Electrical response and microstructure development in zinc oxide films sprayed from ethanolic solutions of different salts

Abstract

Zinc oxide thin films were grown by spray-pyrolysis on glass substrates from ethanolic solutions of zinc nitrate, zinc chloride and zinc acetate. Different microstructures were observed in the films prepared with the three salts used, which showed significant differences with respect to films prepared from aqueous solutions of the same salts. Polyethyleneglycol was also used as a pore-generating agent in order to modify the microstructure of denser films increasing the degree of porosity. The electrical response of the films at room temperature was evaluated under 365 nm ultraviolet light, and in the presence of hydrogen, separately. The microstructures developed in ZnO films by using different zinc salts is correlated with the measured electrical properties.