JPH08305033A - Exposure device for printed circuit board - Google Patents

Abstract

PURPOSE: To precisely control exposure by providing an exposure device with a means measuring the quantity of light transmitted through an exposure wavelength transmission body and a means controlling the exposure based on the measured result. CONSTITUTION: A circuit board 2 being an object to be exposed is placed on a stage 1 and an art work film 3 on which a circuit pattern is drawn is placed thereon. Besides, a transparent film 4 is placed thereon and the circumference of a gap between the stage 1 is hermetically sealed by packing 5. By vacuum- sucking air in a gap between the film 4 and the stage 1 through a communicating hole 6, the film 3 is pressed and closely brought into contact with the substrate 2 by the film 4. In such a state, ultraviolet rays are radiated from a light source 7. Then, a light quantity sensor 8 is embedded in the upper surface of the stage 1 so as to detect the light quantity by receiving the ultraviolet rays from the upper part of the stage 1. The signal of the light quantity detected by the sensor 8 is inputted to a controller 15 and the light quantity is controlled by the controller 15 according to the detected light quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for printed boards.

[0002]

2. Description of the Related Art In recent years, when a printed circuit board is produced, a lithography method used for manufacturing an integrated circuit has been adopted, and an exposure apparatus for a printed circuit board is used in such a method. In the exposure equipment for printed circuit boards, an artwork film that is easy to handle is used as an original plate on which a circuit pattern has been drawn, and it is necessary to bring this artwork film into close contact with the substrate during exposure. It is usual to expose while holding the artwork film with a transparent film or transparent acrylic plate that can be transmitted.
Therefore, exposure is performed from the upper exposure light source in a state where the artwork film and the transparent film (or acrylic plate) are overlapped on the substrate.

[0003]

However, in the conventional exposure apparatus, since the exposure light amount is measured above the transparent film or the acrylic plate, the amount of light actually transmitted through the transparent film or acrylic plate and reaching the substrate is Has a problem that it cannot measure the light quantity accurately and therefore cannot control the light quantity accurately. The present invention aims to solve the above-mentioned problems of the prior art.

[0004]

In order to achieve the above object, the present invention provides an exposure apparatus for a printed circuit board, which is provided with an exposure wavelength transmitter for bringing an artwork film into close contact with the substrate. It is characterized in that it is provided with means for measuring the amount of light after passing through and means for controlling the exposure amount based on the measurement result by the means for measuring. With such a configuration, the amount of light transmitted through the exposure wavelength transmitter can be measured, and the exposure amount can be accurately controlled. It is also possible to measure the amount of light after passing through the transparent portion of the artwork film in addition to the exposure wavelength transmitter, and by configuring in this way, it is possible to measure the amount of light more accurately. The exposure wavelength transmitter may be a film, or an acrylic plate or the like.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a vacuum contact type exposure apparatus. A substrate 2 to be exposed is placed on a stage 1, and an artwork film 3 having a circuit pattern drawn thereon is placed on the substrate 2. A transparent film 4 is further mounted on this, and the periphery of the stage 1 is sealed by a packing 5. The air in the space between the transparent film 4 and the stage 1 is connected to the communication hole 6
The artwork film 3 is pressed by the transparent film 4 to be brought into close contact with the substrate 2 by vacuum suction via the. Then, in this state, the light source 7 irradiates ultraviolet rays. A light amount sensor 8 is embedded in the upper surface of the stage 1, and is configured to receive ultraviolet light from above the stage 1 and detect the light amount. The mounting position of the light amount sensor 8 is a portion around the mounting portion on which the substrate 2 is mounted and covered by the transparent film 4. In addition, the position above which there is nothing to block the exposure from the light source 7 is set. The light amount signal detected by the light amount sensor 8 is input to the control device 15, and the light amount control corresponding to the detected light amount is performed by the control device 15. According to the embodiment described above, the ultraviolet light, which is the exposure light from the light source 7, is detected by the light amount sensor 8 after passing through the transparent film 4, and a value close to the light amount actually applied to the stage 1 is detected. Therefore, the control device 15 can accurately control the light amount.

FIG. 2 shows an embodiment in which the present invention is applied to a pressure contact type exposure apparatus. A substrate 2'which is an exposure target is placed on a stage 1 ', and an artwork film 3'on which a circuit pattern is drawn is placed on the substrate 2'. A transparent film 4'is installed above this. The transparent film 4'is attached to the frame 10, and the glass 9 is fitted in the central portion of the frame 10 so that the ultraviolet rays from the light source 7'are transmitted. The frame 10 is provided with a communication hole 11 from which the transparent film 4'is inflated by filling the inside of the transparent film 4'with air so that the artwork film 3'is brought into close contact with the substrate 2 '. ing. Then, similarly, the light source 7 ′ irradiates ultraviolet rays to perform exposure. Similarly, a light amount sensor 8'is embedded in the upper surface of the stage 1 ', and is configured to detect the light amount by receiving ultraviolet rays from above the stage 1'. Similarly, the mounting position of the light amount sensor 8 ′ is a portion around the mounting portion on which the substrate 2 ′ is mounted and covered by the transparent film 4 ′. Further, the position is such that there is no object that blocks the exposure light from the light source 7 ′ above. The signal of the light amount detected by the light amount sensor 8'is similarly input to the control device 15 ', and the light amount control corresponding to the detected light amount is performed by the control device 15'. According to this embodiment, since the ultraviolet ray from the light source 7'is detected by the light amount sensor 8'after passing through the glass 9 and the transparent film 4 ', the value close to the light amount actually radiated to the stage 1'is obtained. The detected light amount can be accurately controlled by the control device 15 ′.

In the above embodiment, the circumference of the artwork film 3, 3'is extended so as to cover the light quantity sensor 8, 8 ', and the light quantity of the exposure light transmitted through the artwork film 3, 3'is detected. It can also be configured to do so. With such a configuration, more accurate light amount detection is possible.

[0008]

As described above, the exposure apparatus for a printed circuit board of the present invention, based on the means for measuring the amount of light after passing through the exposure wavelength transmitting body and the measurement result by the means for measuring, Since the means for controlling the exposure amount is provided, the amount of light transmitted through the exposure wavelength transmitting body can be measured, and the exposure amount can be accurately controlled. In addition, when the light amount after passing through the transparent portion of the artwork film is measured in addition to the exposure wavelength transmitting body, there is an effect that a more accurate light amount can be measured.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an embodiment of the present invention.

FIG. 2 is a schematic front view showing another embodiment of the present invention.

[Explanation of symbols]

1: stage, 2: substrate, 3: artwork film,
4: transparent film, 5: packing, 6: communication hole, 7: light source, 8: light amount sensor, 9: glass, 10: frame, 11: communication hole, 15: control device.

Claims (4)

[Claims] 1. An exposure apparatus for a printed circuit board, comprising an exposure wavelength transmitting body for bringing an artwork film into close contact with a substrate, and means for measuring the amount of light after passing through the exposure wavelength transmitting body, and the measurement. An exposure apparatus for a printed circuit board, comprising: a means for controlling an exposure amount based on a measurement result by the means for. 2. The exposure apparatus for a printed circuit board according to claim 1, wherein the means for measuring measures the amount of light after passing through the transparent portion of the artwork film in addition to the exposure wavelength transmitting body. 3. The exposure apparatus for a printed circuit board according to claim 1, wherein the exposure wavelength transmitter is a film. 4. The exposure apparatus for a printed circuit board according to claim 1, wherein the exposure wavelength transmitting body is an acrylic plate.