Preparation and characterization of transparent conductive zinc doped tin oxide thin films prepared by radio-frequency magnetron sputtering

Abstract

High transparent and conductive thin films of zinc doped tin oxide (ZTO) were deposited on quartz substrates by the radio-frequency (RF) magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO₂ ceramic target. The effect of substrate temperature on the structural, electrical and optical performances of ZTO films has been studied. X-ray diffraction (XRD) results show that ZTO films possess tetragonal rutile structure with the preferred orientation of (101). The surface morphology and roughness of the films was investigated by the atomic force microscope (AFM). The electrical characteristic (including carrier concentration, Hall mobility and resistivity) and optical transmittance were studied by the Hall tester and UVVIS, respectively. The highest carrier concentration of −1.144×10²⁰ cm⁻³ and the Hall mobility of 7.018 cm²(V · sec)⁻¹ for the film with an average transmittance of about 80.0% in the visible region and the lowest resistivity of 1.116×10⁻² Ω·cm were obtained when the ZTO films deposited at 250 °C.

Keywords

radio-frequency (RF) magnetron sputtering / transparent conducting film / zinc doped tin oxide (ZTO) / substrate temperature

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