New multicomponent ZnO-In2O3-SnO2 system and new In4Sn3O12 transparent conducting oxide thin films have been prepared by RF magnetron sputtering. The In4Sn3O12 films, or In2O3-SnO2 films with a Sn/(In + Sn) atomic ratio around 0.5, showed a resistivity of 3-4 x 10(-4) Omega cm and an average transmittance above 80% in the visible range when they were prepared at substrate temperatures of room temperature to 350 degrees C. In addition, the electrical properties of multicomponent Zn2In2O5-ZnSnO3 films changed monotonically as the ZnSnO3 content was varied.