JP5504980B2 - Wafer lift rotation mechanism, stage apparatus, and ion implantation apparatus - Google Patents

Description

  The present invention relates to a wafer lift rotating mechanism having a wafer removing function for removing a wafer from an electrostatic chuck and a twist angle adjusting function for adjusting a twist angle of the wafer, a stage device having the wafer lift rotating mechanism, and an ion implantation apparatus.

  Conventionally, as a mechanism for removing a wafer attracted to an electrostatic chuck in an ion implantation apparatus, as shown in Patent Document 1, a plurality of push-up members inserted into a plurality of through holes formed in the electrostatic chuck, and this And a lifting mechanism that lifts and lowers the push-up member relative to the electrostatic chuck, and a device that forcibly removes the wafer adsorbed on the electrostatic chuck by moving the plurality of push-up members up and down by the lifting mechanism is considered. ing.

  On the other hand, when a wafer is placed on an electrostatic chuck in a conventional ion implantation apparatus, the wafer chuck angle (pre-aligner) disposed on the atmosphere side is adjusted in advance and the wafer chuck angle is adjusted by a transfer robot. It is configured to be conveyed upward.

  In recent years, high accuracy of ion implantation into a wafer has been demanded by users, and it is becoming difficult to meet user requirements only by adjusting the position of the wafer with the wafer aligner as described above. That is, the accuracy of ion implantation into the wafer is hindered by the deviation of the wafer position (specifically, the twist angle) that occurs when the wafer is transferred and placed on the electrostatic chuck.

  For this reason, as shown in Patent Document 2, after the wafer is held on the electrostatic chuck, the twist angle of the wafer attracted to the electrostatic chuck is adjusted by rotating the electrostatic chuck. Things are being considered.

  However, the electrostatic chuck is connected with a power supply cable for imparting polarity to the mounting surface and a refrigerant supply pipe for supplying a coolant into the electrostatic chuck for cooling the mounting surface. Therefore, it is not preferable to rotate the electrostatic chuck frequently from the viewpoint of durability of the power cable and sealing performance of the supply pipe. In addition, particularly from the viewpoint of the durability of the power cable, the angle at which the electrostatic chuck can be rotated is limited.

  Further, since the electrostatic chuck of Patent Document 2 does not have a wafer detachment mechanism, it is relatively easy to provide a rotation mechanism. However, as in Patent Document 1, the electrostatic chuck has a detachment mechanism. If it is a thing, it is necessary to rotate a removal mechanism integrally with an electrostatic chuck. Thus, if these two are rotated simultaneously, it is considered that not only a large rotating mechanism is required, but also the position control of the twist angle of the wafer becomes difficult.

Japanese Patent No. 2920239 JP 2004-95434 A

  Accordingly, the present invention has been made to solve the above problems all at once, and realizes the removal of the wafer from the electrostatic chuck and the adjustment of the twist angle of the wafer placed on the electrostatic chuck with a simple configuration. In addition, the main problem is to make it possible to adjust the twist angle of the wafer without rotating the electrostatic chuck.

That is, the wafer lift rotation mechanism according to the present invention is provided outside the electrostatic chuck plate, contacts the peripheral edge of the wafer extending to the outside, and places the wafer on the electrostatic chuck plate or electrostatic chuck. A lift member for removing the wafer from the plate, a retreat position where the wafer is placed on the electrostatic chuck plate in a non-contact state, and the wafer is held from the electrostatic chuck plate by holding the wafer. An elevating mechanism that raises and lowers the lift member along a direction substantially perpendicular to the electrostatic attraction surface between the separated separation positions, and the lift member is rotated in a state where the lift member is in the separation position holding the wafer. by, comprising a rotating mechanism for adjusting the twist angle of the wafer, this to the lifting mechanism, vertically moving the rotating mechanism in the vertical direction The features.

  If this is the case, the lift member is provided outside the electrostatic chuck plate and moved up and down and rotated with respect to the electrostatic chuck plate. Both adjustments of the twist angle can be performed. Therefore, the twist angle of the wafer can be adjusted without rotating the electrostatic chuck plate, and not only can the life of the power cable connected to the electrostatic chuck plate be extended, but also the electrostatic When the refrigerant supply pipe for supplying the refrigerant to the chuck plate is provided, it is possible to suppress the deterioration of the sealing performance. Furthermore, the configuration in which the lift member that does not require connection of the power cable rotates allows the wafer to be freely rotated without being restricted by the power cable.

  When the wafer is detached from the electrostatic chuck plate, the warp generated on the wafer is reduced as much as possible, and the contact area between the lift member and the peripheral edge of the wafer is increased as much as possible to rotate the lift member. In order to make it difficult for the wafer to slip, it is desirable that the lift member is configured to contact substantially the entire circumference of the peripheral edge of the wafer.

  In order not only to prevent the wafer from falling from the lift member due to the reaction when the wafer is detached from the electrostatic chuck plate, but also to prevent the wafer from falling from the lift member when the lift member is rotated. It is desirable that the lift member has a fall prevention structure for preventing the wafer from falling when holding the wafer.

  The wafer is prevented from being displaced with respect to the lift member when the wafer is held, and the wafer rotation angle and the rotation angle of the lift member are adjusted by matching the center of the wafer with the rotation center of the lift member. In order to match, it is desirable that the lift member has a center adjustment structure that aligns the center of the wafer with the rotation center of the lift member when holding the wafer.

  In order to realize the fall prevention structure and the center adjustment structure with one configuration, it is desirable that the wafer contact surface of the lift member has a tapered surface that narrows in the descending direction.

As a specific arrangement mode of the lift member, the rotation mechanism, and the lifting mechanism, the lift member is rotatably supported and has a pedestal to which the rotation mechanism is fixed, and the lifting mechanism lifts and lowers the pedestal. Therefore, it is desirable that the lift member be moved up and down. At this time, the rotation mechanism fixed on the pedestal can directly rotate and move the lift member, and the rotation position of the lift member can be accurately controlled. The output can be made as small as possible. When the rotation mechanism is arranged in an injection chamber (for example, a vacuum chamber of 10 ⁻⁵ Pa to 10 ⁻⁶ Pa), when a vacuum motor is used as a component of the rotation mechanism, the vacuum motor Since the speed reducer cannot be used, the output torque becomes small. For this reason, it is desirable that only the lift member be rotated. On the other hand, when the reverse structure, that is, when the lift member and the lifting mechanism are provided on the pedestal and the pedestal is rotated by the rotating mechanism, it is necessary to increase the output torque of the rotating mechanism, which is not preferable for the above reason.

  According to the present invention configured as described above, the wafer can be detached from the electrostatic chuck and the twist angle of the wafer placed on the electrostatic chuck can be adjusted with a simple configuration, and the electrostatic chuck can be rotated. In addition, the twist angle of the wafer can be adjusted.

It is a mimetic diagram showing the whole ion implanter composition concerning one embodiment of the present invention. It is a perspective view explaining operation | movement of the ion beam and wafer moving apparatus of the embodiment. It is sectional drawing which shows the wafer lift rotation mechanism of the embodiment. It is a typical top view of the lift main body of the embodiment. It is an expanded sectional view which shows the lift contact surface of the lift member of the embodiment. It is a figure which shows the twist angle of a wafer. It is a schematic diagram which shows the raising / lowering operation | movement of the wafer lift rotation mechanism of the embodiment. It is sectional drawing which shows the wafer lift rotation mechanism which concerns on deformation | transformation embodiment. It is a schematic plan view of a lift member according to a modified embodiment. It is an expanded sectional view of the lift member which concerns on deformation | transformation embodiment.

  Hereinafter, an embodiment of an ion implantation apparatus according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the ion implantation apparatus 100 according to the present embodiment uses the traveling direction of the ion beam IB as the Z direction, and two directions substantially perpendicular to each other in a plane substantially perpendicular to the Z direction are defined as X. When the direction and the Y direction are set, the ion beam IB is scanned in the X direction by an electric field or a magnetic field, whereby a ribbon-like ion beam IB having a ribbon-like shape whose X-direction dimension is larger than the Y-direction dimension The ribbon-like ion beam IB is generated and introduced into the implantation chamber 107, and the wafer W is mechanically reciprocated in the Y direction at the implantation position where the ion beam IB enters the implantation chamber 107. Thus, the ion beam IB is incident on the wafer W to perform ion implantation.

  The wafer W is, for example, a semiconductor substrate such as a silicon substrate, a glass substrate, or another substrate. The planar shape is substantially circular in the present embodiment, but may be a rectangle or other shapes.

  Specifically, as shown in FIG. 1, an ion source 101 that generates an ion beam as a base of a ribbon-shaped beam, and an ion beam of a predetermined ion species from the ion beam emitted from the ion source 101 are used. From the analysis electromagnet 102 that selects and derives the ion beam, the acceleration / deceleration device 103 that accelerates / decelerates the ion beam derived from the analysis electromagnet 102 to a predetermined energy, and the ion beam derived from the acceleration / deceleration device 103 An energy separator 104 that selectively extracts an ion beam having a predetermined energy, a scanner 105 that reciprocally scans the ion beam derived from the energy separator 104 in the X direction by an electric field or a magnetic field, and the scanner 105 A parallel beam scan of the derived ion beam is performed to form an ion beam IB having a ribbon shape. And an encoder 106. The parallel scanning means scanning the ion beam in the X direction while maintaining a state parallel or substantially parallel to the traveling direction Z of the ion beam.

  The ribbon-like ion beam IB derived from the beam collimator 106 is irradiated onto the wafer W held by the wafer holder 2 of the wafer moving device 200 in the implantation chamber 107 evacuated to a vacuum, thereby causing the wafer W to be irradiated. Ion implantation is performed. At this time, the wafer W is reciprocated in the Y direction by the wafer moving device 200 as shown in FIG. By reciprocating the wafer W and irradiating the ribbon-like ion beam IB, ion implantation can be performed on the entire surface of the wafer W. Usually, in order to perform ion implantation on the entire surface of the wafer W, the dimension of the ion beam IB in the X direction is slightly larger than the dimension of the wafer W in the X direction.

  Instead of scanning the ion beam IB in the X direction as described above, an ion beam having a ribbon shape in which the dimension in the X direction is larger than the dimension in the Y direction is generated from the ion source 102. May be transported to the wafer W and incident on the wafer W. In other words, an ion beam having a ribbon shape may be used without scanning in the X direction.

  Next, the wafer moving apparatus 200 that is a stage apparatus in the ion implantation apparatus 100 of the present embodiment will be described.

  As shown in FIG. 2, the wafer moving device 200 holds the wafer W and reciprocates the wafer W in the Y direction. The wafer holder 2 having an electrostatic chuck function and the wafer holder 2 in the Y direction are moved. And a reciprocating mechanism 3 for reciprocating movement.

  As shown in FIG. 3, the wafer holder 2 includes an electrostatic chuck plate 21 that electrostatically attracts and holds the wafer W, and a support member 22 that supports the electrostatic chuck plate 21 is connected to the lower surface thereof. The lower end of the support member 22 is connected to a base member 23 that moves in the Y direction by the reciprocating mechanism 3.

  The wafer holder 2 is configured to be rotatable about the rotation axis 201 at the time of ion implantation and at the time of wafer transfer, and the electrostatic chuck plate is used for ion implantation at the time of ion implantation. The electrostatic attraction surface 21a is rotated by a drive unit (not shown) so as to face in the Z direction. During wafer transfer, the electrostatic attraction surface 21a is vertically upward (in this embodiment, for wafer W transfer). It is rotated by the drive unit so as to face (X direction).

  The electrostatic chuck plate 21 adsorbs the wafer W by an electrostatic force generated by applying a voltage to an internal electrode provided in the insulating layer, and has an approximately flat plate shape whose upper surface becomes an electrostatic adsorption surface 21a. Is. The electrostatic chuck plate 21 has a shape (a circular shape in the present embodiment) that is slightly smaller than the planar shape of the wafer W to be electrostatically attracted, and the wafer W is placed on the electrostatic chuck plate 21. In the mounted (sucked) state, the entire circumference of the peripheral edge Wa of the wafer W protrudes from the outside in the radial direction of the electrostatic chuck plate 21.

  Further, the support member 22 is cooled by a power cable (not shown) for applying a voltage to the internal electrode to impart polarity to the electrostatic chucking surface 21a and the electrostatic chuck plate 21 (particularly the electrostatic chucking surface 21a). There is provided a refrigerant supply pipe (not shown) through which a cooling medium for the purpose flows.

  As shown in FIG. 2, the reciprocating mechanism 3 reciprocates the wafer holder 2 in one direction (Y direction in FIG. 2) in the implantation chamber 107, and the wafer holder 2 is connected to move the wafer holder 2 to Y. The first moving mechanism 31 for reciprocating along the direction and the first moving mechanism 31 are connected, and the first moving mechanism 31 for reciprocating along the Y direction together with the wafer holder 2 is connected. 2 moving mechanisms 32. In the present embodiment, the first moving mechanism 31 and the second moving mechanism 32 use ball screw mechanisms, and the pitch of the ball screws of the first moving mechanism 31 is set to the second moving mechanism 32. By making the pitch smaller than the pitch of the ball screw, the first moving mechanism 31 is set at a lower speed and higher resolution than the second moving mechanism 32. The reciprocating mechanism 3 configured in this way is configured to be rotatable around the X direction in the injection chamber 107 as the rotation center. This makes it possible to adjust the tilt angle, which is the angle formed between the vertical line standing on the wafer W and the ion beam IB.

  Thus, in the wafer moving apparatus 200 of the present embodiment, the wafer W that is attracted and held by the electrostatic chuck plate 21 that is a mounting plate of the wafer holder 2 is detached from the periphery of the wafer holder 2 as shown in FIG. In addition, a wafer lift rotation mechanism 4 for adjusting the twist angle β of the wafer W is provided.

  As shown in FIG. 3, the wafer lift rotation mechanism 4 includes a lift member 41, a rotation mechanism 42 that rotates the lift member 41, and an elevating mechanism 43 that moves the lift member 41 up and down. The wafer lift rotating mechanism 4 is configured to rotate integrally with the wafer holder 2 by the rotating shaft 201 during ion implantation and wafer transfer.

  The lift member 41 is provided on the outer side in the radial direction of the electrostatic chuck plate 21 which is a mounting plate, and comes into contact with the peripheral end Wa of the wafer W extending outward in the radial direction of the electrostatic chuck plate 21. The wafer W is placed on or detached from the electrostatic chuck plate 21.

  The lift member 41 of the present embodiment is provided so as to surround the entire outer circumference in the radial direction of the electrostatic chuck plate 21 having a substantially disc shape, and is formed so as to cover the electrostatic chuck plate 21 from below. 411 and a support cylindrical portion 412 provided concentrically with the center of rotation of the lift main body 411.

  As shown in FIG. 4, the lift main body 411 has a substantially dish-shaped rotating body shape and has an upper opening 411 </ b> A that is slightly larger than the outer diameter of the electrostatic chuck plate 21. In the upper opening 411A, a wafer contact portion 413 that contacts the peripheral edge Wa of the wafer W placed on the electrostatic chuck plate 21 is formed. The wafer contact portion 413 of the present embodiment is configured to contact substantially the entire circumference of the peripheral end portion Wa of the wafer W. That is, the wafer contact portion 413 is formed on the entire circumference of the upper opening 411A. As a result, the contact area between the wafer W and the wafer contact portion 413 can be increased, and slippage in the rotation direction of the wafer W on the wafer body 411 is less likely to occur.

  And the wafer contact surface 413a which is the upper surface of the wafer contact part 413 is a taper surface which diameter-reduces as it goes to a descending direction, as shown in FIG. The peripheral edge Wa (specifically, the lower corner) of the wafer W held by the lift member 41 contacts the tapered surface 413a. The taper surface 413 a has a fall prevention structure that prevents the wafer W from falling from the lift member 41 when the lift member 41 holds the wafer W, and a center that aligns the center of the wafer W with the rotation center of the lift member 41. Functions as an adjustment structure. That is, when the lift member 41 is raised by the elevating mechanism 43, the lower corner of the wafer W comes into contact with the middle part of the tapered surface 413a. Thereby, even if the wafer W jumps upward due to the reaction of separation, the upper portion of the taper surface 413a surrounds the periphery of the wafer W, so that the fall can be prevented. Further, even when the wafer W is inclined when the wafer W is held by the lift member 41, the wafer W can be leveled by sliding along the vertical direction of the taper surface 413a. The center of rotation of the lift body 411 and the center of the wafer W can be matched.

  A cylindrical wall portion 414 having a substantially cylindrical shape is formed on the upper portion of the lift member 41 continuously to the wafer contact portion 413 (see FIG. 5). The inner diameter of the cylindrical wall portion 414 is substantially the same as the inner diameter of the upper end of the tapered surface 413a that is the wafer contact surface. The cylindrical wall portion 414 functions as a fall prevention structure together with the tapered surface 413a.

  As shown in FIG. 3, the support cylindrical portion 412 is continuously formed on the lower surface of the lift main body 413, and a support member 22 that supports the electrostatic chuck plate 21 is provided inside the support cylindrical portion 412. Has been inserted. The support cylindrical portion 412 is inserted into a through hole 44H formed in the base 44 that rotatably supports the lift member 41, and a bearing 45 such as a rolling bearing between the wall portion forming the through hole 44H, 46 is supported. In this embodiment, the case where it fixes to the base 44 via the rolling bearings 45 and 46 at two places up and down is shown. The pedestal 44 is provided with a rotation mechanism 42 for rotating the lift member 41.

  The rotation mechanism 42 adjusts the twist angle β of the wafer W by rotating the lift member 41 while the wafer W is held by the lift member 41 and separated from the electrostatic chuck plate 21. As shown in FIG. 6, the twist angle β is an angle obtained by rotating the wafer W from the reference position around the plane center Wc. In the present embodiment, for example, an orientation flat or notch at a predetermined position is used as a reference. It is an angle rotated from its reference position as a position.

  As shown in FIG. 3, a specific configuration of the rotation mechanism 42 includes a vacuum motor 421 fixed to a pedestal 44, a drive roller 422 connected to a drive shaft 421a of the vacuum motor 421, and a lift member. A driven roller 423 provided on the outer peripheral surface of the support cylindrical portion 412, and an endless belt 424 that transmits drive from the driving roller 422 to the driven roller 423.

  The rotation of the vacuum motor 421 is controlled by the control device 108. Specifically, the control device 108 acquires an image of the wafer W held by the lift member 41 by an imaging unit (not shown), and the position of the orientation flat or notch of the wafer W in the image of the wafer W is set in advance. The output to the vacuum roller 421 is adjusted by comparing with the reference position of the orientation flat or notch. In this way, the twist angle β of the wafer W held by the lift member 41 is adjusted by the rotation mechanism 42.

  As shown in FIGS. 3 and 7, the elevating mechanism 43 holds the retraction position P that is not in contact with the wafer W while the wafer W is placed on the electrostatic chuck plate 21, and the wafer W. The lift member 41 is moved up and down along a direction (specifically, a vertical direction) substantially perpendicular to the electrostatic chucking surface 21a between the wafer W and a separation position Q separated upward from the electrostatic chuck plate 21. It is. When the wafer W is removed by the elevating mechanism 43, the wafer holder 2 is rotated about the rotation shaft 201 so that the electrostatic chucking surface 21a is vertically upward (coincided with upward in the X direction). ing.

  Specifically, the elevating mechanism 43 is provided between the pedestal 44 provided with the lift member 41 and the rotation mechanism 42 and the reciprocating mechanism 3, and the pedestal 44 is arranged in the vertical direction with respect to the reciprocating mechanism 3. The lift member 41 is moved up and down between the retracted position P and the separated position Q as shown in FIG.

  In the retracted position P, the wafer contact portion 413 of the lift member 41 is separated downward from the lower surface of the peripheral end portion Wa of the wafer W attracted to the electrostatic chuck plate 21 and does not contact the peripheral end portion Wa of the wafer W. Position (see FIG. 7A). In the separation position Q, the lift member 41 holds the wafer W, the wafer W is separated upward from the upper surface (electrostatic chucking surface 21a) of the electrostatic chuck plate 21, and the wafer W is electrostatic chucked. It is a position which does not contact the plate 21 (refer FIG.7 (B)). As a specific configuration of the lifting mechanism 43, one using a vacuum cylinder as an actuator, one using a vacuum motor and a rack and pinion mechanism, and the like are conceivable. These actuators are fixed to a base member 23 slidably provided on the reciprocating mechanism 3.

  The stroke of the actuator of the lifting mechanism 43 is controlled by the control device 108. Specifically, the control device 108 controls an actuator such as a vacuum cylinder that constitutes the lifting mechanism 43 before the wafer W is transferred to the electrostatic chuck plate 21 by a transfer robot (not shown), thereby moving the lift member 41. Raised and moved to the separation position Q. When the transfer robot detects that the wafer W is placed on the lift member 41 (see FIG. 7B), the lift member is controlled by controlling an actuator such as a vacuum cylinder that constitutes the lifting mechanism 43. 41 is lowered to transfer the wafer W from the lift member 41 to the electrostatic chuck plate 21 (see FIG. 7A). Thereafter, when it is detected that the ion implantation has been completed, the control device 108 controls the actuator to raise the lift member 41 and detach the wafer W from the electrostatic chuck plate 21.

  Next, procedures for placing and removing the wafer W in the ion implantation apparatus 100 of the present embodiment will be described.

  First, the wafer W is transferred into the implantation chamber 107 by the transfer robot. At this time, the position of the wafer W held by the transfer robot may or may not be adjusted in advance by a wafer aligner outside the implantation chamber 107. Further, the wafer holder 2 has its electrostatic attraction surface 21a facing vertically upward.

  During the transfer of the wafer W, the lift member 41 in the wafer lift rotation mechanism 4 is positioned at the separation position Q by the elevating mechanism 43. Then, the wafer W is placed on the lift member 41 at the separation position Q by the transfer robot. At this time, the wafer W on the lift member 41 is imaged by the imaging unit, and it is determined whether or not the twist angle β of the wafer W is a desired twist angle. This determination is configured such that the control device 108 automatically performs this determination based on a desired angle input in advance by the user. In addition, you may make it perform visually by a user.

  When the control device 108 determines that the twist angle β of the wafer W on the lift member 41 is not a desired angle by the above comparison, the control device 108 determines the rotation mechanism 42 based on the deviation amount so as to eliminate the deviation. The rotation angle of the vacuum motor 421 is controlled. The twist angle β of the wafer W on the lift member 41 is adjusted by the control of the rotation mechanism 42. After the adjustment, the imaging unit captures the wafer W again, and the comparison and adjustment are repeated in the same manner as described above until the twist angle β of the wafer W reaches a desired angle.

  After the twist angle β of the wafer W is adjusted to a desired angle, the control device 108 controls the actuator of the elevating mechanism 43 to lower the lift member 41 and move the wafer W onto the electrostatic chuck plate 21. Included. After the transfer onto the electrostatic chuck plate 21, the imaging unit captures an image of the wafer W and determines whether or not the twist angle β is a desired angle. If not, the control device 108 uses the lifting mechanism 43. Then, the wafer W is held on the lift member 41, and the twist angle β of the wafer W is adjusted again using the rotation mechanism 42.

  When the twist angle β of the wafer W placed on the electrostatic chuck plate 21 is a desired angle, the control device 108 applies a voltage to the internal electrode of the electrostatic chuck plate 21 via the power cable, and thereby the wafer. The surface of the wafer W is rotated so as to face the Z direction by electrostatically adsorbing W and rotating the wafer holder 2 or the like. Thereafter, the control device 108 controls the other mechanisms of the ion implantation apparatus 100 to introduce the ribbon-like ion beam IB into the implantation chamber 107 and the reciprocation mechanism 3 to move the wafer W in the Y direction. The ions are implanted into the entire surface of the wafer W by reciprocally moving them.

  After the ion implantation, the control device 108 stops the introduction of the ribbon-like ion beam IB and rotates the wafer holder 2 and the like so that the surface of the wafer W faces the X direction. Thereafter, the application of the voltage to the internal electrode is stopped, and the electrostatic chucking of the electrostatic chuck plate 21 is stopped. Then, by controlling the lifting mechanism 43, the lift member 41 is raised and the wafer W is detached from the electrostatic chuck plate 21. After the separation, the wafer W held on the lift member 41 is carried out of the implantation chamber 107 by the transfer robot. Instead of being immediately carried out by the transfer robot after the ion implantation, the lift member 41 at the separation position Q is rotated by a predetermined angle by the rotation mechanism 42 to change the twist angle β of the wafer W and ion implantation is performed again. Processing may be performed.

<Effect of this embodiment>
According to the ion implantation apparatus 100 according to the present embodiment configured as described above, the lift member 41 is provided outside the electrostatic chuck plate 21 and is simply moved up and down and rotated with respect to the electrostatic chuck plate 21. Thus, both removal of the wafer W and adjustment of the twist angle β can be performed via the common lift member 41.

  Further, the twist angle β of the wafer W can be adjusted by rotating the lift member 41 that does not need to be provided with the power cable and the refrigerant supply pipe, so the twist angle β of the wafer W can be adjusted without rotating the electrostatic chuck plate 21. In addition to extending the service life of the power cable connected to the electrostatic chuck plate 21, if the electrostatic chuck plate 21 is provided with a coolant supply pipe, It is also possible to suppress deterioration in sealing performance.

  When the electrostatic chuck plate 21 is rotated, the rotation angle is particularly limited by the power cable, but the wafer W can be freely moved without being limited by the power cable by the configuration in which the lift member 41 is rotated. Can be rotated.

<Other modified embodiments>
The present invention is not limited to the above embodiment.

  For example, the wafer moving apparatus of the above embodiment has a configuration in which the electrostatic chuck plate does not rotate and only the lift member rotates. However, not only the lift member but also the electrostatic chuck plate may be rotated. . In this case, in addition to the lift rotation mechanism that rotates the lift member, a chuck rotation mechanism that rotates the electrostatic chuck plate is provided. This chuck rotating mechanism can be considered to rotate the electrostatic chuck plate by rotating the supporting member of the electrostatic chuck plate. The chuck rotating mechanism needs to be rotated within a range that takes into account the durability of the power cable.

  Further, the lift member 41 of the above embodiment is configured by a lift main body 411 and its supporting cylindrical portion 412 provided outside in the radial direction of the electrostatic chuck plate 21. As shown in FIG. The lift pin 47 may be provided coaxially with the rotation center of the plate 21. By providing the lift pins 47 in this way, it is possible to eliminate the warpage that occurs in the center of the wafer when only the peripheral edge Wa of the wafer W is supported, and to reduce the warpage of the entire wafer. Further, since the lift pin 47 is provided at the rotation center of the electrostatic chuck plate 21, it is not necessary to rotate the electrostatic chuck plate 21 even when the lift pin 47 is rotated together with the lift body 411. Further, even when the electrostatic chuck plate 21 is rotated in the case where the lift pins 47 are not rotated, the lift pins 47 do not hinder the rotation of the electrostatic chuck plate 21.

  Furthermore, the wafer contact portion 413 of the above embodiment is provided on the entire inner peripheral surface of the lift body 411 so as to contact the entire circumference of the peripheral end portion Wa of the wafer W. In addition, as shown in FIG. In addition, a plurality of wafer contact portions 413 may be provided intermittently in the circumferential direction.

  In addition, the wafer contact surface 413a of the lift member 41 of the above-described embodiment is a tapered surface. However, as shown in FIG. As the protruding ridge portion, the wafer contact surface 413a may be formed by a horizontal surface which is the upper surface thereof. Moreover, you may form in the inner peripheral surface of the lift main body 411 by the some protrusion upper surface protruded to the internal diameter side.

  In addition, the ion implantation apparatus of the embodiment irradiates the wafer with a ribbon-like ion beam. The spot-like ion beam is scanned in parallel in the X direction by scanning means using an electric field or a magnetic field. A configuration in which a wafer holder holding a wafer to be implanted is mechanically scanned in a Y direction (for example, a vertical direction) substantially orthogonal to the X direction (for example, a horizontal direction) within a scanning region of an ion beam by a wafer driving mechanism. May be.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Ion implantation apparatus W ... Wafer Wa ... Peripheral edge part 21 ... Electrostatic chuck plate 4 ... Wafer lift rotation mechanism 41 ... Lift member 413a ... Wafer contact surface (taper surface) )
42 ・ ・ ・ Rotating mechanism 43 ・ ・ ・ Elevating mechanism 44 ・ ・ ・ Pedestal P ・ ・ ・ Retraction position Q ・ ・ ・ Separation position β ・ ・ ・ Twist angle

Claims (8)

A lift member provided on the outer side of the electrostatic chuck plate, for contacting the peripheral edge of the wafer extending outside the electrostatic chuck plate, for placing the wafer on the electrostatic chuck plate or for removing the wafer from the electrostatic chuck plate When,
The lift member between a retracted position that is not in contact with the wafer while the wafer is placed on the electrostatic chuck plate and a spaced position where the wafer is held and separated from the electrostatic chuck plate. Elevating mechanism for elevating and lowering along a direction substantially perpendicular to the electrostatic adsorption surface;
A rotation mechanism that adjusts the twist angle of the wafer by rotating the lift member in a state where the lift member is in a separated position that holds the wafer ;
A wafer lift rotating mechanism in which the lifting mechanism moves the rotating mechanism up and down along a vertical direction .   The wafer lift rotation mechanism according to claim 1, wherein the lift member is configured to contact substantially the entire circumference of the peripheral end portion of the wafer.   The wafer lift rotation mechanism according to claim 1, wherein the lift member has a fall prevention structure that prevents the wafer from falling when the wafer is held.   4. The wafer lift rotation mechanism according to claim 1, wherein the lift member has a center adjustment structure that aligns the center of the wafer with the rotation center of the lift member when holding the wafer.   The wafer lift rotation mechanism according to claim 3 or 4, wherein the wafer contact surface of the lift member has a tapered surface that narrows in a descending direction. The lift member is rotatably supported and has a pedestal to which the rotation mechanism is fixed.
6. The wafer lift rotation mechanism according to claim 1, wherein the lift mechanism moves the lift member up and down by moving the pedestal up and down.   A stage apparatus comprising the wafer lift rotation mechanism according to claim 1. An ion implantation apparatus comprising the wafer lift rotation mechanism according to claim 1.