New multicomponent transparent conducting oxide films for transparent electrodes of flat panel displays

Multicomponent transparent conducting oxide films with electrical, optical, and chemical properties that varied with the composition were prepared by rf magnetron sputtering. A resistivity as low as 2.8×10−3 Ω cm was obtained for InGaO3 films prepared at substrate temperatures of room temperature and 350 °C. In deposited In2O3–InGaO3–Ga2O3 films, the refractive index gradually decreased and the etching rate in HCl solutions increased as the Ga/(Ga+In) atomic ratio was increased. A resistivity of 7.8×10−4 Ω cm was obtained for a MgIn2O4 film. The etching rate of MgIn2O4 films in HCl solutions increased as the In/(In+Mg) atomic ratio was decreased. In MgIn2O4–Zn2In2O5 films, the etching rate in a 0.2 M HCl solution gradually increased, the refractive index increased, and the band gap decreased as the Zn/(Zn+Mg) atomic ratio was increased. In addition, the transmittance of an InGaO3/Zn2In2O5 multilayer film was slightly improved in comparison with that of only a single layer Zn2In2O5 film.