Electrical properties of Ga2O3-based dielectric thin films prepared by plasma enhanced atomic layer deposition (PEALD)

Ga2O3 and Ga2O3-TiO2 (GTO) nano-mixed thin films were prepared by plasma enhanced atomic layer deposition with an alternating supply of reactant sources, [(CH3)(2)GaNH2](3), Ti(N(CH3)(2))(4) and oxygen plasma. The uniform and smooth Ga2O3 and GTO thin films were successfully deposited. Excellent step coverage of these films was obtained by chemisorbed chemical reactions with oxygen plasma on the surface. The dielectric constant of GTO thin film definitely increased compared to Ga2O3 film, and the leakage currents of GTO films were comparable to Ga2O3 films. The leakage current density of a 40-nm-GTO film annealed at 600 degrees C was approximately 1 x 10(-7) A/cm(2) up to about 600 kV/cm.