Method for producing epitaxially coated silicon wafers

US8372298B2 · kind B2 · utility

Assignee

• Siltronic AG · DE

Inventor

• Joerg Haberecht · Freiberg, DE

Key dates

• Filing date: Feb 2, 2010
• Grant date: Feb 12, 2013
• Expiry date: Aug 31, 2030

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/02661
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Epitaxially coated silicon wafers, are coated individually in an epitaxy reactor by a procedure in which a silicon wafer on a susceptor in the epitaxy reactor, is pretreated in a first step with a hydrogen flow rate of 1-100 slm and in a second step with hydrogen and an etching medium at a hydrogen flow rate of 1-100 slm, and an etching medium flow rate of 0.5-1.5 slm, at an average temperature of 950-1050° C., and is subsequently coated epitaxially, wherein, during the second pretreatment step, the power of heating elements is regulated such that there is a temperature difference of 5-30° C. between a radially symmetrical central region of the silicon wafer and an outer region of the silicon outside the central region.