摘要 |
A silicon wafer is provided having a polished front surface with an epitaxial coating and a polished back surface, which is distinguished by a SFQRmax value of less than or equal to 0.10 mum (26 mmx8 mm; 99%). There is also a process for producing silicon wafers of this type by sawing up a single crystal, carrying out an abrasive step, simultaneously polishing a front surface and a back surface of at least three silicon wafers, and applying an epitaxial coating. This process includes the following conditions being satisfied simultaneously: (a) before the simultaneous polishing, the silicon wafers have a concave thickness distribution, the center thickness being 1 mum to 10 mum lower than the edge thickness, and this thickness difference differing by less than or equal to 3 mum within one polishing run; (b) the mean thickness of the silicon wafers prior to the simultaneous polishing differs by less than or equal to 3 mum within one polishing run; and (c) the thickness of the carriers used during the simultaneous polishing is 1 mum to 5 mum lower than the thickness of the finished polished silicon wafers.
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