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:
Dec. 03, 2002
Filed:
Nov. 01, 1996
Chang-Ki Jeon, Kyungki-do, KR;
Young-Soo Jang, Kyungki-do, KR;
Fairchild Semiconductor Corporation, South Portland, ME (US);
Abstract
A trench DMOS device having improved breakdown characteristics. The trench DMOS device has a gate oxide layer which has a substantially flattened thick portion in the bottom of the trench and which is relatively thinner on the sidewalls. In greater detail, the trench DMOS device comprises a trench formed in a semiconductor substrate, said trench having sidewalls and a bottom, a gate polysilicon layer filled into said trench, and a gate oxide layer formed between said gate polysilicon layer and the sidewalls and bottom of said trench, wherein a bottom part of said gate oxide layer has a thickness greater than both sidewall parts thereof, and a central region of said bottom part is substantially flattened with a thickness greater than boundary regions thereof. Also disclosed is a novel method of fabricating a trench DMOS device.