High-k cobalt-titanium oxide (CoTiO3) and nickel-titanium oxide (NiTiO3) were formed by directly oxidizing sputtered Co/Ti and Ni/Ti film. Al/CoTiO3/Si3N4/Si and Al/NiTiO3/Si3N4/Si capacitor structures were fabricated and measured. The effective dielectric constant (k values≅45) with buffer layer for CoTiO3 is larger than that of NiTiO3. In addition, CoTiO3 depicts excellent electrical properties at the same time. This metal oxide thus appears to be a very promising high-k gate dielectric for future ultralarge scale integrated devices.