Hitachi Chemical Company, Ltd.

Masahiko Itabashi

Naoki Fukutomi

Yoshiaki Tsubomatsu

Itsuo Watanabe

Hidehiro Nakamura

Atsushi Kuwano

Hajime Nakayama

Kouichi Kaitou

Masanori Nakamura

Toshio Yamazaki

Takeshi Yoshida

Hirohito Ohhata

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

The object of the present invention is to provide a wiring board fabrication process which is, not only so smooth on the surface that a fine wiring pattern can be formed thereon, but also suitable for mounting electronic parts having fine pitch terminals. The present invention is a fabrication process of a wiring board which comprises a wiring conductive line embedded in the surface of an insulating substrate so that the upper face of the conductive line and the surface of the substrate are flat, and a through-hole land which is a conductive portion projected from the surface of the substrate in a through-hole portion, which is characterized in removing the conductive portion projected from the surface of the substrate in the through-hole portion so as to have a flat surface on the surface of the substrate.

Fabrication process of wiring board

An insulating film formed by a plasma CVD method at the substrate temperature of 350.degree. to 550.degree. C.l is good in electric properties and heat resistance without causing whitening phenomenon is suitable for use in a thin-film electroluminescent device.

Process for forming insulating film used in thin film electroluminescent

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Mitsukaido, Japan

Masahiko Itabashi