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:
Mar. 20, 1990
Filed:
Apr. 04, 1988
Peter Roggwiller, Riedt-Neerach, CH;
BBC Brown Boveri AG, Baden, CH;
Abstract
A gate turn-off thyristor (GTO) having a semi-conductor substrate (1) with at least one p-conducting anode layer (4), one n-type base layer (6), one p-type base layer (7) which is in electrical contact with a gate, and one n-conducting cathode layer (8) has a cathode layer (8) with a highly doped zone (10) acting as n.sup.+ emitter and a lightly doped zone (9). The highly doped zone (10) adjoins the surface of the semi-conductor substrate (1) and has a doping density which is at least an order of magnitude higher than that of the p-type base layer (7). The lightly doped zone (9) is situated between a pn junction J.sub.1, produced by the p-type base layer (7) and the cathode layer (8), and the highly doped zone (10) of the cathode layer (8). In a preferred embodiment of the invention, the highly doped zone (10) is so structured that the lightly doped zone (9) extends, in a GTO with mesa structure, from the pn junction J.sub.1 to the surface of the semi-conductor substrate (1) in a central strip (5) of the cathode fingers (2). A method for producing GTO's according to the invention is furthermore specified.