JP4036207B2 - XY stage - Google Patents

Description

  The present invention relates to an XY stage suitable for a wire bonder, and more particularly to an XY stage that prevents vibration due to high-speed movement and improves controllability.

  When connecting a large scale integrated circuit (LSI), which is a semiconductor device, and a lead frame with a gold wire or the like, a wire bonder having an XY stage is used. Such an XY stage is required to be positioned at high speed and with high accuracy, and the residual vibration after driving / stopping is required to be low.

  FIG. 20 is a schematic view showing the structure of a conventional wire bonder stage, and FIG. 21 is a schematic view showing a state in which a bonding head is mounted on the conventional wire bonder stage shown in FIG.

  In the conventional wire bonder stage, two X-axis guides 102 are provided on a square plate-like base 101. The two X-axis guides 102 extend in directions parallel to each other, and this direction is taken as the X-axis direction. An X-axis table 103 is provided on the X-axis guide 102. An X-axis copying portion (not shown) that follows the X-axis guide 102 is formed on the lower surface of the X-axis table 103, and the X-axis table 103 is movable in the X-axis direction. On the other hand, two Y-axis guides 104 extending in the Y-axis direction orthogonal to the X-axis direction are provided on the upper surface of the X-axis table 103. A movable table 105 is provided on the Y-axis guide 104. A Y-axis copying portion (not shown) that follows the Y-axis guide 104 is formed on the lower surface of the movable table 105. The movable table 105 is movable in the Y-axis direction, and the X-axis table 103 and the X-axis The guide 102 can also move in the X-axis direction. The upper surface of the movable table 105 is a flat surface, and the bonding head 110 is fixed thereto.

  Further, an X-axis voice coil motor (hereinafter referred to as a VCM) 106 is arranged on the side of the movable table 105 in the X-axis direction, and a Y-axis VCM 107 is arranged on the side of the Y-axis direction.

  The X-axis VCM 106 is provided with a rectangular cylindrical yoke portion 106c that is fixed to the base and has an opening that penetrates in the lateral direction. An iron core 106d that partitions the opening into two spaces is provided at the intermediate height of the yoke portion 106c. The X-axis VCM 106 is provided with an X-axis mover 106a connected to the movable table 105 and a coil 106b wound around the X-axis mover 106a. The coil 106b is wound so as to surround the iron core 106d. The length of the coil 106b in the horizontal direction is approximately the same as or longer than the movable range of the movable table 105, and the X-axis movable element 106a and the coil 106b can move without being restricted in the Y-axis direction. Magnets are attached to the top and bottom surfaces inside the yoke portion 106c, and a magnetic circuit for forming a magnetic field is formed inside and around the coil 106b.

  Similarly, the Y-axis VCM 107 is provided with a rectangular cylindrical yoke portion 107c having an opening that is fixed to the base and penetrates in the lateral direction. An iron core 107d that partitions the opening into two spaces is provided at the intermediate height of the yoke portion 107c. The Y-axis VCM 107 is provided with a Y-axis mover 107a connected to the movable table 105 and a coil 107b wound around the Y-axis mover 107a. The coil 107b is wound so as to surround the iron core 107d. The length of the coil 107b in the horizontal direction is approximately the same as or longer than the movable range of the movable table 105, and the Y-axis movable element 107a and the coil 107b can move without being restricted in the X-axis direction. Magnets are attached to the top and bottom surfaces inside the yoke portion 107c, and a magnetic circuit for forming a magnetic field is formed inside and around the coil 107b.

  The movable table 105 and the Y-axis movable element 107a constitute an upper stage part 108, and the X-axis table 103 and the X-axis movable element 106a constitute an intermediate stage part 109.

  The mass of the bonding head 110 is larger than that of the upper stage part 108 and the middle stage part 109. For this reason, the overall center of gravity of the bonding head 110, which is a member that can move in the X-axis direction and the Y-axis direction, the upper step portion 108, and the middle step portion 109 is integrated with the integrated bonding head 110 and upper step portion 108 as one member. As a result, the position of the center of gravity of the member substantially coincides.

  In the conventional wire bonder stage configured as described above, the middle stage 109 is guided in the X-axis direction with respect to the base 101 along the X-axis guide 102, and the upper stage 108 is copied along the Y-axis guide 104 along the X-axis table. It is guided in the Y-axis direction with respect to 103 and can also move in the X-axis direction integrally with the middle stage portion 109.

  Further, in such an XY stage that indirectly drives the movable part from the outside via a guide, the position accuracy is assumed to be low, and an XY stage that directly positions the movable table is proposed to solve this drawback. (Japanese Patent Laid-Open No. 1-291194).

  In the XY stage described in this publication, two linear motors are disposed on a base, and the coils of each linear motor are directly connected to the back surface of the movable table. An L-shaped X-axis stage guided in the X-axis direction by the X-axis guide rail and the X-axis linear guide is provided on the same plane as the movable table. A straight line portion of the X-axis stage functions as a Y-axis guide rail, and the movable table is guided in the Y-axis direction by this and the Y-axis linear guide. A planar bearing is provided between the X-axis stage and the movable table and the base. In this way, the movable table is directly driven by the linear motor without passing through the guide.

  Further, an XY stage provided with a link mechanism for holding the movable table in parallel with the base surface in order to speed up the movement has been proposed (Japanese Patent Laid-Open No. 11-148984).

  In the XY stage described in this publication, two VCMs having coils fixed to a movable table are provided. A plurality of links are connected to the movable table, and the movable table surface and the base surface are kept parallel with the movable table floating in the air. With such a configuration, a single table is sufficient, and the XY stage itself can be downsized.

JP-A-1-291194 JP-A-11-148984 Japanese Patent Laid-Open No. 11-8263 JP-A-2-53540

  However, in the conventional wire bonder stage shown in FIGS. 20 and 21, since the mass of the bonding head 110 is large as described above, moment is easily generated during operation, and the guide is required to have rigidity sufficient to withstand the moment. . 22A and 22B are diagrams showing a change in the position of the center of gravity g of the movable part when the bonding head 110 is moved in the Y-axis direction. FIG. 22A is a schematic diagram showing the position before the movement, and FIG. It is a schematic diagram which shows a back position.

  Usually, the bonding head 110 is heavier than the upper step portion 108 and the middle step portion 109, and the total mass of the integrated bonding head 110 and upper step portion 108 is heavier than the middle step portion 109, so that the upper step portion 108 and the bonding head 110 are Y When moving in the axial direction, as shown in FIGS. 22A and 22B, the position of the center of gravity g of the movable portion changes greatly. For this reason, when the X-axis VCM 106 is driven in this state, the driving force acts at a position that is significantly deviated from the center of gravity g of the movable part in plan view. Further, when the movable table 105 is moved in the X-axis direction, the position of the center of gravity g of the movable part changes in relation to the position of the movable table 105 in the Y-axis direction. For this reason, moment force is generated and vibration in the yawing direction is a problem. In the wire bonder, a bonding process is performed immediately after the XY stage is stopped. However, if there is vibration as described above, the positioning accuracy is deteriorated and bonding performance is significantly impaired. Therefore, as described above, the X-axis guide 102 and the Y-axis guide 104 are required to have sufficient rigidity to support the moment load due to the movement of the movable table 105 and the bonding head 110. For this reason, there exists a problem that size reduction of XY stage itself is difficult.

  Further, in the conventional XY stage described in Japanese Patent Laid-Open No. 1-291194, the height of the VCM coil and the height of the movable table are different, so that the driving force from the VCM is applied to the center of gravity of the movable part. Does not work. For this reason, it is difficult to sufficiently suppress the vibration caused by the high-speed movement of the movable stage.

  Furthermore, since the position where the position detector is provided is above the movable table, the position detection accuracy is not sufficient. For this reason, position control may become difficult.

  Furthermore, according to the conventional XY stage described in Japanese Patent Application Laid-Open No. 11-148984, although the intended purpose can be achieved, vibration in the yawing direction caused by high-speed movement of the movable stage is suppressed. It is difficult.

  Further, in these conventional XY stages, vibration in the yawing direction occurs, so that it is necessary to perform feedback control in order to reduce the influence of vibration, and there is a problem that the control band is narrow.

  Further, the members on which the thrust from the X-axis VCM 106 acts include the X-axis table 103, the Y-axis guide 104, the movable table 105, the Y-axis movable element 107a, and the coil 107b of the Y-axis VCM 107. In this case, it is necessary to use a very large VCM for the X-axis VCM 106. For this reason, the inertia of the whole movable part becomes large, and vibration in the yawing direction or the like that resonates at a low frequency is a problem.

  The present invention has been made in view of such problems, and provides an XY stage that can sufficiently suppress vibration after a movable part moves at high speed and can easily control the movement thereof. With the goal.

XY stage according to the present invention, base, a movable table which is movably arranged in the X and Y directions in the XY plane on the base, a working member provided on the movable table, respectively A movable table that includes a stator that is fixed to a base and generates a magnetic field, a mover that is movable relative to the stator, and a coil that is wound around the mover and that is affected by the magnetic field generated by the stator; First and second linear motors that apply driving forces in the X direction and Y direction to the movable table at the same height as the center of gravity of the movable part made of a work member, respectively, and the movable of the first linear motor A first connecting means for connecting the child to the movable table in a state of being movable in the Y direction independently of the movable table; and the movable member of the second linear motor independently from the movable table. And a second coupling means coupled to the movable table in a state movable in the X direction, and the first coupling means is disposed on the upper surface of the movable table so as to extend in the Y direction. A plate-like first cam follower guide and a pair of first cam followers that protrude downward from the end of the mover of the first linear motor and sandwich the first cam follower guide, The two connecting means protrude downward from the end of the movable member of the second linear motor and the plate-like second cam follower guide disposed so as to extend in the X direction on the upper surface of the movable table. And a pair of second cam followers sandwiching the second cam follower guide.

Another XY stage according to the present invention includes a base, a movable table disposed on the base so as to be movable in the X direction and the Y direction within an XY plane, and a working member provided on the movable table. And a movable element that is fixed to the base and generates a magnetic field, a movable element that is movable relative to the stationary element, and a coil that is wound around the movable element and that is affected by the magnetic field generated by the stationary element. First and second linear motors that apply driving force in the X direction and Y direction to the movable table at the same height position as the center of gravity of the movable part composed of the table and the work member, and the first linear motor A first connecting means for connecting the movable element of the second linear motor to the movable table in a state of being movable in the Y direction independently of the movable table, and the movable element of the second linear motor to the movable table. And a second connecting means that is connected to the movable table in a state of being independently movable in the X direction, and the first connecting means is provided on the side surface of one end portion of the movable table in the Y direction. And a first slider provided on an end surface of the mover of the first linear motor and sliding along the first rail, and the second rail. The connecting means includes a second rail provided on the side surface of one end portion in the Y direction of the movable table so as to extend in the X direction, and a second rail provided on an end surface of the movable element of the second linear motor. And a second slider that slides according to the above.

Still another XY stage according to the present invention includes a base, a movable table arranged on the base so as to be movable in the X and Y directions, and a working member provided on the movable table. And a stator that is fixed to the base and generates a magnetic field, a mover that is movable relative to the stator, and a coil that is wound around the mover and that is affected by the magnetic field generated by the stator. A first linear motor and a second linear motor for applying a driving force in the X direction and the Y direction to the movable table at the same height position as the center of gravity of the movable portion comprising the movable table and the working member; A first connecting means for connecting the movable element of the motor to the movable table in a state of being movable in the Y direction independently of the movable table; and the movable element of the second linear motor being connected to the movable table. And a second connecting means for connecting to the movable table in a state of being movable in the X direction, and the first connecting means is provided on an end surface of the mover of the first linear motor. A first rail provided so as to extend in the Y direction; and a first slider provided on a side surface of one end portion in the X direction of the movable table and sliding along the first rail. And a second rail provided on the end face of the movable element of the second linear motor so as to extend in the X direction, and a second rail provided on a side surface of one end portion in the Y direction of the movable table. And a second slider that slides along the rail.

  In the XY stage of the present invention, the working member is, for example, a bonding head and is used for wire bonding.

  Furthermore, the first and second linear motors each have a stator fixed to the base, a mover connected to the movable table, and a coil wound around the mover, A first connecting member that connects the movable element of the first linear motor to the movable table in a state of being movable in the Y direction independently of the movable table; and A second coupling member coupled to the movable table in a state of being movable in the X direction independently of the movable table. In this case, the first connecting member includes two first protrusions fixed to the mover of the first linear motor side by side in the X direction, and the two first protrusions. A first protrusion guide member extending in the Y direction and fixed to the movable table, and the second connecting member is connected to the mover of the second linear motor by the Y Two second protrusions fixed side by side in the direction, and a second protrusion guide extending between the two second protrusions in the X direction and fixed to the movable table And a member. Further, the first connecting member passes between the two first projections fixed in the X direction on the movable table and between the two first projections in the Y direction. A first protrusion guide member extending to the movable element of the first linear motor, and the second connecting member is fixed to the movable table side by side in the Y direction. Second protrusions and a second protrusion guide member that extends between the two second protrusions and extends in the X direction and is fixed to the mover of the second linear motor. And may have. Furthermore, the first and second connecting members may be one type of linear motion guide device selected from the group consisting of a cross roller and a linear guide.

  In the present invention, a first position detector that is arranged on a straight line that passes through the center of gravity in a plan view and extends in the X direction and that detects the amount of movement of the movable part in the X direction, and a path through the center of gravity in a plan view. A second position detector that is disposed on a straight line extending in the Y direction and detects a movement amount of the movable part in the Y direction. Moreover, you may have the position detector which is arrange | positioned in the position of the said gravity center by planar view, and detects the moving amount | distance in the said X direction and the Y direction of the said movable part. In these cases, for example, the position detector may include an optical sensor, and for example, a scale indicating the amount of movement in the X direction and the Y direction is provided on the base surface.

  The linear motor may have a magnetic circuit that forms a magnetic field in the vertical direction in the stator, and the magnetic circuit is arranged so that, for example, at least two poles that are different in the vertical direction face each other. It has a magnet.

  In addition, a feedback control unit that controls the operation of the linear motor based on the amount of movement detected by the position detector may be included, and the linear motor may be an AC linear motor.

  In the present invention, when the movable part is driven by the linear motor, the force from the linear motor acts on the center of gravity of the movable part. For this reason, even if the position of the movable table is shifted in the direction perpendicular to the driving direction, the center of gravity is always driven. Therefore, even if the movable table is moved at a high speed, almost no moment force is generated, and in the yawing direction. Vibration hardly occurs. For this reason, even if a guide member having a rigidity lower than that of the conventional one is used to guide the movable part, stable operation is possible, and thus the weight and size can be reduced. In addition, since the vibration in the yawing direction is suppressed, the controllable frequency band is widened.

  As described above in detail, according to the present invention, since the force from the linear motor acts on the center of gravity of the movable part when the movable part is driven by the linear motor, the position of the movable table is orthogonal to the driving direction. Even if it deviates in the direction, the center of gravity can always be driven. For this reason, even if the movable table is moved at high speed, almost no moment force is generated, and vibration due to high speed movement can be prevented. Further, since vibration in the yawing direction can be suppressed, a controllable frequency band can be expanded and controllability can be improved.

  Furthermore, even if a guide member having lower rigidity than the conventional one is used to guide the movable part, stable operation is possible, so that the XY stage itself can be reduced in weight and size.

In particular, according to the present invention, since the movable portion and the mover of the linear motor of both axes can be moved independently, the redundancy (room for movement) can be reduced and the thrust acts. The number of members to be reduced can be reduced. For this reason, a linear motor can be reduced in size. Therefore, since the inertia of the movable part is reduced and the natural frequency is increased, vibration can be suppressed more easily.

Hereinafter, a wire bonder stage according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a schematic view showing a structure of a wire bonder stage according to a reference example of the present invention, and FIG. 2 is a schematic view showing a state in which a bonding head is mounted on the wire bonder stage shown in FIG.

In this reference example , for example, two X-axis guides (first guide members) 2 are provided on a square plate-like base 1. The two X-axis guides 2 extend in directions parallel to each other, and this direction is the X-axis direction. An X-axis table (intermediate table) 3 is provided on the X-axis guide 2. An X-axis copying portion (not shown) that follows the X-axis guide 2 is formed on the lower surface of the X-axis table 3, and the X-axis table 3 is movable in the X-axis direction. On the other hand, two Y-axis guides (second guide members) 4 extending in the Y-axis direction orthogonal to the X-axis direction are provided on the upper surface of the X-axis table 3. A movable table 5 is provided on the Y-axis guide 4. A Y-axis copying portion (not shown) that follows the Y-axis guide 4 is formed on the lower surface of the movable table 5, and the movable table 5 can move in the Y-axis direction, and the X-axis table 3 and the X-axis The guide 2 can also move in the X-axis direction. The upper surface of the movable table 5 is a flat surface, and a bonding head (working member) 10 is fixed thereto.

  An X-axis VCM (linear motor) 6 is disposed on the side of the movable table 5 in the X-axis direction. 3A and 3B are diagrams showing the structure of the X-axis VCM 6, wherein FIG. 3A is a plan view and FIG. 3B is a cross-sectional view taken along line AA in FIG.

  The X-axis VCM 6 is provided with a yoke portion 6c that is fixed to the base and has an opening on the movable table 5 side. An X-axis movable element 6a connected to the side surface of the movable table 5 and a coil 6b wound around the X-axis movable element 6a are inserted into the yoke portion 6c from the opening. The coil 6 b is wound in parallel with the surface of the movable table 5. The size of the opening is approximately equal to or greater than the movable range of the movable table 5 in the Y-axis direction, and the mover 6a and the coil 6b can move without being restricted in the Y-axis direction. A magnet 6d whose S pole faces downward and a magnet 6e whose N pole faces downward are attached to the upper surface inside the yoke portion 6c. Further, on the bottom surface inside the yoke portion 6c, a magnet 6f with the north pole facing upward and a magnet 6g with the south pole facing upward are mounted at positions facing the magnets 6d and 6e, respectively. In this way, a magnetic circuit for forming a magnetic field inside and around the coil 6b is formed on the X-axis VCM 6.

  In the X-axis VCM 6 configured in this way, when a magnetic field as shown by an arrow in FIG. 3B is formed and a current in the direction shown in FIG. 3B flows through the coil 6b, The mover 6a moves in the direction.

  A Y-axis VCM (linear motor) 7 is disposed on the side of the movable table 5 in the Y-axis direction. Similarly to the X-axis VCM 6, the Y-axis VCM 7 is provided with a yoke portion 7 c that is fixed to the base and has an opening on the movable table 5 side. A Y-axis movable element 7a connected to the side surface of the movable table 5 and a coil 7b wound around the Y-axis movable element 7a are inserted into the yoke portion 7c from the opening. The coil 7 b is wound in parallel with the surface of the movable table 5. The size of the opening is approximately equal to or greater than the movable range of the movable table 5 in the X-axis direction, and the mover 7a and the coil 7b can move without being restricted in the X-axis direction. Further, similarly to the X-axis VCM6, the Y-axis VCM7 is formed with a magnetic circuit that forms a magnetic field inside and around the coil 7b.

  The movable table 5 including the Y-axis copying unit, the X-axis moving element 6a, and the Y-axis moving element 7a constitute the stage upper stage 8, and the X-axis table 3 including the X-axis copying part and the Y-axis guide 4 include the middle stage of the stage. Part 9 is configured. The movable table 5 and the bonding head 10 constitute a movable part.

  Note that the mass of the bonding head 10 is larger than that of the upper step portion 8 and the middle step portion 9. For this reason, the overall center of gravity of the movable part composed of the bonding head 10, which is a member movable in the X-axis direction or the Y-axis direction, the upper step portion 8, and the middle step portion 9 is integrated with the bonding head 10 and the upper step portion 8. Is a single member, the position of the center of gravity of the member substantially coincides. Accordingly, when the bonding head 10 is moved in either the X-axis direction or the Y-axis direction, the position of the center of gravity is simultaneously moved in the same direction by substantially the same distance.

  Further, an X-axis direction position detector (not shown) for detecting the relative position of the movable part with respect to the base 1 in the X-axis direction is attached to the lower surface of the X-axis table 3. A Y-axis direction position detector (not shown) for detecting the relative position of the movable part with respect to the base 1 in the Y-axis direction is attached. A straight line that passes through the position where the X-axis direction position detector is attached and is parallel to the X-axis direction overlaps with a straight line that passes through the center of gravity of the movable part and is parallel to the X-axis direction in plan view, and A straight line passing through the position where the detector is attached and parallel to the Y-axis direction substantially overlaps with a straight line passing through the center of gravity of the movable part and parallel to the Y-axis direction in plan view. As the X-axis position detector and the Y-axis position detector, for example, a one-dimensional optical sensor and a magnetic sensor can be used. When using an optical sensor, for example, a scale indicating the amount of movement in the X-axis direction and the Y-axis direction is provided at the position of the surface of the base 1 facing this.

  Further, instead of the X-axis position detector and the Y-axis position detector, a position detector composed of a two-dimensional optical sensor capable of detecting the amount of movement in the plane can be used. In this case, the position detector is attached to the lower surface of the movable table 5, and a scale indicating the amount of movement in the X-axis direction and the Y-axis direction is provided on the surface of the base 1.

Next, the operation of the wire bonder stage of the reference example configured as described above will be described. 4A and 4B are diagrams showing a change in the position of the center of gravity G of the movable part when the bonding head 10 is moved in the Y-axis direction. FIG. 4A is a schematic diagram showing the position before the movement, and FIG. It is a schematic diagram which shows a back position.

  In order to move the movable table 5 in the Y-axis direction, the Y-axis VCM 7 is driven. Thereby, the movable table 5 is guided in the Y-axis direction with respect to the X-axis table 3 following the Y-axis guide 4. At this time, even if the position of the movable table 5 in the X-axis direction changes, the Y-axis movable element 7a can move without being constrained in the X-axis direction, and the integrated bonding head 10 can be moved. Since the total mass of the members including the upper stage 8 is heavier than that of the middle stage 9, the position of the center of gravity G of the movable part hardly changes. Therefore, the force from the Y-axis VCM 7 acts on the position of the center of gravity G of the movable part.

  On the other hand, when the movable table 5 is moved in the X-axis direction, the X-axis VCM 6 is driven. Thereby, the X-axis table 3 is guided in the X-axis direction with respect to the base 1 following the X-axis guide 2, and the movable table 5 provided thereon moves in the X-axis direction. At this time, even if the position of the upper stage portion 8 in the Y-axis direction changes, the X-axis movable element 6a directly connected to the movable table 5 can move without being restricted in the Y-axis direction. The position of the center of gravity G of the movable part hardly changes. Accordingly, the force from the X-axis VCM 6 acts on the position of the center of gravity G of the movable part.

Thus, according to the wire bonder stage of this reference example , the position of the center of gravity G hardly changes even when the movable table 5 moves in either the X-axis direction or the Y-axis direction. Therefore, almost no moment force is generated. Therefore, for example, even if the movable table 5 moves in the Y-axis direction, the yawing peak is small in terms of the transmission characteristics of the position with respect to the VCM driving force in the X-axis direction. It is only necessary to pay attention to the rigidity in the axial translation direction. Further, when driving in the Y-axis direction, it is not necessary to consider the rigidity that supports the moment load. In general, since the rigidity in the translation direction is larger than the rigidity in the yawing direction, in this embodiment, it is safe to use guides having lower rigidity than the conventional ones for the X-axis guide 2 and the Y-axis guide 4. It is. When a guide having low rigidity is used, the guide can be reduced in size, and a portion for holding the guide can also be reduced in size. As a result, since the total mass of the movable part is reduced, the movement can be speeded up.

Further, as an effect obtained by directly connecting the X-axis movable element 6a and the Y-axis movable element 7a to the side surface of the upper stage portion 8, vibration caused by the guide is suppressed. FIG. 5A is a schematic diagram showing a model in which the X-axis movable element is connected to the movable table as in the reference example of the present invention, and FIG. 5B is a conventional example in which the X-axis movable element is connected to the X-axis table. It is a schematic diagram which shows the model made.

  Equations of motion of the member 21 and the middle step 22 including the upper stage and the bonding head in the model shown in FIG. 5A are expressed by the following formulas 1 and 2, respectively.

  Where M is the total mass of the member 21, m is the mass of the middle step 22, K is the stiffness value of the Y-axis guide provided on the middle step 22, and k is the stiffness value of the X-axis guide provided on the base 23. , F is the driving force by the X-axis VCM.

  Further, the resonance frequency ω of this model is expressed by the following Equation 3.

  On the other hand, the equations of motion of the member 21 and the middle step 22 including the upper stage and the bonding head in the model shown in FIG. 5B are expressed by the following formulas 4 and 5, respectively.

  Similar to the model shown in FIG. 5A, the resonance frequency of this model is expressed by the following Equation 6.

  In any model, the stiffness value k is 0 because it is in the sliding direction.

  6A and 6B are diagrams showing frequency characteristics when the mass m of the middle stage portion 22 is equal to the total mass M of the member 21, wherein FIG. 6A is a graph showing the relationship between gain and frequency, and FIG. It is a graph which shows the relationship with a frequency. 7A and 7B are diagrams showing frequency characteristics when the mass m of the middle stage portion 22 is smaller than the total mass M of the member 21, wherein FIG. 7A is a graph showing the relationship between gain and frequency, and FIG. It is a graph which shows the relationship with a frequency. FIGS. 8A and 8B are graphs showing the closed loop characteristics with respect to FIGS. 6A and 6B, and FIGS. 9A and 9B are FIGS. 7A and 7B. It is a graph which shows the closed loop characteristic with respect to.

  From Equations 3 and 6, if the total mass of the movable part consisting of the member 21 consisting of the upper stage part and the bonding head and the middle stage part 22 is constant, the mass m of the middle stage part 22 is equal to the total mass M of the member 21. 6 (a) and 6 (b), the resonance frequency ω is the lowest. In general, the bonding head of the wire bonder is heavier than the upper stage and the middle stage, and the total mass of the member 21 is larger than that of the middle stage 22.

In the above-described reference example of the present invention, since both the X-axis movable element 6a and the Y-axis movable element 7a are directly connected to the upper stage 8, the middle stage 9 has a VCM movable element driven in one axial direction. If the total mass of the member made up of the upper stage portion 8 and the bonding head 10 compared with the mass of the middle stage portion becomes heavier than the case where they are connected, and if the mass of the entire movable portion is constant, FIG. As shown in a) and (b), the natural frequency (resonance frequency) increases. In addition, when feedback control is performed on the XY stage, the natural frequency, which is a problem in terms of control, becomes high. Compare FIGS. 8 (a) and 8 (b) with FIGS. 9 (a) and 9 (b). As can be seen, the control bandwidth is widened and controllability is improved.

According to this reference example , as described above, vibration in the yawing direction can be suppressed. Hereinafter, this effect will be described with reference to the drawings. 10A and 10B are diagrams showing frequency characteristics in a conventional wire bonder stage, where FIG. 10A is a graph showing the relationship between gain and frequency, and FIG. 10B is a graph showing the relationship between phase and frequency. 11A and 11B are diagrams showing frequency characteristics in the wire bonder stage according to the embodiment of the present invention, wherein FIG. 11A is a graph showing the relationship between gain and frequency, and FIG. 11B is a graph showing the relationship between phase and frequency. FIG. FIGS. 12A and 12B are graphs showing the closed loop characteristics with respect to FIGS. 10A and 10B, and FIGS. 13A and 13B are FIGS. 11A and 11B. It is a graph which shows the closed loop characteristic with respect to.

In the conventional wire bonder stage, the vibration in the yawing direction is generated because the center of gravity is not driven, and this vibration has been a problem in control. As shown in FIGS. 10A and 10B, the vibration in the yawing direction is generated at a frequency lower than that in the translational direction. On the other hand, in the reference example of the present invention, since the center of gravity of the movable part is driven, vibration in the yawing direction is suppressed as shown in FIGS. 11 (a) and 11 (b). In addition, since it is difficult to control the influence of the mechanical resonance peak, it is possible to obtain a stable wide control band as can be seen from a comparison between FIGS. 12 (a) and 12 (b) and FIGS. 13 (a) and 13 (b). Can do.

FIG. 14 is a schematic diagram for explaining the change in the detection amount depending on the position of the position detector of the one-dimensional sensor. In a coordinate system in which the center of gravity of the movable part is the origin O, when the position detector is provided at a position A rotated by θ ° from the X axis at a distance r from the center of gravity, the position detector further moves from the X axis to θ. _When the position detector is rotated by ₀ °, the detection amount when the position detector is the X-axis direction position detector and the detection amount when the position detector is the Y-axis direction position detector are expressed by the following equations 7 and 8, respectively.

  Therefore, in the range of 0 ≦ θ ≦ 180 °, the X-axis direction position detector is disposed at the position B of θ = 0 °, and the Y-axis direction position detector is disposed at the position C of θ = 90 °. The detection amount is the smallest. Therefore, when using a one-dimensional sensor, if any position detector in the direction of the drive axis is placed on the drive axis that passes through the center of gravity of the movable part, the mechanical resonance peak is less likely to be recognized by the control system. In addition, it is possible to expand the closed-loop control band when a feedback control unit that performs control based on the amount of movement is provided to configure control feedback, thereby improving controllability. On the other hand, when using a two-dimensional sensor, if the position detector is arranged at the center of gravity of the movable part, the controllability is similarly improved.

  Note that the structure of the VCM is not limited to that shown in FIGS. 3 (a) and 3 (b). 15A and 15B are diagrams showing the structure of another VCM. FIG. 15A is a plan view, and FIG. 15B is a cross-sectional view taken along line BB in FIG.

  The VCM is provided with a rectangular tube-shaped yoke portion 31 that is fixed to the base and has an opening that penetrates in the lateral direction. An iron core 32 that divides the opening into two spaces is provided at the intermediate height of the yoke portion 31. Further, the VCM is provided with a mover 33 connected to a movable table and a coil 34 wound around the mover 33. The coil 34 is wound so as to surround the iron core 32. The mover 33 is provided with a fixed portion 33a fixed to the movable table and a connecting portion 33b for connecting the fixed portion 33a and a portion around which the coil 34 is wound. The length of the coil 34 in the lateral direction is approximately the same as or longer than the movable range of the movable table, and the mover 33 and the coil 34 can move without being constrained in the direction orthogonal to the driving direction. A magnet 35 with the north pole facing downward is attached to the upper surface inside the yoke portion 31. Further, a magnet 36 with the south pole facing upward is attached to the bottom surface inside the yoke portion 31 at a position facing the magnet 35. Thus, a magnetic circuit for forming a magnetic field in and around the coil 34 is formed in the VCM.

  In the VCM configured as described above, when a magnetic field as shown by an arrow in FIG. 15B is formed and a current in the direction shown in FIG. The mover 33 moves.

  The linear motor is not limited to the VCM. For example, even if an AC linear motor is used, the effect of the present invention can be obtained.

Furthermore, in the above-described reference example , the movable table is mechanically guided using the guide member, but an air bearing may be used as long as the center of gravity of the movable portion is driven.

Next, a first embodiment of the present invention will be described. In the first embodiment, the X-axis VCM mover and the Y-axis VCM mover are not constrained by the movement of the movable table in the Y-axis direction and the X-axis direction, respectively. FIG. 16 is a schematic diagram showing the structure of the wire bonder stage according to the first embodiment of the present invention. In the first embodiment shown in FIG. 16, the same components as those in the reference example shown in FIG. 1 and the like are denoted by the same reference numerals, and detailed description thereof is omitted.

In the first embodiment, a plate-like cam follower guide (first protrusion guide member) 51 extending in the Y-axis direction is provided on the end of the movable table 5 in the X-axis direction. A plate-like cam follower guide (second protrusion guide member) 52 extending in the X-axis direction is provided on the end in the direction. In this embodiment, as shown in FIG. 16, the cam follower guides 51 and 52 are connected to each other, but may be separated.

  An X-axis VCM 56 is disposed on the side of the movable table 5 on the side where the cam follower guide 51 is provided, and a Y-axis VCM 57 is disposed on the side of the end on the side where the cam follower guide 52 is provided. Yes.

  The X-axis VCM 56 is provided with a rectangular cylindrical yoke portion 56c having an opening that is fixed to the base and penetrates in the lateral direction. An iron core 56d that partitions the opening into two spaces is provided at the intermediate height of the yoke portion 56c. Further, the X-axis VCM 56 is provided with an X-axis mover 56a extending up above the movable table 5 and a coil 56b wound around the X-axis mover 56a. The coil 56b is wound so as to surround the iron core 56d. The length in the vertical direction and the horizontal direction of the coil 56b is, for example, such that it does not contact the iron core 56d. Two cam followers (first protrusions) 56f and 56g extending in the vertical direction are fixed to the end of the X-axis movable element 56a. The two cam followers 56f and 56g are arranged so that the cam follower guide 51 is sandwiched between them. Magnets (not shown) are attached to the top and bottom surfaces inside the yoke portion 56c, and a magnetic circuit for forming a magnetic field is formed inside and around the coil 56b. That is, the X-axis VCM 56 has a structure as shown in FIG. Furthermore, a coil guide 56h fixed to the base on both sides of the yoke portion 56c is provided. Following the coil guide 56h, the X-axis movable element 56a moves in the X-axis direction.

  Similarly, the Y-axis VCM 57 is provided with a rectangular cylindrical yoke portion 57c having an opening that is fixed to the base and penetrates in the lateral direction. An iron core 57d that partitions the opening into two spaces is provided at the intermediate height of the yoke portion 57c. Further, the Y-axis VCM 57 is provided with a Y-axis mover 57a extending to the upper side of the movable table 5 and a coil 57b wound around the Y-axis mover 57a. The coil 57b is wound so as to surround the iron core 57d. In addition, the length of the longitudinal direction and the horizontal direction of the coil 57b is a thing of the grade which does not contact the iron core 57d, for example. Two cam followers 57 (second protrusions) f and 57g extending in the vertical direction are fixed to the end of the Y-axis movable element 57a. The two cam followers 57f and 57g are arranged so that the cam follower guide 52 is sandwiched between them. Magnets are attached to the top and bottom surfaces inside the yoke portion 57c, and a magnetic circuit for forming a magnetic field is formed inside and around the coil 57b. That is, the Y-axis VCM 57 has a structure as shown in FIG. Furthermore, a coil guide 57h fixed to the base on both sides of the yoke portion 57c is provided. The Y-axis movable element 57a moves in the Y-axis direction following the coil guide 57h.

As described above, in the first embodiment, the X-axis movable element 56a and the Y-axis movable element 57a are connected to the movable table 5 via the cam follower and the cam follower guide.

Next, the operation of the wire bonder stage of the first embodiment configured as described above will be described.

  When the movable table 5 is moved in the X-axis direction, the X-axis VCM 56 is driven. As a result, the driving force is transmitted from the cam follower 56f or 56g to the cam follower guide 51 fixed to the movable table 5, so that the X-axis table 3 is guided in the X-axis direction with respect to the base 1 along the X-axis guide 2. The movable table 5 provided thereon moves in the X-axis direction. At this time, the cam follower guide 52 also moves in the X-axis direction, but the cam follower guide 52 only moves between the cam followers 57f and 57g and does not restrain them, so the Y-axis movable element 57a remains stopped. That is, the movable table 5 moves independently of the Y-axis VCM 57.

  On the other hand, when the movable table 5 is moved in the Y-axis direction, the Y-axis VCM 57 is driven. As a result, the driving force is transmitted from the cam follower 57f or 57g to the cam follower guide 52 fixed to the movable table 5, so that the movable table 5 is guided in the Y axis direction with respect to the X axis table 3 following the Y axis guide 4. Is done. At this time, the cam follower guide 51 also moves in the Y-axis direction, but the cam follower guide 51 only moves between the cam followers 56f and 56g and does not restrain them, so the X-axis movable element 56a remains stopped. That is, the movable table 5 moves independently of the X axis VCM 56.

As described above, according to the first embodiment, the X-axis movable element 56a of the X-axis VCM 56 and the Y-axis movable element 57a of the Y-axis VCM 57 are connected to the movable table 5 via the cam follower and the cam follower guide. The movable part and the movable element of the VCM of both axes can move independently. For this reason, it is not necessary to provide the Y-axis movable element 57a with redundancy that allows the Y-axis movable element 57a to move widely in the X-axis direction, and the Y-axis VCM 57 can be downsized. Further, since the Y-axis movable element 57a is not fixed to the movable table 5, when a thrust in the X-axis direction similar to the conventional case is applied to the movable table 5, a smaller X-axis VCM 56 than the conventional one should be used. Can do. For this reason, since the inertia of a movable part becomes small and a natural frequency becomes high, a vibration can be suppressed. Further, since the movable elements of the VCMs on both axes are not fixed to the movable part, the mass acting on the X-axis guide 2 and the Y-axis guide 4 is reduced. As a result, the X-axis guide 2 and the Y-axis guide 4 can use guides having lower rigidity than the conventional one, and the wire bonder stage itself can be reduced in weight.

Furthermore, in the first embodiment, since the X-axis movable element 56a and the Y-axis movable element 57a are connected to the upper stage, the natural frequencies of the X-axis guide 2 and the Y-axis guide 4 are increased, and the control is performed. Improves. That is, as described above, the vibration frequency caused by the guide is the lowest when the mass of the middle stage and the upper stage is equal if the total mass of the movable part composed of the middle stage and the upper stage is constant. The XY stage is the most disadvantageous configuration. However, in the case of a wire bonder, since the bonding head is generally significantly heavier than other members, the total mass of the bonding head and the upper stage is larger than the mass of the middle stage, and the vibration frequency is larger. In particular, when both the X-axis movable element 56a and the Y-axis movable element 57a are connected to the upper stage as in the present embodiment, the middle stage becomes even lighter than the upper stage and the natural frequency increases. Therefore, the controllability is remarkably improved.

Next, another reference example of the present invention will be described. In another reference example , the connection method between each VCM and the movable table is different from that in the first embodiment. FIG. 17 is a schematic view showing the structure of a wire bonder stage according to another reference example of the present invention.

In another reference example , two cam followers 56 i and 56 j are formed on the end of the movable table 5 in the X-axis direction. The two cam followers 56i and 56j are arranged side by side in the X-axis direction. Two cam followers 57 i and 57 j are formed on the end of the movable table 5 in the Y-axis direction. The two cam followers 57i and 57j are arranged side by side in the Y-axis direction.

On the other hand, no cam follower is provided at the end of the X-axis movable element 56a, and a plate-like cam follower guide 53 protruding downward from the end is provided. The end face of the cam follower guide 53 abuts against the movable table 5 between the cam followers 56i and 56j.

  Similarly, no cam follower is provided at the end of the Y-axis movable element 57a, and a plate-like cam follower guide 54 protruding downward from the end is provided. The end surface of the cam follower guide 54 contacts the movable table 5 between the cam followers 57i and 57j.

In another reference example thus configured, members the cam follower and the cam follower guide is fixed, since only are interchanged in the first embodiment, the same by the same operation as in the first embodiment An effect is obtained.

Next, second and third embodiments of the present invention will be described. In the second and third embodiments, each mover and the movable table are connected via a linear guide composed of a slider and a rail.

FIG. 18 is a schematic view showing the structure of a wire bonder stage according to the second embodiment of the present invention, and FIG. 19 is a schematic view showing the structure of a wire bonder stage according to the third embodiment of the present invention.

In the second embodiment, a rail 61a is attached to one side surface of the movable table 5 in the X-axis direction, and a rail 62a is attached to one side surface in the Y-axis direction. A slider 61b that slides along the rail 61a is attached to the end surface of the X-axis movable element 56a, and a slider 62b that slides along the rail 62a is attached to the end face of the Y-axis movable element 57a. One linear guide is constituted by the rail 61a and the slider 61b, and one linear guide is constituted by the rail 62a and the slider 62b. In the present embodiment, since the linear guide is provided, the coil guides 56h and 57h are unnecessary.

Also in the second embodiment configured as described above, when the movable table 5 moves in the X-axis direction, the Y-axis movable element 57a remains stopped, and the movable table 5 moves in the Y-axis direction. The X-axis movable element 56a remains stopped. Therefore, the same effect as the first embodiment can be obtained.

In the third embodiment, sliders 61b and 62b are attached to the side surface of the movable table 5, and rails 61a and 62a are attached to the end surfaces of the X-axis movable element 56a and the Y-axis movable element 57a, respectively. Also in the present embodiment, since the linear guide is provided, the coil guides 56h and 57h are unnecessary.

In the third embodiment thus configured, members the slider and the rail is attached, since only are interchanged with the second embodiment, the same operation as the second embodiment, the The same effect as in the first embodiment can be obtained.

In addition to the linear guide, a linear motion guide device such as a cross roller may be used. Further, in the first to third embodiments, the VCM as shown in FIG. 15 is used, but the VCM as shown in FIG. 3 similar to the reference example can also be used. Further, like the reference example , the linear motor is not limited to the VCM. For example, even if an AC linear motor is used, the effect of the present invention can be obtained.

It is a schematic diagram which shows the structure of the wire bonder stage which concerns on the reference example of this invention. It is a schematic diagram which shows the state by which the bonding head was attached on the wire bonder stage shown in FIG. It is a figure which shows the structure of X-axis VCM6, Comprising: (a) is a top view, (b) is sectional drawing by the AA of (a). It is a figure which shows the change of the position of the gravity center G of a movable part when the bonding head 10 is moved to a Y-axis direction, Comprising: (a) is a schematic diagram which shows the position before a movement, (b) is the position after a movement It is a schematic diagram which shows. (A) is a schematic diagram showing a model in which an X-axis mover is connected to an X-axis table as in the prior art, and (b) is an X-axis mover connected to the movable table as in the reference example of the present invention. It is a schematic diagram which shows a model. It is a figure which shows the frequency characteristic when the mass m of the middle step part 22 is equal to the total mass M of the member 21, Comprising: (a) is a graph figure which shows the relationship between a gain and a frequency, (b) is a phase and a frequency. It is a graph which shows a relationship. It is a figure which shows the frequency characteristic when the mass m of the middle step part 22 is smaller than the total mass M of the member 21, Comprising: (a) is a graph figure which shows the relationship between a gain and a frequency, (b) is a phase and a frequency. It is a graph which shows a relationship. (A) And (b) is a graph which shows the closed loop characteristic with respect to FIG. 6 (a) and (b). (A) And (b) is a graph which shows the closed loop characteristic with respect to Fig.7 (a) and (b). It is a figure which shows the frequency characteristic in the conventional wire bonder stage, Comprising: (a) is a graph figure which shows the relationship between a gain and a frequency, (b) is a graph figure which shows the relationship between a phase and a frequency. It is a figure which shows the frequency characteristic in the wire bonder stage which concerns on the reference example of this invention, Comprising: (a) is a graph which shows the relationship between a gain and a frequency, (b) is a graph which shows the relationship between a phase and a frequency. . (A) And (b) is a graph which shows the closed loop characteristic with respect to Fig.10 (a) and (b). (A) And (b) is a graph which shows the closed loop characteristic with respect to Fig.11 (a) and (b). It is a schematic diagram for demonstrating the change of the detection amount by the position of the position detector of a one-dimensional sensor. It is a figure which shows the structure of other VCM, Comprising: (a) is a top view, (b) is sectional drawing by the BB line of (a). It is a schematic diagram which shows the structure of the wire bonder stage which concerns on 1st Example of this invention. It is a schematic diagram which shows the structure of the wire bonder stage which concerns on the other reference example of this invention. It is a schematic diagram which shows the structure of the wire bonder stage which concerns on the 2nd Example of this invention. It is a schematic diagram which shows the structure of the wire bonder stage which concerns on the 3rd Example of this invention. It is a schematic diagram which shows the structure of the conventional wire bonder stage. It is a schematic diagram which shows the state by which the bonding head was attached on the conventional wire bonder stage shown in FIG. It is a figure which shows the change of the position of the gravity center g of a movable part when the bonding head 110 is moved to the Y-axis direction, Comprising: (a) is a schematic diagram which shows the position before a movement, (b) is the position after a movement It is a schematic diagram which shows.

Explanation of symbols

1, 101; base 2, 102; X-axis guide 3, 103; X-axis table 4, 104; Y-axis guide 5, 105; movable table 6, 56, 106; X-axis VCM
6a, 56a, 106a; X-axis mover 6b, 56b, 106b; X-axis coil 6c, 56c, 106c; Yoke part 6d, 6e, 6f, 6g; Magnet 7, 57, 107; Y-axis VCM
7a, 57a, 107a; Y-axis mover 7b, 57b, 107b; Y-axis coil 7c, 107c; Magnetic circuit 8, 108; Upper stage part 9, 109; Middle stage part 10, 110; Bonding head 21; 23; base 31; yoke part 32, 106d; iron core 33; mover 33a; fixed part 33b; coupling part 34; coil 35, 36; magnet 51, 52; cam follower guide 56f, 56g, 57f, 57g; 57h; coil guide 61a, 62a; rail 61b, 62b; slider G, g; center of gravity

Claims (12)

A base, a movable table arranged on the base so as to be movable in the X direction and the Y direction in an XY plane, a work member provided on the movable table, and a magnetic field fixed to a base, respectively. A center of gravity of a movable part comprising the stator, a movable member that is movable relative to the stator, and a coil that is wound around the stator and that is affected by a magnetic field generated by the stator, and that includes the movable table and the working member. First and second linear motors that apply driving forces in the X direction and Y direction to the movable table at the same height as the position, respectively, and a movable element of the first linear motor independent of the movable table The first connecting means for connecting to the movable table while being movable in the Y direction, and the movable element of the second linear motor can be moved in the X direction independently of the movable table. And a second coupling means coupled to the movable table in the state, and the first coupling means is a plate-shaped first cam follower guide disposed on the upper surface of the movable table so as to extend in the Y direction. And a pair of first cam followers protruding downward from the end of the mover of the first linear motor and sandwiching the first cam follower guide, wherein the second connecting means comprises the movable table A pair of plate-like second cam follower guides arranged so as to extend in the X direction on the upper surface of the first linear motor, and a pair of the second linear motors that protrude downward from the end of the mover of the second linear motor and sandwich the second cam follower guide An XY stage comprising the second cam follower. A base, a movable table arranged on the base so as to be movable in the X direction and the Y direction in an XY plane, a work member provided on the movable table, and a magnetic field fixed to a base, respectively. A center of gravity of a movable part comprising the stator, a movable member that is movable relative to the stator, and a coil that is wound around the stator and that is affected by a magnetic field generated by the stator, and that includes the movable table and the working member. First and second linear motors that apply driving forces in the X direction and Y direction to the movable table at the same height as the position, respectively, and a movable element of the first linear motor independent of the movable table The first connecting means for connecting to the movable table while being movable in the Y direction, and the movable element of the second linear motor can be moved in the X direction independently of the movable table. Second connecting means for connecting to the movable table in the state, and the first connecting means is provided on the side surface of one end portion of the movable table in the X direction so as to extend in the Y direction. A rail and a first slider that is provided on an end surface of the movable element of the first linear motor and slides along the first rail, and the second coupling means is in the Y direction of the movable table. A second rail provided on the side surface of one end of the second linear motor so as to extend in the X direction; a second slider provided on an end surface of the movable element of the second linear motor and sliding along the second rail; An XY stage characterized by comprising: A base, a movable table arranged on the base so as to be movable in the X direction and the Y direction in an XY plane, a work member provided on the movable table, and a magnetic field fixed to a base, respectively. A center of gravity of a movable part comprising the stator, a movable member that is movable relative to the stator, and a coil that is wound around the stator and that is affected by a magnetic field generated by the stator, and that includes the movable table and the working member. First and second linear motors that apply driving forces in the X direction and Y direction to the movable table at the same height as the position, respectively, and a movable element of the first linear motor independent of the movable table The first connecting means for connecting to the movable table while being movable in the Y direction, and the movable element of the second linear motor can be moved in the X direction independently of the movable table. Second connecting means for connecting to the movable table in the state, and the first connecting means is provided on the end face of the mover of the first linear motor so as to extend in the Y direction. A rail, and a first slider that is provided on a side surface of one end portion in the X direction of the movable table and slides along the first rail, and the second connecting means includes the second linear motor. A second rail provided on the end surface of the movable element so as to extend in the X direction, and a second slider provided on a side surface of one end portion in the Y direction of the movable table and sliding along the second rail. An XY stage characterized by comprising: The XY stage according to any one of claims 1 to 3, wherein the working member is a bonding head and is used for wire bonding. A first position detector arranged on a straight line passing through the center of gravity in plan view and extending in the X direction; and detecting the amount of movement of the movable part in the X direction; and extending in the Y direction through the center of gravity in plan view. 5. The XY stage according to claim 1, further comprising: a second position detector that is arranged on a straight line and detects a movement amount of the movable portion in the Y direction. 5. The XY according to claim 1, further comprising a position detector that is disposed at the position of the center of gravity in plan view and detects a movement amount of the movable part in the X direction and the Y direction. stage. The XY stage according to claim 5 or 6, wherein the position detector includes an optical sensor. The XY stage according to claim 7, wherein a scale indicating movement amounts in the X direction and the Y direction is provided on the base surface. The XY stage according to claim 1, wherein the linear motor has a magnetic circuit that forms a magnetic field in a vertical direction in the stator. The XY stage according to claim 9, wherein the magnetic circuit includes at least two magnets arranged so that poles different from each other in the vertical direction face each other. 11. The XY stage according to claim 1, further comprising a feedback control unit configured to control an operation of the linear motor based on a movement amount detected by the position detector. The XY stage according to any one of claims 1 to 9, wherein the linear motor is an AC linear motor.

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