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:
Apr. 16, 1996
Filed:
Apr. 07, 1994
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
The present invention provides a heterojunction bipolar transister includes: a collector layer, a base layer, an emitter layer, a transition layer formed between the base layer and the emitter layer, a collector electrode connected to the collector layer, a base electrode connected to the base layer, and an emitter electrode connected to the emitter layer, wherein the emitter layer and the transition layer are formed of a composition including elements forming the base layer and at least one element different from the elements forming the base layer, a composition of the different element in the transition layer at the emitter side is substantially equal to that of the emitter layer, a composition of the different element in the transition layer at the base side is smaller than that of the emitter side and varies abruptly towards the base layer, and the composition of the transition layer gradingly varies from the base side to the emitter side.