The structure and growth of PbTe films on mica substrates

Abstract

Epitaxial films of PbTe were produced by vacuum evaporation onto air-cleaved mica. Electron and x-ray diffraction shows that the films are well oriented with {111} planes parallel to the substrate, although transmission electron micrographs indicate the presence of double-positioning boundaries. Shadowed carbon replicas were used to examine the mechanism of film growth. Both film structure and electrical mobility were studied as a function of substrate temperature during deposition. At growth temperatures above 400°c, the mobility of molecules on the surface of PbTe films becomes very high, and the surface breaks up into a system of {100} facets. The deposition temperature giving the highest Hall mobility is about 250°c.