The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 18, 1992
Filed:
Oct. 31, 1990
Iwao Hayase, Itami, JP;
Takuji Sonoda, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device includes a relatively broad recess in a semiconductor substrate between a source electrode and a drain electrode, a relatively narrow, deeper recess closer to the source electrode than to the drain electrode, and a T-shaped gate electrode having a broad head disposed in the narrower recess. A production method for a semiconductor device having a T-shaped gate electrode provided with a broad head and disposed in a two stage recess includes producing a relatively broad recess in a semiconductor substrate leaving a dummy gate, producing a resist pattern for producing the head of the T-shaped gate electrode, exposing the dummy gate by removing some of the resist pattern, and thereafter producing a narrower, deeper recess closer to the source electrode than to the drain electrode, thereby producing a two stage recess structure and producing a T-shaped gate electrode in the deeper recess.