Textural development of SiC and diamond wire sawed sc-silicon wafer

The present work compares the time-dependent evolution of the surface morphology during the horizontal acidic etching of diamond wire (DW) and SiC slurry (SP) sawn single-crystalline wafer by means of scanning electron microscopy (SEM), confocal microscopy, reflectivity measurements, and the measurement of the etch rates. Both sawing processes lead to different as cut structures which have a significant impact on the evolution of the wafer surface morphology during the acidic etching. This initial structure controls the sites where the chemical attack preferentially occurs and affects therefore to a considerable extent the morphology of the etched surface as well as the rate of which this morphology is formed. Based on the experimental results is discussed why the texturization of DW sawn wafers remains incomplete if acidic etch mixtures and etch parameters are used that were optimized for the etching of SP wafers. To create homogeneously texturized DW sawn wafers of low reflectivity the development of new etchants and new etch conditions for is necessary.