KR102229484B1 - Work stage and exposure apparatus - Google Patents

Abstract

[Problem] Provides an inexpensive work stage that can sufficiently adsorb and hold even a deformed work without causing damage to the work, and easily cope with work of different sizes.
[Solving means] The shrinking sheet 3 provided on the work holding surface of the stage main body 1 on which the plate-shaped work W is placed is in the shape of a frame surrounding a region in which the vacuum suction holes 21 for work are provided. When the work W is placed on the work holding surface and is adsorbed by vacuum suction through the work vacuum suction hole 21, the shrinking sheet 3 is sandwiched between the work W and the stage body 1 . The shrinking sheet 3 has a shape that extends along the periphery of the work W, and contracts in the thickness direction by elasticity according to the deformation of the work W, and is in close contact with the work W.

Description

Work stage and exposure apparatus {WORK STAGE AND EXPOSURE APPARATUS}

The present invention relates to a work stage for holding a work as an object to be processed in a predetermined position, and to an exposure apparatus equipped with this kind of work stage.

In an apparatus that performs various processes, it is often necessary to hold an object to be processed (hereinafter, referred to as a work) in a predetermined position. At this time, when the work is in the shape of a plate, it is often carried and held on a large member (hereinafter referred to as a stage) having a flat surface, and such a stage is referred to as a work stage.

The work stage is often provided with a mechanism for adsorbing a work in order to ensure retention of the work, and a vacuum adsorption mechanism for adsorbing by vacuum is often employed as this mechanism. A vacuum suction hole is formed on the work holding surface of the work stage, and a vacuum exhaust path communicating with the vacuum suction hole is provided in the work stage. A vacuum pump is connected to the vacuum evacuation path, and the work is held on the work stage by vacuum suction through the vacuum suction hole while the work is disposed in a state in which the vacuum suction hole is blocked.

Japanese Patent Publication No. 2009-109553 Japanese Patent Publication No. 2011-81156 Japanese Patent No. 4589198

In a work stage equipped with such a vacuum adsorption mechanism, there is a problem that the work is deformed, which is the cause that vacuum adsorption cannot be sufficiently performed.

For example, in an exposure apparatus for printed circuit boards that exposes a circuit pattern to a substrate, a work stage is used to hold the substrate at a predetermined position with respect to the exposure optical system. Such an exposure apparatus for printed circuit boards may expose a thin flexible substrate formed of polyimide, polyester, or the like. This kind of substrate is susceptible to the heat treatment in the previous step, and is curved or curved when viewed from the side. Further, even in the case of a rigid substrate such as a glass epoxy, when the substrate has a multilayer structure, warping or curvature tends to occur in the periphery of the substrate as the process for lamination is repeated due to differences in thermal expansion coefficients between materials, etc.

In the case of a work in which deformation such as warping or curvature has occurred in this way, when placed on the work stage, the vacuum adsorption hole cannot be sufficiently closed, and vacuum adsorption cannot be performed or adsorption becomes insufficient because the vacuum leaks. As a result, the work is in a state in which the work can be displaced during processing. In the case of the exposure apparatus, the displacement of the workpiece during exposure directly leads to a decrease in the positional accuracy of the pattern to be exposed, and affects the performance of the product. Therefore, it is necessary to sufficiently vacuum-adsorb even the work in which the deformation has occurred.

[0003] As a conventional configuration for sufficiently vacuum adsorption even for deformed work, a clamp mechanism for pressing the periphery of the work from the upper side is often employed. However, this kind of mechanism has a drawback that it is easy to damage the work. In addition, since the periphery of the work is covered from the upper side, if processing (e.g., exposure) needs to be performed on the periphery as well, the clamp needs to be retracted during processing, and the original deformed posture when retracted. It may return to and cause a vacuum leak. In addition, this kind of apparatus tends to be complicated, the apparatus becomes large, and it tends to be expensive.

In addition, under the demand for small quantity production of multiple products, it is often necessary to process work of different sizes with one device. In this case, in the case of the clamp mechanism, it is difficult to cope with workpieces of different sizes, and in order to make this possible, there is a problem in that the mechanism becomes more complicated or expensive.

The invention of the present application was made to solve each of the above problems. In addition to sufficiently adsorbing and holding the deformed work, there is no problem of damaging the work at this time, and it is also possible to cope with work of different sizes. It aims to make it easy and can be realized at a lower cost.

In order to solve the above problems, the invention described in claim 1 of this application is a work stage for holding a plate-shaped work,

A stage body having a vacuum suction hole for a workpiece on the workpiece holding surface, and

It is a work stage equipped with an exhaust system for adsorbing the work by vacuum suctioning the work vacuum suction hole when the work is in contact with the work at the holding position set on the work holding surface,

A shrink sheet is installed on the workpiece holding surface,

The shrinking sheet has a shape surrounding the area outside the area where the vacuum suction hole for the work is provided, and is sandwiched between the work and the work holding surface of the stage body when the work is in contact with the work holding surface at the holding position. It is a shape extending along the periphery of the work,

The shrinking sheet has flexibility due to elasticity that shrinks in the thickness direction when the work in contact with the work holding surface is vacuum-adsorbed and adheres to the work,

The shrinking sheet has a configuration in which it is attached to the work holding surface so as to be detachable.

In addition, in order to solve the above problem, the invention according to claim 2 is, in the configuration of claim 1, wherein the shrink sheet is provided in the entire circumference of the periphery of the work in contact with the work holding surface at the holding position. It has a configuration that it has a shape overlapping with.

In addition, in order to solve the above problem, the invention according to claim 3, in the configuration of claim 1, wherein the contraction sheet is a region that does not partially overlap in the peripheral portion of the work in contact with the work holding surface at the holding position. It is a shape having, and has a configuration that the length in the circumferential direction of the non-overlapping region is 10 mm or less.

In addition, in order to solve the above problem, the invention according to claim 4, in the configuration of claim 1, 2 or 3, is an average of the shrinking sheet contracted in the thickness direction when the work contacting the work holding surface is vacuum-adsorbed. The thickness is 0.5 mm or less.

In addition, in order to solve the above problems, the invention according to claim 5 is, in any one of the above-mentioned claims 1 to 4, wherein the shrink sheet is provided in a state attached to a frame, and the frame is It has a configuration in which the contraction sheet is fixed at a position outside the workpiece when abutting against the holding surface and vacuum-adsorbed.

In addition, in order to solve the above problem, the invention according to claim 6, in any one of the above-mentioned claims 1 to 5, wherein the stage main body has a flat surface outside the region where the vacuum suction hole for the work is provided. In addition, the shrinkable sheet has a configuration that is provided on the flat surface.

Moreover, in order to solve the said subject, the invention described in Claim 7 is the invention of an exposure apparatus,

Light source,

An optical system that projects light from a light source as an image of a predetermined pattern,

It is equipped with the work stage in any one of Claims 1-6,

The holding position has a configuration called a projection position of an image of a predetermined pattern by an optical system.

In addition, in order to solve the above problem, the invention according to claim 8, in the configuration of claim 7,

When the work in contact with the work holding surface is vacuum-adsorbed, the average thickness of the contracted sheet contracted in the thickness direction is 1/2 or less of the depth of focus when the optical system projects the image.

As described below, according to the invention described in claim 1 of this application, when the work is vacuum-adsorbed on the work stage, the shrinking sheet is compressed and contracted in the thickness direction by the periphery of the work. The shrinking sheet and the work are in close contact, so that errors in vacuum adsorption are prevented. At this time, since it is not necessary to press the work from the opposite side like a clamp mechanism, the work is not damaged, has a simple structure, and is inexpensive.

Further, according to the invention according to claim 4, in addition to the above effect, since the average thickness of the contracted shrink sheet is 0.5 mm or less, the curvature of the vacuum-adsorbed work is reduced.

Further, according to the invention according to claim 5, in addition to the above effect, since the shrink sheet is attached to the frame, handling and positioning of the shrink sheet becomes easy. Since the frame holds the shrink sheet outside the area where the shrink sheet and the work overlap, the frame does not impede the close contact between the shrink sheet and the work.

Further, according to the invention according to claim 6, in addition to the above effects, since the shrinking sheet is provided on the flat surface of the stage main body, an effect that it is easy to cope with workpieces of different shapes and sizes is obtained.

Further, according to the invention according to claim 7, the above effect can be obtained in an exposure apparatus for exposing a work.

Further, according to the invention according to claim 8, in addition to the above effect, since the average thickness of the contracted shrink sheet is 1/2 or less of the depth of focus of the optical system, the above effect can be obtained while preventing image blur.

1 is a schematic front cross-sectional view of a work stage according to an embodiment.
2 is a perspective schematic diagram of the work stage shown in FIG. 1.
3 is a perspective schematic diagram of a main part of the work stage shown in FIG. 1.
Fig. 4 is a schematic cross-sectional view showing the flexibility of the shrinking sheet, and is a schematic cross-sectional view taken along X-X in Fig. 2.
Fig. 5 is a schematic cross-sectional view showing the flexibility of the shrinking sheet, and is a schematic cross-sectional view taken along line Y-Y in Fig. 2.
6 is a schematic front cross-sectional view of an exposure apparatus according to an embodiment.

Next, an embodiment (hereinafter, an embodiment) for carrying out the present invention will be described.

1 is a schematic front cross-sectional view of a work stage according to an embodiment, FIG. 2 is a perspective schematic view of the work stage shown in FIG. 1, and FIG. 3 is a perspective schematic view of a main part of the work stage shown in FIG. 1.

The work stage of the embodiment shown in FIGS. 1 to 3 is a stage that holds a plate-shaped work W, and includes a stage main body 1. The stage main body 1 is a large, square member in plan view. In this embodiment, the stage main body 1 is supposed to hold the work W in a horizontal posture, and the upper surface, which is a horizontal flat surface, serves as the work holding surface.

1 to 3, the stage main body 1 has a plurality of vacuum suction holes 21 for work. On the upper surface of the stage main body 1, the holding position of the work W is set, and the vacuum suction hole 21 for the work is provided at the holding position.

As shown in Fig. 1, in the stage main body 1, a work exhaust path 22 communicating with each work vacuum adsorption hole 21 is formed. The work stage is provided with an exhaust system 2 including a vacuum pump (not shown), and the work exhaust pipe 23 of the exhaust system 2 is connected to the work exhaust path 22.

In the work stage of this embodiment, the shrink sheet 3 is provided in consideration of the problem of deformation of the work W. The shrink sheet 3 has a square frame shape, as shown in FIGS. 2 and 3. In addition, in FIG. 3, illustration of some members is abbreviate|omitted in order to make the whole shape of the shrink|shrink sheet 3 easy to understand.

The shrinking sheet 3 is provided in a state placed on the upper surface of the stage main body 1. The placed position is a predetermined position in relation to the holding position of the work W.

In this embodiment, the work W is in the shape of a square plate. The holding position is set as, for example, a position where the held work W occupies a square area concentric with the center of the stage main body 1. The holding position is indicated by a square imaginary line R in Figs. 2 and 3. The work W is mounted with high precision so that its outline matches the imaginary line R. The area surrounded by the imagination line R is hereinafter referred to as a holding area.

When the work W is placed in the holding position, the shrink sheet 3 is installed at a position where the periphery of the work W overlaps, and therefore, between the work W and the work holding surface of the stage main body 1 It is inserted into the state. More specifically, the inner edge of the shrink sheet 3 is positioned inside the holding region R, and the outer edge is positioned outside the holding region R. For this reason, when the work W is arranged so that the contours coincide with the holding region R, the shrinking sheet 3 is sandwiched between the work W and the work holding surface of the stage main body 1, and the work ( The entire circumference of the circumferential edge of W) overlaps with the work W. Accordingly, the shrink sheet 3 has a rectangular frame shape in which the inner edge and the outer edge are parallel to each side (hereinafter, such a shape is referred to as a frame shape in the present specification).

As such shrinkable sheet 3, in this embodiment, one made of silicone is used. The thickness is preferably about 0.1 to 10 mm, more preferably about 0.5 to 2 mm.

The shrinking sheet 3 has the flexibility to shrink in the thickness direction when the work W in contact with the work holding surface is vacuum-adsorbed to adhere to the work W, and this contraction prevents vacuum leakage. . Hereinafter, this point will be described with reference to FIGS. 4 and 5. 4 and 5 are cross-sectional schematic views showing the flexibility of the shrink sheet 3. 4 is a schematic cross-sectional view taken along X-X in FIG. 2, and FIG. 5 is a schematic cross-sectional view taken along Y-Y. 4(1) and 5(1) show the state before the work W is held on the work stage, and Figs. 4(2) and 5(2) show that the work is held on the work stage and vacuum Shows the adsorbed state.

The work W is placed and held in the holding position of the stage main body 1. At this time, in the holding position, the work W contacts the stage main body 1, and the vacuum suction hole 21 for work is closed. Then, the vacuum suction hole 21 for the work is vacuumed by a vacuum pump (not shown) installed in the exhaust system 2, so that the work W is vacuumed to the stage main body 1 as shown in Fig. 4(2). do.

At this time, as shown in Fig. 5(2), the shrinking sheet 3 overlapping the periphery of the work W shrinks in the thickness direction according to the shape of the deformed work W. The cross-sectional shape of the contracted sheet 3 after contraction becomes a shape that mimics the cross-sectional shape of the deformed work W, and the work W and the contraction sheet 3 are in close contact with each other. As a result, the space inside the shrink sheet 3 becomes a closed space (a sealed space) by the close contact between the work W and the shrink sheet 3, and vacuum leakage is prevented.

As described above, the flexibility of the shrink sheet 3 is such that the work W compresses the shrink sheet 3 and adheres to it when vacuum is sucked. The shrink sheet 3 of the embodiment is made of silicone, but what is sold as a so-called silicone rubber sheet can shrink by the suction force when the work W is vacuum-adsorbed, and the shrink sheet in the embodiment ( It can be used as 3). For example, an SR sheet manufactured by Tigers Polymer Co., Ltd. can be used as the shrinking sheet 3 in the embodiment. In addition, the suction force added to the work W at the time of vacuum adsorption is generally about -50 kPa to -80 kPa, and it can also be said that it is the flexibility to contract with such a force.

The thickness of the shrinking sheet 3 is selected according to the amount of deformation of the work W in the thickness direction. It is necessary that the thickness of the shrinking sheet 3 exceeds the maximum amount of deformation in the thickness direction of the work W. For example, when the thickness of the work W is 0.3 mm and the maximum amount of deformation is 0.7 mm, the thickness of the shrink sheet 3 is about 1 mm.

In addition, the compression of the shrinkable sheet 3 due to the deformation of the work W needs to be elastic deformation, not plastic deformation. However, the shrinking sheet 3 only needs to be restored to its original state until the next workpiece W is vacuum-adsorbed, and thus may exhibit so-called low repulsion elasticity.

This shrinking sheet 3 is attached to the stage body 1 in a state that does not displace (the position is fixed). In this embodiment, the shrink sheet 3 is vacuum-adsorbed on the stage main body 1. As shown in FIG. 1, the stage main body 1 is provided with a sheet vacuum suction hole 24. The sheet vacuum adsorption hole 24 communicates with an exhaust path 25 of a system different from the work vacuum adsorption hole 21, and exhaust and air release are controlled independently. That is, to the sheet exhaust path 25 formed in communication with the sheet vacuum suction hole, a sheet exhaust pipe 26 of a system different from the work exhaust pipe 23 is connected. On the exhaust pipe 26 for a seat, an on-off valve and an atmospheric release valve are provided separately from the one on the exhaust pipe 23 for a work.

In addition, in this embodiment, as shown in FIGS. 1 and 2, the shrink sheet 3 is provided in a state attached to the frame 31. The shrink sheet 3 does not necessarily have the frame 31, but the frame 31 is provided for ease of handling and for positioning.

The frame 31 is a plate-like member made of metal such as aluminum and stainless steel. In this embodiment, the frame 31 is also in the shape of a frame in accordance with the frame-shaped shrink sheet 3. The frame 31 has a thin thickness along the inner edge and a step is formed, and in this portion, the outer edge of the shrink sheet 3 is fixed. Fixation is performed by bonding with an adhesive material, for example.

The shape and size of the outer edge of the frame 31 are the same as the outline shape and size of the stage main body 1. Therefore, the alignment of the shrink sheet 3 is completed by placing the outer edge of the frame 31 on which the shrink sheet 3 is attached to the edge of the stage body 1 and placing it on the stage body 1. . Further, in order to further facilitate positioning, a plurality of positioning plates 32 are provided at the edge of the stage main body 1.

Vacuum adsorption for fixing the position of the above-described shrink sheet 3 is performed directly on the frame 31. In other words, the sheet vacuum suction hole 24 is formed at a position facing the frame 31 placed in alignment as described above, and the frame 31 is directly vacuum sucked. The shrinking sheet 3 may be directly vacuum-adsorbed, but if vacuum adsorption is repeated on the soft shrinkable sheet 3, it may wear out, and a problem may arise in terms of durability.

According to the work stage of the above embodiment, when the work W is vacuum-adsorbed onto the work stage, the shrinking sheet 3 is compressed and contracted in the thickness direction by the periphery of the work W as described above. Since this shrinkage depends on the shape of the work W in the thickness direction, even if the work W is deformed in the thickness direction, the contraction sheet 3 and the work W are in close contact with each other. For this reason, even with the deformed work W, an error of vacuum adsorption is prevented, and appropriate processing is performed without displacement in the work stage.

At this time, since it is not necessary to press the work W from the opposite side like a clamp mechanism, the work W is not damaged. In addition, since the above effect is achieved with a simple structure in which the shrinking sheet 3 is interposed between the work W and the stage body 1 at the circumferential edge of the work W, it is not large-scale and cost-effective. It also becomes a cheap thing.

Moreover, since the shrinkable sheet 3 is detachable, it is easy to cope with the case where the dimensional shape of the work W is different. That is, when the shape and/or size of the work W is different, the shrinking sheet 3 is replaced. After the vacuum adsorption by the sheet vacuum adsorption hole 24 is stopped, the contraction sheet 3 is separated from the stage body 1 with the frame 31. Then, the shrinking sheets 3 of different shapes and/or sizes are installed in the stage body 1 while being positioned by the frame 31 in the same manner, and the position is adjusted by vacuum adsorption in the vacuum suction hole 24 for the sheet. Fix it.

In addition, it is possible to implement a structure in which the frame 31 is detachably fixed to the stage main body 1 with a screw clamp, but the structure in which the position is fixed by vacuum adsorption makes the replacement work simple.

In the above embodiment, the shrink sheet 3 was made of silicone, but a sheet formed of another material may be used as long as it elastically deforms and has the flexibility to adhere to the work W. In addition, it is preferable that the material of the shrinkable sheet 3 is conductive. When the adsorption and holding of the work W and pickup of the processed work W are repeated, the shrinking sheet 3 may be charged (peel charging, etc.). The work W may be damaged due to charging in surrounding dust or electric discharge. When the shrinking sheet 3 is conductive, since the stage main body 1 is usually grounded, electric charges are easily removed even if charged, and a problem is unlikely to occur. Since various types of conductive silicone rubber sheets are commercially available, they can be appropriately selected and used from among them.

In addition, it is preferable that the average thickness of the contracted sheet 3 in a compressed state during vacuum adsorption of the work W is thin. This is because if the thickness at the time of compression is large, the work W is in a state in close contact with the stage body at the center portion, so that the curvature of the work W increases (the curvature decreases). Specifically, it is preferable that the average thickness of the compression sheet 3 at the time of compression is 0.5 mm or less.

It is preferable that the shrinkable sheet 3 overlaps the work W in the entire circumference of the periphery of the work W. However, even if there was a place where it does not overlap in part, the present invention can be implemented. For example, although the shrink sheet 3 is almost in the shape of a frame, it is assumed that there are at least one cut-off point. When the shrinking sheet 3 shrinks in the thickness direction, it may be desirable to allow elongation in the circumferential direction, and there may be cases where it is intentionally broken. Even in this case, if such a break is a short distance, the space inside the shrinking sheet 3 becomes a lower pressure than the atmosphere due to the decrease in conductance, so that the work W can be vacuum absorbed, and the deformed work W ), vacuum adsorption is also possible. The short distance can be, for example, 10 mm or less.

In addition, when deformation occurs only at a specific point in the circumferential direction in the work W, the shrink sheet may overlap the work W only at that place, and in this case, the shrink sheet needs to be in an endless circumferential shape. none.

In addition, the area where the shrink sheet 3 and the work W overlap is preferably including the peripheral edge of the work W, but may be implemented even if they overlap at the periphery slightly inside the circumferential edge. However, if the shrinkable sheet 3 overlaps the vacuum suction hole 21 for a work, the vacuum suction of the work W is inhibited. Therefore, it is necessary not to overlap the vacuum suction hole 21 for a work.

In addition, as described above, the shrink sheet 3 is preferably installed on a flat surface of the stage main body 1. The present invention can be practiced even in a structure in which a concave portion is installed in the stage body 1 and the shrink sheet 3 is dropped therein, and the thickness of the shrink sheet 3 is greater than the depth of the concave portion, but a different shape And/or it becomes difficult to respond to the size of the workpiece W.

Next, as an example of use of the work stage of the embodiment, an embodiment of the invention of an exposure apparatus equipped with a work stage will be described.

6 is a schematic front cross-sectional view of an exposure apparatus according to an embodiment. The exposure apparatus shown in FIG. 6 is an exposure apparatus for printed circuit boards as an example.

The exposure apparatus shown in FIG. 6 includes a work stage 4 that holds a work W at a predetermined position, and an exposure system that exposes the work W held on the work stage 4 by irradiating light of a predetermined pattern. (5) and a conveyance system 6 are provided. The exposure system includes a light source and an optical system that projects light from the light source as an image of a predetermined pattern.

The exposure apparatus of the embodiment does not specifically select a method of exposure, and any one of projection exposure, contact or proximity exposure, and further DI (direct imaging) exposure can be adopted. For example, in the case of projection exposure, the exposure system 5 includes a light source, a mask to which light from the light source is irradiated, and an optical system that projects the image of the mask onto the work stage 4, and the like. In the case of DI exposure, a configuration in which a plurality of exposure units including a laser light source and a spatial modulating element such as a digital mirror device (DMD) that spatially modulates light from the laser light source to form a pattern is provided is adopted.

As the conveying system 6, in this embodiment, a combination of a conveyor and a conveying hand is adopted. Transfer conveyors 61 and 62 are provided on both sides of the work stage 4. The transfer conveyors 61 and 62 are for carrying in and out of the work W to the work stage 4, and for convenience of explanation, the transfer conveyor 61 on the right is used as the first transfer conveyor, and the transfer on the left side Let the conveyor 62 be a 2nd conveying conveyor.

It operates in cooperation with each of the transfer conveyors 61 and 62, and transfer hands 63 and 64 are provided on both sides of the work stage 4. Also about the conveyance hands 63 and 64, for convenience of explanation, the right conveyance hand 63 is made into a 1st conveyance hand, and the left conveyance hand 64 is made into a 2nd conveyance hand.

Each of the conveyance hands 63 and 64 includes frames 631 and 641 and work suction pads 632 and 642 attached to the frames 631 and 641. Each of the frames 631 and 641 is provided with transport drive mechanisms 633 and 643. Details of the transport drive mechanisms 633 and 643 are omitted, but the frames 631 and 641 are linearly moved in the transport direction (left and right directions on the paper in Fig. 1) to position them at a predetermined position and move them in the vertical direction. It is a device that can be used. The apparatus is provided with a control part (not shown), and each conveyance drive mechanism 633, 643 is controlled by a control part (not shown).

A plurality of work suction pads 632 and 642 are provided at equal intervals so as to adsorb the work W at the periphery. A suction source for work (not shown) is connected to each of the work suction pads 632 and 642. The on-off of the work suction source is similarly controlled by a control unit (not shown).

Moreover, the lifting mechanism 40 is provided in the work stage 4. The lifting mechanism 40 is not only driven at the time of water supply of the work W, but is also used for the purpose of adjusting the distance of the work W with respect to the exposure system 5. The lifting mechanism 40 is constituted by a linear motion mechanism including a servomotor, and is controlled by a control unit.

Next, the operation of the exposure apparatus of this embodiment will be described.

First, the first conveying conveyor 61 conveys the work W to the lower position of the first conveying hand 63. Then, the first conveyance hand 63 descends, and the work W is adsorbed and held. After the 1st conveyance hand 63 rises by a predetermined distance, it moves in the horizontal direction and reaches the upper position of the work stage 4. After that, the first conveyance hand 63 descends a predetermined distance, and the work W is placed on the work stage 4.

The first conveyance hand 63 is in a state where the work W is slightly pressed against the upper surface of the stage main body 1, and in this state, the opening/closing valve on the work exhaust pipe 23 is opened, and the vacuum suction hole 21 for the work is opened. ) Is vacuumed, and the work W is vacuum-adsorbed. A little later than this timing, the 1st conveyance hand 63 releases the adsorption of the work W, releases the work W, and rises.

The first transfer hand 63 returns to the original standby position. In parallel, the exposure system 5 operates, and the work W is irradiated with light of a predetermined pattern to perform exposure. After exposure for a predetermined time, the second conveyance hand 64 is positioned above the work stage 4 and then descends a predetermined distance to adsorb the work W. The timing is slightly delayed from adsorption of the work W, the on-off valve on the work exhaust pipe 23 is closed, the air release valve is opened, and the work exhaust path 22 is opened to the atmosphere. Thereby, vacuum adsorption of the work W is released.

After that, the 2nd conveying hand 64 moves up to the upper part of the 2nd conveyer 62 after raising a predetermined distance. Then, the second conveying hand 64 descends a predetermined distance and, after placing the work W on the second conveying conveyor 62, releases the adsorption of the work W. The 2nd conveyer 62 carries the work W to the position for the next processing or operation of the work W. This operation is repeated, and the work W is exposed to light one by one.

In the exposure apparatus of the embodiment, as described above, the shrink sheet 3 prevents vacuum leakage during vacuum adsorption of the workpiece W, so that the vacuum adsorption does not cause errors, and the pattern is always projected to the correct position. Can be done. For this reason, the quality of the product is kept high.

The above-described embodiment was an exposure apparatus for a printed circuit board, but other exposure apparatuses may be similarly implemented as long as the object is a plate-shaped work W such as an exposure apparatus for a liquid crystal display. Further, examples of use of the work stage 4 other than the exposure apparatus include a substrate inspection apparatus, a silk printing apparatus, and a drilling apparatus.

In addition, in the case of employing the work stage 4 of the embodiment in the exposure apparatus, the average thickness of the shrinking sheet 3 contracted during vacuum adsorption of the work W is the depth of focus when the image is projected by the optical system. It is preferable to set it as 1/2 or less.

In the work stage of the embodiment, since the shrink sheet 3 is sandwiched between the stage main body 1 and the work W, in that portion, the shrink sheet 3 is in a state close to the optical system by the thickness of the shrink sheet 3. Therefore, if the thickness of the contracted shrink sheet 3 is thicker than 1/2 of the depth of focus, blurring of the image is likely to occur. The periphery of the work W with the shrink sheet 3 interposed therebetween is often an unused area (outside the area to which the pattern should be projected in the work W), but in the case of a use area, the exposure pattern is By blurring, it may cause product defects. Therefore, it is desirable to set it to 1/2 or less of the depth of focus.

1: Stage body 2: Exhaust system
21: vacuum suction hole for work 24: vacuum suction hole for sheet
3: shrink sheet 31: frame
4: work stage 5: exposure meter
6: Transfer system W: work

Claims (8)

As a work stage that holds a plate-shaped work,
A stage body having a vacuum suction hole for a workpiece on the workpiece holding surface, and
It is a work stage equipped with an exhaust system for adsorbing the work by vacuum suctioning the work vacuum suction hole when the work is in contact with the work at the holding position set on the work holding surface,
A shrink sheet is installed on the workpiece holding surface,
The shrinking sheet is a shape that surrounds the area outside the area where the vacuum suction hole for the work is installed, and is sandwiched between the work and the work holding surface of the stage main body when the work is in contact with the work holding surface at the holding position. It is a shape that extends along the periphery of the work,
The shrinking sheet has flexibility due to elasticity that contracts in the thickness direction when the work in contact with the work holding surface is vacuum-adsorbed and adheres to the work.
The shrink sheet is attached to the workpiece holding surface so as to be detachable,
The shrink sheet is installed in a state attached to the frame,
A work stage, wherein the frame holds the shrink sheet at a position outside the work when the work is in contact with the work holding surface and is vacuum-adsorbed. The method according to claim 1,
The work stage, wherein the shrink sheet has a shape overlapping with the work in the entire circumference of the periphery of the work in contact with the work holding surface at the holding position. The method according to claim 1,
The shrinking sheet has a shape having a region that does not partially overlap in a peripheral portion of the workpiece in contact with the workpiece holding surface at the holding position, and the length of the non-overlapping region in the circumferential direction is 10 mm or less. The method according to any one of claims 1 to 3,
A work stage, wherein the average thickness of the shrinking sheet contracted in the thickness direction when the work in contact with the work holding surface is vacuum-adsorbed is 0.5 mm or less. delete The method according to claim 1,
The stage main body has a flat surface outside a region in which the vacuum suction hole for work is provided, and the shrink sheet is provided on the flat surface. Light source,
An optical system that projects light from a light source as an image of a predetermined pattern,
It is equipped with the work stage according to any one of claims 1 to 3,
The exposure apparatus, wherein the holding position is a projection position of an image of a predetermined pattern by an optical system. The method of claim 7,
An exposure apparatus, wherein the average thickness of the contracted sheet contracted in the thickness direction when the work in contact with the work holding surface is vacuum-adsorbed is 1/2 or less of a depth of focus when the optical system projects the image.

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