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:
Nov. 30, 1993
Filed:
Aug. 02, 1991
Hiroya Sato, Tenri, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
According to the present invention, the hetero junction bipolar transistor (HBT) is provided which includes an emitter layer consisting of a first semiconductor of a first conductive type and being in mesa form; a base layer being in contact with the emitter layer and consisting of a second semiconductor of a second conductive type having a narrower band gap than the first semiconductor; and a collector layer being in contact with the base layer and consisting of a third semiconductor of a first conductive type having a broader band gap than the second semiconductor. In this HBT, a monolayer sulfur film is formed so as to cover the exposed periphery of the heterointerface between the emitter layer and the base layer.