Effects of Annealing on the Characteristics of ATO Films Prepared by Using the RF Magnetron Sputtering Method for Transparent Electrodes

摘要

Antimony (6 wt%) doped tin-oxide (ATO) films to improve conductivity for application to transparent electrodes were deposited on 7059 corning glass by using the RF magnetron sputtering method. The ATO film was deposited at a working pressure of 5 mTorr and RF power of 175 W. The thickness of the deposited ATO films was about 150 nm, which was obtained by using a surface profiler (alpha-step). We investigated the effects of the post-annealing temperature on the structural, electrical and optical properties of the ATO films. The films were annealed at temperatures ranging from 300 °C t o 600 °C in steps of 100 °C in a vacuum ambient by using RTA equipment. X-ray diffraction (XRD) measurements showed the ATO films to be better crystallized with a strong (101) preferred orientation as the annealing temperature increased. The spectra revealed that the annealed films were polycrystalline, retaining the tetragonal rutile structure. The grain size was calculated from XRD spectra by using the Scherrer equation. The electrical resistivity decreased significantly with increasing annealing temperatures up to 600 °C. The ATO film in this work had a Hall mobility of 6.05 cm~a.c-s2V2n dT a hmca13~eri0 e~Ar coT~nceO)((n)tra(tion of 1.74 x 10~( film annealed at temperature of 600 °C showed the lowest resistivity of 5.6 x 10~( Ω--c3m. Th)e optical transmittance increased significantly with increasing annealing temperatures up to 600 °C. The highest transmittance was 90.8 % in the visible range from 400 to 800 nm.