Structural and Electrical Properties of Fluorine doped Tin oxide (FTO) Thin Film Deposited by Spin Coating Technique

Abstract

Fluorine-Doped Tin OxideTO) thin films were deposited on a glass substrate using the spin coating technique and then annealed in both open air and nitrogen environments at temperatures between 500^oC and 600°C. This study examined how annealing temperature affects the structural and electrical properties of the films. X-ray diffraction (XRD) analysis showed that the films had a polycrystalline structure, predominantly with the (110) plane. As the annealing temperature is increased, the crystal size also increased, leading to lower dislocation density and higher electron mobility. The resistivity of the films decreased with higher annealing temperatures, reaching its lowest value at 600°C. These findings indicate that annealing temperature is crucial for optimizing the structural and electrical properties of FTO thin films made via spin coating. The optimal annealing conditions were found to be 600°C in open air, resulting in a resistivity of 2.47×10^-3 Ω-cm, sheet resistance of 1.08×10^-2 Ω/square, the largest grain size of 18.41 nm, and the lowest values for dislocation density (2.95×10¹⁵ lines/cm²) and micro-strain (1.97×10^-3).