Fujitsu Corporation

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Tokyo Heat Treating Company, Ltd.

Kazuyoshi Fujita

Kunihiko Gotoh

Hiroshi Shimura

Akihiko Ito

Fumitaka Abukawa

Hitoshi Goi

Takeshi Yamamura

Yoshihisa Takayama

Keishichi Namba

Tadayoshi Juge

Yuichi Takasu

Nobuo Nishioka

Yoshiaki Shimizu

Gas carburizing method and apparatus

A programmable integrated circuit has multi-layer wiring with openings over fuses, and a fabrication method forms the openings for each fuse, to avoid damage due to the blowing off of the fuses. The forming of the openings is performed by etching each insulating layer on the fuses after it is formed over the pre-formed wiring-layers. This results in shorter etching time as compared to the prior art etching method where the openings are etched in all the layers for the whole depth in one process step. Because of the shorter time necessary for each etching, overetching and side-etching are reduced, thus providing the openings with more accurately determined dimensions, which provides higher yield for manufacturing the device. The contact holes and the windows for the bonding pads in each insulating layer are etched in the same fabrication step for forming the openings for the fuses in the same insulating layer. This requires no additional fabrication processes for the IC and results in no increase of the fabrication time and cost.

Method for fabricating an integrated circuit with multi-layer wiring

Growing community of inventors

Yokohama, Japan

Kazuyoshi Fujita