Local Epitaxial Growth of Ru Thin Films by Atomic Layer Deposition at Low Temperature

This study demonstrated that atomic layer deposition (ALD) is a promising deposition method for the epitaxial growth of Ru thin films on lattice matched metal film substrates. Ru films were grown on face centered cubic metal substrates using 2,4-(dimethylpentadienyl)(ethylcyclopentadienyl) Ru and O-2. Despite the low growth temperature (210 degrees C), highly (002) oriented local epitaxial Ru films were formed on highly (111) oriented Pt and Au substrates due to the structural compatibility between the (111) plane of the Pt and Au substrates and the (002) plane of Ru. The Ru films on Pt substrates showed better epitaxial properties than those on Au substrates because of the smaller lattice mismatch between (111) Pt and (002) Ru (2.52%, 6.59% for the case of Au). The highly (002) oriented local epitaxial Ru films showed a lower growth rate than the more randomly oriented films. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3596018] All rights reserved.