JP6646556B2 - Contact exposure equipment - Google Patents

Description

  The invention of this application relates to a contact exposure apparatus that exposes a substrate by irradiating light through the mask while the mask is in close contact with the substrate.

  In photolithography for forming a fine structure on the surface of a substrate, there is an exposure step of exposing the substrate by irradiating light of a fine pattern, and an exposure apparatus is used. There are several different types of exposure equipment known, such as a projection exposure equipment that projects a mask image onto the surface of a substrate with a lens and exposes the light, and irradiates light through the mask with the mask in close contact with the substrate. A contact exposure apparatus that exposes a substrate by exposing the substrate is widely used.

JP-A-06-027674 JP-A-11-313635

A projection exposure apparatus that exposes a mask image by reducing the size of the image is used when a particularly fine circuit such as an LSI is formed, as typified by a stepper. On the other hand, contact exposure apparatuses have been often used for forming circuits that are not very fine, such as printed circuit boards.
Nevertheless, recently, there has been an increasing demand for performing exposure for forming a fine circuit of 100 μm or less by line and space (L / S) using a contact exposure apparatus. One reason for this is cost. Since the projection exposure apparatus requires a projection optical system including an imaging lens, it tends to be a very expensive system. On the other hand, the contact exposure apparatus requires an optical system for irradiating the parallel light, but is not as expensive as the optical system of the projection exposure apparatus, resulting in low apparatus cost. For these reasons, there has been an increasing demand for using a contact exposure apparatus even in forming finer circuits. For example, there is a demand to realize a fine circuit of about 10 to 50 μm in L / S by contact exposure.

In such a recent tendency to realize the formation of a fine circuit by a contact exposure method, which has been realized by a projection exposure apparatus, the presence of unevenness on the surface of a substrate has emerged as a new problem. As the functionality and complexity of products have increased, it has become increasingly necessary to manufacture circuit boards having complicated structures such as laminated boards and composite boards. For example, a structure in which another substrate is locally laminated on a substrate, a structure in which a flexible substrate is locally adhered on a rigid (hard) substrate, and the like are often used.
When contact exposure is performed on a substrate having unevenness on the surface as described above, the mask cannot adhere to the substrate in the concave portion. In this case, since the exposure is performed on the order of microns, there is a problem that an image is not formed due to light diffraction or diffusion at a position where the mask is as much as 100 μm above the substrate, and the pattern cannot be transferred.

  In order to solve this problem, Patent Literature 1 employs a flexible sheet-like mask (hereinafter, sometimes referred to as a flexible mask) as a mask, and pressurizes the mask with a fluid from the side opposite to the substrate. A configuration has been proposed in which the components are brought into close contact with each other. In this configuration, a more flexible sheet (hereinafter, referred to as a pressure sheet) is provided on the side opposite to the substrate with respect to the flexible mask. The pressure sheet forms a closed space like a balloon. The pressure sheet is brought into close contact with the mask, and in this state, the space inside the pressure sheet is filled with gas to expand the pressure sheet. The mask is expanded by the expanded pressure sheet, and the mask is brought into close contact with the substrate in this state. Hereinafter, this method is called a mask fluid pressurizing method.

According to the mask fluid pressurizing method, the mask can be in close contact with the substrate even in the concave portion, so that the pattern can be transferred. However, in the mask fluid pressurization method, the mask is inevitably expanded and contracted when the mask is brought into close contact with the substrate, so that the scale accuracy and the alignment accuracy of the pattern transferred to the substrate cannot be ensured.
That is, since the pressure sheet expands due to the filling of gas, it expands in a somewhat rounded shape. Therefore, the mask is also rounded and swells following the pressure sheet. On the other hand, although the surface has fine irregularities, the substrate is generally flat. When a rounded and swelled mask and pressure sheet are pressed against a flat substrate to bring them into close contact with each other, a contracted portion and a portion that is not so contracted are formed in the mask and pressure sheet. As a result, when the exposure is performed through the mask, the exposure is performed in a state where the scale of the pattern of the mask is different depending on the location, and the alignment accuracy (overlay accuracy) of the transferred pattern is reduced.

This problem was not so serious when a high alignment accuracy was not required, but became a serious problem in, for example, an exposure requiring an alignment accuracy of 30 μm / 500 mm or less.
In order to prevent expansion and contraction of the mask when pressed against the substrate, it is conceivable to attach the mask to a rigid support or use a rigid glass mask. Such a rigid mask cannot employ a mask fluid pressurizing method, and as a method for bringing the mask into close contact with each other, vacuum contact is used to evacuate a space between the mask and the substrate. However, even when a rigid mask is brought into close contact with the substrate by vacuum contact, the problem that the mask does not adhere to the substrate in the concave portion and an image is not formed due to light diffraction remains.

  Patent Document 2 discloses a technique in which a groove for air injection is provided on a stage on which a substrate is mounted, and air is injected from the groove to cause the substrate to float from a table and adhere to a mask. However, it is difficult to apply the technique of Patent Document 2 to substrates having different dimensions and / or shapes. That is, when the size and / or shape of the substrate is different, it is necessary to change the range of the air ejection, which is a very troublesome operation. Further, in Patent Literature 2, the space between the substrate and the mask is evacuated, but the air ejected from the stage easily enters the space between the substrate and the mask. In order to stabilize the vacuum evacuation, it is necessary to control the range and flow rate of air injection in accordance with the dimensions and shape of the substrate. Therefore, it is not a practical technology.

  The invention of this application has been made in order to solve the above-mentioned problem that appears when a finer pattern transfer is to be performed while adopting a contact method, and is a substrate having an uneven surface. It is another object of the present invention to provide a practical contact exposure apparatus which can perform exposure with a mask pattern and has excellent performance without a problem of pattern alignment accuracy deterioration.

In order to solve the above-mentioned problems, the invention according to claim 1 of the present application provides a state in which a mask and a substrate are in close contact with each other, and irradiates the substrate with light from a light source through the mask to thereby emit light of the mask pattern. A contact exposure apparatus that exposes
A table on which the substrate is placed,
A mask holder for holding a mask on the side opposite to the table with respect to the substrate,
A mask-side vacuum exhaust system that evacuates between the substrate mounted on the table and the mask held by the mask holder to bring them into close contact,
A table-side pressurizing mechanism that presses the substrate from the table side and makes it adhere to the mask,
The table side pressurizing mechanism includes a pressurizing sheet that covers the surface of the table, and a pressurizing air supply system that supplies gas through holes formed in the surface of the table,
The pressurizing sheet is provided in a state in which the periphery is sealed to the table, and when the gas is supplied by the pressurizing air supply system in a state where the substrate is placed, the pressurizing sheet expands toward the substrate and Has the flexibility of being able to press.
According to a second aspect of the present invention, in order to solve the above-mentioned problem, in the configuration of the first aspect, there is provided an extension means for extending the pressure sheet when the substrate is pressed. Having a configuration.
According to a third aspect of the present invention, in order to solve the above-mentioned problem, in the configuration of the second aspect, the stretching means includes a sheet-side vacuum exhaust system that vacuum-adsorbs the pressure sheet to the table. .
In order to solve the above problem, the invention according to claim 4 is the arrangement according to claim 3, wherein the pressure sheet has a hole in which the substrate is sucked by the sheet-side evacuation system to suck the substrate. It has a configuration of being provided.
According to a fifth aspect of the present invention, in order to solve the above problem, in the configuration of any one of the first to fourth aspects, the pressure sheet is provided in a state of being stretched on a frame, and the frame is It is configured to be detachable from the table.
According to a sixth aspect of the present invention, in order to solve the above problem, in the configuration of any one of the first to fifth aspects, a step for increasing the tension of the pressure sheet is covered with the pressure sheet of the table. In a portion that is provided.
In order to solve the above problem, the invention according to claim 7 is, in the structure according to any one of claims 1 to 6, provided with a controller that controls operations of the mask-side vacuum exhaust system and the pressurizing air supply system. The controller is configured to operate the pressurizing air supply system after operating the mask-side evacuation system.

As described below, according to the first aspect of the present invention, in addition to the substrate being brought into close contact with the mask by evacuation between the mask and the substrate, the substrate is brought into close contact with the mask by being pressed from the back pressure sheet. I do. For this reason, the adhesion between the substrate and the mask is further improved, and the pattern can be transferred to a substrate having irregularities. In addition, since a rigid mask such as a glass mask can be used, it is possible to prevent a decrease in alignment accuracy of a transferred pattern. Further, since the substrate is pressed from the side of the table to the mask by supplying air into the space formed by the pressurizing sheet, there is no need to particularly change the configuration even for substrates having different sizes and / or shapes. This is extremely simple and practical.
According to the second aspect of the present invention, in addition to the above-mentioned effects, since the stretching means for stretching the pressing sheet when pressing the substrate is provided, the unevenness due to the slack of the pressing sheet is reduced. The problem that the pattern is distorted due to the influence of the above is prevented.
According to the third aspect of the present invention, in addition to the above-described effects, since the stretching means is a means having a sheet-side vacuum exhaust system for vacuum-sucking the pressure sheet to the table, it is simpler than a mechanical structure. Become
According to the fourth aspect of the present invention, in addition to the above-described effects, the pressure sheet is provided with holes for sucking the substrate by being sucked by the sheet-side vacuum exhaust system, so that the sheet-side vacuum exhaust system is used. Then, the substrate is vacuum-sucked. For this reason, it is possible to prevent the substrate from shifting.
According to the fifth aspect of the present invention, in addition to the above effects, it is easy to replace the pressure sheet.
According to the sixth aspect of the invention, in addition to the above-described effects, the tension of the pressure sheet is increased, so that the problem that the wrinkles of the pressure sheet caused by loosening are transferred to the substrate can be more effectively prevented.
According to the seventh aspect of the invention, in addition to the above effects, the pressurizing air supply system operates after the mask-side vacuum exhaust system operates, so that air is formed and the vacuum by the mask-side vacuum exhaust system is reduced. The problem of insufficient exhaust does not occur.

It is a front section schematic diagram of a contact exposure apparatus of an embodiment. FIG. 2 is a schematic plan view of the table shown in FIG. 1. FIG. 4 is a schematic front sectional view of a main part showing an operation of the contact exposure apparatus.

Next, an embodiment (embodiment) for carrying out the invention of this application will be described. FIG. 1 is a schematic front view of the contact exposure apparatus of the embodiment.
The contact exposure apparatus shown in FIG. 1 includes a table 1, a transport system 2 for transporting a substrate S to be exposed and mounting the table 1, and a mask holder 3 for holding a mask M on which a pattern to be transferred is drawn. And an exposure system 4 for irradiating the substrate S with light through the mask M.
Although not shown in detail, the exposure system 4 includes a light source 41 and an optical system 42 that irradiates the mask M with light from the light source 41 as parallel light. The optical system 42 includes a collimator lens.

  The table 1 is a member for holding the substrate S at a predetermined position where light is irradiated by the exposure system 4. The predetermined position is, for example, a position where the substrate S is located on the focal plane of the optical system 42. The table 1 is provided with a table drive mechanism 11. The table drive mechanism 11 is a mechanism that adjusts the position of the table 1 by moving the table 1 in two directions orthogonal to each other and a rotation direction (XYθ direction). The XY directions are directions orthogonal to each other in a horizontal plane, and the θ direction is a direction rotating about a rotation axis perpendicular to the horizontal. In addition, a function of adjusting the position by moving in the Z direction (vertical direction with respect to the horizontal direction) may be added.

  The mask holder 3 is a frame-shaped member. In this embodiment, the mask M is rigid and made of glass such as blue plate glass. However, a flexible sheet-shaped mask M may be used. For example, a thin sheet made of PET (polyethylene terephthalate) formed with a pattern may be used in a state of being stretched on a holder. The mask M is provided with a mask driving mechanism 31. The mask driving mechanism 31 is a mechanism for adjusting the position by moving the mask M in the X and Y directions and adjusting the position by moving the mask M in the Z direction. When the mask M is flexible, the mask M is supported by a transparent support as described later.

  A camera (not shown) is provided above the mask M. Alignment marks are provided on the mask M and the substrate S. Each alignment mark is photographed by a camera, and the table 1 is moved by the table driving mechanism 11, the mask M is moved by the mask driving mechanism 31, or Both positions the substrate S and the mask M.

  The transport system 2 may employ various configurations. In this embodiment, the transport system 2 includes a conveyor 21 and a transfer hand 22. Conveyors 21 are provided on the carry-in side and carry-out side with respect to the table 1, and a transfer hand 22 is provided for moving the substrate S between each conveyor 21 and the table 1. The transfer hand 22 moves the substrate S while vacuum-sucking the substrate S with the suction pad 221 at the lower end.

  Such a contact exposure apparatus includes a mask-side vacuum evacuation system 5 and a table side so that the mask M and the substrate S are brought into close contact with each other, and the mask M is brought into close contact even with the substrate S having an uneven surface. And a pressure mechanism 6. The table-side pressing mechanism 6 includes a pressing sheet 61 and a pressurizing air supply system 62 that supplies air behind the pressing sheet 61 (on the side opposite to the mask M) to increase the pressure. Hereinafter, these will be described in detail with reference to FIGS. FIG. 2 is a schematic plan view of the table 1 shown in FIG.

First, a vacuum seal 7 is attached to the table 1 as shown in FIG. In this embodiment, the vacuum seal 7 is a tubular (ie, hollow) member. More specifically, the vacuum seal 7 is a tube made of silicone rubber, and is fixed to the surface of the table 1 by adhesion. As shown in FIG. 2, the vacuum seal 7 is endless, and in this example, has a square shape. The substrate mounting area is set inside the vacuum seal 7.
As shown in FIG. 1, the vacuum seal 7 is provided with a seal supply / discharge system 71 for supplying / discharging the internal space. The seal supply / discharge system 71 is a gas supply / discharge system for supplying air into the vacuum seal 7 to expand the vacuum seal 7 or exhausting the inside to contract the vacuum seal 7.

  The table 1 has a vacuum exhaust hole 12 for evacuating the space between the mask M and the substrate S to a vacuum. The evacuation hole 12 is located slightly inside the vacuum seal 7. The mask-side evacuation system 5 is connected to the evacuation hole 12. When the mask M is positioned at a predetermined position close to the table 1 with the vacuum seal 7 expanded by the seal supply / discharge system 71, the mask M slightly crushes the vacuum seal 7. As a result, the space inside the vacuum seal 7 is sealed, and when the mask-side evacuation system 5 operates in this state, the space inside the vacuum seal 7 is evacuated to a vacuum. In this space, since the mask M and the substrate S face each other, the space between the mask M and the substrate S is evacuated to a vacuum.

On the other hand, the table 1 is provided with a pressurized air supply hole 13 separately from the vacuum exhaust hole 12. As shown in FIG. 2, the pressurizing air supply hole 13 is formed at the center of the table 1. As shown in FIG. 2, an air supply groove 14 is formed on the surface of the table 1. The air supply groove 14 has a right-angle lattice shape in this example. The air supply groove 14 communicates with the pressurized air supply hole 13.
A pressure sheet 61 is attached to the table 1 so as to cover the air supply holes 13 and the air supply grooves 14. The pressure sheet 61 is a flexible sheet, for example, a resin sheet such as PET. As described later, the pressure sheet 61 has flexibility that can swell toward the substrate S and press the substrate S. When a sheet made of resin such as PET is used as the pressure sheet 61, the thickness may be about 100 to 200 μm.

As shown in FIG. 2, the pressure sheet 61 is generally rectangular. The pressure sheet 61 is provided so as to be stretched on the sheet frame 611, and the sheet frame 611 is fixed to the table 1. The seat frame 611 is fixed to the table 1 by a detachable structure such as screwing. Therefore, the pressure sheet 61 is detachable from the table 1.
In addition, as shown in FIGS. 1 and 2, the sheet frame 611 has a smaller size than the vacuum seal 7. The fixing position of the seat frame 611 is a position inside the vacuum exhaust hole 12.

Further, as shown in FIG. 1, the table 1 has a step 15, and has a cross section that is thick at a central portion and thin at a peripheral portion. The substrate mounting area is set on a thick central surface. The sheet frame 611 is fixed at a thin peripheral portion, and thus the pressure sheet 61 covers the surface of the table 1 including the step 15.
As shown in FIG. 1, a pressurized air supply system 62 is connected to the pressurized air supply hole 13. The pressurized air supply system 62 is a system that supplies compressed air such as dry air in this embodiment. The pressurizing air supply system 62 includes a pressure adjusting valve (not shown) for adjusting the air supply pressure.

  The pressure sheet 61 presses the substrate S toward the mask M at the time of exposure to improve the adhesiveness between the substrate S and the mask M. An extension means is provided for bringing the pressure sheet 61 into an extended state when performing. Hereinafter, this point will be described.

  The pressure sheet 61 according to the embodiment is flexible as described above, and unevenness is likely to be formed in a non-stretched state, that is, in a loose state. When the substrate S is pressed in a state where irregularities are formed, if the substrate S is flexible, irregularities also occur on the substrate S, and as a result, pattern transfer is likely to be distorted. In addition, when the substrate S is placed on the press sheet 61 in a state where the substrate S is loosened and uneven, the substrate S is likely to be displaced due to bounce. The displacement is corrected at the time of alignment, but if the amount of displacement is large, it may exceed the range that can be corrected by alignment. In consideration of these points, the device of the embodiment is provided with the extension means.

  In this embodiment, a means for vacuum-sucking the pressure sheet 61 to the table 1 is employed as the stretching means. Specifically, the stretching means is a system 8 that also uses the pressurized air supply hole 13 as the vacuum exhaust hole 12, and evacuates the air through the pressurized air supply hole 13, thereby extending the pressurized sheet 61. ing. Hereinafter, the evacuation system 8 is referred to as a seat-side evacuation system.

  As shown in FIG. 1, a switching valve 132 is provided in a pipe 131 communicating with the air supply hole 13 for pressurization. The pressurizing air supply system 62 and the seat-side evacuation system 8 are provided in parallel with the switching valve 132, and the switching valve 132 communicates the pressurizing air supply hole 13 with the piping of the pressurizing air supply system 62. And a position (hereinafter referred to as an air supply position) for shutting off the piping of the seat-side evacuation system 8, the air supply hole 13 for pressurizing is cut off for the piping of the air supply system 62 for the pressurization, and the seat-side evacuation system 8 (hereinafter referred to as an exhaust position). When the sheet-side evacuation system 8 is operated with the switching valve 132 at the evacuation position, the pressurized sheet 61 is vacuum-adsorbed to the table 1 and is in an extended state. In some cases, the pressure sheet 61 slightly protrudes into the air supply groove 14, but on the surface of the table 1 other than the air supply groove 14, the pressure sheet 61 is in an expanded state.

Further, in this embodiment, there is provided a means for vacuum-sucking the substrate S when the substrate S is placed on the table 1 so that there is no displacement. However, as described above, the surface of the table 1 is covered with the pressure sheet 61, and the substrate S is placed on the pressure sheet 61. Therefore, a normal vacuum suction configuration cannot cope with the problem. Cost.
In this embodiment, while the pressure sheet 61 is provided between the substrate S and the table 1, holes 610 are formed in the pressure sheet 61 as shown enlarged in FIG. Is adopted. The pressurizing sheet 61 expands like a balloon when it is supplied with air, and presses the substrate S. Therefore, the pressurizing sheet 61 has essentially no holes. Contradicts. However, from the viewpoint of the inventor, even when the hole 610 is opened, the function of the pressure sheet 61 is not impaired because the substrate S closes the hole 610 when pressing the substrate S. With such an eye, the inventor has come up with a structure in which a hole (hereinafter, referred to as a sheet hole) 610 is opened in the pressure sheet 61 to enable vacuum suction of the substrate S.

  About two to four sheet holes 610 are provided. It is desirable that the position of the sheet hole 610 be symmetrical with respect to the center of the substrate mounting area. FIG. 2 shows an example in which two sheet holes 610 are provided. It is desirable that the position where the sheet hole 610 is provided is a position that is not far away from the pressurizing air supply hole 13 or the air supply groove 14. When the sheet hole 610 is provided at a position far away from the pressurizing air supply hole 13 and the air supply groove 14, when the pressurizing sheet 61 is in close contact with the table 1 at a position therebetween, the sheet hole 610 is evacuated to the sheet side. This is because the substrate S is not communicated with the system 8 and the substrate S is not vacuum-sucked. Therefore, it is desirable that the sheet hole 610 is provided at a position facing the air supply hole 13 for pressurization or the air supply groove 14 or at a position in the vicinity thereof. It is more desirable that the center of the sheet hole 610 is located at the pressurizing intake hole 13 or the supply groove 14.

  The apparatus includes a controller (not shown) that controls each unit. A sequence program is mounted on the controller, and each part is programmed to operate in a predetermined sequence.

Next, the operation of such a contact exposure apparatus will be described with reference to FIGS. FIG. 3 is a schematic partial sectional view showing the operation of the contact exposure apparatus.
First, the table 1 is located at a predetermined standby position. The substrate S is transported by the transport system 2 and is placed on the table 1 as shown in FIG. At this time, the switching valve 132 is in the exhaust position, and the pressurized sheet 61 is vacuum-adsorbed to the table 1 in advance by the seat-side evacuation system 8. Therefore, the placed substrate S is vacuum-sucked by evacuation through the sheet holes 610. At this time, when the substrate S is vacuum-adsorbed by evacuation through the sheet hole 610, the sheet hole 610 is closed by the substrate S as a result. When mounting the substrate S, the vacuum suction by the sheet-side evacuation system 8 may be temporarily reduced or stopped in order to stabilize the mounting operation.

Next, a mark of the substrate S is photographed by a camera (not shown), and alignment of the substrate S is performed based on the result. That is, the table driving mechanism 11 operates to move the table 1 in the XYθ directions, and to position the substrate S at a predetermined position.
Next, the table driving mechanism 11 operates to raise the table 1 by a predetermined distance. As a result, the vacuum seal 7 on the table 1 comes into contact with the mask M as shown in FIG. The vacuum seal 7 is in a state of being expanded by being supplied with air by a seal supply / discharge system 71 in advance.
In this state, the mask-side evacuation system 5 operates, and the space between the mask M and the substrate S is evacuated. As a result, the mask M and the substrate S are brought into close vacuum contact. The vacuum seal 7 is slightly collapsed by the evacuation.

Next, the switching valve 132 operates to switch from the exhaust position to the air supply position. Then, the pressurizing air supply system 62 operates, and gas flows in through the pressurizing air supply hole 13. As a result, the pressure in the space below the pressure sheet 61 (the space between the pressure sheet 61 and the surface of the table 1) increases, and the pressure sheet 61 expands as shown in FIG. Thereby, the pressure sheet 61 presses the substrate S, and the adhesion between the substrate S and the mask M is further improved. At this time, since the sheet holes 610 of the pressure sheet 61 are closed by the substrate S that is in close contact, the high-pressure gas in the pressure sheet 61 does not leak out, and the pressure between the pressure sheet 61 and the table 1 is reduced. The space has a sufficient positive pressure to press the substrate S.
Since the pressing of the substrate S by the pressurizing air supply system 62 acts to push up the substrate S and the mask M as a whole, the mask M shifts slightly upward and the vacuum seal 7 slightly expands from the collapsed state. There can be.

In this manner, the substrate S comes into close contact with the mask M by the negative pressure of the vacuum exhaust on the mask M side and by the pressing by the expanding pressure sheet 61 on the table 1 side, and the substrate S comes into contact with the mask M with higher adhesion. In close contact. In this state, a camera (not shown) photographs the mark on the substrate S and the mark on the mask M as necessary, and alignment is performed again.
Then, the exposure system 4 operates in a state where the substrate S and the mask M are located at predetermined positions, and the light from the light source 41 is applied to the substrate S via the mask M to perform exposure. After the exposure for a predetermined time, the operation of the exposure system 4 stops.

Thereafter, the operation proceeds to the unloading operation of the substrate S. First, the operations of the mask-side evacuation system 5 and the pressurized air supply system 62 are stopped. Then, the seal supply / discharge system 71 operates, and the inside of the vacuum seal 7 is evacuated to a vacuum. Thereby, the vacuum seal 7 is compressed and the sealing is released. As a result, the space between the mask M and the substrate S is opened to the atmosphere, and the pressure in this space returns to the atmospheric pressure.
Next, the switching valve 132 is changed from the air supply position to the exhaust position, the sheet-side evacuation system 8 is operated, and the pressure sheet 61 and the substrate S are vacuum-adsorbed to the table 1. In this state, the table driving mechanism 11 operates to lower the table 1 by a predetermined distance. As a result, the table 1 returns to the standby position. Then, the operation of the seat side evacuation system 8 is stopped, a vent valve (not shown) is opened, and the piping communicating with the pressurizing air supply hole 13 returns to the atmospheric pressure.

In this state, the transport system 2 operates, and the transfer hand 22 on the unloading side picks up the substrate S and transfers it to the conveyor 21, and the conveyor 21 unloads the substrate S out of the apparatus. Then, with the switching valve 132 in the exhaust position, the seal-side evacuation system is operated, and the pressure sheet 61 is vacuum-adsorbed to the table 1. In this state, the next substrate S is carried in by the transport system 2, and the same processing is repeated. The above sequence is realized by a sequence program mounted on the controller.
While the above operation is repeated, the pressure sheet 61 repeatedly expands and contracts, so that it may be worn. In this case, the pressure sheet 61 is removed and replaced together with the sheet frame 611.

According to the contact exposure apparatus of the embodiment according to the above configuration and operation, in addition to the substrate S being in close contact with the mask M by vacuum evacuation between the mask M and the substrate S, the substrate S is pressed by the pressure sheet 61 behind. Adhere to the mask M. Therefore, the adhesion between the substrate S and the mask M is further improved, and the pattern can be transferred to the substrate S having irregularities.
Further, since a rigid mask M such as a glass mask M can be used, there is no problem of expansion and contraction of the image of the mask M, and the scale accuracy of the transferred pattern is reduced and the accuracy of the transfer position is reduced. No problem.
Further, since the pressing of the substrate S against the mask M from the side of the table 1 is performed by supplying air into the space formed by the pressing sheet 61, the substrate S having a different size and / or shape is particularly used. There is no need to change the configuration, which is extremely simple. That is, it is only necessary to provide the pressure sheet 61 large enough to cover the substrate S having the largest dimension.

  In the operation of the contact exposure apparatus of the above embodiment, when the substrate S is loaded, the mask-side vacuum exhaust system 5 is first operated to vacuum-adsorb the mask M and the substrate S, and then the pressurizing air supply system 62 is operated. The dots have a special meaning. If the pressurized air supply system 62 is operated at the same time as the mask-side vacuum exhaust system 5 or the pressurized air supply system 62 is operated and the mask-side vacuum exhaust system 5 is operated later, the gap between the substrate S and the mask M is reduced. Vacuum adhesion may be insufficient. That is, when the pressurizing sheet 61 expands due to the operation of the pressurizing air supply system 62 and the substrate S is pressed by the pressurizing sheet 61 and comes into contact with the mask M, if the contact is circumferential, air accumulates inside thereof. It can happen. In this case, even if the inside air reservoir is exhausted by the mask-side evacuation system 5, it is not sufficiently exhausted and may remain. When this occurs, the function of the mask-side evacuation system 5 is not sufficiently exhibited, and the adhesion between the substrate S and the mask M tends to be insufficient. Therefore, it is desirable to operate the pressurized gas supply system 62 after the substrate S and the mask M are brought into close contact with each other by operating the mask-side evacuation system 5.

Before the pressurizing air supply system 62 is operated, the substrate S is sucked by the sheet-side evacuation system 8 through the sheet holes 610 on the pressurizing sheet 61 side and by the mask-side evacuation system 5 on the mask M side. ing. It is preferable that both the vacuum suctions have the same level of force.
In the above embodiment, the substrate S may be a flexible sheet made of PET or a rigid sheet made of epoxy resin (for example, glass fiber reinforced epoxy resin).

  Although the mask M is a rigid one such as a glass mask, the mask M can be implemented even with a flexible mask. When the mask M is flexible, a support transparent to light having an exposure wavelength is used. The support supports the mask on the side opposite to the substrate, and prevents the mask from being deformed when the mask is pressed against the substrate S.

Although the sheet-side evacuation system 8 is used as a means for extending the pressure sheet 61, other configurations are also possible. For example, a configuration in which the pressure sheet 61 is mechanically pulled and extended may be employed. Specifically, a mechanism may be employed in which the end of the pressure sheet 61 is fixed to a shaft connected to the torque motor, and a force is applied in a direction in which the pressure sheet 61 is wound up to pull the pressure sheet 61 to eliminate slack. However, in comparison with this, the configuration using the sheet-side evacuation system 62 is more preferable because the configuration is simplified.
Further, when a configuration in which the pressurizing sheet 61 is extended by vacuum suction is employed, an exhaust system different from the pressurizing air supply system 62 may be employed. In this case, a vacuum evacuation system is provided separately from the pressurized air supply holes 13, and a sequence program is programmed to operate by switching.

  When the pressure sheet 61 is extended, the step 15 provided on the surface of the table 1 has an important meaning. The present invention can be implemented even if the surface of the table 1 is a flat surface having no step 15 or a surface having only a gentle curved surface. However, when the step 15 is formed as in the embodiment, the tension is increased because the pressing sheet 61 is caught at the corner. That is, the step 15 provided on the surface of the table 1 makes it easier to stretch the pressure sheet 61, and more effectively prevents the problem that the wrinkles of the pressure sheet 61 caused by loosening are transferred to the substrate S. Having. Even if the shape is not the step 15, a shape having similar corner portions is sufficient, and the same effect can be obtained by using a protrusion or other shapes.

  The configuration in which the substrate S is sucked by vacuum suction through the sheet holes 610 has a meaning of preventing the displacement of the substrate S when superimposed on the mask M, but is not essential. For example, since the frictional force between the pressure sheet 61 and the substrate S is sufficient and the substrate S does not shift on the pressure sheet 61 even when the table 1 is moved by the table driving mechanism 11 for alignment. If so, vacuum suction is unnecessary. When the substrate S is not vacuum-sucked, the sheet hole 610 is not provided.

REFERENCE SIGNS LIST 1 table 11 table drive mechanism 12 vacuum exhaust hole 13 pressurized air supply hole 132 switching valve 14 air supply groove 2 transfer system 21 conveyor 21 transfer hand 221 suction pad 3 mask holder 31 mask drive mechanism 4 exposure system 41 light source 42 optical system 5 mask Side vacuum exhaust system 6 table side pressurizing mechanism 61 pressurized sheet 610 sheet hole 611 sheet frame 62 pressurized air supply system 7 vacuum seal 71 seal supply and discharge system 8 sheet side vacuum exhaust system

Claims (7)

A contact exposure apparatus that exposes the pattern of the mask to the substrate by irradiating the substrate with the light from a light source through the mask in a state where the mask and the substrate are in close contact with each other,
A table on which the substrate is placed,
A mask holder for holding a mask on the side opposite to the table with respect to the substrate,
A mask-side evacuation system that evacuates the substrate placed on the table and the mask held by the mask holder to bring them into close contact,
A table-side pressing mechanism that presses the substrate from the table side and makes it adhere to the mask,
The table-side pressurizing mechanism includes a pressurizing sheet that covers the surface of the table, and a pressurizing air supply system that supplies gas through holes formed in the surface of the table,
The pressurizing sheet is provided in a state where the periphery is sealed to the table, and when the gas is supplied by the pressurizing air supply system in a state where the substrate is placed, the pressurizing sheet expands toward the substrate. A contact exposure apparatus having flexibility capable of pressing a contact.   2. The contact exposure apparatus according to claim 1, further comprising: an extension unit configured to extend the pressure sheet when the substrate is pressed.   3. The contact exposure apparatus according to claim 2, wherein the extension unit includes a sheet-side evacuation system that vacuum-adsorbs the pressure sheet to the table.   4. The contact exposure apparatus according to claim 3, wherein the pressure sheet is provided with a hole that is sucked by the sheet-side evacuation system to suck the substrate.   5. The contact exposure apparatus according to claim 1, wherein the pressing sheet is provided in a state of being stretched on a frame, and the frame is detachable from the table. 6.   6. The contact exposure apparatus according to claim 1, wherein a step for increasing the tension of the pressure sheet is provided in a portion of the table covered by the pressure sheet.   A controller is provided for controlling the operations of the mask-side evacuation system and the pressurized air supply system, and the controller operates the pressurized air supply system after operating the mask-side evacuation system. 7. A contact exposure apparatus according to claim 1, wherein:

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