Coevaporated amorphous Ge1-xMox films (0.07≤x≤0.32) were investigated by means of electron microscopy electron and X-ray diffraction and electrical measurements. Inhomogeneity in the Mo concentration has been found only in the samples of high metal content. Mo causes drastic changes in the ED and XRD patterns of a-Ge. The experimental interference functions for x≤0.22 are well matched by those calculated on the basis of a structural model for a relaxed a-Ge random network in which the Mo atoms fill part of the empty space. In the range 80-470 K both samples with x=0.07 and 0.16 display activation energies ΔE 6 times less than those of a-Ge and close to kBT, which is indicative of hopping on high density localized states. Below 80 K for the samples of high Mo content ΔE becomes very small suggesting the presence of metallic regions, which dominate conduction at low T.
ASJC Scopus subject areas
- Nuclear and High Energy Physics