Light fired thyristor with faulty firing protection

US4122480A · kind A · utility

Assignee

• Licentia Patent-Verwaltungs-GmbH · DE

Inventors

• Dieter Silber · Eschborn, DE
• Karl-Julius Finck · Frankfurt, DE
• Marius Fullmann · Neu-Isenburg, DE
• Wolfgang Winter · Eschborn, DE

Key dates

• Filing date: Nov 3, 1976
• Grant date: Oct 24, 1978
• Expiry date: Nov 3, 1996

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10F30/263

Abstract

A light fired thyristor including a semiconductor body having four zones of alternatingly opposite conductivity types constituting a first or cathode emitter zone, a control base zone adjacent thereto, a main base zone and a second or anode emitter zone with the cathode emitter zone being formed within the control base zone at one major surface of the semiconductor body and being divided into a plurality of separate regions of which one serves as the firing region of the first emitter zone to fire the thyristor in response to impinging radiation energy. The firing region of the first emitter zone is provided in part with a first ohmic contact which is ohmically connected to a further ohmic contact connected to the control base region adjacent the edge of the semiconductor body. The remaining regions of the first emitter zone are provided with a cathode contact which simultaneously contacts the portions of the control base zone between these regions and forms short circuits with the control base zone. Consequently with interfering currents which are approximately uniformly distributed over the thyristor area, an increase in potential is produced in the firing region of the first emi…