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:
Oct. 27, 2020
Filed:
Feb. 20, 2020
Visual Photonics Epitaxy Co., Ltd., Taoyuan, TW;
Chao-Hsing Huang, Taoyuan, TW;
Yu-Chung Chin, Taoyuan, TW;
Min-Nan Tseng, New Taipei, TW;
Kai-Yu Chen, Taoyuan, TW;
VISUAL PHOTONICS EPITAXY CO., LTD., Taoyuan, TW;
Abstract
Provided is a heterojunction bipolar transistor (HBT) structure with a bandgap graded hole barrier layer, including: a sub-collector layer including an N-type group III-V semiconductor on a substrate, a collector layer on the sub-collector layer and including a group III-V semiconductor, a hole barrier layer on the collector layer, a base layer on the hole barrier layer and including a P-type group III-V semiconductor, an emitter layer on the base layer and including an N-type group III-V semiconductor, an emitter cap layer on the emitter layer and including an N-type group III-V semiconductor, and an ohmic contact layer on the emitter cap layer and including an N-type group III-V semiconductor. Bandgaps of the hole barrier layer at least include a gradually increasing bandgap from the base layer towards the collector layer and a largest bandgap of the hole barrier layer is greater than bandgap of the base layer.