Interaction between post wire saw cleaning and the subsequent cell fabrication saw damage etch and texturing process

Abstract

Post wire saw wafers presented for cleaning are heavily contaminated with cutting fluid slurry, silicon kerf, trace metallic species and oxides. There is no industry standard process or equipment set for this operation with various options utilised by the wafer manufacturer. However a common theme is the use of chemical cleaners to facilitate removal of the debris and contaminants. This paper describes studies conducted to determine potential effects of differing cleaner chemistry types on subsequent cell fabrication. By characterisation of contact angle, topography, etch depth and reflectance it is shown that certain cleaner types can have a profound and potentially adverse effect on the texture process and pyramid generation. Potential mechanisms are discussed and additional studies demonstrating that such adverse effects can be rectified are described.