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:
Jun. 30, 2015
Filed:
May. 21, 2014
Fuji Electric Co., Ltd., Kawasaki-shi, JP;
Michio Nemoto, Higashi-Chikuma-gun, JP;
Takashi Yoshimura, Matsumoto, JP;
FUJI ELECTRIC CO., LTD., , JP;
Abstract
A p anode layer () is formed on one main surface of an ndrift layer (). An ncathode layer () having an impurity concentration more than that of the ndrift layer () is formed on the other main surface of the ndrift layer (). An anode electrode () is formed on the surface of the p anode layer (). A cathode electrode () is formed on the surface of the ncathode layer (). An n-type broad buffer region () that has a net doping concentration more than the bulk impurity concentration of a wafer and less than that of the ncathode layer () and the p anode layer () is formed in the ndrift layer (). The resistivity ρof the ndrift layer () satisfies 0.12V≦ρ≦0.25Vwith respect to a rated voltage V. The total amount of the net doping concentration of the broad buffer region () is equal to or more than 4.8×10atoms/cmand equal to or less than 1.0×10atoms/cm.