Nanoscale mechanical characteristics of vertical ZnO nanowires grown on ZnO:Ga/glass templates

The mechanical properties of vertical single-crystal ZnO nanowires on ZnO:Ga/glass templates were characterized by nanoindentation experiments in this work. The results from x-ray diffraction and Raman spectra show good crystal quality for the ZnO nanowires. The buckling loads were found to be 1465 and 215 μN for ZnO nanowires of 100 and 30 nm diameters, respectively. When the fixed-fixed column mode was used, it was found that the Young's modulus values of the ZnO nanowires of 100 and 30 nm diameters were 117 and 232 GPa, while the critical buckling strains were 0.62% and 0.35%, respectively. On the other hand, when we employed the fixed-pinned column mode, it can be seen that the Young's modulus values were 229 and 454 GPa, while the critical buckling strains were 0.32% and 0.18%, respectively. Buckling behaviour of the ZnO nanowires was significantly predicted by the Euler buckling model in this work.