Based on structural investigations by electron microscopy and small‐angle diffraction technique an inhomogeneous model is developed for the electronic structure of amorphous Ge and Si films. The density‐of‐states function in the pseudo‐gap and the position of the Fermi level are studied as a function of contamination and annealing, supposing that oxygen contamination of internal surfaces is the most important process. The annealing behaviour of dc conductivity and thermopower is then discussed for both the hopping and activation regime. The model is shown to be consistent with a large number of transport data of these films.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics