Patent ID: 7579261

Claim:
A method for producing epitaxially coated silicon wafers, comprising: providing a multiplicity of silicon wafers polished on at least their front sides, and successively and individually coating each wafer in an epitaxy reactor by a procedure comprising placing a silicon wafer on a susceptor in an epitaxy reactor, pretreating the wafer under a hydrogen atmosphere at a first hydrogen flow rate in a first step, and pretreating with addition of an etching medium to the hydrogen atmosphere at a reduced hydrogen flow rate in a second step, subsequently epitaxially coating the wafer on at least its polished front side, and removing the wafer from the epitaxy reactor, wherein an etching treatment of the susceptor with an etching medium is effected after epitaxial coating of one or more wafers, and wherein the epitaxially coated silicon wafers have a global flatness value GBIR of 0.07-0.3 μm relative to an edge exclusion of 2 mm, wherein the first hydrogen flow rate is from about 20-100 slm, and the second hydrogen flow rate is about 0.5 to 10 slm.