Effect of a semiconductor coating on electron transport in amorphous and crystalline metal films

The effect of an amorphous Sb coating on the resistivity ρ of amorphous and crystalline V, Yb, and Bi films is investigated. The values of ρ decrease for both phase states of V and Bi and increase for Yb. The effect of a coating on ρ is limited by the thickness of the coating dcov0=10–16nm, depending on the type and phase state of the base metal. Increasing the coating thickness to dcov>dcov0 does not change ρ further. The observed changes in ρ are attributed to electron flow from amorphous antimony into Bi and V and from amorphous and crystalline Yb films into amorphous antimony with a contact potential difference forming between the metal and semiconductor layers. In the process the density of states of the conduction electrons in the metal changes, and this is responsible for the change in ρ.