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. 15, 1994
Filed:
Jun. 26, 1992
ASEA Brown Boveri Ltd., Baden, CH;
Abstract
A turn-off power semiconductor component subdivided into unit cells (EZ), including between an anode (A) and a cathode (K) in a semiconductor substrate (1) five layers in p-n-p-n-p sequence, namely an anode layer (10) an n-type base layer (9), a p-type base layer (8), a turn-off region (6), a cathode region (7) adjoining the turn-off region, and a p-doped short-circuit region (5). On the cathode side in every unit cell (EZ), a first MOSFET (M1) which can be driven via a first insulated gate electrode (G1) is provided for the purpose of switching between the five-layer structure and a conventional thyristor four-layer structure. A second MOSFET (M2) having a second gate electrode (G2) prevents a breakdown between the p-type short-circuit region (5) and the turn-off region (6) during turn-off. p-Type short-circuit region (5), turn-off region (6) and cathode region (7) are introduced in a self-aligning manner into the semiconductor substrate (1) through the windows (F1, F2) between the gate electrodes (G 1 and G2, respectively). Current filamentation during turn-off is effectively avoided by the switchable five-layer structure. The self-aligning production makes possible a component having precise patterning.