Tin Selenide Thin Films Deposited by Ultrasonic Spray Pyrolysis for Photovoltaic Applications

Abstract

Tin Selenide films were deposited by ultrasonic spray pyrolysis (USP) technique onto glass substrates. 1, 1-dimethyl-2- Selenourea and SnCl2 were used as precursors of Se and Sn respectively. The X-ray technique shows that the deposited film is of a crystalline nature, identifying the SnSe compound, SnSe2 and SnO2 crystals. The obtained thin films were annealed at 300°C in an H2 atmosphere for 30 minutes to improve the purity of SnSe material. The XRD of the annealed films shows almost no signs of SnSe2 crystals. The measured value of the energy band gap (Eg) of the deposited SnSe films decreases after annealing treatment, from 1.23 eV to 1.09 eV. Seebeck effect showed p-type electrical conductivity in both films and Hall effect show almost no changes in the density of carrier charges and conductivity after annealing the samples. The fabricated devices show the photovoltaic effect with different values depending on the materials used.