JP2001177219A - Manufacturing method of circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance productivity by reducing the irradiation treatment time of electromagnetic waves, such as laser. SOLUTION: A catalyst for plating and its compound are deposited onto the surface of an insulating base material 1 for forming a plated foundation layer 2. Electromagnetic waves, such as those of laser, are applied to the boundary region between a circuit part 3 of the insulating base material and a non- circuit part 4 corresponding to the pattern of the non-circuit part 4, thus dispensing with the plated foundation layer 2 of an irradiation part where the electromagnetic waves such as laser are applied, while the non-irradiation part remains. After that, plating is made to the plated foundation layer 2. The irradiation of the laser or the like is made to the boundary region of the circuit part 3 in the non-circuit part 4, and there is not need to apply laser to the entire surface of the wide region of the non-circuit part 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a circuit board obtained by forming a circuit on the surface of a planar or three-dimensional insulating substrate.

[0002]

2. Description of the Related Art In manufacturing a circuit board by forming a circuit on the surface of an insulating base material, a portion of a non-circuit portion serving as an insulating portion between the circuits is irradiated with a laser or the like so that plating is applied to this portion. Japanese Patent Application Laid-Open No. 4-263490 and Japanese Patent Application Laid-Open No. Sho 61-68 disclose a technique in which processing is performed so as not to be performed, and thereafter plating for forming a circuit is performed.
92, and Japanese Patent Application Laid-Open No. 3-122287.

[0003] That is, JP-A-4-263490 relates to a "method of manufacturing a thin film circuit", in which a conductive thin film is formed on an insulating substrate, and the conductive thin film is irradiated with a laser beam through a patterned photomask. The conductive thin film is removed by electroless plating or electroplating on the conductive thin film pattern to deposit a conductor, thereby forming a plated conductive pattern.

Japanese Patent Application Laid-Open No. 61-6892 relates to "a method for manufacturing a printed circuit", in which a substrate provided with a catalyst for a chemical plating reaction on its surface is irradiated with high-intensity light such as laser light in a pattern. After the catalytic action is reduced or eliminated, a printed circuit is formed by selectively plating a non-irradiated portion with high intensity light by chemical plating.

Further, Japanese Patent Application Laid-Open No. 3-122287 relates to a "method of metallizing a substrate", in which a catalyst layer is deposited on a substrate, and the catalyst layer is activated or passivated by irradiating ultraviolet rays locally. After the activation, the activation area is plated or the like.

[0006]

As described above, Japanese Patent Laid-Open No.
-263490 and JP-A-61-6892,
In Japanese Unexamined Patent Publication No. 3-122287, a circuit board is manufactured by providing a step of irradiating a non-circuit portion of an insulating base material with a laser, ultraviolet light, or the like. A laser, ultraviolet light, or the like is applied to the entire surface of the non-circuit portion so that plating is not performed on the entire surface of the non-circuit portion. However, when the entire surface of the wide area of the non-circuit portion is irradiated with the laser, the ultraviolet light, or the like, there is a problem that the irradiation time of the laser, the ultraviolet light, or the like is long and the productivity of the circuit board is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a method of manufacturing a circuit board capable of shortening the irradiation time of an electromagnetic wave such as a laser and improving productivity. Things.

[0008]

According to the method of manufacturing a circuit board of the present invention, a plating catalyst and a compound of a plating catalyst are adhered to the surface of an insulating base material 1 to form a plating base layer 2;
By irradiating the boundary region between the circuit portion 3 and the non-circuit portion 4 of the insulating base material 1 with an electromagnetic wave such as a laser corresponding to the pattern of the non-circuit portion 4, the electromagnetic wave such as a laser is emitted while leaving the non-irradiated portion. It is characterized in that plating is performed on the plating underlayer 2 after removing the plating underlayer 2 in the irradiated portion.

[0009]

It is necessary to irradiate an electromagnetic wave such as a laser along the boundary region between the non-circuit portion 4 and the circuit portion 3 of the insulating base material 1 to irradiate the entire surface of the non-circuit portion 4 with the electromagnetic wave. Instead, the circuit 5 can be formed on the circuit portion 3 by plating. Even if the non-circuit portion 4 is plated, the circuit portion 3 is separated and insulated from the circuit portion 3 by irradiation of an electromagnetic wave such as a laser, so that there is no particular problem in the circuit performance of the circuit board.

[0010]

The present invention will be described below in detail with reference to examples.

FIG. 1 shows an embodiment of the present invention. As an insulating substrate 1, a substrate made of an electrically insulating material such as polyimide, ABS, polyetherimide, liquid crystal polymer, and alumina ceramics is used. In addition to the one formed in a planar shape as shown in FIG.
A three-dimensionally formed one can be used. First, the surface of the insulating substrate 1 is coated with a chromic acid solution or KO.
By treating with H aqueous solution, phosphoric acid solution, etc.
As shown in (b), a roughening treatment for providing fine irregularities 11 is performed.

Next, FIG. 1 shows the entire surface of the insulating substrate 1.
The plating underlayer 2 is formed as shown in FIG. The plating base layer 2 can be formed by attaching a plating catalyst or a compound of the plating catalyst to the surface of the insulating substrate 1. In the embodiment of FIG. 1, Pd which is a catalyst for electroless plating is used. After the insulating substrate 1 is immersed in the contained solution, an activation treatment is performed, and Pd nucleation is performed on the surface of the insulating substrate 1 to form the plating base layer 2.

Next, the surface of the insulating substrate 1 is irradiated with an electromagnetic wave such as a laser, and a portion of the plating underlayer 2 where the electromagnetic wave is irradiated is irradiated.
Is removed. As the electromagnetic waves, X-rays, ultraviolet rays, and the like can be used in addition to lasers. Since lasers are most suitable, those using lasers as electromagnetic waves will be mainly described below. As this laser, for example, a Q-switched YAG laser can be used, and the laser is irradiated while moving to the surface of the insulating substrate 1 by operating with a galvanomirror or the like. The galvanometer mirror is a mirror formed to be variable in angle using a galvanometer, and can move a beam at a high speed and obtain a laser spot diameter of several tens of μm.
Laser irradiation is performed on the surface of the insulating substrate 1 by the circuit 5.
Is performed in a portion other than the circuit portion 3 where the circuit portion 3 is formed, that is, in the non-circuit portion 4 serving as an insulating space between the circuit portions 3. Move (scan) laser along pattern 4
By irradiating the substrate, the plating underlayer 2 in the boundary region between the non-circuit portion 4 and the circuit portion 3 is removed. Therefore, as shown in FIG. 1D, the plating underlayer 2 at the boundary with the circuit portion 3, which is the portion irradiated with the laser, is removed from the plating underlayer 2 of the non-circuit portion 4. The non-irradiated portion of the laser in the plating underlayer 2 is left without being removed together with the plating underlayer 2 of the circuit portion 3.
The irradiation energy of the laser is, for example, 10 to 300 μJ / p.
ulse is preferable, and the surface portion of the insulating base material 1 may be removed simultaneously with the plating base layer 2. Here, when the width of the non-circuit portion 4 (the width between the adjacent circuit portions 3) is equal to the spot diameter of the irradiation laser (for example, φ100 μm), the laser is irradiated once along the non-circuit portion 4. Thereby, the plating underlayer 2 in the boundary regions on both sides of the non-circuit portion 4 can be removed.

After irradiating the non-circuit portion 4 on the surface of the insulating substrate 1 with the laser to the boundary region with the circuit portion 3 as described above, the laser is applied to an electroless plating bath such as an electroless copper plating solution. By immersing the material 1 or the like, an electroless plating layer 12 of copper or the like is deposited to a thickness of about 10 μm on the plating base layer 2 remaining on the surface of the insulating substrate 1 without being irradiated with the laser.
By providing the electroless plating layer 12 on the plating base layer 2 of the circuit section 3 in this manner, the circuit
Can be formed. Electroless plating layer 1
2 is also provided on the plating underlayer 2 remaining in the non-circuit portion 4, but the boundary portion between the plating underlayer 2 of the circuit portion 3 and the plating underlayer 2 of the non-circuit portion 4 is removed by laser irradiation. Therefore, the insulation of the circuit 5 is ensured, and there is no particular problem in performance.

After the circuit is formed by plating the plating base layer 2 of the circuit portion 3 as described above, a solder resist, Ni plating, and Au plating are applied as necessary, thereby completing the circuit board. In manufacturing the circuit board as described above, the laser irradiation is performed only on the boundary region between the non-circuit portion 4 and the circuit portion 3 of the insulating base material 1, and the laser is applied to the entire surface of the non-circuit portion 4. It is not necessary to scan and irradiate, so that the laser irradiation processing time can be shortened as compared with the case where the laser is drawn and illuminated over the entire wide area of the non-circuit portion 4, and the productivity of the circuit board can be reduced. It is possible to increase. In the above embodiment, electroless plating is performed when forming a circuit by plating after laser irradiation. However, in addition to electroless plating, electroplating, CVD (chemical vapor deposition), PVD
The circuit can be formed using any plating means such as (physical vapor deposition).

[0016]

As described above, according to the present invention, a plating catalyst and a compound of a plating catalyst are attached to the surface of an insulating substrate to form a plating underlayer, and a circuit portion of the insulating substrate and a non-circuit By irradiating an electromagnetic wave such as a laser corresponding to the pattern of the non-circuit portion to the boundary region of the portion, after removing the plating underlayer of the irradiated portion irradiated with the electromagnetic wave such as the laser leaving the non-irradiated portion, Since plating is applied to the plating underlayer, it is sufficient that laser irradiation is performed on the boundary region between the circuit portion and the non-circuit portion. Compared with this, the laser irradiation processing time can be shortened, and the productivity of the circuit board can be increased.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, and (a) to (e) are perspective views.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating base material 2 Plating base layer 3 Circuit part 4 Non-circuit part 5 Circuit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshimitsu Nakamura 1048 Kadoma Kadoma, Osaka Pref. Matsushita Electric Works, Ltd. (72) Inventor Yoshiyuki Uchino 1048 Kadoma Kadoma, Kadoma, Osaka Pref. (72) Inventor Norio Kamada 1048 Kadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Works Co., Ltd. (72) Inventor Isuji Nakajima 1048 Kadoma Odoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Works Co., Ltd. 1048 Kadoma, Kamon, Fumonma-shi Matsushita Electric Works, Ltd.

Claims (1)

[Claims] 1. A plating catalyst and a compound of a plating catalyst are attached to a surface of an insulating substrate to form a plating underlayer.
By irradiating the boundary region between the circuit part and the non-circuit part of the insulating base material with an electromagnetic wave such as a laser corresponding to the pattern of the non-circuit part, the non-irradiated part is irradiated with the electromagnetic wave such as a laser while leaving the non-irradiated part. A method for manufacturing a circuit board, comprising: plating a plating base layer after removing a plating base layer in a portion.