The effect of substrate temperature on the preparation of molybdenum oxide thin films by spray pyrolysis method used in diode

In this research, the diodes were made using a thin films of molybdenum oxide on the doped P-type silicon substrate with the aim of studying the effect of the substrate temperature on the characteristics of the diode. For this purpose, thin films of molybdenum oxide were deposited on the substrate at substrate temperatures of 350, 400, 450 and 500 ˚C by spray pyrolysis. The structural and optical properties of the thin films were characterized. They show a fairly crystalline nature with a straight structure and peaks corresponding to (020), (040) and (060) planes, with the preferred peak being (040) in all samples. The shape of the surface of the samples is without cracks and has a rectangular granulation with the size of the grains in the range of 110 to 210 nm. Also, their average surface roughness was measured in the range of 157 to 167 nm. The optical gap of the samples was estimated in the range of 2.84 to 2.95 eV. The voltage-current diagram of the samples showed their diode behavior. The diode made at 400 ˚C substrate temperature has the lowest threshold voltage.