%0 Journal Article
%T Dislocation Energetics and Pop-Ins in AlN Thin Films by Berkovich Nanoindentation
%A Sheng-Rui Jian
%A Yu-Chin Tseng
%A I-Ju Teng
%A Jenh-Yih Juang
%J Materials
%D 2013
%I MDPI AG
%R 10.3390/ma6094259
%X Nanoindentation-induced multiple pop-ins were observed in the load-displacement curves when the mechanical responses of AlN films grown on c-plane sapphire substrates were investigated by using Berkovich indenters. No evidence of phase transformation is revealed by cross-sectional transmission electron microscopy (XTEM) and selected area diffraction (SAD) analyses. Instead XTEM observations suggest that these ¡°instabilities¡± resulted from the sudden nucleation of dislocations propagating along the slip systems lying on the {0001} basal planes and the £¿pyramidal planes commonly observed in hexagonal compound semiconductors. Based on this scenario, an energetic estimation of dislocation nucleation is made.
%K nanoindentation
%K pop-ins
%K AlN thin films
%K transmission electron microscopy
%U http://www.mdpi.com/1996-1944/6/9/4259