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:
Jul. 27, 1982
Filed:
Apr. 18, 1980
Rudolf P Tijburg, Eindhoven, NL;
Teunis van Dongen, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An electroluminescent semiconductor device such as a semiconductor laser has epitaxial monocrystalline layers (3 to 6), including an active layer (4), grown on a substrate (2). The epitaxial layers are etched in the presence of an etching mask (8) to form nonplanar mirror surfaces (9) which in the longitudinal direction bound active regions (10). To form flat and parallel mirrors (12) an epitaxial monocrystalline protective layer (11) is grown from the gaseous phase on the mirror surfaces after etching. The etching can be carried out in two stages using different etchants. With the first etchant the etched layers taken on a swallow-tail profile and then with the second etchant they take on a concave profile.