ALD of scandium oxide from scandium Tris(N,N-'-diisopropylacetamidinate) and water

Sc2O3 films were deposited by atomic layer deposition (ALD) from a new precursor scandium tris(N,N-'-diisopropylacetamidinate) and water. The precursor is thermally stable (> 350 degrees C), volatile, with good reactivity to HF-last silicon. A growth rate of 0.3 A/cycle was obtained at 290 degrees C. The films were pure (C,N < 0.5 atom %) and had a refractive index of 1.8. Reactive ion etching tests on ALD scandia showed an etch rate 18 times slower than ALD hafnia. Electrical measurements showed a high permittivity of similar to 17, and a leakage current density of < 3x10(-3) A/cm(2) for an equivalent oxide thickness of 1.8 nm at 1.0 V. (c) 2006 The Electrochemical Society.