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. 28, 2001
Filed:
May. 08, 1997
Koon Chong So, San Jose, CA (US);
Fwu-Iuan Hshieh, Saratoga, CA (US);
MegaMOS Corporation, San Jose, CA (US);
Abstract
The present invention discloses a DMOS transistor cell, supported on a substrate of a first conductivity type. The DMOS transistor cell includes a body region of a second conductivity type disposed in the substrate defining a central portion of the cell. This DMOS transistor cell further includes a trench gate filled with polysilicon therein surrounding the body region and defining a boundary of the cell. This DMOS transistor cell further includes a source of the first conductivity type defined by a narrow strip of source region disposed in the body region along an edge thereof adjacent to the trench gate. This transistor cell further includes a source contact defined by a cross-shaped trench filled with polysilicon disposed in the body region and a trench edge source extension extending laterally between the narrow strip of source region and in electric contact thereto for providing area for electrically connecting to a source contact to be formed thereon whereby the source contact can be more conveniently manufactured provided with reliable good contact to the narrow strip of source region while achieving cost savings without requiring the use of a source mask.