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. 29, 1997
Filed:
May. 26, 1995
Klas Lilja, Fislisbach, CH;
Asea Brown Boveri Ltd., Baden, CH;
Abstract
A controlled turn-off power semiconductor device is proposed which is subdivided into unit cells and which comprises five layers in a p-n-p-n-p sequence, namely a p-type emitter layer (9), an n-type base layer (8), a p-type base layer (7), an n-type emitter layer (6) and a p-doped contact region (5) between an anode (a) and a cathode (K). In every unit cell a first MOSFET (M1) which can be driven via a first insulated gate (G1) is provided on the cathode side for switching between the five-layer structure and a conventional thyristor four-layer structure. Further, a breakdown between the contact region (5) and the n-type emitter layer (6) is prevented during turning-off. As a result of the switchable five-layer structure, a current filamentation is effectively avoided during turning-off.