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:
Sep. 02, 1980
Filed:
Oct. 25, 1978
Yet-Zen Liu, Roanoke, VA (US);
Shang-Yi Chiang, Richardson, TX (US);
International Telephone and Telegraph Corporation, New York, NY (US);
Abstract
A small-area light-emitting diode of the surface-emitting type has a double heterojunction semiconductor structure grown on a substrate. A semiconductor blocking layer having a hole formed therein is disposed between the substrate and the layers of the double heterojunction semiconductor structure to confine the transverse current flow for greater efficiency. A metallic contact layer is formed on the surface of the double heterojunction semiconductor structure on the side opposite the substrate and has a registering hole formed therein having a size approximately equal to the size of the hole formed in the semiconductor blocking layer and disposed in registration therewith along an axis perpendicular to the layers. The cap layer of the double heterojunction semiconductor structure may include a hole etched therethrough and in registration with the previously mentioned holes for better light emission. In a further embodiment, the light-emitting layer is restricted in surface area to a region aligned with said holes for even greater light efficiency and current confinement.