Method for producing semiconductor devices with high reverse blocking capability

US4135291A · kind A · utility

Assignee

• Semikron Gesellschaft fur Gleichrichterbau und Elektronik m.b.H.

Inventors

• Werner Tursky · Schwabach, DE
• Madan M. Chadda · Wendelstein, DE
• Horst Schafer · Aschaffenburg, DE

Key dates

• Filing date: Jul 25, 1977
• Grant date: Jan 23, 1979
• Expiry date: Jul 25, 1997

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/115
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of producing semiconductor devices having high reverse blocking ability comprising initially forming grooves in at least one major surface of a semiconductor disc of a first conductivity type according to a pattern which subdivides the disc into areal sections capable of being separated into individual device-containing semiconductor wafers and then subjecting the disc to a diffusion process to provide in each section a sequence of layer type zones of different conductivities which form at least one pn-junction and with one of the layer zones being a highly resistive zone, and to provide a zone of single conductivity type passing through the entire disc in the profile region of each of the grooves. A recess is then formed in each section of the major surface which is adjacent the pn-junction which is to be stressed in the reverse direction during use of the intended device and adjacent to each of the grooves. The recess extends from the major surface through the surface zone forming a pn-junction with the highly resistive zone into the highly resistive zone. Thereafter at least the surface of the disc containing the recesses is subjected to passivation by covering same wit…