Effect of Process Variables on Deposited Cupric Oxide Thin Film by Sol-Gel Spin Coating Technique

Abstract

Cupric oxide were prepared by sol-gel technique and deposited onto glass substrates as thin films using spin coating method. The aim of this research was to study the effects of different spin coating speeds and solution concentrations of cupric oxide thin films on the structural, optical, electrical and physical properties of thin films. Thin films were deposited with concentration variation of the solution ranging from 0.5 M-1 M and speed variation from 1200 rpm-2400 rpm. X-ray diffraction (XRD) and UV-Vis spectrophotometer were used to characterize the structural and optical properties of the deposited films, respectively. The as-synthesized CuO thin films were also characterized using SEM. The dc electrical properties were characterized using nano-electrometer. Based on the results obtained, it was found that the electrical resistivity of the cupric oxide thin films increases as spin coating speeds increase. The optical band gap values of CuO thin films for concentration variation were found 1.47-1.27 eV and for speed variations, it was observed 1.45-1.95 eV. Decreased values of the optical energy gap were observed with increasing concentration while reverse effect was found with increasing speed of spin coating.