heads 731 to 736 stored in the hand front end 72, clampers 75 to 77 that contact the wafer 100, and a chuck 78 that opens and closes the clampers 75 to 77.

  The hand rear end 71 is fixed to the arm 700 and incorporates a chuck 78. Further, the electrical wiring of the chuck 78 and the air piping of the heads 731 to 736 are passed through the arm 700.

  The hand tip 72 has a structure in which the Bernoulli disk 30 is substantially inverted, and stores the heads 731 to 736.

  The heads 731 to 736 are attached to the transport head attachment surface 730 that faces the Bernoulli disk 30. The heads 731 to 736 suspend and hold the wafer 100 close to and away from the holder 3 by the Bernoulli effect. According to the Bernoulli effect, even when the heads 731 to 736 are above the wafer 100, the wafer 100 can be held under the heads 731 to 736 in a non-contact manner.

  Note that the head of the transport device 7 does not necessarily need to be configured to discharge a swirling flow as shown in FIG. It suffices if the hand tip 72 of the transport device 7 can be closely separated by the Bernoulli effect by air discharge. Alternatively, a device that does not use the Bernoulli effect may be used. For example, the wafer 100 may be vacuum-sucked and the hand 70 may be brought into contact with the wafer 100 to be conveyed.

Similarly to the clampers 41 to 43, the clampers 75 to 77 have moving clampers that contact the wafer 100 or retreat from the wafer 100. Further, the shapes of the portions where the clampers 75 to 77 are in contact with the wafer 100 are configured such that the clampers shown in FIG. Further, the clampers 75 to 77 are fixed to the movable part of the chuck 78.
The chuck 78 is an electromagnetic chuck provided at the rear end 71 of the hand, and opens and closes the clampers 75 to 77.

  The conveyance control unit 79 is stored in a control panel having the same configuration as the control panel 90. The transfer control unit 79 controls the movement operation of the arm 700, the discharge amount of air sent to the heads 731 to 736, the opening and closing of the chuck 78, and the like. Communicate information. The conveyance control unit 79 receives control information from the control unit 9. For example, it receives whether or not the control unit 9 has output an instruction signal, the state of the sensor unit 6, and the like regarding the rotation operation of the spindle 45, the discharge of air sent to the heads 31 to 36, and the opening and closing of the chuck 78. Further, the conveyance control unit 79 transmits to the control unit 9 whether or not the conveyance control unit 79 has output an instruction signal.

The flowchart of FIG. 6 is a carrying-in process of carrying in from the transfer device to the wafer alignment device in the workpiece transfer process. This step corresponds to the step executed in the workpiece transfer routine 93 described with reference to FIG.
In ST <b> 1, the transfer control unit 79 brings the arm 700 holding the wafer 100 close to the wafer alignment apparatus 1 and inserts the hand tip 72 so that the wafer 100 is under the sensor unit 6.
In ST <b> 2, the control unit 9 receives a signal indicating that the movement of the hand tip 72 is completed from the conveyance control unit 79 and starts discharging air from the heads 31 to 36 of the Bernoulli disk 30.

In ST3, the control unit 9 instructs to close the movable part of the chuck 44 after ST2 or at substantially the same timing, and the clampers 41 to 43 come into contact with the wafer 100 (clamped state).
In ST4, the transfer control unit 79 receives the signal of completion of ST3 from the control unit 9 and instructs to open the movable part of the chuck 78 of the transfer apparatus 7, so that the clampers 75 to 77 are retracted from the wafer 100. (Unclamped state).
In ST5, in parallel with ST4, the discharge of air from the heads 731 to 736 of the transport apparatus 7 is stopped. Thereafter, in ST6, the arm 700 of the transfer device 7 is retracted.

  As described above, since the transfer apparatus 7 can transfer the wafer 100 in a state where the heads 731 to 736 face downward, the wafer 100 does not need to be inverted or raised. Therefore, the configuration for delivering the wafer 100 can be simplified.

  7 is a process in which the wafer alignment apparatus 1 detects a notch. This step is a step performed following the operation shown in FIG. 7 correspond to the detection routine 91 of the control unit 9, and ST14 to ST19 correspond to the re-holding routine 92 of the control unit 9.

In ST11, the control unit 9 turns on the operation of the sensor unit 6. In other words, laser light is emitted from the light emitting element 60 and light reception by the sensor 61 is started.
In ST12, the motor 50 is rotated, and the spindle 45, the clampers 41 to 43, and the Bernoulli disk 30 are started to rotate.
In ST13, the control unit 9 determines whether the sensor unit 6 has detected a notch. In ST14, the control unit 9 determines whether or not the spindle 45 has rotated once. As long as the control unit 9 determines that the signal from the sensor unit 6 is not detecting a notch (NO in ST13) and the rotation has not reached one revolution (NO in ST14), the control unit 9 determines in ST12. The rotation of the motor 50 is continued. When the control unit 9 determines that the signal received from the sensor unit 6 is in a state of detecting a notch (YES in ST13), the rotation of the spindle 45 is stopped in ST15, and the flow in FIG.

  If it is determined in ST15 that the spindle 45 has rotated one revolution (YES in ST14), the process moves to ST16. Since a notch is formed in any one of the outer circumferences of the wafer 100, normally, if the spindle 45 rotates once, the sensor 61 should be able to detect the notch in the detection process of ST11 to ST13. However, when the clampers 41 to 43 come into contact with the wafer 100 at positions where the notches are hidden by the clampers 41 to 43, the sensor 61 cannot detect the light of the light emitting element 60, and detects the notch even if it rotates once. Can not. Therefore, the following ST16 to ST19 are performed.

In ST16, the control unit 9 once opens the movable part of the chuck 44 of the wafer alignment apparatus 1 so that the clampers 41 to 43 are retracted from the wafer 100 (unclamped state).
In ST17, the control unit 9 starts air discharge from the heads 31 to 36 of the wafer alignment apparatus 1. Since the heads 31 to 36 are provided with the swirl flow forming body 82 at the discharge ports, the wafer 100 rotates when the heads 31 to 36 start to discharge air.
In ST18, the control unit 9 determines whether or not a predetermined time has elapsed, and waits until the predetermined time is reached. By ST17 and ST18, the state where the notch overlaps with any one of the clampers 41 to 43 can be eliminated. The predetermined time is a predetermined amount of rotation that can eliminate this state, and a time required for rotation, for example, about 1 to 3 seconds. The predetermined rotation amount may be an amount that can eliminate this state, and does not need to be strictly constant.
In ST19, the controller 9 again closes the movable portion of the chuck 44 of the wafer alignment apparatus 1 so that the clampers 41 to 43 are in contact with the wafer 100 (clamped state). Thereafter, returning to ST12, ST12 to ST14 are repeated. If the sensor 61 cannot detect the notch even after performing the processing from ST12 to ST14 again, the processing from ST15 to ST18 is performed again.

  Next, the flowchart of FIG. 8 is a workpiece transfer process for unloading from the wafer alignment apparatus to the transfer apparatus, and is a process performed when the notch / orientation flat detection process of FIG. 7 is completed. As a premise for executing the flow of FIG. 8, it is assumed that the transport control unit 79 receives a signal indicating the end of the detection process from the control unit 9.

In ST21, the transfer control unit 79 moves the empty arm 700 not holding the wafer 100 close to the wafer alignment apparatus 1 from the upper surface of the wafer 100 with the clampers 75 to 77 retracted, and the hand tip 72 is moved. It is inserted under the sensor unit 6.
In ST <b> 22, the conveyance control unit 79 starts air discharge from the heads 731 to 736 of the hand 7.
In ST23, the transfer control unit 79 instructs to close the movable part of the chuck 78 of the transfer device 7 after ST22 or at the same timing as ST22, and the clampers 75 to 77 contact the wafer 100 (clamped state). .
In ST 24, the control unit 9 receives the completion signal of ST 22 and ST 23 from the transfer control unit 79 and instructs to open the movable part of the chuck 44 of the wafer alignment apparatus 1, and the clampers 41 to 43 are retracted from the wafer 100. (Unclamped)
In ST25, in parallel with ST24, the control unit 9 stops air discharge from the heads 31 to 36 of the wafer alignment apparatus 1.
In ST26, when the transfer control unit 79 receives a signal from the control unit 9 indicating that the air discharge in ST25 has been stopped, the transfer control unit 79 retracts the arm 700 of the transfer apparatus 7 holding the wafer 100.

It supplements about the above embodiment.
The above embodiments are not limited to the detection of notches, but can be applied to the detection and positioning of a detection object engraved on a wafer in order to detect the surface orientation of the wafer, such as an orientation flat.
Further, the number of heads (31 to 36) is not limited to six. If the wafer 100 can be floated and the wafer 100 can be rotated by discharging air, the number of heads (31 to 36) may be 6 or more or 6 or less. You may provide in the center of Bernoulli disk 30. The same applies to the heads 731 to 736 of the transport device 7.

In addition, the chuck 44 moves all the clampers 41 to 43 in the radial direction, but it is also possible to move only some of the clampers and fix the other clampers. The number of clampers is not limited to three. The number of contact points of the clamper is required to be two or more, but if there are three or more contact points of the clamper, the state in contact with the wafer 100 is stabilized. The number of clampers may be four or more. The description of the clampers 41 to 43 described here also applies to the clampers 75 to 77. However, with regard to the clampers 41 to 43 on the wafer alignment apparatus 1 side, if this number is large, the possibility of overlapping with the notch increases, and the number of times the re-holding routine 92 is performed increases.
Further, as another configuration of the clampers 41 to 43 and the like, not only the clampers 41 to 43, the clamper support portions 411, 421, 431, and the chuck 44, as long as they are in contact with the wafer 100 and maintained at a predetermined center position. Anyway. The power of the chuck 44 may be air or hydraulic pressure instead of an electromagnetic method. The same applies to the transport device 7.

  Further, as another shaft support method of the spindle 45 different from that in FIG. 1, a configuration in which the spindle 45 is hollow and a shaft and a bearing fixed to the pedestal portion 2 therein may be provided.

  The light emitting element 60 and the sensor 61 only need to be able to detect a notch through light through the wafer 100, and may be in a positional relationship in which the wafer 100 is sandwiched between the light emitting element 60 and the sensor 61. For example, the light emitting element 60 in FIG. 1 may be disposed on the lower side and the sensor 61 may be disposed on the upper side.

  In the above description, the spindle rotating mechanism 5 and the spindle 45 have been described. However, the holder 3 and the heads 31 to 36 can be rotated, and air can be supplied to the holder 3 even if they rotate. Any configuration is possible. For example, a configuration in which the chuck 44 is directly rotated by a motor without using the belt 53 may be employed. In this case, the air piping method can be performed, for example, by hollowing the motor, passing the air piping, and connecting to the pump using a universal joint.

Further, with respect to ST17 shown in FIG. 7, the wafer alignment apparatus 1 does not need to change the wafer 100 or move it up and down. Accordingly, the notch positioning shown in the flow of FIG. 8 may be performed while the hand tip 72 of the transport device 7 is not retracted and the hand tip 72 is retained above the Bernoulli disc 100. In order to perform the detection process while being stopped in this way, it is necessary that the clampers 75 to 77 prevent interference with the clampers 41 to 43 when the clampers 41 to 43 of the wafer alignment apparatus rotate. As a method for preventing this interference, for example, there are the following methods.
(A1) One is a method of raising the hand 70 about several millimeters in the direction 105 (see FIG. 5) away from the Bernoulli disk 30. Thereby, interference with the clampers 41 to 43 can be avoided. Note that the sensor unit 7 and the hand tip 72 do not interfere with each other when the wafer 100 is not held and the wafer 100 moves in the direction 105. Specifically, the support portions of the clampers 75 to 77 are provided at positions where there is no interference with the sensor portion 7 when moving in the direction 105.

(A2) Further, the clamper strokes 75-77 of the hand can be retracted outside the clampers 41-43 of the wafer alignment apparatus by taking a large stroke of the clamper. Thereby, interference with the clampers 41 to 43 can be prevented.
(B) As another method, a configuration can be adopted in which the hand 70 of the transfer apparatus sucks the wafer. There is a method in which the suction surface of the hand tip 72 protrudes toward the holding surface inside the clampers 41 to 43 so as not to interfere with the clampers 41 to 43 of the wafer alignment apparatus.

Furthermore, the heads 75 to 77 of the transfer device 7 may be configured to generate the swirl flow shown in FIG. 5, and the heads 75 to 77 may rotate the wafer 100 in ST16 of FIG. In this case, the heads 31 to 36 on the wafer alignment apparatus 1 side need not be configured to generate the swirling flow shown in FIG.
In the above, the configuration of the positional relationship has been described in which the wafer alignment device 1 is the lower side of the wafer 100 and the transfer device 7 is the upper side of the wafer 100. However, the holder 3 and the hand tip 72 are connected to each other. As long as the wafer 100 is transferred from the surfaces opposite to each other, and the wafer 100 is transferred, the holder 3 may face in any direction. For example, the positional relationship between the holder 3 and the hand tip 72 shown in FIG. Further, the wafer 100 may be exchanged from the direction in which the wafer tip 100 is erected and the hand tip 72 and the holder sandwich the wafer 100.
Further, the liquid crystal display unit 902 of the control panel 901 is not essential, and the control panel 90 only needs to include at least the control unit 9 and the current driving unit 902. If the predetermined detection routine 91, the re-holding routine 92, and the workpiece transfer routine 93 are executed at the same time as the power is turned on, the operation unit 901 is also unnecessary.

It is a side view of a wafer alignment apparatus. It is a top view of a wafer alignment apparatus. It is a figure showing the Example of the shape of a clamper. It is a figure showing the structural example of the head of a wafer alignment apparatus. It is a figure showing the state which the conveyance apparatus adjoined to the wafer on the Bernoulli disk of a wafer alignment apparatus. It is a flowchart of a workpiece | work delivery process (conveyance apparatus-> wafer alignment apparatus). It is a flowchart of a detection process. It is a flowchart of a workpiece | work delivery process (wafer alignment apparatus-> conveyance apparatus).

Explanation of symbols

1-wafer alignment device, 100-wafer, 2-pedestal,
3-holder, 30-Bernoulli disk, 301-support base,
31-36 head, 37- center of rotation,
41-43-clamper, 411, 421, 431-clamper support,
4101, 4102-surface, 4103-presser, 4104, 4105-tapered surface,
44-chuck, 45-spindle, 5-spindle rotation mechanism,
50-motor, 51, 52-pulley, 53-belt, 54-center of rotation,
6-sensor part, 60-light emitting element, 61-sensor,
7-Transfer device, 70-Hand, 700-Arm,
71-hand rear end, 72-hand front end, 730-transport head mounting surface,
731-736 heads,
75-77-clamper, 78-chuck, 79-conveyance control unit,
82-swirl flow forming body, 82A-flat surface, 82B-flat end surface, 83-recess,
84-Discharge port, 85-Fluid passage, 86-Fluid inlet port, 9-Control unit,
90-control panel, 91-detection routine, 92-re-holding routine,
93-Work delivery routine

Claims (8)

A holder in which a discharge port is formed on a holding surface facing one surface of the wafer;
An air discharge part for discharging air from the discharge port;
And at least one moving clamper that is movable along a radial direction of the wafer between a contact position that contacts the outer periphery of the wafer and a retracted position that is separated from the outer periphery of the wafer, and each of the rotational positions is different from each other. A plurality of clampers in contact with the outer periphery of the wafer,
A clamper moving unit for positioning the moving clamper at either the contact position or the retracted position;
A clamper rotating unit that integrally rotates the plurality of clampers around a central axis of the wafer;
A sensor for detecting an object to be detected formed on a part of the outer periphery of the wafer;
The wafer is held by the plurality of clampers in a state where the wafer is close to and separated from the holding surface by controlling the amount of air discharged from the air discharge port by the air discharge unit and the position of the moving clamper by the clamper moving unit. And a controller that controls rotation of the plurality of clampers by the clamper rotation unit based on a detection result of the sensor.   The alignment apparatus according to claim 1, further comprising a swirl flow forming body that generates a swirl flow of air at the discharge port. A wafer alignment method for detecting a rotational position of the detected object using the wafer alignment apparatus according to claim 1,
When the wafer is loaded to the position facing the holding surface, the moving clamper is positioned at the retracted position, air is discharged from the discharge port, and the loaded wafer is separated from the holding surface in the state of being separated from the holding surface. A holding step of moving the clamper to the contact position to bring the plurality of clampers into contact with the outer periphery of the wafer;
And a detection step of detecting the detected object by the sensor while rotating the plurality of clampers. When the sensor does not detect the object to be detected in the detection step, the movable clamper is positioned at the retracted position, and the discharge of air from the discharge port is adjusted to place the wafer around the central axis. A re-holding step of rotating the movable clamper to the contact position and rotating the plurality of clampers to the outer periphery of the wafer after rotating by a fixed amount;
The wafer alignment method according to claim 3, wherein the detection step is performed again after the re-holding step. A wafer alignment system comprising the wafer alignment apparatus according to claim 1,
A hand that holds the wafer in contact with or in close proximity from the direction facing the holding surface of the holder;
Hand moving means for moving the hand;
A wafer alignment system comprising: a wafer conveyance device comprising: a conveyance control unit that controls the wafer holding means and the hand moving means so as to carry the wafer into a position facing the holding surface in the wafer alignment apparatus. A wafer alignment method for detecting the position of an object to be detected using the wafer alignment system according to claim 5,
A loading step of moving the hand and holding the wafer held by the hand onto the holding surface of the holder in a state where the moving clamper is positioned in the retracted position in advance;
Air is discharged from the discharge port, and the movable clamper is moved to the contact position in a state in which the carried wafer is separated from the holding surface to bring the plurality of clampers into contact with the outer periphery of the wafer. , A holding step in which the hand does not hold the wafer;
A detection step of detecting the detected object by the sensor while rotating the plurality of clampers;
When the detected object is detected, the hand holds the wafer held by the holder, positions the movable clamper at the retracted position, stops discharging air from the discharge port, And a wafer unloading method of unloading the wafer and unloading the wafer.   When the sensor does not detect the object to be detected in the detection step, the movable clamper is positioned at the retracted position, and the discharge of air from the discharge port is adjusted so that the wafer is rotated around the central axis. The wafer alignment method according to claim 6, further comprising a re-holding step in which the plurality of clampers are brought into contact with the outer periphery of the wafer by moving the movable clamper to the contact position after being rotated by a predetermined amount.   The wafer alignment method according to claim 7, wherein after the carrying-in process, the holding process and the re-holding process are performed while the hand is stopped at a position facing the holding surface in the wafer alignment apparatus.

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