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:
May. 29, 1990
Filed:
Dec. 22, 1987
Kazuhiko Honjo, Tokyo, JP;
Shin-Ichi Tanaka, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
For improvement in operation speed, there is provided a heterojunction bipolar transistor comprising, (a) an emitter region formed of a first semiconductor material of a first conductivity type, (b) a base region formed of a second semiconductor material of a second conductivity type opposite to the first conductivity type and forming a first junction together with the emitter region, and (c) a collector region formed of a third semiconductor material of the first conductivity type and forming a second junction together with the base region, the heterojunction bipolar transistor has a plurality of abrupt potential discontinuities including first and second abrupt potential discontinuities produced in succession to provide kinetic energies to a carrier injected from the emitter region, respectively, and the first abrupt potential discontinuity is produced at one of the first and second junctions, thereby allowing the carrier to move over a distance longer than a mean free path of the carrier in the ballistic manner.