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. 02, 2008
Filed:
Aug. 02, 2005
Atsuko Yamashita, Yokosuka, JP;
Tetsuo Matsuda, Yokohama, JP;
Hideki Okumura, Ibo-gun, JP;
Masanobu Tsuchitani, Kawasaki, JP;
Atsuko Yamashita, Yokosuka, JP;
Tetsuo Matsuda, Yokohama, JP;
Hideki Okumura, Ibo-gun, JP;
Masanobu Tsuchitani, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A first semiconductor pillar layer of a first conductivity type is formed on a main surface of a semiconductor substrate of the first conductivity type. A second semiconductor pillar layer of a second conductivity type is formed adjacent to the first semiconductor pillar layer. A third semiconductor pillar layer of the first conductivity type is formed adjacent to the second semiconductor pillar layer. A semiconductor base layer of the second conductivity type is formed on the main surface of the second semiconductor pillar layer. An insulated-gate type semiconductor element is formed in the semiconductor base layer. The carrier concentration on the side of a main surface of each of said first through third semiconductor pillar layers is higher than a carrier concentration on the opposite side of said main surface in each of said first through third semiconductor pillar layers.