Interdiffusion in amorphous Si/Ge multilayers by Auger depth profiling technique

It has been shown by the Auger depth profiling technique that the concentration profile at the initially sharp Si/Ge interface in amorphous Si/Ge multilayers shifted but remained still sharp after a heat treatment at 680 K for 100 h. At the same time the fast diffusion of Si resulted in the formation of an almost homogeneous Ge(Si) amorphous solid solution, while there was practically no diffusion of Ge into the Si layer. This is direct evidence on the strong concentration dependence of the interdiffusion coefficient in amorphous Si/Ge system, and it is in accordance with the previous indirect result obtained from the measurements of the decay of the small angle Bragg peaks, as well as with finite difference simulations. (C) 2001 American Institute of Physics.