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. 21, 1976
Filed:
Sep. 19, 1975
Wilbur Dexter Johnston, Jr, Holmdel, NJ (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
A high efficiency solar cell having n-type aluminum arsenide grown on a p-type gallium arsenide substrate and protected by a layer of anodic oxide. The aluminum arsenide is deposited by vapor phase epitaxy by reacting high purity arsine, hydrogen chloride and aluminum at approximately 1000.degree.C in an all-alumina reactor tube system. The aluminum arsenide layer is protected from deterioration by first anodizing it in pure water and phosphoric acid at pH 2.0 with a current density of 2-8 milliamperes per square centimeter at room temperature. Second, the anodic oxide so formed is annealed at about 450.degree.C for at least twenty minutes in dry nitrogen. The oxide layer also acts as an antireflective coating. A portion of the oxide layer is etched away to expose a region of the aluminum arsenide to which an electrical contact is applied. The other contact is made to the substrate.