An Investigation into the Effect of Gd on the Optoelectronic Properties of Znowaveguide Thin Films by Prism Coupler

GdxZn1-xO (x=0, 0.005, 0.01, 0.02, 0.04) films were elaborated via spray pyrolysis on ordinary glass. XRD showed the incorporation of Gd in wurtzite structure with decreasing crystallite size and a pronounced alignment along the [002] direction. The first derivative based on UV-Vis measurements demonstrated the increase in the optical gap energy. Electrical properties of the films were investigated through the Hall effect technique which indicated a decrease in the charge carriers’ density, an increase in the mobility and magnetoresistance. Photoluminescence spectra of the films revealed the presence of different kinds of point defect with a slight tendency of promoting Zni and VO defects. AFM assessments depicted randomly oriented and elongated grains over Gd doping and an overall smoother films. The waveguide properties of the films were investigated using the prism coupler techniques, where a slight general decrease in both refractiveindices with a birefringence inversion was observed. The simulated results were highly aligned with the prism coupler model of distinct interfaces and step refractive index.