JP4020124B2 - Ion beam irradiation equipment - Google Patents

Description

  The present invention relates to an ion beam irradiation apparatus configured to irradiate, for example, an ion beam scanned in a horizontal direction onto a substrate held by a holder, and in particular, transports a substrate held by a holder without increasing the size of the irradiation apparatus. It relates to the means to make possible. This ion beam irradiation apparatus is, for example, an ion implantation apparatus.

  In this type of conventional ion beam irradiation apparatus, FIG. 4 is a schematic plan view showing an example of a configuration in which an ion beam is irradiated onto a substrate held by a holder, and the tilt angle of the ion beam irradiation apparatus shown in FIG. FIG. 5 shows a schematic side view when the angle is made larger than 0 degree.

  In FIG. 4, the ion beam 100 is scanned in the X direction (for example, the horizontal direction) by an electric field or a magnetic field. The ion beam 100 scanned in the X direction is irradiated toward the Z direction substantially intersecting the X direction. In this example, the Z direction is also the horizontal direction.

  In this ion beam irradiation apparatus, a front Faraday unit 62, a holder 2, and a back Faraday 64 are arranged in order from the upstream side in the direction Z in which the ion beam 100 is irradiated. Note that an ion beam irradiation apparatus in which a front Faraday unit, a holder, and a back Faraday are arranged in this order is described in FIG.

  The front Faraday unit 62 and the back Faraday 64 are used for measuring the ion beam 100, shaping the scanning waveform of the ion beam 100, and the like.

  The holder 2 holds a substrate 90 that is an object to be irradiated. At this time, the surface 90a of the substrate intersects the irradiation direction Z of the ion beam 100 at a predetermined angle θ (see FIG. 5). In this specification, this crossing angle θ is referred to as a tilt angle θ. The holder 2 is an electrostatic chuck, for example.

  In addition, this ion beam irradiation apparatus includes a holder driving device 4 for driving the holder 2, and a vacuum chamber for storing devices such as the holder 2, the holder driving device 4, the front Faraday unit 62, and the back Faraday 64 in a vacuum region. 80.

  The holder driving device 4 rotates the scanning mechanism 6 that drives the holder 2 so that the substrate 90 held by the holder 2 is scanned with respect to the ion beam 100, and the orientation flat angle of the substrate 90 held by the holder 2. And a tilt mechanism 32 capable of changing the tilt angle θ.

  The “orientation flat angle” refers to an angle formed by an orientation flat (that is, a notch, not shown) formed on the substrate 90 with respect to a predetermined direction.

  The scanning mechanism 6 includes an arm 8 and a reversible arm turning motor 12. The arm 8 is attached to the holder 2 so that it can rotate freely (that is, the orientation flat angle can be changed) at one end 8a, and the scanning shaft 10 is fixedly attached to the other end 8b. The arm turning motor 12 is rotatable around a motor drive shaft 13 substantially parallel to the scanning shaft 10.

  The scanning axis 10 is away from the center O of the holder 2 and is substantially orthogonal to the X direction. That is, the scanning axis 10 is arranged on a plane including an axis parallel to the Y direction and an axis parallel to the Z direction, and does not include the center O of the substrate 90. Here, the Y direction is a direction substantially orthogonal to both the X direction and the Z direction.

  A pulley 14 is fixedly attached to the motor drive shaft 13, and a pulley 16 is fixedly attached to the scanning shaft 10. The pulley 14 and the pulley 16 are arranged in parallel to each other in the X direction, and a timing belt 18 is wound around the pulleys 14 and 16.

  The twist mechanism 20 is a mechanism that changes the orientation flat angle, and includes a reversible twist motor 22, a main shaft 24, pulleys 26 and 28, and a timing belt 30.

  The twist motor 22 is coupled to a main shaft 24 that is disposed coaxially with the scanning shaft 10. The main shaft 24 is inserted in the pulley 16 so as to be rotatable.

  The pulley 26 is fixedly attached to the main shaft 24, and the pulley 28 is fixedly attached to the rotating shaft 29 of the holder 2. The diameter of the pulley 26 and the diameter of the pulley 28 are substantially the same, and the timing belt 30 is wound between the pulley 26 and the pulley 28.

  At least the arm turning motor 12, the motor drive shaft 13, the pulley 14, the pulley 16, and the timing belt 18 are accommodated in the housing 31. The scanning shaft 10 is rotatable with respect to the housing 31.

  The tilt mechanism 32 is fixedly attached to the housing 31 and has a tilt shaft 34 substantially parallel to the X direction, and a reversible tilt motor connected to the tilt shaft 34 concentrically with the tilt shaft 34. 36 and a housing 38 that houses the tilt motor 36.

  The center (hereinafter referred to as “tilt center”) L of the tilt axis 34 is the surface 90 a of the substrate 90, more specifically, the surface 90 a of the substrate 90 and passes through the center O of the substrate 90. That is, when the tilt motor 36 rotates, the tilt angle θ shown in FIG. 5 changes.

  When the substrate 90 is irradiated with the ion beam 100 for processing, the tilt angle θ is changed at a position where the ion beam 100 and the tilt center L coincide with the Z direction. Accordingly, the distance x in the Z direction from an arbitrary point on the path of the ion beam 100 to the tilt center L is constant regardless of the magnitude of the tilt angle θ.

  Next, operations of the scanning mechanism 6, the twist mechanism 20, and the tilt mechanism 32 will be described with reference to FIGS.

  First, the operation of the scanning mechanism 6 will be described.

  In FIG. 4, when the arm turning motor 12 is rotated within a range of a predetermined angle about the motor drive shaft 13, the pulley 14 is rotated accordingly. Since the timing belt 18 is wound between the pulley 14 and the pulley 16, the pulley 16 rotates as the pulley 14 rotates. When the pulley 16 rotates, the arm 8 rotates because the scanning shaft 10 and the arm 8 are fixedly attached to each other.

  That is, when the arm turning motor 12 rotates around the motor drive shaft 13 within a predetermined angle range, the arm 8 turns around the scanning shaft 10. As a result, the substrate 90 rotates around the scanning axis 10. In other words, the scanning mechanism 6 reciprocates the arm 8 within a predetermined angle range about the scanning axis 10. In this case, the positions that can be taken by the holder 2 and the substrate 90 held by the holder 2 are shown by two-dot chain lines in FIG.

  Next, the operation of the twist mechanism 20 will be described. In FIG. 4, when the twist motor 22 rotates, the main shaft 24 and the pulley 26 rotate accordingly. Here, since the timing belt 30 is wound between the pulley 26 and the pulley 28, the timing belt 30, the pulley 28, and the holder 2 rotate in the same direction as the rotation direction of the twist motor 22.

  In this way, the orientation flat angle is set to a predetermined angle by rotationally driving the twist motor 22.

  By the way, this ion beam irradiation apparatus is configured such that the orientation flat angle is constant even when the scanning mechanism 6 reciprocally turns the arm 8 within a predetermined angle range about the scanning axis 10. Yes.

  That is, when the arm 8 is rotated clockwise by φ degrees as viewed in the Z direction by the arm turning motor 12, for example, when viewed from the arm 8 side, the pulley 26 is rotated counterclockwise by φ degrees.

  At this time, the pulley 28 around which the timing belt 30 is wound around the pulley 26 rotates φ degrees counterclockwise when viewed from the arm 8 side. This is because the diameter of the pulley 26 and the diameter of the pulley 28 are substantially the same.

  Therefore, the holder 2 is scanned so as to draw an arc with the length of the arm 8 as a radius around the scanning axis 10 as a rotation center, but the orientation flat angle is not changed and its posture is unchanged. Therefore, the posture of the substrate 90 held by the holder 2 is also constant.

  Finally, the operation of the tilt mechanism 32 will be described. 4 and 5, when the tilt motor 36 rotates about the tilt center L, the substrate 90 rotates as the tilt motor 36 rotates. This is because the tilt motor 36 and the holder 2 are connected via the tilt shaft 34, the housing 31, the scanning shaft 10 and the arm 8.

  Here, since the tilt center L passes through the surface 90a of the substrate 90, the substrate 90 rotates about the tilt center L. That is, this means that the tilt angle θ changes as the tilt motor 36 rotates.

  In this way, the desired orientation flat angle and tilt angle θ are set, and the ion beam 100 scanned in the X direction is irradiated onto the substrate 90 held by the holder 2. Further, the arm 8 is reciprocated within a predetermined angle range around the scanning axis 10 to irradiate the entire surface of the substrate 90 with the ion beam 100 to perform a series of processes such as ion implantation.

  In this way, even when the ion beam 100 is irradiated over the entire surface of the substrate 90 by reciprocatingly turning the arm 8 within a predetermined angle range around the scanning axis 10, the path of the ion beam 100. The distance x in the Z direction from the arbitrary point above to the tilt center L is always constant.

  When a series of processing is completed by irradiating the surface 90a of the substrate 90 with the ion beam, the tilt motor 36 rotates about the tilt center L until the holder 2 (that is, the substrate 90) becomes substantially horizontal.

  On the other hand, as illustrated in FIG. 5, a transport device 65 for transporting the substrate 90 before and after the processing is disposed on the Z direction side from the back Faraday 64.

  The transfer device 65 includes a transfer arm 66 that turns in a horizontal direction with a predetermined point (not shown) as a fulcrum, and a substrate receiver 68 attached to the transfer arm 66. Then, the transport arm 66 pivots in the horizontal direction with a predetermined point (not shown) as a fulcrum, so that the substrate 90 after a series of processing is supported by the substrate receiver 68 and transported. Similarly, the unprocessed substrate 90 can be transferred to the holder 2.

  However, in the configuration illustrated in FIG. 5, the back Faraday 64 is disposed between the substrate 90 and the transfer device 65. Accordingly, even if the holder 2 is brought into a substantially horizontal state by the tilt motor 36, if the transport arm 66 is turned, it interferes with the back Faraday 64, and the substrate 90 can be transported (delivered) to the holder 2. Can not.

  Further, since the back Faraday 64 is used for the measurement of the ion beam 100 as described above, it is not preferable to move the back Faraday 64 in the Y direction for reasons such as deterioration in measurement accuracy.

  Furthermore, the back Faraday 64 is an example of the one disposed between the holder 2 and the transfer device 65, and in addition to the back Faraday 64, other structures such as measuring instruments are often disposed.

  As one measure for solving the above problems, for example, a configuration similar to that shown in FIG. This case will be described with reference to FIG. FIG. 6 is a schematic plan view of the ion beam irradiation apparatus shown in FIGS. 4 and 5 when the holder 2 is movable to the Z direction side from the back Faraday 64.

  In FIG. 6, when a series of processing is completed for the substrate 90, the arm turning motor 12 rotates. As a result, the arm 8 pivots upward, for example, with the scanning axis 10 as the center of rotation. That is, when viewed in the direction opposite to the Z direction, the arm 8 pivots counterclockwise around the scanning axis 10 as a rotation center.

  When the tilt motor 36 is rotated after the arm 8 rotates about 90 degrees about the scanning axis 10, the arm 8 rotates about the tilt axis 34. Thereby, the holder 2 can be positioned in the region G on the Z direction side with respect to the back Faraday 64.

JP 2001-143651 A (FIG. 1) Japanese Patent No. 2797368 (FIG. 1)

  However, when the arm 8 is turned about the scanning axis 10 and then the arm 8 is turned about the tilt axis 34 so that the holder 2 is positioned on the Z direction side of the back Faraday 64, the back Faraday An area G in which the holder 2 can stand by is required on the Z direction side from 64, and there is a problem that the apparatus is increased in size.

  In view of the above, the main object of the present invention is to provide an ion beam irradiation apparatus that can easily transport a substrate in a horizontal state while avoiding an increase in size of the apparatus.

  A substrate holding apparatus according to the present invention for solving the above-described problems is an ion beam irradiation apparatus configured to irradiate a substrate held by a holder with an ion beam scanned in the X direction, and includes an arm that supports the holder. A scanning mechanism that reciprocates within a predetermined angular range around a scanning axis that is away from the center of the holder and substantially orthogonal to the X direction, and the surface of the substrate held by the holder A holder driving device having a tilt mechanism that rotates about a tilt axis that is substantially parallel to the X direction and a lifting device that raises and lowers the holder driving device in the Y direction substantially orthogonal to the X direction. It is characterized by providing.

  According to the above configuration, the holder (that is, the substrate) is made substantially horizontal by turning the arm around the tilt axis, and then the holder is moved in the Y direction while the horizontal state of the holder is maintained by the lifting device. It can be moved.

  According to the first aspect of the present invention, since the holder can be moved in the Y direction while maintaining the horizontal state of the holder, a structure such as a back Faraday is disposed between the holder and the transport device. Even if it is a case, the board | substrate hold | maintained at the holder can be conveyed easily, without enlarging an apparatus.

  FIG. 1 is a schematic rear view of an example of an ion beam irradiation apparatus according to the present invention viewed from the direction opposite to the Z direction. FIG. 2 is a schematic plan view of the ion beam irradiation apparatus shown in FIG.

  In the following, the same or corresponding parts as those in the conventional example shown in FIGS. 4 to 6 are denoted by the same reference numerals, and differences from the conventional example will be mainly described.

  1 and 2, the ion beam irradiation apparatus includes a vacuum chamber 80a instead of the vacuum chamber 80 of the conventional ion beam irradiation apparatus. In addition, an elevating device 40 that elevates and lowers the holder driving device in the Y direction is provided.

  The vacuum chamber 80a forms a rectangular region 82 (see FIG. 1) surrounding the tilt mechanism 32. That is, the vacuum chamber 80a has a protruding portion 84 that protrudes outward in the X direction.

  In FIG. 1, the lifting device 40 includes the holder 2, the scanning mechanism 6, the twist mechanism 20, and the tilt disposed in the vacuum chamber 80 a by a reversible lifting motor 44 provided outside the vacuum chamber 80 a. It is a device for raising and lowering the mechanism 32 in the Y direction.

  The lifting / lowering motor 44 is fixedly attached to the vacuum chamber 80a and rotates around a connecting shaft 46 that is long in the Y direction.

  A ball screw 48 is fixedly attached to the connecting shaft 46 so as to be concentric with the center M of the connecting shaft 46. Further, a ball nut 50 fixed to the plate 42 is attached to the ball screw 48 on the side opposite to the side on which the connecting shaft 46 is attached. The surface 42 a of the plate 42 is substantially orthogonal to the center M of the ball screw 48.

  A lifting shaft 56 extending in parallel with the ball screw 48 is fixedly attached to the plate 42. The lifting shaft 56 penetrates the protrusion 84 of the vacuum chamber 80a in the Y direction, and is supported by an upper guide 52 and a lower guide 54 fixed to the vacuum chamber 80a outside the vacuum chamber 80a.

  The tilt mechanism 32 is fixedly attached to the lifting shaft 56 in a rectangular region 82 of the vacuum chamber 80a. More specifically, a housing 38 that houses the tilt motor 36 is fixedly attached to the lifting shaft 56.

  Two through holes 86 and 88 are formed in the projecting portion 84 of the vacuum chamber 80a as the elevating shaft 56 penetrates in the Y direction. In order to maintain the vacuum in the vacuum chamber 80a, vacuum seal means 58 and 60 are provided between the tilt motor 36 and the through holes 86 and 88, respectively. That is, these vacuum sealing means 58 and 60 have a function of sealing between the outer region and the inner region of the vacuum chamber 80a. Note that the vacuum sealing means 58 and 60 are formed of bellows in this example, and can be expanded and contracted in the Y direction.

  Next, the operation of the lifting device 40 will be described.

  In FIG. 1, when the elevating motor 44 is rotated, the connecting shaft 46 and the ball screw 48 are rotated with the center M as the rotation center. At this time, the position of the elevating motor 44, the connecting shaft 46, and the ball screw 48 is unchanged with respect to the vacuum chamber 80a. This is because the elevating motor 44 is fixed to the vacuum chamber 80a.

  When the ball screw 48 rotates in any one direction (for example, clockwise) with the center M as the rotation center, the ball nut 50 and the plate 42 are raised. Further, when the ball screw 48 rotates in the other direction (for example, counterclockwise) with the center M as the rotation center, the ball nut 50 and the plate 42 are lowered.

  Thus, when the plate 42 moves up and down in the Y direction, the lifting shaft 56 fixed to the plate 42 and the tilt mechanism 32 fixed to the lifting shaft 56 move up and down in the Y direction. Since the vacuum seal means 58 and 60 are formed of bellows, the seal between the outer region and the inner region of the vacuum chamber 80a is held even when the tilt mechanism 32 is moved up and down in the Y direction. Is possible.

  Next, an operation for transporting the substrate 90 after a series of processes will be described with reference to FIG. 3A and 3B are schematic views in which the substrate 90 held by the holder 2 is transported by the transport device 65, where FIG. 3A is a plan view and FIG. 3B is a side view.

  As shown in FIG. 3A, in the transfer device 65, the transfer arm 66 turns around a predetermined position (not shown) as a fulcrum (see arrow A).

  When a series of processing is completed by irradiating the surface 90a of the substrate 90 with the ion beam 100, the holder 2 (as shown by a two-dot chain line in FIG. 3B is rotated by rotating the tilt motor 36. That is, the substrate 90) is substantially horizontal.

  In FIG. 3 (b), the holder 2 which is in a substantially horizontal state is lowered by the elevating device 40 and is in a state illustrated by a solid line (see arrow B). At this time, as the holder 2 is lowered, the arm 8 (see FIG. 1) supporting the holder 2 is also lowered, so that the holder 2 is lowered by the lifting device 40 while maintaining a substantially horizontal state.

  Further, the elevating device 40 can be lowered until the holder 2 is positioned below the virtual line N parallel to the Z direction passing through the lowermost end 64a of the back Faraday 64. Thereby, the transfer arm 66 constituting the transfer device 65 arranged on the Z direction side from the back Faraday 64 can transfer the substrate 90 held by the holder 2 without interfering with the back Faraday 64. Become. Similarly, the unprocessed substrate 90 can be transferred to the holder 2.

  Accordingly, since it is not necessary to provide the region G shown in FIG. 6 on the Z direction side with respect to the back Faraday 64, the substrate 90 held by the holder 2 can be easily transported without increasing the size of the ion beam irradiation apparatus. can do.

  In the above-described embodiment, the lifting device 40 lowers the holder 2 until the holder 2 is positioned below the imaginary line N, but instead, the holder 2 may be raised. . In this case, it is necessary to raise the holder 2 until it is positioned above a virtual line K parallel to the Z direction passing through the uppermost end 64b of the back Faraday 64. However, from the standpoint of the user using this ion beam irradiation apparatus, it is often preferable to lower the holder 2 until the holder 2 is positioned below the virtual line N. This is because if the transfer line of the substrate 90 in the ion beam irradiation apparatus is increased, it is necessary to increase the transfer line of equipment used in the pre-process and the post-process of the ion beam irradiation apparatus.

It is the schematic rear view which looked at an example of the ion beam irradiation apparatus concerning this invention from the direction opposite to the Z direction. FIG. 2 is a schematic plan view of the ion beam irradiation apparatus illustrated in FIG. 1. FIG. 6 is a schematic view of the substrate 90 held by the holder 2 being transported by the transport device 65, where (a) is a plan view and (b) is a side view. In the conventional ion beam irradiation apparatus, it is a schematic plan view which shows an example of the structure by which an ion beam is irradiated to the board | substrate hold | maintained at the holder. FIG. 5 is a schematic side view when the tilt angle θ of the ion beam irradiation apparatus shown in FIG. 4 is made larger than 0 degree. FIG. 6 is a schematic plan view of the ion beam irradiation apparatus illustrated in FIGS. 4 and 5 when the holder is movable in the Z direction side from the back Faraday.

Explanation of symbols

2 Holder 4 Holder Drive Device 6 Scanning Mechanism 8 Arm 10 Scanning Axis 32 Tilt Mechanism 34 Tilt Axis 40 Lifting Device 90 Substrate 90a Substrate Surface 100 Ion Beam

Claims (1)

An ion beam irradiation apparatus configured to irradiate a substrate held by a holder with an ion beam scanned in the X direction,
A scanning mechanism for reciprocatingly swinging an arm supporting the holder within a predetermined angular range around a scanning axis that is away from the center of the holder and substantially perpendicular to the X direction, and the scanning mechanism A holder driving device having a tilt mechanism that rotates about a tilt axis that passes through the surface of the held substrate and is substantially parallel to the X direction;
An ion beam irradiation apparatus comprising: an elevating device that elevates and lowers the holder driving device in a Y direction substantially orthogonal to the X direction.

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