Kabushiki Kaisha Toshiba

Masaaki Iwanishi

Kenji Suzuki

Toshihisa Inoue

Shinjiro Yano

Kazuhiko Kurahashi

Semiconductor element

A semiconductor device includes a metal film, not in ohmic contact with a guard ring region (a second region). The metal film is formed on that surface portion of an insulating film under which the guard ring region is formed to surround a base region (a first region) of a planar transistor. In this arrangement, a planar semiconductor device with a high withstand voltage, which is free of short-circuiting between electrodes upon the measurement of the withstand voltage and involves no degeneration of the withstand voltage resulting from an atmospheric humidity, can be obtained. The metal film, which is not in contact with the guard ring region, is 'electrically floated', i.e., is not in contact with any area inclusive of the guard ring region.

Growing community of inventors

Himeji, Japan

Masaaki Iwanishi