Crystal orientation detection for single-crystal surface

摘要

The method involves measuring light that has been emitted by a light source (4) and reflected by the surface (2). The light is measured as a function of an azimuth angle. The light reflected by microscopically small cracks of the surface, which are formed in the production process, is measured under rotation of the crystal (1), in response to an angular position. Angular differences of respectively adjacent intensity maxima are determined from intensity measurements of the reflected light, and are compared with reference values of a simulation model, which describes the ideal position of the crack levels. The difference from the angular position of each simulated and determined intensity maximum is calculated, and an average is calculated from all the differences. An empirical correction value is added to the average, to eliminate a process-dependent distortion of the crystalline structure produced during the manufacture of the crystal.