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. 03, 2019
Filed:
Jun. 16, 2015
Mitsubishi Electric Corporation, Tokyo, JP;
Yusuke Kawase, Tokyo, JP;
Mitsubishi Electric Corporation, Tokyo, JP;
Abstract
A method for manufacturing a semiconductor device includes the steps of forming a layer of a second conductivity type on a top-surface side of a substrate of a first conductivity type, and forming a buffer layer by performing a plurality of ion implantation steps, each of the ion implantation steps implanting ions of an impurity of the first conductivity type into a bottom-surface side of the substrate with an ion implantation angle with respect to a bottom surface of the substrate fixed, the ion implantation angle of a subsequent one of the ion implantation steps being smaller than that of the previous ion implantation step, wherein in the buffer layer formation step, the plurality of ion implantation steps is performed at a fixed acceleration energy.