JP2614701B2 - Exposure method and apparatus for non-planar substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for accurately and accurately performing wiring circuit exposure and drawing on non-planar substrates having irregularities or curved surfaces such as three-dimensional molded substrates, molded substrates, warped substrates, and flexible substrates. About.

[0002]

2. Description of the Related Art With the rapid progress of recent electronics, printed circuit boards have become more and more important as basic components of various products as well as electric products. In addition, the printed circuit configuration is becoming extremely complicated and multi-layered, and there is an increasing demand for a printed circuit board design and a reduction in the manufacturing period in accordance with a reduction in the product cycle. Printed circuit board design starts with circuit design, performs pattern design, and becomes production data output. Circuit drawing is C
It has been automated by AD / CAM. A printed circuit board is manufactured by performing etching and coating based on a circuit diagram. For that purpose, a step of exposing a photosensitive layer provided on the substrate surface using a printed circuit printed film on the substrate surface is necessary. .

Next, when forming an image on a substrate surface by exposure, there is a contact work as an intermediate step of forming a photomask. Depending on the application, the equipment is large or small. The main one is to install a light source on the first floor of the building, and have an operation panel and a large glass surface of 10 mm thick, 3 m long and 3 m wide on the second floor, and close contact reversal within that range There are printers that can handle fine patterns and printers for fine patterns. This is, in principle, the same as a daylight photograph in which the sun is replaced with an electric light source, and simply irradiates light with a thick plate and a raw material (film or glass dry plate). A transparent glass is provided in the contact portion, and a rubber sheet portion for bringing the original plate and the raw material into close contact with each other is provided thereon. This is a shape covering the entire glass surface. Tungsten lamps, high-pressure mercury lamps, halogen lamps, and the like are used as internal light sources depending on the application. In the adhesion step, a film surface (emulsion surface with an image) is set on a clean glass surface on an original plate, and a raw film is set thereon with the film surface down. Cover with the rubber sheet, extract the air between the glass surface and the rubber sheet with a vacuum pump, and at the same time, squeeze with a roller or the like from the top of the rubber sheet to avoid generating vacuum unevenness, complete vacuum, and expose, At the end of the adhesion step, the exposure step starts.

[0004] However, the above method cannot provide a sufficient degree of adhesion to a substrate having an uneven surface or a curved surface. When the substrate surface is in one direction and the step is small, it can be incompletely adhered, but when the step is large, when it has a step in two or more directions, when there is unevenness in the center of the substrate, when the substrate surface is curved In such a case, it is difficult to make the printed circuit film adhere to the printed circuit. A conventional method for providing a printed circuit on a substrate having an uneven surface is to prepare a press die according to the substrate shape, put a film on which a wiring circuit is printed, and press it. Pressing a flat film for the part stretches the film on the inclined surface of the concave or convex part, deforms the wiring circuit, and causes the elongation and cracking of the printed line width,
There is a problem that the exposure is not uniform and causes a product defect. Another conventional technique is to print wiring on the film surface, put the film in a mold, pour a transparent resin liquid over the film, take out the cured resin, mold it again, and expose it. is there. Even with this method, the film is stretched on the inclined surface of the uneven portion, and the process is complicated in addition to the problem of disconnection of the wiring circuit and uneven exposure amount, and these are complicated for the non-planar substrate. It was not enough as a wiring technology.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for performing high-speed, accurate and reliable wiring circuit exposure drawing on a non-planar substrate having irregularities or curved surfaces. It is particularly useful for automating exposure drawing.

[0006]

As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by exposing each portion of the substrate surface from a vertical direction, and have reached the present invention. That is, the present invention includes the following (1) to (5). (1) In a method of exposing a non-planar substrate having irregularities or a curved surface on the substrate surface, (i) irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves and measuring the intensity of the regression reflection thereof. The vertical direction of the portion is detected, (ii) the sealable telescoping prism is operated so that light is irradiated from the detected vertical direction, and (iii) each portion of the substrate surface has passed through the wiring circuit printed film surface. A method for exposing a non-planar substrate, comprising irradiating light vertically.

(2) In a method of exposing a non-planar substrate having irregularities or a curved surface on the substrate surface, (i) irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves, and the intensity of its reflex reflection. Detecting the vertical direction of the portion by measurement, (ii)
The irradiation direction of the glass fiber having a spherical glass tip with a cover is operated so that light is irradiated from the detected vertical direction, and (iii) the light transmitted through the printed wiring circuit film surface is vertically applied to each part of the substrate surface. Irradiating a non-planar substrate. (3) When irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves and detecting the vertical direction of the parts by the recursive reflection, detection of the amount of light by a CCD camera or detection by an ultrasonic sensor; and The method for exposing a non-planar substrate according to (1) or (2), wherein the direction of irradiation of a glass fiber having a spherical glass tip with a cover-type telescopic prism or a cover is controlled using an automatic focusing mechanism.

(4) In an exposure apparatus for a non-planar substrate having irregularities or a curved surface on the substrate surface, (i) irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves, and the intensity of the regression reflection thereof. A vertical direction detector for detecting the vertical direction of the portion by measurement, (ii) a sealed telescopic prism that operates so that light is irradiated in the detected vertical direction, or a glass fiber having a spherical glass tip with a cover, (Iii)
An exposure apparatus for a non-planar substrate, comprising: an automatic focusing mechanism. (5) The apparatus for exposing a non-planar substrate according to (4), wherein the vertical direction detector is a CCD camera or an ultrasonic sensor.

The term "non-planar substrate" as used in the present invention is not a normal printed circuit board on which conductors are wired on a flat substrate, but rather for various reasons such as high density, arrangement of parts, and three-dimensional wiring pattern. With irregularities and curved surfaces on the surface,
For example, a three-dimensional molded substrate, a molded substrate, a warped substrate, a flexible substrate, and the like can be given. In order to find the unevenness and the curved surface of each part, and to detect the vertical direction, in the present invention, non-photosensitive light or ultrasonic waves are irradiated toward the substrate surface from the scanning light emitting unit or ultrasonic oscillation unit, and the substrate surface is irradiated. The point at which the intensity of the non-photosensitive light or ultrasonic waves that are regressively reflected is peaked
This is performed by obtaining data with a light receiver such as a D camera or an ultrasonic sensor and converting the data. In this case, if there is an uneven portion or a curved surface on the substrate surface during scanning, the reflection intensity at this portion becomes weak or zero, and therefore, for such a portion, the light emitting unit or the ultrasonic oscillation unit is again used. By changing the angle and scanning while shaking the head, the peak of the reflection intensity is digitized together with the direction and recorded. However, when the data at the time of design can be used for the substrate surface, the process is simplified and the design data can be converted into data in the vertical direction. Also, a plurality of sensors can be used as described below.

FIGS. 1 and 2 illustrate the principles of the present invention. The non-planar substrate 1 has planes 2, 3, and 4 having a step. As shown in FIG. 1, a plane portion 3 parallel to the entire surface of the substrate
, A projector 5 for irradiating non-photosensitive light or ultrasonic waves
The non-photosensitive light or the ultrasonic wave applied to the plane 3 is reflected by the plane, and the incident angle and the reflection angle are equally reflected with respect to the perpendicular to the plane from the exposure device, and enters the detector 6 on the extension of the line. . The fact that the non-photosensitive light or ultrasonic wave is detected by the detector in this way allows the exposure to be performed perpendicularly to the plane 3. On the other hand, in the case of a non-planar substrate, the surface to be exposed may be inclined with respect to the entire surface of the substrate, for example, as in the plane portion 4 in FIG. As shown in FIG. 2, the non-photosensitive light or the ultrasonic wave emitted from the projector 5 is reflected by the plane 4, but is not detected by the detector 6 at a predetermined position. From this, it is determined that the plane 4 is an inclined plane or a non-plane. By changing the positional relationship between the detector 6 and / or the projector 5 and the plane 4, the positional relationship obtained when the non-photosensitive light or the ultrasonic wave is captured by the detector 6 is changed from the position perpendicular to the inclined plane 4 to the exposure position. Will give you the information you need to do. Based on this information, it is also possible to expose the inclined plane portion 4 from the vertical direction.

One specific method for detecting the vertical direction will be described with reference to infrared rays. A projector consisting of one infrared light emitting element, and the incident infrared light reflected from the substrate plane is made equal to the incident angle and the reflection angle, in other words, the exposure direction is correctly oriented perpendicular to the substrate plane. In addition to the combination of one detector comprising an infrared sensor provided at a position and a direction for sensing the reflected infrared light, one or two or more infrared sensors for contrast comparison are provided near the infrared sensor. Place. By comparing the amount of light received by the main infrared sensor with that of the contrast comparison infrared sensor and activating the vertical detector while searching for the direction in which the difference becomes stronger, ultimately only the main infrared sensor emits infrared light. When the positional relationship for detection is reached, it indicates that the vertical detector is parallel to the substrate surface. Non-photosensitive light is light that does not react with the photosensitive layer coated with the photosensitive resin on the substrate surface, and light of a wavelength at which the photosensitive resin has no sensitivity, infrared light,
It is selected from ultraviolet rays and used. As the light source, various lamps with filters, light emitting diodes, lasers, and the like are used.

The vertical direction of each portion of the substrate surface is detected by the retroreflective detector using these lights or ultrasonic waves. When the vertical direction of each part of the substrate surface is detected, light is irradiated toward the substrate from the detected vertical direction based on the data. This light, unlike non-photosensitive light, reacts with the photosensitive resin, and its wavelength is determined by the photosensitive resin used. In order to change the direction of the light to be irradiated, the present invention uses a hermetic telescopic prism or a glass fiber having a spherical glass tip with a cover. A sealed telescoping prism is one in which a transparent liquid and a transparent resin liquid are sealed in a container having a belly-shaped telescopic side, and a light incident surface is parallel to a light projecting surface. The hour light travels linearly, but when the incident surface and the projection surface are not parallel, the light acts as a prism and refracts and travels. In the sealed telescoping prism of the present invention, the actuator can change the incident surface and the projection surface according to the vertical data obtained in the previous step, and irradiate light in the desired vertical direction of each part of the substrate. .

On the other hand, a glass fiber having a spherical glass tip with a cover has the same principle as an endoscope such as a gastroscope, and is shown in FIG. The tip of the glass fiber 14 has a spherical shape 15 and a reflector or cover 16 for irradiating light only in a specific direction surrounds the spherical portion. In the case of FIG.
The opening 17 is opened. The direction of the reflector or the cover can be freely changed by one or more control rods 18 juxtaposed with the glass fiber, so that the light projection direction can be freely changed. The substrate is exposed to light from a light source by vertically irradiating each portion of the substrate from the above-mentioned sealed telescoping prism or glass fiber, and transmitted through the printed circuit printed circuit film to cause a photochemical reaction of the photosensitive resin layer. At this time, the light source can accurately expose the substrate surface by the autofocus mechanism based on the data in the vertical direction. By the method or the apparatus as described above, it is possible to draw a precise and accurate wiring even on the three-dimensional surface of the substrate. After the exposure step of the present invention,
The wiring board is completed by ordinary means such as etching and / or coating.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows an exposure method and apparatus according to the present invention. When exposing a certain portion of the non-planar substrate 1, non-photosensitive light or ultrasonic waves are emitted toward the substrate from the projector 5, and the reflected light or ultrasonic waves are detected by the detector 6. Both 5,6
If the vertical detector 7 having a position parallel to the substrate surface is detected by the detector 6, it is completely sensed by the detector 6, but if the vertical detector 7 is not positioned parallel to the substrate surface, reflected light or ultrasonic waves Is not sensed or is sensed weakly, so that the vertical detector 7 is operated so as to obtain the most strongly sensed positional relationship. After the vertical direction detector 7 was made parallel to the substrate surface in this manner, exposure was performed.

In the exposure, light projected from a lamp 8 passes through a film 9 (roll-to-roll in FIG. 3) on which a wiring pattern is drawn and a flat glass 10,
It enters the sealed telescopic prism 12. Lenses 11 and 13 are appropriately provided at both ends of the sealed telescopic prism, and are designed to have a desired reduced scale on the substrate surface after transmitting through the projected optical wiring pattern film.
The projected light has its traveling direction bent by the refractive index of the medium in the sealed drawable prism, and is projected on the substrate surface in a vertical direction by the vertical position detector 7 when exiting the prism. The above operation is also performed on a plane or a curved surface that is non-parallel to the entire surface of the substrate. As a result, all surfaces of the non-planar substrate are exposed from the vertical direction, and irregularities and curves are formed. It was possible to expose and draw a wiring pattern accurately and at high speed on the non-planar substrate. These operations and equipment can be automated. As another embodiment of the present invention, a glass fiber having a spherical glass tip with a cover shown in FIG. 4 was used in place of the sealed telescopic prism shown in FIG.
The operation of the projection port 17 provided in the cover was performed based on the data obtained by the vertical direction detector so that the control rod 18 constantly irradiated the non-photosensitive light vertically to the substrate surface.

[0016]

As described above, according to the present invention, there is provided a method and apparatus for performing exposure drawing of a wiring circuit on a non-planar substrate having irregularities or a curved surface at high speed, accurately and reliably.

[Brief description of the drawings]

FIG. 1 is a diagram showing the principle of the present invention;

FIG. 2 illustrates the principle of the present invention;

FIG. 3 shows one embodiment of the present invention;

FIG. 4 shows a glass fiber having a spherical glass tip with a cover used in the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Non-planar substrate 2 Substrate surface portion 3 Substrate surface portion 4 Substrate surface portion 5 Projector 6 Vertical detector 8 Lamp 9 Wiring pattern film 10 Flat glass 11 Lens 12 Sealable telescopic Prism 13 Lens 14 Glass fiber 15 Glass fiber spherical tip 16 Cover 17 Projection port opened in cover 18 Control rod

Claims (5)

(57) [Claims] 1. A method of exposing a non-planar substrate having irregularities or a curved surface on the surface of the substrate, comprising the steps of: (1) irradiating non-photosensitive light or ultrasonic waves to each part of the substrate surface and measuring the intensity of the regression reflection thereof; (2) Activate the sealable telescopic prism so that light is emitted from the detected vertical direction. (3) Print the wiring circuit printed film surface on each part of the substrate surface. A method for exposing a non-planar substrate, wherein the transmitted light is irradiated vertically. 2. A method for exposing a non-planar substrate having irregularities or a curved surface on the surface of the substrate, comprising: (1) irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves, and measuring the intensity of the regression reflection thereof; (2) operating the irradiation direction of the glass fiber having a spherical glass tip with a cover so that light is irradiated from the detected vertical direction, and (3) each part of the substrate surface Irradiating light transmitted through a wiring circuit printing film surface vertically to the non-planar substrate. 3. Irradiating non-photosensitive light or ultrasonic waves to each part of the substrate surface, and detecting the light amount by a CCD camera or detecting by an ultrasonic sensor when detecting the vertical direction of the part by regression reflection. 3. The method for exposing a non-planar substrate according to claim 1, wherein an irradiation direction of a glass fiber having a tip end of a spherical glass with a cover and a retractable prism or a cover is controlled using an automatic focusing mechanism. 4. An exposure apparatus for a non-planar substrate having irregularities or a curved surface on the surface of the substrate, wherein: (1) irradiating each part of the substrate surface with non-photosensitive light or ultrasonic waves and measuring the intensity of regression reflection thereof; (2) a vertical detector that detects the vertical direction of the portion, (2) a sealed telescopic prism that operates so that light is irradiated in the detected vertical direction, or a glass fiber having a spherical glass tip with a cover. 3) An exposure apparatus for a non-planar substrate, which has an automatic focusing mechanism. 5. The apparatus according to claim 4, wherein the vertical direction detector is a CCD camera or an ultrasonic sensor.