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:
May. 09, 2017
Filed:
Jan. 13, 2015
Renesas Electronics Corporation, Kawasaki-shi, JP;
Masaki Hama, Kawasaki, JP;
Yasuaki Kagotoshi, Kawasaki, JP;
RENESAS ELECTRONICS CORPORATION, Kawasaki-Shi, Kanagawa, JP;
Abstract
To form a MOSFET over a silicon carbide substrate, when a heat treatment accompanied by nitration is carried out to reduce the interface state density in the vicinity of the boundary between a gate insulating film and a silicon carbide substrate, CV hysteresis occurs due to the relationship between the capacitance and gate voltage of the MOSFET, thereby reducing the reliability of a semiconductor device. To solve the above problem, a heat treatment accompanied by nitration is carried out on the insulating film formed over the silicon carbide substrate (step S). Then, the insulating film is heated in an inert gas atmosphere (step S). Thereafter, a field effect transistor having a gate insulating film which is composed of the insulating film is formed over the silicon carbide substrate.