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:
Nov. 12, 2019
Filed:
Dec. 07, 2015
Sumitomo Electric Industries, Ltd., Osaka-shi, Osaka, JP;
Shinya Fujiwara, Itami, JP;
Yasuaki Higuchi, Itami, JP;
Sumitomo Electric Industries, Ltd., Osaka-shi, Osaka, JP;
Abstract
An indium phosphide substrate, a method of inspecting thereof and a method of producing thereof are provided, by which an epitaxial film grown on the substrate is rendered excellently uniform, thereby allowing improvement in PL characteristics and electrical characteristics of an epitaxial wafer formed using this epitaxial film. The indium phosphide substrate has a first main surface and a second main surface, a surface roughness Raat a center position on the first main surface, and surface roughnesses Ra, Ra, Ra, and Raat four positions arranged equidistantly along an outer edge of the first main surface and located at a distance of 5 mm inwardly from the outer edge. An average value mof the surface roughnesses Ra, Ra, Ra, Ra, and Rais 0.5 nm or less, and a standard deviation σof the surface roughnesses Ra, Ra, Ra, Ra, and Rais 0.2 nm or less.