JP4651648B2 - Contact exposure method and apparatus - Google Patents

Description

  The present invention relates to an adhesion method and an exposure apparatus for closely contacting a photosensitive substrate and a film on which a pattern is formed when exposing the photosensitive substrate with an exposure apparatus, and in particular, the adhesion is optimal. The present invention relates to a method and an exposure apparatus.

  When manufacturing a printed circuit board, an exposure apparatus is used in which an original film on which a circuit pattern is formed is brought into close contact with a photosensitive substrate and exposed to expose the circuit pattern on the substrate.

  Various methods are known for bringing the original film into close contact with the photosensitive substrate. Among these, the vacuum contact method is such that the opposing edge portions of the original film and the substrate having photosensitivity are brought into close contact with each other through packing, and then the airtight space formed thereby is evacuated by a vacuum pump or the like. That is, the original film and the photosensitive substrate are brought into close contact with each other.

  However, in the above-described method, when the original film and the photosensitive substrate are brought into close contact with each other, if the distance between them is reduced, the close contact can be made with high precision. There is a possibility that the air will be in close contact and the air in the center will not escape, resulting in poor contact.

  In view of this, a close contact apparatus with a small contact error and good air escape, as shown in Patent Document 1, has been proposed. In the contact device described in Patent Document 1, in addition to being able to arrange the substrate and the original film at a narrow interval, two airtight chambers are provided and pressure is reduced simultaneously, thereby achieving high contact accuracy and prevention of contact failure.

In addition to the method described in Patent Document 1, a device described in Patent Document 2 that improves the adhesion accuracy by removing warpage and wrinkles of a film-like substrate has also been proposed.
JP 7-219234 A JP 2001-209192 A

  However, in the apparatus of Patent Document 1, the edge portion of the original film is formed so that an airtight chamber is formed between the two instead of directly attaching and supporting the light transmissive plate and the original film. Only it is attached to a light-transmitting plate and carried. For this reason, there is a possibility that the original film is bent or the bonded part is peeled off while repeating the exposure process, and there is a possibility that the quality of the product may vary, especially when a large amount of the product is produced. In addition, since the apparatus described in Patent Document 2 has a structure in which a film-like substrate is sandwiched from above and below and vacuum is evacuated after confirming alignment, it takes time to confirm alignment and completely prevents poor adhesion. It was difficult to do.

  Therefore, it has become necessary to develop an adhesion method that suppresses an adhesion error while securing the quality of a product even in mass production by directly attaching an original film to a light-transmitting plate.

  As described above, the vacuum adhesion method is employed as a method of attaching an original film to a light-transmitting plate and making it adhere to a photosensitive substrate. Accordingly, a method and an exposure apparatus for effectively preventing the adhesion failure by effectively evacuating the central portion while suppressing an adhesion error when the original film and the substrate having photosensitivity are evacuated. It is hoped to provide.

  Accordingly, the present invention provides a method and an exposure apparatus that further improve the process of the vacuum contact method.

  More specifically, the following is provided.

(1) A vacuum contact exposure method,
A step of bringing the packing into close contact with a mask disposed on the table by packing provided on an edge of the table on which the workpiece is placed;
Evacuating to an initial set pressure value, bending the mask in a convex shape, and closely contacting the work from the approximate center of the mask;
A step of further evacuating and raising a mask holder for holding the edge of the mask, increasing the deflection of the mask, and further contacting the workpiece toward the edge of the mask; and A step of stopping the lift of the mask holder in response to close contact with the substantially edge portion of the workpiece,
The vacuum contact exposure method comprising:

  According to the invention of (1), the packing is first brought into close contact with the mask and evacuated to the initial set pressure value, so that the mask is bent into a convex shape and is brought into close contact with the workpiece from the approximate center of the mask. Let Normally, when the vacuum is further evacuated, the mask is subjected to a downward pulling force, and the edge of the mask is in close contact with the work, and the vacuum at the approximate center of the mask may not be sufficiently evacuated.

  Therefore, by raising the mask holder that holds the edge of the mask together with evacuation and increasing the deflection of the mask, it is possible to make the mask more closely contact the workpiece from the approximate center of the mask toward the edge. become.

  Further, by stopping the rising of the mask holder in response to the mask being brought into close contact with the substantially edge portion of the workpiece, a contact error due to deformation of the mask or the like can be suppressed.

  Here, the workpiece is a substrate having photosensitivity, and a circuit pattern formed on the original film is transferred by exposure.

  Here, the table is a device that carries the workpiece, and includes a vacuum piping system for evacuating and a packing for forming an airtight chamber in close contact with a mask holder described later. In addition, the table can be rotated in addition to moving in the vertical and horizontal directions in order to control the position of the workpiece and the mask holder.

  Here, the packing is used to form an airtight chamber in close contact with the mask holder, and any material such as rubber, plastic, or silicon may be used as long as confidentiality can be maintained. Further, it may be a plastic material that can expand to adhere to the mask. In this case, the method of expanding the packing may be any method such as gas supply or hydraulic pressure, but is preferably gas supply. As will be described later, the gas can be supplied by a method well known in the art such as an air supply system using a gas supply source, a regulator, a solenoid valve, and the like.

  Here, the mask is a member carrying an original film in which a circuit pattern is formed on a material such as glass or acrylic. The mask and the workpiece can have a reference mark for positioning at the time of close contact.

  Here, the mask holder is a member for carrying the mask, and can further have a mechanism that can move up and down. An example of the mechanism is a cylinder, but other mechanisms well known to those skilled in the art, such as a method using a gear, can also be used.

  Here, the equipment for evacuating may be any evacuating apparatus composed of a vacuum pump and a vacuum pressure control regulator.

  (2) A vacuum contact exposure method in which the raising of the mask holder is controlled by a cylinder mounted on the mask holder.

  According to the invention of (2), the mask holder is equipped with a cylinder, and the amount of deflection of the mask is adjusted by moving the mask holder up and down by the cylinder. Here, in order to drive the cylinder, any power source such as gas, hydraulic pressure, electric motor or the like can be used.

  (3) A vacuum contact exposure method in which, after the center of the mask comes into contact with the workpiece, the ascending force of the mask holder is suppressed and the vacuum pulling pressure is controlled to be maintained higher than the ascending force of the mask holder.

  According to the invention of (3), after the center of the mask comes into contact with the workpiece, the ascending force of the mask holder is suppressed and the evacuation pressure is controlled to be maintained higher than the ascending force of the mask holder. Accordingly, the mask and the work can be prevented from closely contacting each other from the substantially center toward the edge portion, and air can be prevented from remaining at the substantially center, thereby suppressing an adhesion error.

  (4) A vacuum contact exposure method in which the cylinder is lifted by supplying gas.

  As described above, in order to drive the cylinder, any power source such as gas, hydraulic pressure, electric motor, etc. can be used, but it is necessary to perform delicate control when driving the cylinder. From the above, it is preferable to use gas.

  Here, although air, nitrogen, etc. can be utilized for gas, it is preferable to use air from an economical viewpoint and availability. When the cylinder is driven by gas supply, it can be realized by further providing a gas supply source for supplying gas, a regulator (regulator) for controlling the gas flow rate, and an electromagnetic valve.

  As the gas supply source, any gas accumulator that compresses and accumulates gas in advance and discharges it as necessary can be used. Moreover, you may use an air supply apparatus well known in the art such as any air supply pump without using an air accumulator.

  Regulators (regulators) and solenoid valves can be used of any type that controls the flow rate of gas from the source.

(5) First, only vacuuming is performed, and in response to the vacuum pressure resulting from the vacuuming reaching the first set value, the air pressure reaches the first set value,
Subsequently, evacuation and air supply are performed, and in response to the vacuum pressure reaching the second set value, the air pressure reaches the second set value,
After the air pressure reaches the second set value, stop air supply, release the air pressure,
Continue evacuation until the vacuum pressure reaches the third set value,
A vacuum contact exposure method characterized by controlling the vacuum pressure and the feed pressure as described above.

  According to the invention of (5), the respective steps of the invention of (1) can be realized by controlling the vacuum pressure and the air supply pressure.

  Here, control until each set value is reached is performed based on a time parameter. The time until each set value is reached may be determined based on the performance of the evacuation system and the air supply system, or may be arbitrarily set as long as it is within the performance range. Regarding a method for controlling the air supply system so that only the vacuuming is performed first and the air supply pressure reaches the first set value promptly from zero at the same time that the vacuum pressure by the vacuum reaches the first set value. This will be described later.

  According to the present invention, it is possible to provide a vacuum contact exposure method with less contact error and preventing contact failure.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an example of a functional configuration diagram of a vacuum contact exposure apparatus using the vacuum contact exposure method of the present invention. FIG. 2 is an example of a functional configuration diagram of a control unit of a vacuum contact exposure apparatus using the vacuum contact exposure method of the present invention. FIG. 3 is an example of a flowchart showing a contact process in the vacuum contact exposure method of the present invention. FIG. 4 is a graph showing an example of pressure control in the vacuum contact process of the present invention. FIG. 5 is a graph showing measurement data of the vacuum pressure in the example according to the present invention. FIG. 6 is a schematic view of vacuum contact according to the present invention. FIG. 7 is a graph showing vacuum pressure measurement data when a mask upper / lower cylinder is not used as a comparative example. FIG. 8 is a schematic diagram of vacuum contact in a comparative example.

  FIG. 1 is an example of a functional configuration diagram of a vacuum contact exposure apparatus using the vacuum contact exposure method of the present invention. The vacuum contact exposure apparatus 100 includes a mask 110, a workpiece 120, a packing 130, a table 140, a vacuum piping system 150, a vacuum regulator 155, a vacuum pump 157, a mask upper and lower cylinder 160, a mask holder 170, a solenoid valve 180, a regulator 185, and a gas. A supply source 187 and a control unit 190 are included. In FIG. 1, the mask 110 and the workpiece 170 are arranged in a vertical relationship, but the arrangement is arranged upside down, arranged vertically, evacuated from the horizontal direction, and operated the mask holder. Such modifications can be performed by appropriately rearranging other components. Here, it describes about the example arrange | positioned up and down.

  The mask 110 is a light transmissive member having an original film on which a circuit pattern is formed.

  The work 120 is a substrate having photosensitivity, and a circuit pattern formed on the original film is transferred by exposure.

  As described above, the packing 130 may be any material as long as it can maintain airtightness. However, when an expandable material is used, the packing 130 expands by air supply and adheres to the mask 110 or the mask holder 170. Constitutes an airtight chamber. The air supply to the packing 130 may be supplied from a gas supply source 187 described later or may be supplied from a separate gas supply source. In addition, the control of air supply may be shared by a regulator 185 and a solenoid valve 180 which will be described later, or may be realized by another control system or the like (not shown). Moreover, when the packing which consists of a non-expandable raw material is employ | adopted, a packing and a mask or a mask holder can contact | adhere by dropping a mask holder.

  The table 140 is a device that carries the workpiece 120, and includes a packing 130 that is in close contact with the vacuum piping system 150 and the mask holder 170 for evacuating and forms an airtight chamber. Further, the table can be moved and rotated in the vertical and horizontal directions so that the respective reference marks are aligned in order to control the positioning of the workpiece 120 and the mask 110. That is, it can move in the X, Y, and θ directions.

  The vacuum piping system 150 evacuates the hermetic chamber together with the vacuum regulator 100 and the vacuum pump 100.

  The vacuum regulator 155 adjusts the vacuuming pressure in accordance with a command from the control unit 190.

  The vacuum pump 157 supplies a negative pressure for evacuating the airtight chamber.

  The mask up / down cylinder 160 is mounted on the mask holder 170 and moves the mask holder 170 up and down.

  The mask holder 170 carries the mask 110 and is moved up and down by the mask upper and lower cylinders.

  The electromagnetic valve 180 is controlled by the regulator 185 and opens and closes to supply gas.

  The regulator 185 adjusts air supply according to a command from the control unit 190.

  The gas supply source 187 supplies a gas for operating the mask upper / lower cylinder 100.

  The controller 190 controls the vacuum regulator 155 and the regulator 185.

  FIG. 2 is an example of a functional configuration diagram of the control unit 190 of the vacuum contact exposure apparatus using the vacuum contact exposure method of the present invention.

  The control unit includes an air supply system adjustment unit 210, a control unit 220, a vacuum system adjustment unit 230, and a storage unit 240.

  The air supply system adjustment means 210 is connected to the regulator 285, monitors the pressure of the air supply system, outputs it to the control device 220, and outputs an air supply pressure control command from the control means 220 to the regulator 285.

  The control means 220 receives pressure information from the air supply system adjustment means 210 and the vacuum gauge adjustment means 230, and reads a program stored in the storage means 240, thereby sending a pressure adjustment command to the air supply system adjustment means 210 and the vacuum. Output to the meter adjusting means 230. The control means 220 can be composed of an existing arithmetic device such as a CPU.

  The vacuum system adjusting means 230 is connected to the vacuum regulator 255, monitors the pressure of the vacuum system, outputs it to the control means 220, and outputs a vacuum pressure control command from the control means 220 to the vacuum regulator 255.

  The storage unit 240 stores a series of programs for realizing the vacuum contact exposure method according to the present invention. In addition, the storage unit 240 can store data relating to air supply and evacuation in a series of processes so that the data can be referred to later. The storage unit 240 can use any storage medium such as a hard disk, a semiconductor storage element, or a portable storage medium.

  FIG. 3 is an example of a flowchart showing a contact process in the vacuum contact exposure method of the present invention.

  In the contact process in the vacuum contact exposure method according to the present invention, first, in step S305, the control unit 190 determines alignment between a reference mark (not shown) for alignment between the mask 110 and the workpiece 120, and If there is a match, the process proceeds to step S310. If matching is not achieved, the process proceeds to step S303.

  In step S303, the control unit 190 moves or turns the table 140 in the vertical and horizontal directions so that the reference marks on the mask 110 and the workpiece 120 are aligned, and the process proceeds to step S305.

  In step S310, the control unit 190 brings the packing 130 and the mask 110 or the mask holder 170 into close contact. When the packing 130 is inflatable, air supply to the packing 130 is started, the packing 130 is inflated and brought into close contact with the mask 110 or the mask holder 170 to form an airtight chamber. Further, when the packing 130 is non-inflatable, the mask holder 170 is lowered to be brought into close contact with the mask 110 or the mask holder 170. Next, the process proceeds to step S315.

  In step S315, the control unit 190 controls the vacuum regulator 155, starts evacuation in cooperation with the vacuum pump 157, and proceeds to step S320. As a result, a downward force is applied to the mask holder 170. Here, the vacuum pressure is the first set value, and can be arbitrarily set in the range of 0 kPa to -10 kPa based on the mask material (glass, acrylic, etc.) and the thickness (5 mm, 8 mm, etc.). it can.

  In step S320, control unit 190 determines whether or not the elapsed time from the evacuation start time is a predetermined value (T1-Δ1). If the elapsed time is less than the predetermined value, the process proceeds to step S320 again. If the elapsed time is greater than or equal to the predetermined value, the process proceeds to step S325. Here, T1 is the time when the approximate center of the mask 110 and the workpiece 120 is in close contact, and is a value set in consideration of the material and thickness of the mask holder 170 in order to realize the present invention. . Δ1 is a minute time, which is a time required to obtain a desired air supply pressure at the time T1 after the start of air supply. That is, it means a preparation time necessary for obtaining a desired air supply pressure at the time of the elapsed time T1. The Δ1 can be automatically calculated by the control unit 190 based on the air pressure of the gas supply source 187 and the like. Of course, it may be set in advance based on the gas supply capacity of the gas supply source 187 in the previous period.

  In step S325, the control unit 190 controls the regulator 185 to start air supply in cooperation with the gas supply source 187 and the electromagnetic valve 180 so that the peripheral part of the mask holder 170 moves upward in the mask upper and lower cylinders 160. The process proceeds to step S330. As a result, the mask holder 170 receives a downward force due to evacuation, and the peripheral portion receives an upward force, so that the mask holder 170 bends in a downward convex shape with a substantially center as a valley. Here, the air supply pressure is the first set value, and can be selected from the range of 1 MPa to 6 MPa.

In step S330, the control unit 190 determines whether or not the elapsed time from the evacuation start time is a predetermined value (T2). When the elapsed time is less than the predetermined value, the process proceeds to step S330 again. If the elapsed time is greater than or equal to the predetermined value, the process proceeds to step S335. Here, T2 is the time when the mask 110 and the workpiece 120 are in close contact with each other. The vacuum pressure is the second set value, and can be selected from the range of 0 kPa to -20 kPa.
Furthermore, the air pressure is the second set value and can be selected from the range of 1 MPa to 6 MPa.

  In step S335, the control unit 190 controls the regulator 185 to open and close the electromagnetic valve 180, thereby reducing the air supply amount for raising the mask holder 170, and proceeds to step S340. Thereby, the center of the mask 110 and the workpiece | work 120 is closely_contact | adhered first, and the contact | adherence process in which a peripheral part contact | adheres gradually is complete | finished. Here, even if the rate of decrease in the air supply amount is arbitrarily set according to the material and thickness of the mask holder 170, the force that pulls the mask holder 170 downward by the vacuuming pressure is compensated or antagonized. As described above, the control unit 190 may perform control.

  In step S340, the control unit 190 stops the lowering of the mask holder 170 or stops air supply to the packing 130, ends the contact process, and proceeds to step S345.

  In step S345, the control unit 190 determines whether or not the elapsed time from the evacuation start time is a predetermined value (T3). If the elapsed time is less than the predetermined value, the process proceeds to step S345 again. If the elapsed time is greater than or equal to the predetermined value, the process proceeds to step S350. Here, T3 is a time required to reinforce the adhesion between the mask 110 and the workpiece 120, and is necessary for obtaining a sufficient adhesion strength between the mask and the workpiece, and is set to a preset vacuum pressure. It is the time required to reach. The vacuum pressure is a third set value, and is selected from the range of −20 kPa to −100 kPa.

  In step S345, the control unit 190 maintains the vacuuming pressure, and proceeds to step S355.

  In step S355, the control unit 190 performs an exposure process, and proceeds to step S360.

  In step S360, the control unit 190 controls the vacuum regulator 155 to stop evacuation, and proceeds to step S365 (elapsed time T4). Here, T4 is a time required for performing the exposure processing after T3, and can be arbitrarily set based on the function and mode of the exposure apparatus.

  In step S365, the control unit 190 raises the mask holder 170, lowers the table 140, or releases the gas in the packing 130, and ends the contact between the workpiece 120 and the mask holder 170.

  In an example of the adhesion process, the values of the set times T1, T2, T3, and T4 based on the elapsed time depend on the material, thickness, and size of the mask 110 and the mask holder 170 to be used, and the vacuuming and air supply capability. It can be set arbitrarily.

  Further, the vacuum pressure and the air supply pressure for each set time can be arbitrarily set according to the material and thickness of the mask 110 and the mask holder 170 to be used. Examples of setting conditions when 5 mm thick acrylic, 5 mm thick glass and 8 mm thick acrylic are used as a mask are shown in Tables 1 to 3 below.

  Various conditions according to the material, thickness, size, and the like of the mask 110 and the mask holder 170 are stored in the storage unit 240 and called by the control unit 220 according to the material and the thickness. It is possible to select an optimum vacuum contact condition according to the material.

  FIG. 4 is a graph showing an example of pressure control in the vacuum contact process of the present invention.

  The evacuation is set to be -5 kPa by time T1, -10 kPa by time T2, -60 kPa by time T3, and -60 kPa is maintained from time T3 to time T4. The

  The air supply pressure is set to be 2 MPa from time T1 to 5 MPa at time T2, and is set so that the air supply pressure decreases after time T2. Here, since it is not possible to obtain a pressure of 2 MPa immediately after the start of air supply, an optimum combination of vacuuming pressure and air supply pressure is realized by starting air supply by a minute time Δ1 from time T1. can do. In addition, after the time T2 has elapsed, the amount of air supply can be reduced over time Δ2, and adhesion from the approximate center of the mask to the peripheral portion can be realized.

  In FIG. 4, the process in each time is as follows. From time 0 to T1, the process is shown until the packing 130 expands, evacuation starts, and the peripheral portion of the mask holder 170 is pulled upward.

  From time T1 to time T2, the mask 110 is bent in a downward convex shape having a valley at the center, and the mask 110 and the workpiece 120 are in close contact with each other gradually from the center toward the periphery.

  After the mask 110 and the workpiece 120 are in close contact with each other at the time T2, the process is shown in which the vacuuming is continued until T3, thereby increasing the adhesion and preventing the occurrence of adhesion failure.

  From time T3 to T4, the contact state is maintained, and after the exposure, the process immediately before the evacuation is stopped is shown.

  After time T4, the process of stopping the vacuuming and releasing the adhesion is shown.

  Next, although the vacuum contact | adherence method based on this invention is demonstrated based on an Example, it is not limited to the said Example.

  Using 5 mm thick acrylic, 5 mm thick glass and 8 mm thick acrylic as a mask, vacuum adhesion was carried out by the vacuum adhesion method according to the present invention.

  In all mask holders, close contact from substantially the center to the peripheral portion was realized, and there was no contact failure such as air remaining at the approximate center.

  FIG. 5 is a graph showing measurement data of the vacuum pressure in the example according to the present invention. Although it is obvious when compared with a comparative example described later, in the vacuum contact method according to the present invention, by operating the mask upper and lower cylinders, it is possible to avoid a sudden increase in vacuum pressure, and thereby the contact surface is substantially centered. It was possible to prevent the occurrence of poor adhesion in which the air remained.

  FIG. 6 is a schematic diagram of vacuum contact according to the present invention, and the vacuum contact process will be described based on the schematic diagram.

  Since the mask upper / lower cylinder 160 is in operation, the mask 110 is bent in a downward convex shape with the valley at the approximate center. As a result, the mask and the approximate center 615 of the workpiece are in close contact with each other. As the evacuation further progresses, a downward force is applied to the mask holder 170, and the peripheral part is in close contact with each other at a stretch. However, as the air supply pressure to the mask upper and lower cylinders 160 increases, the peripheral part is further increased. By pulling upward and maintaining the downward convex shape, as shown at 625 and 635, the contact area can gradually increase toward the periphery.

  As a comparative example, vacuum adhesion was performed using 5 mm thick acrylic and 5 mm thick glass as the mask 110 without operating the upper and lower cylinders of the mask. In this case, air remained substantially at the center, resulting in poor adhesion.

  FIG. 7 is a graph showing vacuum pressure measurement data when a mask upper / lower cylinder is not used as a comparative example. Since the upper and lower cylinders of the mask are not operating, the vacuum pressure suddenly increases in about half the time of the above-described embodiment. For this reason, it has not been possible to go through a process in which the mask and the workpiece are in close contact with each other and gradually contacted from the substantially center to the peripheral portion.

  FIG. 8 is a schematic diagram of vacuum contact in a comparative example, and the vacuum contact process will be described based on the schematic diagram.

  In this example, the mask 110 and the work 120 first come into close contact with each other, and when evacuated, the mask 110 is bent in a downward convex shape, so that it is in close contact with the approximate center 815. However, since the peripheral portion is not lifted by the mask upper and lower cylinders, the mask 110 and the work 120 are brought into close contact with each other by further evacuation. As a result, even if air remains at the approximate center 835, the surrounding contact portion 825 forms an airtight chamber, and the air at the approximate center 835 cannot be removed any more.

It is an example of the functional block diagram of the vacuum contact exposure apparatus using the vacuum contact exposure method of this invention. It is an example of a functional block diagram of the control part of the vacuum contact exposure apparatus using the vacuum contact exposure method of this invention. It is an example of the flowchart which shows the contact | adherence process in the vacuum contact | exposure exposure method of this invention. It is a graph which shows an example of the pressure control in the vacuum contact | adherence process of this invention. It is a graph which shows the measurement data of the vacuum pressure in the Example which concerns on this invention. It is a schematic diagram of vacuum contact according to the present invention. It is a graph which shows the measurement data of the vacuum pressure when not using a mask up-and-down cylinder as a comparative example. It is a schematic diagram of the vacuum contact | adherence in a comparative example.

Explanation of symbols

110 Mask 120 Work 130 Packing 140 Table 150 Vacuum piping system 155 Vacuum regulator 157 Vacuum pump 160 Mask upper and lower cylinder 170 Mask holder 180 Solenoid valve 185 Regulator 187 Gas supply source 190 Control unit

Claims (5)

A step of bringing the packing into close contact with a mask disposed on the table by packing provided on an edge of the table on which the workpiece is placed;
Evacuating to an initial set pressure value, bending the mask in a convex shape and closely contacting the workpiece from the approximate center of the mask;
A step of further evacuating and raising a mask holder for holding the edge of the mask, increasing the deflection of the mask, and further contacting the workpiece toward the edge of the mask; and A step of stopping the lift of the mask holder in response to the close contact with the substantially edge of the workpiece,
A vacuum contact exposure method comprising:   2. The vacuum contact exposure method according to claim 1, wherein the raising of the mask holder is controlled by a cylinder mounted on the mask holder.   3. The vacuum contact exposure method according to claim 2, wherein after the center of the mask comes into contact with the workpiece, the ascending force of the mask holder is suppressed and the vacuum pulling pressure is controlled to be higher than the ascending force of the mask holder. .   The vacuum contact exposure method according to claim 3, wherein the cylinder is lifted by supplying gas. First, only vacuuming is performed, and in response to the vacuum pressure resulting from the vacuuming reaching the first set value, the air pressure reaches the first set value,
Subsequently, evacuation and air supply are performed, and in response to the vacuum pressure reaching the second set value, the air pressure reaches the second set value,
After the air pressure reaches the second set value, stop air supply, release the air pressure,
Continue evacuation until the vacuum pressure reaches the third set value,
5. The vacuum contact exposure method according to claim 4, wherein the vacuum pressure and the air supply pressure are controlled as described above.

Images