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:
May. 31, 1977
Filed:
Jan. 21, 1976
Hajime Yagi, Tokyo, JA;
Tadaharu Tsuyuki, Isehara, JA;
Sony Corporation, Tokyo, JA;
Abstract
This invention relates to a bidirectional transistor, and particularly to a transistor having two low impurity concentration regions on either side of a base region which act as the emitter or collector regions with a minority carrier diffusion length L substantially greater than the width of such emitter and collector regions when operating in either direction. High impurity concentration regions interface with the low impurity concentration regions to provide a built-in-field which is larger than kT/(qL) and which make the drift current produced by the built-in-field substantially balance the minority carrier diffusion current injected from the base region. The built-in-field is preferably larger than 10.sup.3 V/cm, and the potential barrier across is preferably larger than 0.1 eV. Two of the high impurity concentration regions provide first and second L-H junctions. A third L-H junction surrounds one of the low impurity concentration regions. This third L-H junction greatly improves the bidirectional characteristics of the device.