Surface-Directed Spinodal Decomposition In Hafnium Silicate Thin Films

Hf distributions in as-grown and annealed (HfO(2))(0.25)(SiO(2))(0.75) films with thicknesses in the range of 4-19 nm were investigated by high-resolution transmission electron microscopy, high angle annular dark field scanning transmission electron microscopy and angle-resolved x-ray photoelectron spectroscopy. Composition waves normal to the film surface were observed providing evidence for surface-directed spinodal decomposition in the pseudobinary (HfO(2))(x)(SiO(2))(1-x) alloy system.