Fabrication of ON/OFF switching response based on n-Ni-doped MoO3/p-Si junction diodes using Ni-MoO3 thin films as n-type layer prepared by JNS pyrolysis technique

Abstract

The influence of nickel (Ni) doping concentrations on structural, optical, electrical and diode properties of molybdenum trioxide (MoO3) thin films has been studied systematically. Ni-doped MoO3 films and diodes were prepared for various doping concentrations of Ni such as 0, 3, 6 and 9 wt.% by jet nebulizer spray (JNS) pyrolysis technique. The structural properties of Ni-doped MoO3 films were analyzed by X-ray diffraction (XRD) pattern and scanning electron microscopy (SEM). The prepared films were exhibited in the orthorhombic crystal structure and sub-microsized plate-like surface morphology. The energy-dispersive X-ray spectroscopy (EDX) analysis confirmed the presence of Ni, Mo and O elements in the prepared films. Ultraviolet–visible (UV–vis) analysis results showed that the absorbance decreases with the increasing of Ni doping concentration and the minimum band gap energy (Eg = 2.25) was obtained for 9 wt.% Ni-doped MoO3 film. From current–voltage (I–V) characterization, the conductivity is increased by increasing the Ni doping concentration in MoO3 thin films. The diode measurements were performed in darkness and under light illumination of a halogen lamp. The methods of I–V, Cheung’s and Norde were used to calculate the diode parameters of ideality factor (n), barrier height (Φb) and sheet resistance (Rs). Also, the light ON/OFF switching response of the fabricated n-NiMoO3/p-Si diodes was analyzed.