Ellipsometry for rapid characterization of Si1−xGex layers

Abstract
We report on the ability of ellipsometry to rapidly determine the germanium content and the film thickness of Si1−xGex layers deposited on silicon substrates. The technique is used to evaluate thickness on single‐ and for the first time, double‐layer Si/SixGe1−x films. We estimate the refractive index of Si1−xGex from ellipsometry measurements and find that only the real part differs significantly from that of silicon for 0<xx∼0.10.