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:
Apr. 16, 2002
Filed:
Mar. 28, 1997
Applicant:
Inventors:
Yukio Maki, Tokyo, JP;
Hiroki Honda, Tokyo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ;
U.S. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ;
Abstract
In a MOS semiconductor device including a normal MOS transistor and an output MOS transistor for an input/output buffer, the normal MOS transistor is formed in a normal well. In an output MOS transistor, the channel region of the second MOS transistor and an element isolation region are formed in the region of a higher impurity concentration. On the other hand, the source and drain regions are formed in a lower impurity concentration region. Thereby, the source/drain capacitance of the output MOS transistor may be reduced, and the input/output capacitance of the semiconductor device may be reduced.