Thickness Effect on the Structure and Electrical Properties of ZnO Thin Films

Abstract

The objective of this research is studing the effectes of the thickness on the structur ,the d.c. conductivity and the activation energies for ZnO films Thin films of ZnO were deposited by spray pyrolysis technique on glass substrates. The thickness of the films (t) was determined using the weighing-method. Crystal structure were investigated by means of a X-ray diffraction XRD, it was found that all films have three peaks located at 2θ ≈ 31.8o, 34.4o and 36.3o with hkl{(100), (002), and (101)} respectively and that the crystallinety increasing with increasing the thickness(t) .The d.c. conductivity for ZnO films has been studied as a function of T for different thicknesses (900, 1400 and 4000 nm) From all samples we noticed that the d.c. conductivity increases with increasing the temperature Also we can be seen the increasing of (σ) with the increasing of film thickness , we noticed the decreasing of activation energies with the increasing of the film thickness.