EPITAXIALLY COATED SILICON WAFER AND METHOD FOR PRODUCING EPITAXIALLY COATED SILICON WAFER

• Main Authors: LAUBE FRANK, FRIEDRICH PASSEK, SCHAUER REINHARD, PICKEL MARTIN
• Format: Patent
• Language: English
• Published: 08.08.2013
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; BASIC ELECTRIC ELEMENTS; CHEMISTRY; CRYSTAL GROWTH; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; SEMICONDUCTOR DEVICES; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

PROBLEM TO BE SOLVED: To provide an epitaxially coated silicon wafer having an improved image quality and a suitable method for producing an epitaxially coated silicon wafer.SOLUTION: A method for producing an epitaxially coated silicon wafer includes steps of: providing a group of silicon wafers having rounded edges; polishing the edges of the silicon wafers; cleaning the silicon wafers; examining the edge regions of the group of silicon wafers with regard to defects and edge roughness and selecting silicon wafers from the group of silicon wafers which have a surface roughness of less than 1 nm RMS relative to a spatial wavelength range of 10-80 μm; pretreating the selected silicon wafers in a single wafer epitaxy reactor, and in a first step, a treatment in a hydrogen atmosphere at a flow rate of 1-100 slm is effected and, in addition, in a second step, an etching medium with a flow rate of 0.5-5 slm is added to the hydrogen atmosphere and is distributed in the reactor chamber by means of a gas distribution device; and epitaxially coating the silicon wafer.