EFFECT OF COMPOSITION FLUCTUATIONS IN Ge-Si SOLID SOLUTIONS.

A theoretical study is made of the effect of fluctuations of the composition of Ge//1// minus //xSi//x solid solutions on the hole mobility. The measurements of the temperature dependence of the mobility are quoted for a series of p-type Ge//1// minus //xSi//x samples (0. 004 less than equivalent to x less than equivalent to 0. 08) with identical impurity compositions. A comparison of the experimental and calculated results indicates that Si is contained in Ge in the form of clusters of K atoms rather than single atoms, where K equals 30-150. This conclusion is consistent with the data on the hopping conductivity of such samples.