Oliver, D. J.Bradby, J. E.Ruffell, S.Williams, J. S.Munroe, P.2015-10-222015-10-220021-8979http://hdl.handle.net/1885/16029We have investigated nanoindentation-induced plastic deformation in amorphousgermanium (a-Ge) prepared by high-energy self-ion implantation. Using cross-sectional transmission electron microscopy, micro-Raman spectroscopy, and force-displacement curve analysis, we find strong evidence for a pressure-induced metallic phase transformation during indentation. Crystalline diamond-cubic Ge-I is observed in residual indents. Relaxed and unrelaxed structural states of a-Ge exhibit similar behavior on loading, but transform at different pressures on unloading. Both forms are markedly softer mechanically than crystalline Ge. These results assist in furthering the understanding of the intriguing phenomenon known as “explosive crystallization.”We thank the Australian Research Council for funding support.http://www.sherpa.ac.uk/romeo/issn/0021-8979..."Publishers version/PDF may be used on author's personal website, institutional website or institutional repository" from SHERPA/RoMEO site (as at 22/10/15). Copyright 2009 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics and may be found at https://doi.org/10.1063/1.3255999Keywords: Amorphous germanium; Cross sectional transmission electron microscopy; Crystalline Ge; Explosive crystallizations; Force-displacement curves; High energy; Induced phase transformation; Metallic phase; Micro Raman Spectroscopy; Residual indent; Self-ion im2009-11-0610.1063/1.32559992016-02-24