Effect of annealing temperature on the physical properties of NiO thin films and ITO/NiO/Al Schottky diodes

Abstract

Herein, fabrication and characterisation of p-NiO/Al Schottky barrier diodes have been realised by dc reactive magnetron sputtering. In addition, effect of post-annealing temperature was studied. A detailed investigation on the physical properties of the NiO thin films was carried out using structural, morphological, optical, and spectroscopic characterisation tools. The metal–semiconductor interface behaviour has been analysed by current–voltage characterisation by implementing the Thermionic emission and Chueng model. The fabricated diode rectification ratio of 103 has been recorded at ± 3 V, and barrier height varied from 0.53 to 1.10 eV as a function of annealed treatment. A space charge-limited conduction mechanism and tunnelling through the interface trap density of p-NiO/Al Schottky diodes were explained by power law characteristics. Furthermore, we have evaluated the Schottky device's electrical characteristics through the ac measurements which include capacitance densities, dielectric constants, tangent loss, AC conductivity, and Nyquist plots. The present work could provide a better understanding and insight into the p-NiO/Al Schottky junction.