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:
Aug. 31, 1993
Filed:
Oct. 15, 1991
Chao Huang, Agoura Hills, CA (US);
Kenneth Kosai, Goleta, CA (US);
Joan K Chia, Santa Barbara, CA (US);
Santa Barbara Research Center, Goleta, CA (US);
Abstract
A mercury-cadmium-telluride (HgCdTe) photoresponsive layer (14) having the composition Hg.sub.1-x Cd.sub.x Te is formed on a substrate (12) such that x increases from the surface (14a) of the photoresponsive layer (14) toward the substrate (12). This causes the bandgap in the photoresponsive layer (14) to increase from the surface (14a) toward the substrate (12), thereby urging minority carriers which are photogenerated in the photoresponsive layer (14) to move toward and be trapped at the surface (14a). Laterally spaced first and second ohmic contacts (16,18) are electrically connected to the photoresponsive layer (14) at a predetermined distance (z.sub.c) below the surface (14a) such that the photogenerated minority carriers trapped at the surface (14a) are urged away from the contacts (16,18) by the increasing bandgap. An electrically floating photoresponsive layer (24) of opposite conductivity type may be formed between the substrate (12) and the photoresponsive layer (14) to form a Heterojunction Interface Trap.