Influence of the Temperature on GZO Film Deposited by DC Magnetron Reactive Sputtering

Abstract

GZO transparent conductive thin films were deposited by the direct current magnetron sputtering method from a ZnO target doped with Ga2O3 of 3wt% on glass slide substrates under high pressure of argon. The effect of substrate temperature on the GZO film’s morphology, optical and electrical properties is investigated by using scanning electron microscopy (SEM), UV spectrophotometer, four point probe and Spectroscopic Ellipsometer. The results showed that GZO thin films with high quality could be fabricated under the high pressure of argon.When substrate temperature is 250°C or below, surface morphology of thin films can be significantly improved.With the increase of substrate temperature, the crystal grain become larger, the crystal boundaries narrow and become clear, and reach a best case at 250°C. At the same time, the resistivity of GZO thin films decrease and reach the minimum which is 1.099×10-3 Ω•cm at 300°C while the average transmittance increase to 90%. Consequently, the properties of morphology began to get worse with the increase of temperature above 300°C.