Effects of Oxygen Flow Rate on Optoelectronic Characteristics of SnO2 Thin Films for Application to Optical Sensors

In this study, tin oxide (SnO 2 ) thin films were deposited on glass substrates by RF magnetron sputtering, with process parameters optimized by adjusting the oxygen flow rate.Subsequently, thermal treatment was performed at various temperatures in a vacuum environment.The thickness, electrical conductivity, optical transmittance, and figure of merit (FOM) of the films were analyzed.The results indicate that the films deposited with an oxygen flow rate of 5 sccm, a sputtering power of 80 W, and a deposition time of 30 min, followed by annealing at 200 ℃, exhibited the highest performance.Specifically, the films achieved a minimum resistivity of 3.19 × 10 -2 Ω•cm and an optimal FOM of 7.43 × 10 -5 Ω -1 .These findings demonstrate excellent optoelectronic properties, suggesting high potential for applications in optoelectronic sensor materials.