Berkovich nanoindentation on InP

In this study, the pressure-induced deformation mechanisms of single-crystal InP(100) are investigated by using nanoindentation with a Berkovich diamond indenter, micro-Raman spectroscopy and the cross-sectional transmission electron microscopy (XTEM) techniques. The load-displacement curves show the multiple "pop-ins" phenomena during nanoindentation loading. The cracking patterns are found from the scanning electron microscopy (SEM) observations within the mechanically deformed regions. In addition, no evidence of nanoindentation-induced phase transformation is observed up to a maximum indentation load of 200 mN, as revealed from the micro-Raman spectra. Therefore, it is demonstrated that dislocations dominate the deformation mechanisms and, no phase transformation occurs. Form XTEM observations, the slip bands are oriented at an angle of 45, to the sample surface (100), indicating that slip deformation of lnP occurs within the {111} planes. The mechanical deformation processes are observed in InP closely related to the coupling of the dislocation-mediated; plasticity, nucleation and propagation of slip (twinning). (C) 2009 Elsevier B.V. All rights reserved.