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. 27, 2004
Filed:
Apr. 05, 2001
Junichi Mitani, Kawasaki, JP;
Makoto Yasuda, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The semiconductor device according to the present invention comprises: a semiconductor substrate of a first conductivity type; a well of a second conductivity type different from the first conductivity type formed in a region surrounding a region of the semiconductor substrate ; a diffused layer of the second conductivity type formed, buried in the semiconductor substrate in the region and connected to the well on a side thereof; and a well of the first conductivity type formed in the semiconductor substrate in the region on the side of a surface thereof and electrically isolated from a rest region of the semiconductor substrate by the well and the diffused layer . This constitution of the semiconductor device permits the diffused layer and the well to be formed by the use of one and the same mask, whereby in electrically isolating the well from the semiconductor substrate by the well and the diffused layer , the triple well can be formed without increasing lithography steps.