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. 11, 2023
Filed:
Nov. 30, 2018
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Isao Obu, Nagaokakyo, JP;
Yasunari Umemoto, Nagaokakyo, JP;
Masahiro Shibata, Nagaokakyo, JP;
Shigeki Koya, Nagaokakyo, JP;
Masao Kondo, Nagaokakyo, JP;
Takayuki Tsutsui, Nagaokakyo, JP;
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Abstract
A bipolar transistor including a first collector layer, a second collector layer, a base layer, and an emitter layer is disposed on a substrate. Etching characteristics of the second collector layer are different from etching characteristics of the first collector layer and the base layer. In plan view, an edge of an interface between the first collector layer and the second collector layer is disposed inside an edge of a lower surface of the base layer, and an edge of an upper surface of the second collector layer coincides with the edge of the lower surface of the base layer or is disposed inside the edge of the lower surface of the base layer.