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:
Jun. 03, 2016
Fuji Electric Co., Ltd., Kawasaki-shi, JP;
Masayuki Miyazaki, Matsumoto, JP;
Takashi Yoshimura, Matsumoto, JP;
Hiroshi Takishita, Matsumoto, JP;
Hidenao Kuribayashi, Matsumoto, JP;
FUJI ELECTRIC CO., LTD., Kawasaki-Shi, JP;
Abstract
A pcollector layer is provided in a rear surface of a semiconductor substrate which will be an ndrift layer and an nfield stop layer is provided in a region which is deeper than the pcollector layer formed on the rear surface side. A front surface element structure is formed on the front surface of the semiconductor substrate and then protons are radiated to the rear surface of the semiconductor substrate at an acceleration voltage corresponding to the depth at which the nfield stop layer is formed. A first annealing process is performed at an annealing temperature corresponding to the proton irradiation to change the protons into donors, thereby forming a field stop layer. Then, annealing is performed using annealing conditions suitable for the conditions of a plurality of proton irradiation processes to recover each crystal defect formed by each proton irradiation process.