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:
Jul. 18, 2023
Filed:
Aug. 12, 2020
Applicant:
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Inventors:
Assignee:
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 29/737 (2006.01); H01L 29/205 (2006.01); H01L 29/10 (2006.01); H01L 29/66 (2006.01); H01L 29/08 (2006.01); H01L 21/285 (2006.01); H01L 21/308 (2006.01); H01L 21/306 (2006.01); H03F 3/21 (2006.01);
U.S. Cl.
CPC ...
H01L 29/7371 (2013.01); H01L 21/28575 (2013.01); H01L 21/308 (2013.01); H01L 21/30612 (2013.01); H01L 29/0821 (2013.01); H01L 29/1004 (2013.01); H01L 29/205 (2013.01); H01L 29/66318 (2013.01); H01L 29/0817 (2013.01); H01L 29/0826 (2013.01); H03F 3/21 (2013.01);
Abstract
A heterojunction bipolar transistor includes a collector layer, a base layer, and an emitter layer that are stacked on a substrate. The collector layer includes a graded semiconductor layer in which an electron affinity increases from a side closer to the base layer toward a side farther from the base layer. An electron affinity of the base layer at an interface closer to the collector layer is equal to an electron affinity of the graded semiconductor layer at an interface closer to the base layer.