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:
Mar. 08, 2005
Filed:
Dec. 26, 2002
Satoru Kaneko, Kumagaya, JP;
Toshiyuki Ohkoda, Oizumi-machi, JP;
Takao Myono, Menuma-machi, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
A latch up in a charge pump device is prevented as well as a withstand voltage of an MOS transistor used in the charge pump device is increased with this invention. A first and a second N-type epitaxial silicon layers are stacked on a P-type single crystalline silicon substrate, and P-type well regions are formed in the second epitaxial silicon layer separated from each other. A P-type isolation layer is formed between the P-type well regions. A P+-type buried layer is formed abutting on a bottom of each of the well regions, an N+-type buried layer is formed abutting on a bottom of the P+-type buried layer, and a transistor for charge transfer is formed in each of the P-type well regions.