Material characterisation of nanowires with intrinsic stress
- Creators
- Mills, S.
- Sader, J. E.
- Boland, J. J.
Abstract
When fabricating nanowires (NWs) in a doubly-clamped beam configuration it is possible for a residual axial stress to be generated. Here, we show that material characterisation of metal and semiconductor NWs subjected to residual axial stress can be problematic. Benchmark measurements of the Young's modulus of NWs are performed by sectioning a doubly-clamped NW into two cantilevered wires, eliminating residual axial stress. Use of models for doubly-clamped beams that incorporate the effects of residual stress are found to lead to ambiguity in the extracted Young's modulus as a function of displacement fit range, even for NWs with no residual stress. This is due to coupling of bending and axial stress effects at small displacements, and the limited displacement range of force curves prior to fracture or plastic deformation. This study highlights the importance of fabricating metal and semiconductor NWs that exhibit little or no residual axial stress for materials characterisation.
Acknowledgement
The authors would like to thank Prof James F Cahoon and David J Hill at the University of North Carolina, Chapel Hill, North Carolina for supplying us with the silicon nanowires used in this work and the staff at the Advanced Microscopy Lab (AML), CRANN, Trinity College Dublin. This publication has emanated from research supported in part by a research grant from Science Foundation Ireland (12/IA/1482), support from the European Research Council under Advanced Grant 321160 and through the generous support of the Naughton Foundation.
Additional details
- ISSN
- 1361-6528
- Science Foundation Ireland
- 12/IA/1482
- European Research Council
- 321160
- Naughton Foundation