Indium tin oxide films prepared by radio frequency magnetron sputtering method at a low processing temperature

Low temperature deposition of thin films of indium tin oxide (ITO) prepared by radio frequency magnetron sputtering method have been developed. This involved introducing hydrogen into the sputtering gas mixture during the film preparation. The surface morphology of the ITO films was sensitive to the hydrogen partial pressures used in the gas mixture. ITO films with a root mean square roughness of 1.13 nm over an area of 300×300 nm were obtained at the hydrogen partial pressure of 7.0×10⁻⁶ torr. The presence of hydrogen gas in the sputtering processes was also shown to increase the number of charge carriers in the ITO films. At optimal deposition conditions, thin films of ITO with a resistivity of 4.66×10⁻⁴ Ω cm and an optical transmission of over 86% in the visible spectrum range were achieved. The ITO films fabricated by this method do not require substrate heating during the film preparation or any additional post-deposition annealing treatment.