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:
Oct. 13, 2009
Filed:
Mar. 14, 2006
Naoki Kumagai, Tokyo, JP;
Hiroshi Kanemaru, Miyazaki, JP;
Yuiichi Harada, Nagano, JP;
Yoshihiro Ikura, Nagano, JP;
Ryuu Saitou, Nagano, JP;
Naoki Kumagai, Tokyo, JP;
Hiroshi Kanemaru, Miyazaki, JP;
Yuiichi Harada, Nagano, JP;
Yoshihiro Ikura, Nagano, JP;
Ryuu Saitou, Nagano, JP;
Abstract
To prevent the destruction of a semiconductor element due to negative resistance, and to reduce the dynamic resistance of a static electricity prevention diode, the ratio of the maximum electric field intensity during an avalanche and the average electric field in a strong electric field region, as well as the impurity density gradient in the vicinity of the strong electric field region are optimized. During avalanche breakdown, a depletion layer is formed across the entire high resistivity region, and its average electric field is kept to ½ or more of the maximum electric field intensity. The density gradients (the depths and impurity densities) of a pregion and of an nregion that form a p-n junction of the diode are controlled so that the density gradient in the neighborhood of the high resistivity region does not have negative resistance with respect to increase of the avalanche current.