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:
Jun. 15, 1999
Filed:
Dec. 20, 1996
Masataka Watanabe, Gunma-ken, JP;
Tsuneyuki Kaise, Gunma-ken, JP;
Masayuki Shinohara, Gunma-ken, JP;
Masahisa Endou, Gunma-ken, JP;
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Abstract
A compound semiconductor epitaxial wafer added with nitrogen to provide a high luminous efficiency. Epitaxial layers are grown on a single crystalline substrate 4 made of gallium phosphide or gallium arsenide to form a compound semiconductor epitaxial wafer EW. The epitaxial layers include at least an nitrogen-added gallium phosphide arsenide mixed crystalline epitaxial layer having an n-type carrier concentration descending gradually toward the uppermost surface of the grown layer in a continuous or stepwise manner before p-type impurity is diffused, and contain an intermediate layer 83 with an n-type carrier concentration of 4.times.10.sup.14 /cm.sup.3 or more and less than 3.5.times.10.sup.15 /cm.sup.3, and a surface layer 84 having an n-type carrier concentration equals to or lower than that for the intermediate layer 83.