Patent Number: 7,786,553

Title: Method of fabricating semiconductor device

Abstract: Method of fabricating thin-film transistors in which contact with connecting electrodes becomes reliable. When contact holes are formed, the bottom insulating layer is subjected to a wet etching process, thus producing undercuttings inside the contact holes. In order to remove the undercuttings, a light etching process is carried out to widen the contact holes. Thus, tapering section are obtained, and the covering of connection wiring is improved.

Inventors: Zhang; Hongyong (Kanagawa, JP)

Assignee: Semiconductor Energy Laboratory Co., Ltd.

International Classification: H01L 23/58 (20060101); H01L 31/00 (20060101); H01L 21/33 (20060101); H01L 21/4763 (20060101)

Expiration Date: 8/31/12018