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:
Mar. 30, 1993
Filed:
Mar. 19, 1991
Toshio Ohshima, Atsugi, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
A heterojunction semiconductor device utilizing a quantum-mechanical effect comprises a first compound semiconductor (e.g., AlGaAs) layer and a second compound semiconductor (e.g., GaAs) layer having an electron affinity different from that of the first semiconductor layer, and the first and second compound semiconductor layers forming a heterojunction interface therebetween, the first layer having an energy at the conduction band bottom thereof higher than that of the second layer and doped with donor impurities, wherein at least one concave or convex portion of the first semiconductor layer is formed at the heterojunction interface and both sides of the concave or convex portion serve as a potential well or potential barriers against electrons accumulated in the second semiconductor layer close to the vicinity of the heterojunction interface.