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:
Dec. 11, 2012
Filed:
Mar. 17, 2011
Tetsuro Nozu, Tokyo, JP;
Tetsuro Nozu, Tokyo, JP;
Kabushiki kaisha Toshiba, Tokyo, JP;
Abstract
In one embodiment, a bidirectional voltage-regulator diode includes first to fifth semiconductor layers formed on an inner surface of a first recess formed in a semiconductor substrate of an N-type in the order. The first semiconductor layer of the N-type has a first impurity concentration lower than an impurity concentration of the semiconductor substrate. The second semiconductor layer of a P-type has a second impurity concentration. The third semiconductor layer of the P-type has a third impurity concentration higher than the second impurity concentration. The fourth semiconductor layer of the P-type has a fourth impurity concentration lower than the third impurity concentration. The fifth semiconductor layer of the N-type has a fifth impurity concentration.