Thermal and chemical passivation of gallium-arsenide films deposited from ablation plasma

The electric and photoelectric properties of gallium-arsenide films deposited on a polycrystalline corundum substrate from the ablation plasma formed by a high-power ion beam are investigated. It is ascertained that vacuum and air annealing (in the former case, P = 10^?2 Pa and T = 300–1200 K) and sulfide chemical passivation in an alcoholic solution affect the characteristics of the dark conductivity and photo-conductivity of the film surfaces. The optimal conditions for thermal and chemical treatment, at which the most stable changes in film the properties are attained, are determined. Enhancement in the stability of the electrical and photoelectric characteristics of films, which is achieved after thermal treatment, arises from the annealing of defects and their clusterization. Sulfide passivation leads to changes in the characteristics and increases the stability of properties under air oxidation.