Electrical properties of Bi<inf>80</inf>Sb<inf>20</inf> alloy thin films, vacuum-deposited at different substrate temperatures

Bismuth antimonide (composition 80:20) alloy thin films have been prepared by vacuum deposition at different substrate temperatures and, after annealing, their resistances have been recorded as a function of temperature, between 77 K and 500 K. The observed resistance against temperature behaviour of the films, and the effect of thickness and substrate temperature during deposition of the films, has been explained by considering that these films behave as semiconductors; the overlap between valence and conduction bands being removed due to the presence of antimony, the influence of a quantum size effect and the fact that the grain size of the films formed is a function of thickness and substrate temperature. © 1981 Chapman and Hall Ltd.