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:
Sep. 20, 2011
Filed:
May. 01, 2009
Yasuhiro Takeda, Gifu, JP;
Seiji Otake, Saitama, JP;
Kazunori Fujita, Gifu, JP;
SANYO Semiconductor Co., Ltd., Gunma, JP;
Semiconductor Components Industries, LLC, Phoenix, AZ (US);
Abstract
An ON resistance of a trench gate type transistor and a withstand voltage of a planar type transistor are optimized at the same time. Each of first and second regions of a semiconductor layer is formed by epitaxial growth on each of first and second regions of a semiconductor substrate, respectively. A first buried layer is formed between the first region of the semiconductor substrate and the first region of the semiconductor layer, while a second buried layer is formed between the second region of the semiconductor substrate and the second region of the semiconductor layer. The first buried layer is formed of an Ntype first impurity-doped layer and an N type second impurity-doped layer that extends beyond the fist impurity-doped layer. The second buried layer is formed of an Ntype impurity-doped layer only. In the first region of the semiconductor layer, an impurity is diffused from a surface of the semiconductor layer deep into the semiconductor layer to form an N type third impurity-doped layer. The trench gate type transistor is formed in the first region of the semiconductor layer and the planar type transistor is formed in the second region of the semiconductor layer.