JPH05235499A - Circuit board and its manufacture - Google Patents
Circuit board and its manufactureInfo
- Publication number
- JPH05235499A JPH05235499A JP7281292A JP7281292A JPH05235499A JP H05235499 A JPH05235499 A JP H05235499A JP 7281292 A JP7281292 A JP 7281292A JP 7281292 A JP7281292 A JP 7281292A JP H05235499 A JPH05235499 A JP H05235499A
- Authority
- JP
- Japan
- Prior art keywords
- hole
- circuit board
- conductor
- substrate
- slit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/11—Printed elements for providing electric connections to or between printed circuits
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
- H05K3/4038—Through-connections; Vertical interconnect access [VIA] connections
Landscapes
- Printing Elements For Providing Electric Connections Between Printed Circuits (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、スルーホールによって
表裏の導通が取られている厚膜回路基板およびその製造
方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thick film circuit board whose front and back sides are electrically connected by through holes and a method for manufacturing the same.
【０００２】[0002]
【従来の技術】一般に、厚膜回路基板における表裏の導
通はスルーホールによって行われており、この表裏導通
用スルーホールを有する回路基板は次のような方法で製
造されていた。まず、96％Ａｌ2 Ｏ3 基板３の一方の主
面上の所定位置において、レーザービームを円形状に複
数回照射して円筒状のスルーホール１を形成する。次い
で、スクリーン印刷法等により、基板３の表面に所定の
回路パターンが構成されるように導電ペーストを塗布す
ると共に、スルーホール１の内壁にも導電ペーストを塗
布し、これを乾燥および焼成することによって導体２を
形成する（図１５）。なお、図１５（ａ）は回路基板に
おけるスルーホール近辺を拡大した上面図であり、図１
５（ｂ）は、同図（ａ）に示す基板を図中の一点鎖線で
切断し、その断面を示す図である。2. Description of the Related Art Generally, a thick film circuit board is electrically connected to the front and back by through holes, and a circuit board having the through holes for conducting the front and back has been manufactured by the following method. First, at a predetermined position on one main surface of the 96% Al 2 O 3 substrate 3, a laser beam is irradiated in a circular shape multiple times to form a cylindrical through hole 1. Then, by a screen printing method or the like, a conductive paste is applied to the surface of the substrate 3 so that a predetermined circuit pattern is formed, and an inner wall of the through hole 1 is also applied with the conductive paste, which is dried and baked. To form the conductor 2 (FIG. 15). Note that FIG. 15A is an enlarged top view of the vicinity of the through hole in the circuit board.
5 (b) is a diagram showing a cross section of the substrate shown in FIG. 5 (a), taken along the chain line in the figure.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、上記従
来の回路基板は、図１５（ｂ）からもわかるように、基
板主面とスルーホール内壁面との境界であるエッジにお
ける導体２の膜厚が、他の部位における導体２の膜厚
（基板表面の導体の膜厚など）よりも著しく薄くなり、
基板表裏の導体抵抗値が上昇してしまうという問題点が
あった。However, in the above-mentioned conventional circuit board, as can be seen from FIG. 15B, the film thickness of the conductor 2 at the edge which is the boundary between the main surface of the board and the inner wall surface of the through hole is small. , Is significantly thinner than the film thickness of the conductor 2 in other parts (such as the film thickness of the conductor on the substrate surface),
There is a problem that the conductor resistance value on the front and back of the substrate increases.
【０００４】そこで、従来の技術においては、図１６に
示すように、回路を構成するそれぞれの導体パターンに
複数個のスルーホール１を形成したり、スルーホール内
部に導体を充填することにより、基板表裏の導体抵抗値
の低減化を図っていた。しかしながら、１つの導体パタ
ーンに複数個のスルーホールを形成するには、導体パタ
ーンの面積を拡大する必要があるため、回路基板の縮小
や電子部品の高集積が行えないという問題点があった。
また、スルーホール内部への導電ペーストの充填の場
合、スルーホール内部に空間が生じてしまい表裏導通が
取れなくなることが多く、歩留まりが著しく低下してし
まうという問題点があった。Therefore, in the conventional technique, as shown in FIG. 16, a plurality of through holes 1 are formed in each conductor pattern forming a circuit, or a conductor is filled in the through holes to form a substrate. The conductor resistance of the front and back was reduced. However, in order to form a plurality of through holes in one conductor pattern, it is necessary to enlarge the area of the conductor pattern, which causes a problem that the circuit board cannot be downsized and electronic components cannot be highly integrated.
Further, in the case of filling the inside of the through hole with the conductive paste, there is a problem in that a space is often generated inside the through hole and front-to-back conduction is often lost, resulting in a significant decrease in yield.
【０００５】そこで本発明は、上述従来の技術の問題点
を解決し、基板の縮小や電子部品の高集積を行うことが
できる回路基板およびその製造方法を提供することを目
的とする。SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a circuit board and a method of manufacturing the same which solve the above-mentioned problems of the prior art and can reduce the size of the board and highly integrate electronic components.
【０００６】[0006]
【課題を解決するための手段】本発明者は、上記目的を
達成するために鋭意研究の結果、回路基板における表裏
導通を取るためのスルーホールの形状を、開口部がＣ字
型をしたスリット状とし、スルーホール内部に隙間なく
導体を充填することにより、上記課題が解決されること
を見い出し、本発明に到達した。As a result of earnest research for achieving the above-mentioned object, the present inventor has found that the through-hole has a C-shaped slit for the shape of the through-hole for conducting the front and back of the circuit board. It was found that the above problems can be solved by filling the inside of the through hole with a conductor without leaving a gap, and arrived at the present invention.
【０００７】すなわち、本発明は、表裏導電接続のため
のスルーホールがスリット状に形成され、前記スルーホ
ール内部に隙間なく導体が充填されていることを特徴と
する回路基板；および基板の一方の主面からレーザービ
ームを円形状に照射して行き、レーザービームの軌跡が
１周する前にビーム照射を止めることにより、基板表面
における開口形状がＣ字型をしたスリット状のスルーホ
ールを形成し、この基板の表面に所定の回路導体パター
ンを形成すると共に、スルーホール内部に隙間なく導体
を充填することを特徴とする回路基板の製造方法を提供
するものである。That is, the present invention is characterized in that through holes for front and back conductive connection are formed in a slit shape, and conductors are filled in the through holes without a gap; and one of the boards. By irradiating the laser beam in a circular shape from the main surface and stopping the beam irradiation before the laser beam traverses once, a slit-shaped through hole with a C-shaped opening on the substrate surface is formed. The present invention provides a method for manufacturing a circuit board, characterized in that a predetermined circuit conductor pattern is formed on the surface of this board, and conductors are filled in the through holes without any gaps.
【０００８】[0008]
【作用】本発明の回路基板における表裏導通を取るため
のスリット状のスルーホールとは、基板表面において細
い溝状に開口している溝穴であって、その形状は、小さ
なランド上でも容易に形成することができるようにあま
り複雑ではなく、また基板表面とスルーホール内壁面と
の境界であるエッジの長さが長く、さらにスリット状の
スルーホールのスリット幅が70μｍ程度の狭小なものが
良い。例えば、図１に示すように基板３の表面における
開口部の形状がＣ字型をしているものや、図２ないし１
４にあげるような形状の開口部を有するものなどが考え
られる。In the circuit board of the present invention, the slit-shaped through hole for providing conduction between the front and back is a slot opening in the shape of a thin groove on the surface of the board, and the shape thereof is easy even on a small land. It is not so complicated that it can be formed, the length of the edge that is the boundary between the substrate surface and the inner wall surface of the through hole is long, and the slit width of the slit-like through hole is as narrow as about 70 μm. .. For example, as shown in FIG. 1, the shape of the opening on the surface of the substrate 3 is C-shaped, and FIG.
One having an opening having a shape as shown in 4 is conceivable.
【０００９】基板に形成するスルーホールを上記のよう
にエッジの長いスリット状とすることにより、導体を確
実にスルーホール内部に隙間なく充填することができる
ようになる。このように、エッジの長いスリット状のス
ルーホール内部に導体を隙間なく充填することにより、
スルーホール内における導体と基板表面における導体と
の接触面積が、円筒状のスルーホールの内壁面にのみ導
体を形成していた従来の回路基板と同等となる上、エッ
ジにおいて導体の膜厚が薄くなることがなくなる。その
ため、基板表裏の導体抵抗値の上昇、およびエッジにお
いて発生する絶縁（エッジ切れ）が防止されるようにな
る。By forming the through hole formed in the substrate in the form of a slit having a long edge as described above, it becomes possible to reliably fill the inside of the through hole with a conductor. In this way, by filling the inside of the slit-shaped through hole with a long edge with a conductor without gaps,
The contact area between the conductor in the through hole and the conductor on the surface of the board is the same as that of the conventional circuit board in which the conductor is formed only on the inner wall surface of the cylindrical through hole, and the thickness of the conductor is thin at the edge. Will never become. Therefore, the increase of the conductor resistance value on the front and back of the substrate and the insulation generated at the edge (cutting of the edge) can be prevented.
【００１０】また、本発明の回路基板におけるＣ字型の
スリット状のスルーホールは、レーザービームを円形状
に照射して行き、レーザービームの軌跡が１周する前に
ビーム照射を止めることにより形成することができる。
これは、従来の円筒状のスルーホール形成工程における
レーザー照射プログラムを変えるだけですむため、スル
ーホール加工時間が30％程度削減できるようになる。Further, the C-shaped slit-shaped through hole in the circuit board of the present invention is formed by irradiating the laser beam in a circular shape and stopping the beam irradiation before the track of the laser beam makes one round. can do.
This requires only changing the laser irradiation program in the conventional cylindrical through-hole forming process, so that the through-hole processing time can be reduced by about 30%.
【００１１】以下、実施例により本発明をさらに詳細に
説明する。しかし本発明の範囲は以下の実施例により制
限されるものではない。Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by the following examples.
【００１２】[0012]
【実施例】本発明の一実施例として、基板表面における
開口部の形状がＣ字型をしたスルーホールを有する回路
基板の製造方法を以下に示す。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a method for manufacturing a circuit board having a through hole having a C-shaped opening on the surface of the board will be described below.
【００１３】まず、96％Ａｌ2 Ｏ3 基板３にレーザース
クライブ加工によって基板主面上から見た形状がＣ字型
をしたスリット状のスルーホール１を形成した。なお、
スルーホール１を形成する際におけるレーザービームの
照射は、円周の３／４でレーザービームの照射が止まる
ようにプログラムを変更したこと以外は従来の円筒状の
スルーホールを形成する場合と同様にして行った。ま
た、Ｃ字型のスリット状のスルーホール１は、Ｃ字の外
周の直径が 300μｍ、スリットの幅が70μｍ、円周の75
％が空間部であり、エッジの長さは従来の円筒状のスル
ーホールの約 1.5倍である。First, a slit-shaped through hole 1 having a C-shape when viewed from the main surface of the substrate was formed on a 96% Al 2 O 3 substrate 3 by laser scribing. In addition,
The irradiation of the laser beam when forming the through hole 1 is the same as the case of forming the conventional cylindrical through hole except that the program is changed so that the irradiation of the laser beam stops at 3/4 of the circumference. I went. The C-shaped slit-shaped through hole 1 has a C-shaped outer diameter of 300 μm, a slit width of 70 μm, and a circular circumference of 75 μm.
% Is a space, and the length of the edge is about 1.5 times that of a conventional cylindrical through hole.
【００１４】次に、上記スルーホール１を形成した基板
３の表面に、スクリーン印刷法によってＣｕ系厚膜導体
ペーストを所定の回路パターンが構成されるように塗布
すると共に、スルーホール１内部に該ペーストを充填
し、これを乾燥および焼成して導体２を形成した（図
１）。Next, a Cu-based thick film conductor paste is applied to the surface of the substrate 3 on which the through hole 1 is formed by screen printing so that a predetermined circuit pattern is formed, and the inside of the through hole 1 is coated with the Cu thick film conductor paste. The paste was filled, and the paste was dried and fired to form the conductor 2 (FIG. 1).
【００１５】上記のようにして多数の回路基板を作製
し、その中から無作為に20個を選び、基板表裏の導体抵
抗値の測定を行った。その結果、20個の回路基板の表裏
の導体抵抗値の平均は30ｍΩであり、基板表裏の導体抵
抗値の上昇は認められなかった。A large number of circuit boards were prepared as described above, and 20 pieces were randomly selected from the circuit boards to measure the conductor resistance values on the front and back of the boards. As a result, the average of the conductor resistance values on the front and back sides of 20 circuit boards was 30 mΩ, and no increase in the conductor resistance values on the front and back sides of the boards was observed.
【００１６】[0016]
【比較例】本発明の回路基板との比較のため、円筒状の
スルーホールを有する従来の回路基板を作製し、基板表
裏の導体抵抗値の測定を行った。[Comparative Example] For comparison with the circuit board of the present invention, a conventional circuit board having a cylindrical through hole was prepared, and the conductor resistance values on the front and back of the board were measured.
【００１７】まず、96％Ａｌ2 Ｏ3 基板にレーザースク
ライブ加工によって開口部の直径が300μｍの円筒状の
スルーホールを形成した。次に、スルーホールを形成し
た基板の表面に、スクリーン印刷法によってＣｕ系厚膜
導体ペーストを所定の回路パターンが構成されるように
塗布すると共に、スルーホール内壁に該ペーストを塗布
し、これを乾燥および焼成して導体２を形成した。First, a cylindrical through hole having an opening diameter of 300 μm was formed on a 96% Al 2 O 3 substrate by laser scribing. Next, a Cu-based thick film conductor paste is applied by a screen printing method so that a predetermined circuit pattern is formed on the surface of the substrate in which the through holes are formed, and the paste is applied to the inner walls of the through holes. The conductor 2 was formed by drying and firing.
【００１８】上記のようにして多数の回路基板を作製
し、その中から無作為に20個を選び、基板表裏の導体抵
抗値の測定を行った。その結果、20個の回路基板の表裏
の導体抵抗値の平均は50ｍΩであり、基板表裏の導体抵
抗値の上昇が認められた。A large number of circuit boards were prepared as described above, and 20 pieces were randomly selected from the circuit boards to measure the conductor resistance values on the front and back of the boards. As a result, the average of the conductor resistance values on the front and back sides of the 20 circuit boards was 50 mΩ, and an increase in the conductor resistance values on the front and back sides of the boards was recognized.
【００１９】[0019]
【発明の効果】本発明の回路基板は、スルーホールの形
状を改良することによって基板表裏の導体抵抗値の上昇
を防止したため、１つの導体パターンに複数のスルーホ
ールを形成する必要がなくなり、回路基板の縮小や電子
部品の高集積が可能になった。また、本発明の回路基板
は、スルーホール内部に導体を隙間なく充填しているた
め、エッジ切れによる基板表裏絶縁が防止されるように
なった。さらに、本発明の回路基板の製造方法による
と、スルーホール加工時間が30％程度削減できるように
なる。In the circuit board of the present invention, the shape of the through hole is improved to prevent the increase of the conductor resistance value on the front and back sides of the board. Therefore, it is not necessary to form a plurality of through holes in one conductor pattern, and the circuit Substrate reduction and high integration of electronic components are now possible. Further, in the circuit board of the present invention, since the conductor is filled in the through hole without any gap, the insulation of the board from the front and the back due to the edge breakage is prevented. Further, according to the method for manufacturing a circuit board of the present invention, the through hole processing time can be reduced by about 30%.
【図１】本発明の回路基板の一例を示す図であって、
（ａ）はスルーホール近辺を拡大した上面図、（ｂ）は
（ａ）の基板を一点鎖線で切断し、その断面を示す図で
ある。FIG. 1 is a diagram showing an example of a circuit board of the present invention,
(A) is an enlarged top view of the vicinity of the through hole, and (b) is a view showing a cross section of the substrate of (a) taken along a chain line.
【図２】本発明の回路基板の別の一例を示す図であっ
て、スルーホール近辺を拡大した上面図である。FIG. 2 is a view showing another example of the circuit board of the present invention, and is an enlarged top view of the vicinity of the through hole.
【図３】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 3 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図４】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 4 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図５】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 5 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図６】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 6 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図７】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 7 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図８】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 8 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図９】本発明の回路基板のさらに別の一例を示す図で
あって、スルーホール近辺を拡大した上面図である。FIG. 9 is a diagram showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図１０】本発明の回路基板のさらに別の一例を示す図
であって、スルーホール近辺を拡大した上面図である。FIG. 10 is a view showing still another example of the circuit board of the present invention, and is an enlarged top view of the vicinity of the through hole.
【図１１】本発明の回路基板のさらに別の一例を示す図
であって、スルーホール近辺を拡大した上面図である。FIG. 11 is a view showing still another example of the circuit board of the present invention, and is an enlarged top view of the vicinity of the through hole.
【図１２】本発明の回路基板のさらに別の一例を示す図
であって、スルーホール近辺を拡大した上面図である。FIG. 12 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図１３】本発明の回路基板のさらに別の一例を示す図
であって、スルーホール近辺を拡大した上面図である。FIG. 13 is a view showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図１４】本発明の回路基板のさらに別の一例を示す図
であって、スルーホール近辺を拡大した上面図である。FIG. 14 is a diagram showing still another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
【図１５】従来の回路基板の一例を示す図であって、
（ａ）はスルーホール近辺を拡大した上面図、（ｂ）は
（ａ）の基板を一点鎖線で切断し、その断面を示す図で
ある。FIG. 15 is a diagram showing an example of a conventional circuit board,
(A) is an enlarged top view of the vicinity of the through hole, and (b) is a view showing a cross section of the substrate of (a) taken along a chain line.
【図１６】本発明の回路基板の別の一例を示す図であっ
て、スルーホール近辺を拡大した上面図である。FIG. 16 is a diagram showing another example of the circuit board of the present invention, which is an enlarged top view of the vicinity of the through hole.
１‥‥‥スルーホール ２‥‥‥導体 ３‥‥‥基板 1 through hole 2 conductor 3 substrate
Claims (2)
リット状に形成され、前記スルーホール内部に隙間なく
導体が充填されていることを特徴とする回路基板。1. A circuit board, wherein through holes for front and back conductive connection are formed in a slit shape, and conductors are filled in the through holes without any gaps.
円形状に照射して行き、レーザービームの軌跡が１周す
る前にビーム照射を止めることにより、基板表面におけ
る開口形状がＣ字型をしたスリット状のスルーホールを
形成し、この基板の表面に所定の回路導体パターンを形
成すると共に、スルーホール内部に隙間なく導体を充填
することを特徴とする回路基板の製造方法。2. A laser beam is radiated in a circular shape from one main surface of the substrate, and the beam irradiation is stopped before the trajectory of the laser beam makes one round, whereby a C-shaped opening is formed on the surface of the substrate. Forming a slit-shaped through hole, forming a predetermined circuit conductor pattern on the surface of the substrate, and filling the inside of the through hole with a conductor without a gap.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7281292A JPH05235499A (en) | 1992-02-24 | 1992-02-24 | Circuit board and its manufacture |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7281292A JPH05235499A (en) | 1992-02-24 | 1992-02-24 | Circuit board and its manufacture |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05235499A true JPH05235499A (en) | 1993-09-10 |
Family
ID=13500197
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7281292A Withdrawn JPH05235499A (en) | 1992-02-24 | 1992-02-24 | Circuit board and its manufacture |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05235499A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002091811A3 (en) * | 2001-05-09 | 2004-04-29 | Giesecke & Devrient Gmbh | Throughplating of flexible printed boards |
-
1992
- 1992-02-24 JP JP7281292A patent/JPH05235499A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002091811A3 (en) * | 2001-05-09 | 2004-04-29 | Giesecke & Devrient Gmbh | Throughplating of flexible printed boards |
| US7000845B2 (en) | 2001-05-09 | 2006-02-21 | Giesecke & Devrient Gmbh | Throughplating of flexible printed boards |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3568312A (en) | Method of making printed circuit boards | |
| US5010448A (en) | Printed circuit board | |
| JPH04793A (en) | Connecting method of electromagnetic wave shielding layer to ground circuit for printed circuit board | |
| US5293004A (en) | Printed circuit board having an electromagnetic shielding layer | |
| JPH05235499A (en) | Circuit board and its manufacture | |
| US5210379A (en) | Printed wiring board with electromagnetic wave shielding layer | |
| JP2000124561A (en) | Printed wiring board | |
| JPS55138864A (en) | Method of fabricating semiconductor assembling substrate | |
| JPH04273410A (en) | Wiring board and its manufacture | |
| JPH0747897Y2 (en) | Printed board | |
| JP3961997B2 (en) | High frequency printed circuit board | |
| JPH1051094A (en) | Printed wiring board, and its manufacture | |
| JPH04139783A (en) | Flexible circuit board for ic mounting and its manufacture | |
| JP7114509B2 (en) | wiring board | |
| JPS6011655Y2 (en) | printed board | |
| JPH09232716A (en) | Current capacity increasing method for printed board | |
| JPH01185912A (en) | Capacitor array | |
| JP2681205B2 (en) | Printed wiring board with membrane element | |
| JP2000049526A (en) | Dielectric plane antenna | |
| JPH08222823A (en) | Through hole wiring board | |
| JP2004023082A (en) | Printed circuit board | |
| JPH02177494A (en) | Printed wiring board | |
| JPH06188563A (en) | Manufacture of printed wiring board | |
| JPH0955580A (en) | Printed wiring board | |
| JPH0778904A (en) | Manufacture of printed wiring board |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 19990518 |