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:
Feb. 19, 1991
Filed:
Sep. 25, 1989
Naohito Kato, Chiryu, JP;
Yoshiyuki Miyase, Okazaki, JP;
Tomoatsu Makino, Okazaki, JP;
Kasuhiro Yamada, Oobu, JP;
Masami Yamaoka, Anjo, JP;
Takeshi Matsui, Toyohashi, JP;
Masahiro Yamamoto, Gamagori, JP;
Yoshiki Ishida, Kariya, JP;
Tohru Nomura, Oobu, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
Base regions of first and second stage transistors are formed in a semiconductor substrate consisting of low and high resistivity collector layers, and emitter regions are formed in the respective base regions. The emitter region of the second stage transistor has an interdigital structure with a plurality of finger portions, and an emitter surface electrode is formed on the emitter region of the second stage transistor. The second stage transistor emitter surface electrode has an extending portion at a position spaced apart from a transistor operation region where the finger portions are formed. An emitter connection electrode is formed on the extending portion, and a lead is connected by soldering or the like to the emitter connection electrode. In a portion of the emitter surface electrode extending from the emitter connection electrode to the transistor operation region, slits are formed such that they are bypassed by emitter current so that the lead resistance from each finger portion to the emitter connection electrode is substantially uniform.