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:
Jan. 03, 1989
Filed:
Nov. 25, 1987
Keiro Komatsu, Tokyo, JP;
Masahiko Fujiwara, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a semiconductor layer which has in a semiconductor bistable etalon a refractive index variable, as a result of absorption by excitons, with the intensity of an optical beam incident thereon, an optical guide for the optical beam is surrounded by a cladding portion including atoms which reduce the refractive index in the cladding portion relative to the optical guide and serve as recombination centers for free carries produced by decomposition of the excitons. The semiconductor layer may be either a superlattice layer, such as a GaAs-GaAlAs layer, or a bulk semiconductor layer, such as a GaAs layer. After forming the semiconductor layer on an etch-stop layer which is formed on a semiconductor substrate for chemical etch of the substrate for a window, the atoms are injected into the surrounding portion as by bombarding an exposed surface of the semiconductor layer by hydrogen ions with a mask selectively formed on the exposed area to cover an area contiguous on the exposed surface to a columnar portion which becomes the optical guide. The hydrogen ions automatically become the atoms of the above-described type in the surrounding portion.