Nanoindentation-induced interfacial fracture of ZnO thin films deposited on Si(1Â 1Â 1) substrates by atomic layer deposition

The structural and nanomechanical characteristics of ZnO thin films grown on Si(1 1 1) substrates by using the ALD process are investigated by combining XRD, AFM and Berkovich nanoindentation techniques. Results indicated that the ZnO/Si(1 1 1) thin films also exhibited clear evidences of fracture behaviors-induced pop-in phenomenon in the load-displacement curve during nanoindentation. Moreover, based on the analysis of the energy release in cracking, the fracture toughness of ALD-derived ZnO thin films deposited on Si(1 1 1) substrates is calculated.