KR20040086183A - Fine-control stage apparatus - Google Patents

Abstract

PURPOSE: A stato-stage apparatus is provided to realize a high standstill-stability and a high responsiveness in spite of a load of 5 kg or more. CONSTITUTION: A stato-stage apparatus includes a base(100), a tilt stage, and an X-Y stage. The tilt stage includes a tilt plate(201) and at least three converting mechanisms. Each converting mechanism is composed of a first piezo-actuator(Z2-2) and an edge stage(215). The converting mechanism is used for converting a horizontal-direction motion into a vertical-direction motion. The X-Y stage includes an X-Y plate, second piezo-actuators, and a third piezo-actuator. The second piezo-actuators are used for driving the X-Y plate at a plurality of points from one side. The third piezo-actuator is used for driving the X-Y plate from the other side.

Description

Fine-control stage apparatus

The present invention relates to a fine motion stage apparatus using a piezo actuator as a drive source.

Various types of stage devices are used in the semiconductor device manufacturing field. For example, in the wafer mounting stage apparatus employed in the electron beam exposure apparatus, a coarse motion stage device which operates at the time of conveyance of wafers and movement between chips, and a fine motion stage which performs positioning of several nm to about 10 nm. Many configurations in which the devices are combined are employed. This type of stage apparatus is used to move the mounted wafer in the X-axis direction and the Y-axis direction which are perpendicular to each other on the horizontal plane. This type of stage apparatus is also required to be operable under high vacuum (10 ^-4 Pa) and to have non-magnetic properties.

In the fine motion stage apparatus, many actuators (piezo actuators) using an elastic hinge and a piezoelectric element are employed (see Patent Document 1, for example).

The fine motion stage device is required to have a high stop stability and a response to realize a movement amount of 1 m to several m to several 10 msec to 100 msec in order to realize high throughput.

By the way, the load mass mounted in the micro-movement stage apparatus in this kind of stage apparatus has become about 15-25 kg by the wafer, the wafer chuck, the laser interferometer mirror, etc. However, most of the loading loads of the fine motion stage apparatus so far are about 5 kg. When a load of about 15 to 25 kg is mounted on a microscopic stage device having a loading load of 5 kg, the resonance frequency is lowered, and the stopping stability and responsiveness are greatly reduced.

For example, when a load of about 15 to 25 kg is loaded on a microscopic stage device having a payload of 5 kg, the natural frequency (resonant frequency) in the X-axis direction and the Y-axis direction is about 30 Hz, and the stopping stability is 15 to 30 nm. You can only secure enough. In addition, for a step response of about several micrometers, a time of about several hundred msec is required before the correction.

(Patent Document 1)

Japanese Patent Laid-Open No. 11-271479

Then, the subject of this invention is providing the fine motion stage apparatus which can implement | achieve a high stop stability and high responsiveness even when a mounting load exceeds 5 kg.

Another object of the present invention is to enable the fine motion stage apparatus to have multiple degrees of freedom of three or more degrees of freedom.

Another object of the present invention is to provide a fine moving stage apparatus capable of improving vibration damping performance.

1 is a front view of a fine moving stage apparatus according to the first embodiment of the present invention.

FIG. 2 is a plan view of the fine motion stage device of FIG. 1 seen from the height position of line B of FIG. 1.

FIG. 3 is a side view of the fine motion stage device of FIG. 1 seen from the right side of FIG. 1.

FIG. 4 is a plan view of the fine motion stage apparatus of FIG. 1 seen from the height position of line A of FIG. 1.

FIG. 5 is a front sectional view of the fine motion stage device of FIG. 1 taken along line I of FIG. 4.

FIG. 6: is a schematic diagram for demonstrating the structure of the drive mechanism of the tilt stage in the fine motion stage apparatus of FIG.

It is a schematic diagram for demonstrating the installation form of the tilt plate to the drive mechanism of the tilt stage shown in FIG.

FIG. 8: is a schematic diagram which shows the form of the combination of the tilt plate and X-Y plate shown in FIG.

Fig. 9 is a perspective view showing the configuration of main parts of the fine motion stage apparatus according to the second embodiment of the present invention.

FIG. 10 is a perspective view showing a configuration example of a main part of the Z-axis drive mechanism in the fine motion stage device of FIG. 9.

FIG. 11 is a perspective view showing a tilt plate with the components of the Z-axis drive mechanism further added to the configuration of FIG. 10. FIG.

FIG. 12 is a partial perspective view for explaining the attenuation action in the Z-axis direction in the fine motion stage apparatus of FIG. 9.

FIG. 13 is a plan view of the fine motion stage apparatus of FIG. 9. FIG.

FIG. 14 is a partially enlarged perspective view for explaining the attenuation structure in the X-axis direction and the Y-axis direction in the fine motion stage apparatus of FIG. 9.

It is a top view for demonstrating the guide system of the X-Y stage in the fine motion stage apparatus of FIG.

FIG. 16 is a cross-sectional view for explaining a structural example of a damper used as a damper in the fine motion stage apparatus of FIG. 9.

FIG. 17 is a side cross-sectional view for explaining the fine motion stage device of FIG. 9 centering on a Z3-axis actuator which is a component of a Z-axis drive mechanism. FIG.

Fig. 18 shows piezo actuators for Z1-axis Z3-axis and its related elements, three main link hinges and two secondary link hinges, four dampers for Z-axis damping, and X- and Y-axis damping. The arrangement relationship of the four dampers etc. of a dragon is shown by the top view.

19 is a side sectional view of a support structure of four dampers for X-axis damping and Y-axis damping.

Explanation of symbols on the main parts of the drawings

100: base plate

110, 120, 130, 203, 213, 223: piezo actuator

115, 125, 135, 205, 215, 225: wedge stage

201: tilt plate

202: Top Table

204, 214, 224: two stages

207, 217, 227: Z1 sensor, Z2 sensor, Z3 sensor

219, 229, 239, 249, 261-264: Damper

226: tilt hinge

228, 238: leaf spring

260: Damper Holder

270 damper ring

301: X-Y plate

302 X1 Piezo Actuator

303: X2 Piezo Actuator

304: Y Piezo Actuator

321, 322, 323: master link hinge

324, 325: secondary link hinge

According to the first aspect of the present invention, there is provided a tilting stage device comprising a tilt stage and an XY stage built on a base, wherein the tilt stage has a tilt plate and a combination of a first piezo actuator and a wedge stage. At least three transducers for converting a motion parallel to the base body into a motion in a Z-axis direction perpendicular to the base body are provided between the tilt plate and the base body, and the XY switch is the tilt plate. At least two second piezo actuators having an XY plate combined with each other and extending in parallel to one of the X and Y axis directions to drive the XY plate to at least two points, and an X and Y axis directions A fine piezo actuator having a third piezo actuator extending in the other direction to drive the XY plate Kinds of apparatus.

In the fine motion stage apparatus by a 1st aspect, the said tilt plate is arrange | positioned at equal angle intervals on the same circumference, and the said tilt plate is a Z-axis direction, (theta) x-axis direction about X-axis, and Y Displaceable in the θy-axis direction around the axis, the XY plate becomes displaceable together with the tilt plate, and in the θz-axis direction around the X-axis direction, Y-axis direction, and Z-axis independently of the tilt plate. Displacement is enabled.

In the fine motion stage apparatus by a 1st aspect, further, between the said tilt plate and the said XY plate, it guides the movement in the XY plane of this XY plate, and is high rigidity in the direction perpendicular | vertical to the said base body. Link hinges for providing the are provided in plural places.

In the fine motion stage apparatus by a 1st aspect, the leaf | plate spring for restraining the movement in the X-Y plane of this tilt plate is further provided between the said tilt plate and the said base body.

In the fine motion stage apparatus by a 1st aspect, the tilt hinge is interposed between the upper part of the movement part of the Z-axis direction in the said converter mechanism, and the said tilt plate.

In the microscopic stage apparatus according to the first aspect, the first piezo actuator may be a combination of two piezo actuator elements extending in parallel to each other such that their strokes are added by two stages.

According to the second aspect of the present invention, a top table for mounting a mounted object is further mounted on the XY plate, and has a damping effect in the Z-axis direction between the base body and the top table. A fine moving stage apparatus is provided, comprising a plurality of Z-axis attenuators.

In the microscopic stage apparatus according to the second aspect, at least three attenuators having a damping action in the X-axis direction and the Y-axis direction are disposed between the base body and the X-Y plate in the same X-Y plane.

In the fine motion stage apparatus by a 2nd aspect, the said tilt plate has a 1st opening in a center part, The said XY plate which has a smaller 2nd opening in this 1st opening is combined, A lower surface of the corresponding top table is provided with a damper ring of a size corresponding to the second opening, and the damper ring is slightly smaller than the inner diameter of the damper ring through a stand provided in the base body. A damper holder is provided, and between the damper holder and the damper ring, at least two X-axis attenuators having a damping action in the X-axis direction are provided to act in opposite directions on the coaxial axis, and at the same time, a damping action in the Y-axis direction. At least two Y-axis attenuators having a structure are installed to act in opposite directions on the coaxial axis.

In the fine motion stage apparatus according to the second aspect, the X-axis damper, Y-axis damper, and Z-axis damper each contain a vacuum grease base oil as damper oil for damping. And a damper made of a non-magnetic material including a return spring and a piston rod, wherein the X-axis damper and the Y-axis damper are respectively disposed such that the tip of the piston rod contacts the damper ring. The Z-axis damper is disposed so that the tip of the piston rod is in contact with the bottom surface of the top plate.

(Example)

With reference to FIGS. 1-8, 1st Embodiment of the fine motion stage apparatus by this invention is demonstrated. Although the fine motion stage apparatus which concerns on this embodiment may be used independently, it is usually combined with the X-Y stage apparatus which is a coarse motion stage apparatus. The X-Y stage apparatus includes an X table movable in the X-axis direction and a Y table movable in the Y-axis direction, for example, so that the X table moves on the Y table. Of course, the Y table may be configured to operate on the X table. This fine motion stage apparatus is mounted on the X table or the Y table in the X-Y stage apparatus.

The microscopic stage device is referred to as an XY stage, hereinafter referred to as an XY stage, although the Z-θx-θy axis stage (hereinafter referred to as a tilt stage) built on the base plate 100 is referred to as an XY stage. Different from the device).

First, the tilt stage will be described. As shown in FIG. 1, FIG. 2, the tilt stage has the tilt plate 201. FIG. As shown in FIG. 4, the tilt plates 201 are two sets of six piezo actuators (piezo actuator elements) (Z1-1, Z1-2) arranged in total so as to extend parallel to each other on the base plate 100. , Z2-1, Z2-2, Z3-1, Z3-2 and the wedge stage described later are driven in the vertical direction (Z-axis direction or vertical direction) with respect to the base plate 100. Hereinafter, the combination of the piezo actuators Z1-1 and Z1-2 is the Z1 axis and the combination of the piezo actuators Z2-1 and Z2-2 is the Z2 axis and the combination of the piezo actuators Z3-1 and Z3-2. Is called the Z3 axis.

With reference to FIG. 5 and FIG. 6 and FIG. 7 which are schematic diagrams, the structure and operation | movement detail about Z3 axis are demonstrated. The piezo fixing block 223 is provided in the base plate 100. One end of the piezo actuator Z3-2 is fixed to the piezo fixed block 223 and is connected to the piezo actuator Z3-1 through two stages 224. As a result, the drive stroke of the piezo actuator Z3-2 and the drive stroke of the piezo actuator Z3-1 are added to drive the wedge stage 225 with the added drive stroke.

The wedge stage is for converting the motion in the horizontal direction into the motion in the vertical direction, as is well known. In the present embodiment, the wedge stage 225 is provided with a 45 degree orthogonal converter, so that the horizontal displacement input by the two piezo actuators Z3-1 and Z2-2 and the vertical displacement output of the wedge stage 225 are It is comprised so that it may be one to one. The orthogonal converter comprises a combination of an inclined block 225-1 having an inclined surface of 45 degrees on the upper surface side and an inclined block 225-2 having an inclined surface of 45 degrees on the lower surface side. The inclined block 225-1 has a guide part for guiding the inclined block 225-2. The inclined block 225-2 can slide along the inclined surface of the inclined block 225-1 with the inclined surface guided by the guide part. As a result, when the inclined block 225-1 is displaced in the horizontal direction, the inclined block 225-2 is slid accordingly and displaced in the vertical direction.

By the wedge stage 225, the tilt hinge 226 fixed to the vertical motion part is driven to Z-axis direction. Then, the tilt plate 201 fixed to the tip of the tilt hinge 226 is driven in the Z-axis direction. In addition, the tilt plate 201 has an opening 201a (see FIG. 7) in the center. An X-Y plate 301 (see FIG. 2) is combined in the opening 201a. The top table 202 (see FIG. 5) is fixed to the X-Y plate 301. The X-Y plate 301 and the top table 202 will be described later.

Z1 axis and Z2 axis have the same configuration as Z3 axis. That is, the Z1 axis has a piezo fixed block 203, a double stage 204, and a wedge stage 205, and the Z2 axis has a piezo fixed block 213, a double stage 214, and a wedge stage 215. Has In particular, the wedge stage 205 of the Z1-axis, the wedge stage 215 of the Z2-axis, and the wedge stage 225 of the Z3-axis are arranged on the same circumference (indicated by a dashed-dotted line in FIG. 4), respectively. In particular, in the present embodiment, the wedge stages 205, 215, and 225 are arranged at positions corresponding to the vertices of the equilateral triangle, that is, at an angle interval of 120 degrees. These three axes of vertical movement are displaceable in the same direction. As a result, the tilt plate 201 performs the translational movement in the Z-axis direction, and the differential plate, i.e., the difference in the displacement amount of each axis, causes the tilt plate 201 to be in the θx-axis direction and the θy-axis direction. Rotation of Here, it goes without saying that the rotational motion in the θx-axis direction means the rotational motion around the X axis, and the rotational motion in the θy-axis direction means the rotational motion around the Y axis. In addition, the rotational motion in the θz-axis direction described later means a rotational motion around the Z-axis.

The position in the Z-axis direction is measured by the capacitive sensor here. The capacitive sensor is disposed between the base table 100 and the top table 202 which is the last movable part above the tilt plate 201. Hereinafter, the capacitive sensor for the Z1 axis is referred to as the Z1 sensor 207, the capacitive sensor for the Z2 axis is referred to as the Z2 sensor 217, and the capacitive sensor for the Z3 axis is referred to as the Z3 sensor 227. Each sensor 207, 217, 227 is provided at a position adjacent to the wedge stages 205, 215, 225, respectively. The measuring principle of the capacitive sensor is well known, but in brief, the microdisplacement in the Z-axis direction can be detected as a change in capacitance.

In this embodiment, the height of the top table 202 which is the last movable part is measured by these Z1 sensor 207, Z2 sensor 217, and Z3 sensor 227, and position control of the top table 202 is based on a measurement result. (Full closed control) is performed.

Usually, in the tilt stage, the height position of the tilt plate 201 from the base plate 100 is measured, and position control (semi-closed control) is performed based on the measurement result. However, this method cannot measure the positional error in the Z-axis direction when the X-Y stage is moved. This means that the positions of the Z-axis direction, the θx-axis direction, and the θy-axis direction of the top table 202 cannot be controlled. However, the arrangement of the Z-axis position measuring instrument according to this embodiment enables position control in the Z-axis direction, the θx-axis direction, and the θy-axis direction of the top table 202.

The guide system of the tilt stage includes a tilt hinge 206, 216, 226 mounted on each wedge stage 205, 215, 225, and a Z-axis direction mounted between the base plate 100 and the tilt plate 201. It is constituted by leaf springs 208, 218, 228 (see FIGS. 4, 7) which are only displaceable. These leaf springs 208, 218, and 228 constitute a highly rigid guide system that constrains the motion in the X-Y plane of the tilt plate 201, which is impossible to realize only by the guide portion of the wedge stage. In addition, the leaf springs 208, 218, and 228 are provided through the spring mounting parts 208-1, 218-1, and 228-1 provided in the base plate 100, respectively.

Next, with reference to FIGS. 1-3 and FIG. 8 which is a schematic diagram, an X-Y stage is demonstrated. The top table 202 is fixed to the X-Y plate 301. The X-Y plate 301 is assembled to the opening 201a of the center portion of the tilt plate 201. The XY plate 301 can be displaced in the Z-axis direction, the θx-axis direction, and the θy-axis direction together with the tilt plate 201, but is independent of the tilt plate 201 in the X-axis direction, the Y-axis direction, and the θz-axis direction. Displacement is enabled. That is, the X-Y plate 301 is driven by two X1 piezo actuators 302 and X2 piezo actuators 303 which extend in parallel to each other in the X axis direction with respect to the X axis direction. The X1 piezo actuator 302 and the X2 piezo actuator 303 are provided at regular intervals, and one end is fixed to the tilt plate 201, and the other end is connected to the X-Y plate 301. On the other hand, the X-Y plate 301 is driven by one Y piezo actuator 304 extending in the Y-axis direction with respect to the Y-axis direction. The Y piezo actuator 304 also has one end fixed to the tilt plate 201 and the other end connected to the X-Y plate 301.

The guide system of the X-Y stage is as follows. In the guide system in the XY plane, the X1 hinge 312 fixed to one end of the X1 piezo actuator 302 is fixed to the tilt plate 201 and the X1 hinge 311 fixed to the other end of the X1 piezo actuator 302. Is connected to the XY plate 301. Similarly, the X2 hinge 314 fixed to one end of the X2 piezo actuator 303 is fixed to the tilt plate 201, and the X2 hinge 313 fixed to the other end of the X2 piezo actuator 303 is the XY plate 301. Is connected to. Meanwhile, the Y hinge 316 fixed to one end of the Y piezo actuator 304 is fixed to the tilt plate 201, and the Y hinge 315 fixed to the other end of the Y piezo actuator 304 is the XY plate 301. Is connected to.

The guide system in the Z-axis direction includes three main link hinges 321, 322, and 323 and two secondary link hinges 324 and 325 provided between the XY plate 301 and the tilt plate 201. Is realized. 5, one of these link hinges, for example, the main link hinge 321, will be described. The link hinge block 321-1 is provided on the tilt plate 201 to vertically extend downward. The link hinge block 321-1 is provided with a hinge 321-2 extending upward therefrom and connected to the X-Y plate 301. The hinge 321-2 has a known spherical joint coupling and supports the X-Y plate 301 so as to be displaced in the X-Y plane, but to provide high rigidity in the Z-axis direction. The primary link hinges 322 and 323 and the secondary link hinges 324 and 325 have exactly the same structure. 8 shows a main link hinge 322 consisting of a link hinge block 322-1 and a hinge 322-2.

Three primary link hinges 321, 322, 323 are installed at positions corresponding to the vertices of a triangle, here an isosceles triangle, and two secondary link hinges 324, 325 are installed on both sides of the primary link hinge 321. It is. The main link hinges 321 to 323 and the sub link hinges 324 and 325 have a function of enabling displacement in the XY plane of the XY plate 301 and have great rigidity in the Z-axis direction. . Thereby, rigidity improves significantly compared with the conventional fine motion stage apparatus.

The operation of the X-Y stage will be described. When the X1 piezo actuator 302 and the X2 piezo actuator 303 operate in the same direction, the X-Y plate 301 performs translational movement in the X-axis direction. When the X1 piezo actuator 302 and the X2 piezo actuator 303 are differentially operated, i.e., have a difference in the displacement amount, the X-Y plate 301 operates in the? Z-axis direction. On the other hand, when the Y piezo actuator 304 is operated, the X-Y plate 301 translates in the Y axis direction.

The position of the XY plate 301 in the X-axis direction is determined by two capacitive sensors 326 and 327 (hereinafter referred to as an X1 sensor and an X2 sensor) disposed between the tilt plate 201 and the XY plate 301. It is measured. The position in the Y-axis direction of the X-Y plate 301 is measured by one capacitance sensor 328 (hereinafter referred to as Y sensor) disposed between the tilt plate 201 and the X-Y plate 301. Semi-closed position control of the top table 2-2 is performed based on the positional information in the X-Y plane measured by these X1 sensor 326, X2 sensor 327, and Y sensor 328. FIG.

As described above, the top table 202 is fixed to the X-Y plate 301, and the tilt plate 201 in the tilt stage is displaceable in the Z-axis direction, the θx-axis direction, and the θy-axis direction. In addition, the X-Y plate 301 in the X-Y stage can be displaced together with the tilt plate 201 and can be displaced in the X-axis direction, Y-axis direction, and θz-axis direction independently of the tilt plate 201. As a result, the top table 202 can move in six degrees of freedom (X-axis direction, Y-axis direction, Z-axis direction, θx-axis direction, θy-axis direction, and θz-axis direction).

In addition, the position measurement (X-axis direction, Y-axis direction, (theta z-axis direction) of the XY stage is X mirror 325 (FIG. 1) and X-axis direction which are extended in the Y-axis direction attached to the top table 202. This is done by a Y mirror 326 (FIG. 3) and a laser interferometer (not shown) extending in the direction. Based on the positional information obtained by the position measurement, full closed control of six degrees of freedom (X-axis direction, Y-axis direction, Z-axis direction, θx-axis direction, θy-axis direction, and θz-axis direction) is performed. Further, the position can be measured by the laser interferometer in the θx-axis direction and the θy-axis direction, and position control can be performed by the positional information from the laser interferometer in all except the Z-axis direction based on this measured value. In this case, however, it is necessary to consider that a problem such as cost up occurs because the mirror is enlarged and the optical parts of the laser interferometer increase.

Next, the fine motion stage apparatus which concerns on 2nd Embodiment of this invention is demonstrated. The fine motion stage apparatus which concerns on 2nd Embodiment adds the following improvements with respect to the fine motion stage apparatus which concerns on 1st Embodiment.

Since the movement stroke is large with respect to the tilt stage part, the micro-movement stage apparatus which concerns on 1st Embodiment is difficult to ensure high rigidity by the characteristic of a piezo actuator. This is because the fine motion stage apparatus according to the first embodiment has a structure in which two piezo actuators are connected by two stages because the stroke is increased. That is, the piezo actuator having a double structure has two springs connected in series as the rigid model, and the rigidity of the driving direction decreases as the stroke increases.

In addition, in the fine motion stage apparatus according to the first embodiment, the mass is increased in order to achieve high rigidity of the X-Y stage portion. For this reason, the load mass of a tilt stage increases, and as a result, an intrinsic value falls, and response performance falls, and there exists room for improvement in the settling time at the step response of several micrometers.

In addition, the fine motion stage apparatus according to the first embodiment has room for improvement in vibration damping performance because there is almost no damping element against vibration. That is, it takes time to correct after the movement of the stage, and it takes time to correct the vibration due to disturbance.

Therefore, the fine motion stage apparatus which concerns on 2nd Embodiment is characterized by providing the damper corresponding to a vacuum and non-magnetic in order to raise vibration damping performance.

9-19, the fine motion stage apparatus which concerns on 2nd Embodiment is demonstrated. Although this fine motion stage apparatus may be used independently, it is usually combined with the X-Y stage apparatus which is a coarse motion stage apparatus. That is, this fine motion stage apparatus is also normally mounted in the X table or Y table in an X-Y stage apparatus.

Although the basic structure of the fine motion stage apparatus which concerns on this form is the same as that of the fine motion stage apparatus which concerns on 1st Embodiment, in order to achieve high rigidity of a Z-axis direction, stage stroke was changed from 360 micrometers to 180 micrometers. As a result, in the micro-movement stage apparatus which concerns on 1st Embodiment, the thing which connected two series of piezoelectric actuators for Z-axis drive by two stages is used, In the 2nd Embodiment, it is Z-axis drive. One piezo actuator is required.

This fine motion stage apparatus is called a XY-θz-axis stage (hereinafter referred to as an XY stage) to a Z-θx-θy-axis stage (hereinafter referred to as a tilt stage) constructed on the base plate 100 as a base body. Is different from the XY stage device).

First, the tilt stage will be described. 9 to 11, the tilt stage has a tilt plate 201. The tilt plate 201 includes three piezo actuators (piezo actuator elements) Z1, Z2, and Z3 arranged to extend in parallel to each other on the base plate 100, and the base plate 100 by a wedge stage described later. It is driven in the vertical direction (Z-axis direction or up-down direction) with respect to. Hereinafter, the axis driven in the Z-axis direction by the piezo actuator Z1 in the Z-axis direction and the axis driven in the Z-axis direction by the piezo actuator Z2 are driven in the Z-axis direction by the Z2 axis and the piezo actuator Z3. The axis is called Z3 axis.

Details of the structure and operation of the Z3 axis will be described. The piezo fixing block 130 is installed on the base plate 100. One end of the piezo actuator Z3 is fixed to the piezo fixing block 130 to drive the wedge stage 135. The wedge stage, also called a slide wedge, is a mechanism for converting a horizontal motion into a vertical motion as described above. In this embodiment, the wedge stage 135 is provided with a 45 degree orthogonal converter, and as shown in FIG. 17, the horizontal displacement input by the piezo actuator Z3 and the vertical displacement output of the wedge stage 135 are 1 piece. It is configured to be 1. The orthogonal converter comprises a combination of a first inclined block 135-1 having an inclined surface of 45 degrees on the upper surface side and a second inclined block 135-2 having an inclined surface of 45 degrees on the lower surface side. The first inclined block 135-1 has a guide portion for guiding the second inclined block 135-2. The second inclined block 135-2 is slidable along the inclined surface of the first inclined block 135-1 with its inclined surface guided by the guide portion of the first inclined block 135-1. As a result, when the first inclined block 135-1 is displaced in the horizontal direction, the second inclined block 135-2 slides accordingly and is displaced only in the vertical direction. In addition, the piezo actuator Z3 is supported by the support member 131 provided in the base plate 100.

By this wedge stage 135, the tilt hinge 137 fixed to the vertical movement part is driven to Z-axis direction. Then, the tilt plate 201 fixed to the tip of the tilt hinge 137 is driven in the Z1 axis direction. In addition, the tilt plate 201 has an opening 201a (FIG. 11) in the center. In the opening 201a, an X-Y plate 301 (Fig. 9) is combined. The top table 202 (FIG. 13) is fixed to the X-Y plate 301. The X-Y plate 301 and the top table 202 will be described later.

The Z1 axis and the Z2 axis have the same configuration as the Z3 axis, but are arranged so as to extend in the opposite direction with a predetermined interval from the Z3 axis. The Z1 axis has a piezo fixing block 110, a wedge stage 115, and a tilt hinge 117, and the Z2 axis has a piezo fixing block 120, a wedge stage 125, and a tilt hinge 127. The wedge stage 115 of the Z1-axis, the wedge stage 125 of the Z2-axis, and the wedge stage 135 of the Z3-axis are respectively arranged on the same circumference. In particular, the wedge stages 115, 125, 135 are disposed here at positions corresponding to the vertices of the equilateral triangle, that is, at an angle interval of 120 degrees. These three axes can be displaced in the same direction (here, the X axis direction), and the vertical movement portion can also be displaced in the same direction (here, the Z axis direction). As a result, the tilt plate 201 performs translational movement in the Z-axis direction. On the other hand, if the differential operation, that is, the difference in the displacement amount of each of the axes Z1, Z2, Z3, the tilt plate 201 is rotated in the θx axis direction, θy axis direction. As described above, the rotational motion in the θx-axis direction refers to the rotational motion around the X axis, and the rotational motion in the θy-axis direction means the rotational motion around the Y axis. Rotational motion in the θz-axis direction to be described later means rotational motion around the Z-axis.

The position in the Z-axis direction is measured by the capacitive sensor here. The capacitive sensor is disposed between the base table 100 and the top table 202 which is the last movable part above the tilt plate 201. Hereinafter, the Z1 axis capacitive sensor shown in FIG. 9 is referred to as Z1 sensor 207, the Z2 axis capacitive sensor is referred to as Z2 sensor 217, and the Z3 axis capacitive sensor is referred to as Z3 sensor 227. Each sensor 207, 217, 227 is provided in the position adjacent to the wedge stage 115, 125, 135, respectively. The measuring principle of the capacitive sensor is as described above.

In this embodiment, the height of the top table 202 which is the last movable part is measured by these Z1 sensor 207, Z2 sensor 217, and Z3 sensor 227, and position control of the top table 202 is based on a measurement result. (Full closed control) is performed.

Usually, in the tilt stage, the height position of the tilt plate 201 is measured from the base plate 100, and position control (semi-closed control) is performed based on the measurement result. However, this method cannot measure the positional error in the Z-axis direction when the X-Y plate 301 moves in the X-Y direction. This means that the positions of the Z-axis direction, the θx-axis direction, and the θy-axis direction of the top table 202 cannot be controlled. However, the arrangement of the Z-axis position measuring instrument in this embodiment enables position control in the Z-axis direction, the θx-axis direction, and the θy-axis direction of the top table 202.

The guide system of the tilt stage includes a tilt hinge 117, 127, 137 attached to each wedge stage 115, 125, 135, and a Z-axis direction mounted between the base plate 100 and the tilt plate 201. It is constituted by leaf springs 208, 218 and 228 which are only displaceable (see Fig. 11, except 208 see Fig. 18). These leaf springs 208, 218, and 228 constitute a rigid guide system that constrains the motion in the X-Y plane of the tilt plate 201, which is impossible to realize only by the guide portion of the wedge stage. In addition, the leaf springs 208, 218, 228 are respectively provided through the spring mounting parts 208-1 (refer FIG. 18), 218-1, 228-1 with which the base plate 100 was equipped.

In this embodiment, as shown in FIG. 9, dampers 219, 229, and 239 are provided as Z-axis attenuators on the supports 219-1, 229-1, 239-1, and 249-1 fixed to the base plate 100. , 249). Each damper has a piston rod, and as shown in FIG. 12, the tip of a piston rod is made to contact the lower surface of the top table 202. As shown in FIG. Here, four dampers 219, 229, 239, and 249 are provided at positions close to the outer periphery of the top table 202, and two are particularly provided at positions close to the wedge stage 135. This is a balance consideration, and at least three dampers may be disposed, and in some cases, five or more dampers may be used.

As described above, the tips of the piston rods of the dampers 219, 229, 239, and 249 are in contact with the bottom surface of the top table 202. With this arrangement, when the top table 202 is rotated in the θx-axis and θy-axis directions, two or more dampers are necessarily pushed in, so that an effective damping action by the damper is obtained.

Regarding the movement in the Z-axis direction of the top table 202, all dampers 219, 229, 239, and 249 exhibit damping performances in the downward direction. In addition, when the top table 202 moves upward in a horizontal state, effective damping cannot be expected. However, the top table 202 does not move in the Z-axis direction in a completely horizontal state, and always involves operations in the θx-axis and θy-axis directions. Therefore, effectively the damping action is obtained even when the top table 202 moves in any of the Z-axis direction, the θx-axis direction, and the θy-axis direction.

Next, with reference to FIG. 13, the X-Y stage is demonstrated. The top table 202 is fixed to the upper surface side of the X-Y plate 301. As shown in FIG. 13, the X-Y plate 301 is assembled to the opening 201a of the center part of the tilt plate 201. As shown in FIG. The XY plate 301 can be displaced in the Z-axis direction, the θx-axis direction, and the θy-axis direction together with the tilt plate 201, but is independent of the tilt plate 201 in the X-axis direction, the Y-axis direction, and the θz-axis direction. Displacement is enabled. That is, the X-Y plate 301 is driven by two X1 piezo actuators 302 and X2 piezo actuators 303 which extend in parallel to each other in the X axis direction with respect to the X axis direction. As shown in FIG. 9, the X1 piezo actuator 302 and the X2 piezo actuator 303 are provided at regular intervals, and one end side thereof is tilt plate 201 through the mounting plates 302-1 and 303-1, respectively. Is fixed to the other end and is connected to the XY plate 301. On the other hand, the X-Y plate 301 is driven by one Y piezo actuator 304 extending in the Y-axis direction with respect to the Y-axis direction. The Y piezo actuator 304 is also fixed at one end to the tilt plate 201 via the mounting plate 304-1, and the other end thereof is connected to the X-Y plate 301.

The guide system of the X-Y stage is as follows. As shown in FIG. 15, in the guide system in the XY plane, the X1 hinge 312 fixed to one end of the X1 piezo actuator 302 is fixed to the mounting plate 302-1 and the X1 piezo actuator 302 An X1 hinge 311 fixed to the other end is connected to the XY plate 301. Similarly, an X2 hinge 314 (not shown) fixed to one end of the X2 piezo actuator 303 is fixed to the mounting plate 303-1, and an X2 hinge 313 (mido) fixed to the other end of the X2 piezo actuator 303. Is connected to the XY plate 301. On the other hand, the Y hinge 316 (not shown) fixed to one end of the Y piezo actuator 304 is fixed to the mounting plate 304-1, and the Y hinge 315 (mido fixed to the other end of the Y piezo actuator 304). Is connected to the XY plate 301.

As shown in FIG. 13, the guide system in the Z-axis direction includes three main link hinges 321, 322, and 323 and two portions provided between the XY plate 301 and the tilt plate 201. ) Is realized by the link hinges 324 and 325. Referring to Fig. 17, one of these link hinges, for example, the main link hinge 321, will be described. The link hinge block 321-1 is provided on the tilt plate 201 to vertically extend downward. The link hinge block 321-1 is provided with a hinge 321-2 extending upward therefrom and connected to the X-Y plate 301. The hinge 321-2 has a known spherical joint coupling and supports the X-Y plate 301 so as to be displaced in the X-Y plane, but to provide high rigidity in the Z-axis direction. The primary link hinges 322 and 323 and the secondary link hinges 324 and 325 also have exactly the same structure. 17 shows only the components required for explanation. 9, the main link hinge 322 which consists of the link hinge block 322-1 and the hinge 322-2 is shown.

As shown in FIG. 13, the three main link hinges 321, 322, 323 are provided at positions corresponding to the vertices of a triangle, here an isosceles triangle, and the two sub link hinges 324, 325 are the main link hinges. 321 is provided on both sides. The main link hinges 321 to 323 and the sub link hinges 324 and 325 have a function of enabling displacement in the XY plane of the XY plate 301 and have great rigidity in the Z-axis direction. . Thereby, rigidity improves significantly compared with the conventional fine motion stage apparatus.

The operation of the X-Y stage will be described. When the X1 piezo actuator 302 and the X2 piezo actuator 303 operate in the same direction, the X-Y plate 301 performs translational movement in the X-axis direction. When the X1 piezo actuator 302 and the X2 piezo actuator 303 are differentially operated, i.e., have a difference in displacement amount, the X-Y plate 301 operates in the? Z-axis direction. On the other hand, when the Y piezo actuator 304 is operated, the X-Y plate 301 translates in the Y axis direction.

Referring to FIG. 13, the position in the X-axis direction of the XY plate 301 may include two capacitive sensors 326 and 327 (hereinafter referred to as X1 sensor, disposed between the tilt plate 201 and the XY plate 301). X2 sensor). The position in the Y-axis direction of the X-Y plate 301 is measured by one capacitance sensor 328 (hereinafter referred to as Y sensor) disposed between the tilt plate 201 and the X-Y plate 301. Semi-closed position control of the top table 2-2 is performed based on the positional information in the X-Y plane measured by these X1 sensor 326, X2 sensor 327, and Y sensor 328. FIG.

Next, in addition to FIG. 13, the attenuator of an X-axis direction and a Y-axis direction is demonstrated with reference also to FIG. Two holder stands 251 and 252 are fixedly arranged on the base plate 100 at intervals. On these holder stands 251 and 252, a damper holder 260 having a rectangular frame shape is fixed. The holder stands 251 and 252 are arranged at intervals because the piezo actuator Z3 passes between them. On the other hand, the X-Y plate 301 has an opening 301a (see Fig. 9) at the center. The top plate 202 corresponding to the opening 301a is also provided with an opening 202a (Fig. 13). On the inner wall of the opening 202a, a damper ring 270 having an inner diameter that is slightly smaller than this and slightly larger than the damper holder 260 is mounted. In the damper holder 260, two dampers 261 and 262 are attached to the damper holder 260 in the opposite direction on the coaxial in the X-axis direction. In the damper holder 260, two dampers 263 and 264 are mounted on the coaxial in the Y-axis direction in opposite directions as the Y-axis direction attenuators. The piston rods of the dampers 261 to 264 are in contact with the inner diameter surface of the damper ring 270.

When the top table 202 is moved in the X axis direction and the Y axis direction by the arrangement of the four dampers 261 to 264 as described above in the same XY plane, at least one damper must be pushed in. State, and effective attenuation is obtained. Also, the center of the damper holder 260 and the center of the load (load of movable parts such as the top table and the mirror) do not coincide with the rotational movement in the θz-axis direction of the top table 202. 261 to 264), it is arranged and configured to act as a translational displacement and exhibit damping performance.

Moreover, what is necessary is just to arrange | position at least three about the dampers of an X-axis direction and a Y-axis direction. That is, in the above example, four dampers are arranged in the same plane at an angular interval of 90 degrees. However, even when three dampers are disposed in the same plane (preferably at an angle interval of 120 degrees), it is possible to exhibit damping performance in the X-axis direction and the Y-axis direction.

The dampers 219, 229, 239, 249, and 261 to 264 all use the same thing. The structure of the damper is generally called a shock absorber, and various types are commercially available. An example is shown in FIG.

In FIG. 16, 401 is a piston rod, 402 is a sleeve, 403 is a plug, 404 is an accumulator, 405 is a spring, 406 is an oil, 407 is a piston ring, 408 is a collar 409 is a rod packing, 410 is an O-ring, 411 is a small screw and 412 is a hex nut. Usually, when using this kind of shock absorber, the tip of the piston rod is rigidly fixed to the attenuated element. However, the present invention is characterized in that the tip of the piston rod is not rigidly fixed.

In the present invention, nonmagnetic materials such as titanium, phosphorus bronze and beryllium copper are used as structural materials in order to cope with vacuum and nonmagnetic environments. In addition, the base oil of vacuum grease is used for the damping oil. As a result, vacuum and nonmagnetic correspondence are realized at a minimum cost without changing the structure such as vacuum sealing by bellows.

For reference, Fig. 18 shows piezo actuators Z1-Z3 for the Z1-axis Z3-axis and its related elements, main link hinges 321-323 and sub-link hinges 324, 325, dampers 219, 229, 239. 249 and dampers 261 to 264 are shown in plan view. 19, the support structure of the dampers 261-264 is shown by side sectional drawing. However, each element shown in FIG. 18, FIG. 19 does not necessarily correspond to each element shown in FIG. The opening 202a of the top table 202 may not be provided.

As described above, the top table 202 is fixed to the X-Y plate 301, and the tilt plate 201 in the tilt stage is displaceable in the Z-axis direction, the θx-axis direction, and the θy-axis direction. In addition, the X-Y plate 301 in the X-Y stage can be displaced together with the tilt plate 201 and can be displaced in the X-axis direction, Y-axis direction, and θz-axis direction independently of the tilt plate 201. As a result, the top table 202 can move in six degrees of freedom (X-axis direction, Y-axis direction, Z-axis direction, θx-axis direction, θy-axis direction, and θz-axis direction).

The position measurement (X-axis direction, Y-axis direction, θz-axis direction) of the XY stage is Y mirror extending in the Y-axis direction and Y-axis extending in the Y-axis direction mounted on the top table 202. The mirror 332 (see FIG. 13) and a laser interferometer (not shown) are used. Based on the positional information obtained by the position measurement, full closed control of six degrees of freedom (X-axis direction, Y-axis direction, Z-axis direction, θx-axis direction, θy-axis direction, and θz-axis direction) is performed. Further, the position can be measured by the laser interferometer in the θx-axis direction and the θy-axis direction, and position control can be performed by the positional information from the laser interferometer in all except the Z-axis direction based on this measured value. In this case, however, it is necessary to consider that a problem such as cost up occurs because the mirror is enlarged and the optical parts of the laser interferometer increase.

As mentioned above, although two embodiment of this invention was described, each said component is made from a nonmagnetic material. In addition, although the said fine motion stage apparatus is applied to what is arrange | positioned and used in the vacuum container of about ^10-4 (Pa) degree vacuum degree with a coarse motion stage apparatus, it cannot be overemphasized that it can also be used in air | atmosphere. none. That is, the operating environment of the fine movement stage apparatus according to the present invention is not limited under a vacuum environment, it is also operable in an atmosphere such as air, N _2. For this reason, the application field of the micro-movement stage apparatus by this invention is applicable also to a semiconductor manufacturing apparatus and a liquid crystal manufacturing apparatus, and is a stage apparatus which requires high-precision positioning in the micro range of a laser processing machine, a machine tool, etc. Applicable to the first half.

According to the first aspect of the present invention, even when a load of more than 5 kg, for example 25 kg, is mounted on the movable part, it is possible to provide a six-degree-of-freedom fine motion stage that can realize high stopping stability and high responsiveness. Specifically, the fine motion stage apparatus according to the first aspect assumes a load of 25 kg and designs a high rigidity guide system so that in the XY stage part, 150 Hz (5 times as conventional) is used. It is possible to secure. Thereby, static stability improved to 5-6 nm (3delta value). Moreover, in the step response of several micrometers, the settling time 21-35 msec was implement | achieved.

According to the 2nd aspect of this invention, in addition to the effect of the fine motion stage apparatus by a 1st aspect, the following effects are acquired. That is, in the conventional micro-movement stage apparatus, since there is almost no attenuation element with respect to vibration, it took about 800-1200 msec until the vibration by the disturbance attenuated in the state which does not perform position control. In contrast, in the fine motion stage apparatus according to the second aspect, vibration was attenuated at 70 to 115 msec which is about 1/10 by mounting the attenuator. By this effect, the stop stability of the tilt stage became 9 nm (3δ) which is 1/6 or less of the conventional one, and the settling time at the time of several micrometer step movement also realized 15-30 msec. The X-Y stage portion was also improved to 3.5-4.5 nm (3δ) of static stability.

The fine motion stage device is often mounted in a coarse motion stage device having a large stroke in the X-Y direction and performing a step and repeat motion of high acceleration and deceleration. The high acceleration / deceleration motion of the coarse motion stage device is disturbance itself in the fine motion stage device. By improving the damping performance against such disturbances, it is possible to achieve high throughput. In addition, stability against vibrations from the vacuum exhaust system, vibrations when opening and closing the gate valve, and the like are greatly improved.

Claims (13)

A fine motion stage device comprising a tilt stage and an X-Y stage constructed on a base body, The tilt stage has a tilt plate and a transducer mechanism for converting a motion parallel to the base body into a motion in the Z-axis direction perpendicular to the base body by a combination of a first piezo actuator and a wedge stage. At least three are provided between a plate and the said base body, The XY stage includes at least two second piezo actuators having an XY plate coupled to the tilt plate and extending in parallel to one of the X and Y axis directions to drive the XY plate at at least two points. And a third piezo actuator extending in the other direction in the X-axis direction and the Y-axis direction to drive the XY plate. The method of claim 1, By arranging the at least three transducer spheres at equal angle intervals on the same circumference, the tilt plate can be displaced in the Z-axis direction, in the θx-axis direction around the X-axis, in the θy-axis direction around the Y-axis, The XY plate can be displaced together with the tilt plate and can be displaced in the X-axis direction, the Y-axis direction, and the θz-axis direction around the Z-axis independently of the tilt plate. . The method of claim 1, Between the said tilt plate and the said XY plate, the link hinge which guides the movement in the XY plane of this XY plate, and gives high rigidity to the direction perpendicular | vertical to the said base body is provided in several places. Fine moving stage device, characterized in that. The method of claim 1, A fine movement stage apparatus is provided between the said tilt plate and the said base body in the several place to restrain the movement in the X-Y plane of this tilt plate. The method of claim 1, A fine motion stage apparatus, wherein a tilt hinge is interposed between an upper portion of the moving part in the Z-axis direction and the tilt plate in the transducer tool. The method of claim 1, The first piezo actuator is a micro-movement stage device characterized in that two piezo actuator elements extending in parallel to each other are combined so that their strokes are added by two stages. The method of claim 1, On the X-Y plate, a fine table apparatus, characterized in that a top table for mounting the workpiece. The method of claim 7, wherein And a plurality of Z-axis attenuators having a damping effect in the Z-axis direction between the base body and the top table. The method of claim 7, wherein And between said base body and said X-Y plate at least three attenuators having a damping action in the X-axis direction and in the Y-axis direction so as to be in the same X-Y plane. The method of claim 7, wherein The tilt plate has a first opening in a central portion thereof, and the X-Y plate having a second opening smaller in this first opening is combined; The lower surface of the top table corresponding to the second opening is provided with a damper ring having a size corresponding to the second opening, The damper ring is provided with a damper holder which is slightly smaller than the inner diameter of the damper ring through a stand provided in the base body. Between the damper holder and the damper ring, at least two X-axis attenuators having a damping action in the X-axis direction are provided to act in opposite directions on the same axis and at least two having a damping action in the Y-axis direction. A fine motion stage device comprising: a Y-axis attenuator mounted on a coaxial axis in opposite directions. The method according to any one of claims 8 to 10, The damper comprises a damper made of a nonmagnetic material containing a base oil of vacuum grease as a damper oil for damping, and including a return spring and a piston rod. Stage device. The method of claim 8, And the Z-axis damper is disposed so that the tip of the piston rod is in contact with the bottom surface of the top plate. The method of claim 9 or 10, And the X-axis damper and Y-axis damper are arranged so that the tip of the piston rod is in contact with the damper ring.