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:
Aug. 14, 2018
Filed:
Aug. 11, 2016
Fuji Electric Co., Ltd., Kawasaki, JP;
Tomonori Mizushima, Matsumoto, JP;
Yusuke Kobayashi, Matsumoto, JP;
FUJI ELECTRIC CO., LTD., Kawasaki, JP;
Abstract
A method of manufacturing a semiconductor device, where the device includes a donor layer that is obtained by changing a crystal defect formed in a first-conduction-type drift layer by proton radiation into a donor and in which the donor layer has an impurity concentration distribution including a first portion with a maximum impurity concentration and a second portion with a concentration gradient in which the impurity concentration is reduced from the first portion to both surfaces of the first-conduction-type drift layer. The method includes performing proton radiation for a first-conduction-type semiconductor substrate which will be the first-conduction-type drift layer to form a crystal defect in the first-conduction-type semiconductor substrate; and performing a heat treatment at a temperature equal to or higher than 300° C. and equal to or lower than 450° for one minute to 300 minutes to change the crystal defect into a donor.