Effects of tin concentration and post-annealing on the electrical and the optical properties of in _2-xSn _xO ₃ (x = 0 ∼ 0.25) deposited at room temperature

Indium-oxide thin films were deposited on glass substrates at room temperature by using a dual oxygen-ion-beam-assisted evaporation system, and the effects of the vacuum annealing conditions on the tin-doping efficiency and on the electrical, the physical, and the optical properties of the films were investigated, The resistivity of pure indium-oxide (10) films increased with annealing temperature while that of tin-doped indium-oxide (ITO) films decreased, The changes in the electrical conductivities of the IO and the ITO films with annealing temperature were due to a decrease in the number of ionized oxygen vacancies and an increase in the ionization probability of neutral tin atom, respectively. Optical transmittances measured using a UV-visible spectrophotometer were higher than 90 % and did not change significantly with annealing temperature, The R MS roughness of the as-deposited films was lower than 1 nm, regardless of the tin percentage, and that after annealing at temperatures below 300°C was lower than 1.2 nm.