Nonlinear-optical diagnostics of semiconductor film crystal structures

Abstract Second harmonic (SH) generation in transparent semiconductor films is discussed. It is shown that reflected radiation from the back film side gives an essential input in the reflected SH. Such registration scheme is more sensitive, and the effects of film thickness variation can be eliminated. An efficient method for film crystal quality control can be developed on the basis of this scheme. The method can indicate the regions with different qualities and define their localization. The SH interference dependence versus the film thickness dependence can be used for “in situ” film monitoring in a high-vacuum device.