Determination of facet orientations on alkaline etched multicrystalline wafers

Abstract

In this paper, a method is presented by which the orientations of exposed etch facets, resulting from alkaline saw damage and texture etching, can be determined. The method employs Laue photography, whereby reflected X-ray spots correspond with defined crystallographic planes, and localised light reflection or scatter recordings of He-Ne light reflected preferentially from the faceted etch surface. It is shown that the combination of these two techniques can give the Miller indices corresponding to the surface normals to the etch facets. Angular information is hereby obtained such that the surface geometries of multicrystalline silicon wafers are determined for the two etch types for crystals of different orientation.