JPH0542153B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is necessary for mounting electronic equipment that satisfies functions such as fixed support of electronic components, functional connections between components, and insulation between components and connections. The present invention relates to a method of manufacturing a printed wiring board.

[Conventional technology]

FIG. 4a is a process diagram showing a conventionally commonly used method for manufacturing a printed wiring board, and b to h are partial sectional views showing the state of the printed wiring board in each step of a. In the figure, 1 is an insulating substrate such as glass epoxy, 2 is a conductive layer such as copper plating, 2a is a formed wiring pattern, 3 is a through hole, 4 is a resin layer that is cured by cross-linking polymerization reaction with light, 4a is an etching resist obtained by hardening the photosensitive resin layer 4, 5 is a mask film for forming a wiring pattern, and 6 is light from, for example, a mercury lamp.

Next, the manufacturing method will be explained. First, CAD
A through hole 3 is drilled in the insulating substrate 1 based on the drilling data 11b created by (Computer Aided Design). Next, as shown in FIG. 4b, a conductor layer 2 such as copper plating is formed on the insulating substrate 1. At this time, the conductor layer 2 is also formed in the through hole 3 portion. The thickness of the conductor layer 2 is, for example, 20~
It is 30 μm. Next, as shown in c, a resin layer 4 that is cured by cross-linking polymerization reaction is applied to the insulating substrate
be applied to both sides. As the resin layer 4, a dry film type material such as polyacrylic acid-based SUNFORT made by Asahi Kasei is used, and the through holes 3 are tented. Next, as shown in d, the mask film 5 created based on the artwork data 11a is overlaid and aligned on the insulating substrate 1, and as shown in e, light 6 from a mercury lamp or the like is applied using an exposure machine (not shown). irradiate. At this time, as shown by f, only the portion of the resin layer 4 that is exposed to the light is hardened and remains after development, becoming an etching resist 4a.
Next, as shown in g, the conductor layer 2 is etched, and as shown in h, the etching resist 4 is etched.
When a is peeled off, a wiring pattern 2a is formed.

Next, creation of a mask film based on the artwork data 11a will be briefly explained. first,
An enlarged original drawing is created using a digitizer (not shown). Edit this after inspecting it. The original drawing is then photographed in a reduced size and printed on multiple sides to create a mask film.

[Problem that the invention seeks to solve]

The conventional printed wiring board manufacturing method described above requires an artwork process for creating the mask film 5, and this process takes a lot of time.
This becomes a problem when performing high-mix, small-lot production.
Further, it takes time and effort to align the mask film 5 and the insulating substrate 1 and perform exposure. There are problems such as scratches on the mask film 5 causing defects and the need to store the mask film 5.

As a solution to these problems, there is a method of using a laser device as shown in FIG. 5 for patterning exposure without a mask. For example,
This was presented in the specifications for the high-precision laser direct drawing device [Nikon LP-3000D] published by Nippon Kogaku Kogyo Co., Ltd.'s Precision Equipment Sales Department in June 1985. In the figure, 51 is an argon ion laser. oscillator, 52 an optical modulator that turns on/off the laser beam, 53 a mirror that reflects the laser beam, 54 a lens that focuses the laser beam, 55
is a polygon mirror for scanning the laser beam,
56 is an fθ lens that corrects the focus of the laser beam;
57 is a bending mirror for directing the laser beam downward, and 58 is a table for holding and moving the insulating substrate.

This device uses a raster method in which a pattern is drawn by beam scanning using a polygon mirror 55 on one axis and by moving a table 58 on a vertical axis. Therefore, it is necessary to convert the manufacturing data to create raster data, and this data conversion takes a lot of time. Additionally, this device has many mechanically driven parts, resulting in a long drawing time and a lack of reliability.

This invention was made to solve the above-mentioned problems. It allows patterning exposure without a mask without converting a large amount of drawing data, supports high-mix, low-volume production, and also reduces mechanical drive parts. An object of the present invention is to obtain a method of manufacturing a printed wiring board that requires less damage.

In addition, as a prior art that belongs to this technical field, there is also Japanese Patent Application Laid-Open No. 54-18301 entitled "Optical scanning device and scanning method for exposing a photosensitive surface with a laser beam".
There is.

[Means for solving problems]

The method for manufacturing a printed wiring board according to the present invention includes a step of providing an electron-sensitive resin layer that is cured by an electron beam on an insulating substrate, and aligning the insulating substrate with the electron-sensitive resin layer and an electron beam, and Etching resist is formed by performing a step of direct patterning exposure using a vector method using an electron beam.

[Effect]

In this invention, since patterning exposure is performed directly with an electron beam without using a mask film, the complicated artwork process can be omitted, productivity can be improved and production can be made more flexible, and defects such as scratches on the mask film can be avoided. There will be no storage problems. Further, since the electron beam can be electrically controlled, stable drawing can be performed using the vector method, and there is no need for extensive data conversion.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1a is a process diagram showing a method for manufacturing a printed wiring board according to an embodiment of the present invention, and b to h are a
FIG. 3 is a partial cross-sectional view showing the state of the printed wiring board in each step of FIG. In the figure, (EB) is an electron beam. In this case, the resin layer 4 is made of electron beam (EB)
However, since many organic polymers are cured by electron beam (EB), for example, Asahi Kasei's polyacrylic acid-based
A dry type such as SUNFORT can also be used.

Next, the operation will be explained mainly focusing on the differences from the conventional example. That is, as shown in FIGS. 1b and 1c, the insulating substrate 1 on which the through holes 3 are provided, the conductor layer 2 is formed, and the resin layer 4 is provided is similar to the conventional example shown in FIGS. 4d and e. Patterning exposure is performed by directly drawing along the wiring pattern with an electron beam, as shown in FIGS. 1d and 1e, without using the mask film 5. At this time, if wiring patterns are to be formed on both the front and back sides of the insulating substrate 1, it is necessary to expose both sides, but as shown in FIG. Since the positioning is performed by scanning and monitoring the reflected electrons (RB) by the reflected electron sensor 21 and the signal processing unit 22, the positioning can be performed simply and reliably.

FIG. 3a is an explanatory view for explaining the beam scanning method, and FIG. 3b is an explanatory view showing an enlarged view of the electron beam irradiation section shown in a. In the figure, 4a is the exposed portion of the resin layer, that is, the etching resist, and 4b is the etching resist.
indicates the part currently irradiated with the electron beam.
As shown in this figure, the scanning method of the electron beam is a vector method of scanning along the wiring pattern. Now, if the electron beam is formed into a rectangle of 100 μm x 100 μm and a resist with a sensitivity of 1×10 ^-6 c/cm ² is used, and the beam current is 10 μA, the irradiation time required for exposure is The beam stop time is 10μsec or more. That is, the linear velocity of the beam at arrow A must be 10 m/sec or less. When moving in the direction of arrow B, the beam is moved sufficiently faster than 10 m/sec without stopping, so that it is not exposed.

In order to form an electron beam into a rectangular shape of 100 μm×100 μm, it is possible, for example, to vibrate a beam with a spot diameter of about 10 μm at a high frequency.

In the above embodiment, the beam current was set to 10 μA, but the beam current can be increased further if the response of the beam deflection amplifier (not shown) is good. In this case, the linear velocity of the electron beam becomes even faster, improving productivity.

When the beam current is decreased, the irradiation time must be increased accordingly, and the total exposure time becomes longer. In order to shorten the exposure time compared to conventional methods using mercury lamps, etc., a beam current of 1 μA or more is usually desired, although it depends on the size of the printed wiring board.

Furthermore, in order to reduce the frequency of positioning due to movement of the processing room table (not shown), the area to be drawn by beam deflection is set to 10 mm x 10 mm or more. That is, if this area is small, the frequency of mechanically moving the processing chamber table increases when writing on the entire surface of the insulating substrate, making the exposure process longer. In order to complete the exposure process in a shorter time than the conventional method,
10mm x 10mm or more is desirable.

Furthermore, in the above embodiment, the beam is 100 μm×
Although it is formed in a rectangular shape of 100 μm, it goes without saying that wiring patterns with various line widths can be accommodated by changing this size.

〔Effect of the invention〕

As described above, according to the present invention, there is a step of providing an electron-sensitive resin layer that is cured by an electron beam on an insulating substrate, and aligning the insulating substrate on which the electron-sensitive resin layer is provided with an electron beam, and Since the etching resist is formed through a process of direct patterning exposure using a vector method using a beam, patterning exposure can be performed without a mask without the need to convert a large amount of drawing data. This has the effect of providing a printed wiring board manufacturing method that requires fewer drive units.

[Brief explanation of the drawing]

FIG. 1a is a process diagram showing a method for manufacturing a printed wiring board according to an embodiment of the present invention, b to h are partial cross-sectional views showing the state of the printed wiring board in each step of a, and FIG. FIG. 3a is an explanatory diagram explaining the beam scanning method, b is an explanatory diagram showing an enlarged view of the beam irradiation section shown in a, and FIG. 4a is a conventional diagram. Fig. 5 is a process diagram showing the method for manufacturing a printed wiring board, b to h are partial sectional views showing the state of the printed wiring board in each step of a, and Fig. 5 is a configuration diagram showing a conventional laser device for patterning exposure. It is. In the figure, 1 is an insulating substrate, 1a is a reference position mark, 2 is a conductive layer, 2a is a formed wiring pattern, 3 is a through hole, 4 is a resin layer, 4a is an exposed part, that is, an etching resist, and 4b is a current The part irradiated with the beam, 5 is the mask film, 6 is the light, 21 is the reflection electron sensor, 22 is the signal processing unit, (EB) is the electron beam, (RB)
is a reflected electron. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. Through holes are provided in an insulating substrate to form a conductor layer, and etching resist is formed on the portions that will become the circuit, the portions that will be the pads, and the through hole portions, and the conductive layer is covered with the etching resist. A method for manufacturing a printed wiring board in which a wiring pattern is formed by etching away a portion of the conductor layer that is not present, including a step of providing an electrosensitive resin layer that is cured by an electron beam on the insulating substrate, and providing the electrosensitive resin layer. A method for producing a printed wiring board, characterized in that the etching resist is formed by aligning an insulating substrate with an electron beam and performing direct patterning exposure using the electron beam using a vector method. 2 To align the insulating substrate and the electron beam,
A method for manufacturing a printed wiring board according to claim 1, which utilizes reflected electrons. 3 The drawing area due to electron beam deflection is 10mm x 10
3. The method for manufacturing a printed wiring board according to claim 1 or 2, wherein the printed wiring board is larger than or equal to mm. 4. The method for manufacturing a printed wiring board according to any one of claims 1 to 3, wherein the beam current is 1 μA or more.