Role of substrate temperature on MoO3 thin films by the JNS pyrolysis technique for P–N junction diode application

Abstract

Molybdenum trioxide (MoO3) thin films were prepared at different substrate temperatures from 350 to 500°C by the jet nebulizer spray (JNS) pyrolysis technique. The effect of the substrate temperature on the structural, optical and electrical properties of MoO3 films was characterized. The XRD pattern exposed that the crystallite size of the films increases with the increase in the substrate temperature. The SEM images showed the conversion of nanorods to sub-microsized plate-like structures by increasing the substrate temperature. The EDX analysis confirmed the presence of Mo and O elements. The UV–vis results revealed that the band gap obtained shows a decreasing trend on increasing the substrate temperature. The FTIR spectra confirmed the formation of MoO3. The dc electrical studies portrayed the minimum activation energy of 0.064eV obtained for higher substrate temperature. The P–N diode of p-Si/n-MoO3 was fabricated at the substrate temperature of 500°C. The diode parameters such as ideality factor (n), barrier height (Φb) and reverse saturation current (I0) values were calculated in darkness and under different light sources (Halogen and Metal halide lamps).