The resistance to flow of electrons in these amorphous semiconductors which have very high density of localized states may be controlled by hopping processes according to Lazarus. However, no theoretical calculations for the electrical resistance of these amorphous semiconductors have been carried out to the best of our knowledge. In the present work, we have tested an alternative approach which is based on the fundamental assumptions of Drickamer. It has been stated by Drickamer that the basic effects of pressure on a material are; (1) to decrease interatomic distance and (2) to increase overlap between adjacent electronic orbitals. Apart from these assumptions, Drickamer, however, has not put forward any formulation for the explanation of his measurements. A simple phenomenological formulation based on these fundamental assumptions has been tested successfully in case of some semiconductors as hydrogenated and non-hydrogenated amorphous silicon (a-Si: H and a-Si), germanium and selenium.
