[1] Griffith Univ, Queensland Micro & Nanotechnol Ctr, Nathan, Qld 4111, Australia
[2] Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA
[3] Univ Queensland, Ctr Microscopy & Microanal, St Lucia, Qld 4072, Australia
[4] US Air Force, Res Labs, Mat & Mfg Directorate, Wright Patterson AFB, OH 45433 USA