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. 17, 2013
Filed:
Nov. 07, 2011
Ryosuke Kubota, Osaka, JP;
Keiji Wada, Osaka, JP;
Takeyoshi Masuda, Osaka, JP;
Hiromu Shiomi, Osaka, JP;
Ryosuke Kubota, Osaka, JP;
Keiji Wada, Osaka, JP;
Takeyoshi Masuda, Osaka, JP;
Hiromu Shiomi, Osaka, JP;
Sumitomo Electric Industries, Ltd., Osaka-Shi, JP;
Abstract
A silicon carbide substrate having a surface is prepared. An impurity region is formed by implanting ions from the surface into the silicon carbide substrate. Annealing for activating the impurity region is performed. The annealing includes the step of applying first laser light having a first wavelength to the surface of the silicon carbide substrate, and the step of applying second laser light having a second wavelength to the surface of the silicon carbide substrate. The silicon carbide substrate has first and second extinction coefficients at the first and second wavelengths, respectively. A ratio of the first extinction coefficient to the first wavelength is higher than 5×10/m. A ratio of the second extinction coefficient to the second wavelength is lower than 5×10/m. Consequently, damage to the surface of the silicon carbide substrate during laser annealing can be reduced.