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:
Jul. 19, 2011
Filed:
Aug. 31, 2007
Koichi Hashimoto, Hyogo, JP;
Shin Hashimoto, Osaka, JP;
Kyoko Egashira, Kyoto, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A production method for a semiconductor device includes providing a semiconductor substrate having semiconductor layer of a first conductivity type formed on a surface thereof; forming a first mask so as to cover a predetermined region of the semiconductor layer; (c) forming a well region of a second conductivity type by implanting impurity ions of the second conductivity type into the semiconductor layer having the first mask formed thereon; reducing the thickness of the first mask by removing a portion of the first mask; forming a second mask covering a portion of the well region by using photolithography; and forming a source region of the first conductivity type by implanting impurity ions of the first conductivity type into the semiconductor layer having the first mask with the reduced thickness and the second mask formed thereon.