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:
Oct. 20, 2009
Filed:
Jul. 25, 2007
Yong-cheol Choi, Siheung, KR;
Chang-ki Jeon, Kimpo, KR;
Cheol-joong Kim, Boocheon, KR;
Fairchild Korea Semiconductor Ltd., Kyungki-do, KR;
Abstract
A method of forming a metal oxide semiconductor (MOS) transistor includes the following steps. A substrate of a first conductivity is provided. A first buried layer of a second conductivity type is formed over the substrate. A second buried layer of the first conductivity type is formed in the first buried layer. An epitaxial layer of the second conductivity type is formed over the substrate. A drift region of a second conductivity type is formed in the epitaxial layer. A gate layer is formed over the drift region. A body region of the first conductivity type is formed in the drift region such that the gate overlaps a surface portion of the body region. A source region of the second conductivity is formed in the body region. A drain region of the second conductivity type is formed in the drift region. The drain region is laterally spaced from the body region. The first and second buried layers laterally extend from under the body region to under the drain region. The surface portion of the body region extends between the source region and the drift region to form a channel region of the transistor.