ITO thin films deposited at low temperatures using a kinetic energy controlled sputter-deposition technique

Abstract Low-temperature deposition of tin (Sn)-doped indium oxide (ITO) thin films was attempted using a kinetic energy controlled particle deposition (KECD) technique in which the kinetic energies of sputtered particles along with their incidence angles to the substrate can be controlled in the film forming process. It was expected that this new sputter deposition technique would be able to deposit ITO thin film having a dense structure as well as extremely smooth surfaces even at low substrate temperatures, which would result in the formation of a film having low resistivity. It was found that this method can produce ITO thin films having resistivity as low as 3.5×10 −4 cm and smooth surfaces ( R a ≦0.15 nm) even at temperatures below 50 °C. The sputtering must be performed at a voltage below −100 V, and the sputtering gas pressure in the sputtering source and the oxygen gas pressure during sputtering must be adjusted to an optimal value.