Process for producing an epitaxial layer with laterally varying doping

US6171935A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Paul Nance · Sunnyvale, US
• Wolfgang Werner · Hersbruck, DE

Key dates

• Filing date: May 24, 1999
• Grant date: Jan 9, 2001
• Expiry date: May 24, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S438/969
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A process for producing an epitaxial layer with laterally varying doping includes the following steps: (a) applying a patterned insulator layer to a semiconductor body; (b) growing a first epitaxial layer on the semiconductor body and the patterned insulator layer so that monocrystalline regions are formed over the semiconductor body and polycrystalline regions are formed over the patterned insulator layer, the angle of inclination (.alpha.) of the interface between the monocrystalline regions and the polycrystalline regions depending on the grain size of the polycrystalline regions; (c) removing the polycrystalline regions and the insulator layer, and (d) growing a second epitaxial layer which, together with the monocrystalline regions of the first epitaxial layer, forms the epitaxial layer.