Properties of amorphous tin-doped indium oxide thin films deposited by O2/Ar mixture ion beam-assisted system at room temperature

Highly transparent and conductive thin films of tin-doped indium oxide (ITO) on glass substrates were grown by the ion beam-assisted deposition (IBAD) technique without any substrate heating. X-Ray diffraction investigations indicated that all films have an amorphous structure and no other crystalline phases. The addition of Ar to O2 flow and the increased energy of incident ions were found to reduce the resistivity of the grown films. Observed decrease in the resistivity was attributed to the increase in the carrier concentration. In the optimal growth conditions at room temperature, we obtained the electrical resistivity of 4.6×10−4 Ω-cm, visible transmittance (at λ=550 nm) ≥90%, and optical direct band gap energy of ≅3.75 eV.