Hitachi Chemical Company, Ltd.

Kouichi Kaitou

Naoki Fukutomi

Yoshiaki Tsubomatsu

Hajime Nakayama

Itsuo Watanabe

Hidehiro Nakamura

Atsushi Kuwano

Masahiko Itabashi

Masanori Nakamura

Yasunobu Yoshidomi

The present invention provides a process for the fabrication of a wiring board, which comprises the following steps: (a) forming a first wiring pattern on a first side of a self-supporting carrier metal foil so as to obtain a self-supporting wiring sheet comprising the carrier metal foil and the first wiring pattern; (b) superposing and pressing the first side of said self-supporting wiring sheet on and against an insulating substrate so that the first wiring pattern is_embedded in the insulating substrate and constitutes a surface with the insulating substrate; and (c) etching off desired portions of said carrier metal foil to form a second wiring pattern made of said carrier metal foil remaining on the surface constituted by the insulating substrate and the first wiring pattern. The present invention also provides the wiring board for electrical tests so fabricated.

Process for the fabrication of wiring board for electrical tests

A wiring board for electrical tests; having an insulating substrate, wiring of predetermined pattern which is embedded in the insulating substrate, and bump electrodes which are formed on the wiring and which are respectively brought into contact with corresponding electrodes of an article to-be-tested. Thus, even when the electrode pitch of the article to-be-tested such as a semiconductor device has become smaller(for example, less than 0.1 [mm]), the electrodes can be formed so as to cope with the electrical tests of the article.

Wiring board for electrical tests with bumps having polymeric coating

A wiring board is fabricated through the following steps: (A) forming, on one side of an elongated carrier metal foil made of a first metal, a thin layer with a second metal whose etching conditions are different from those of the first metal; (B) forming, on a surface of the thin layer, a desired wiring pattern with a third metal whose etching conditions are different from those of the second metal; (C) superposing the carrier metal foil on an insulating substrate with the side of the wiring pattern being positioned inside, whereby the wiring pattern is embedded in the insulating substrate; and (D) etching off the carrier metal foil and the thin layer at desired parts thereof.

Fabrication process of wiring board

Growing community of inventors

Ibaraki-ken, Japan

Kouichi Kaitou