Successful deposition and mechanical probing of nearly spherical, defect-free silicon nanospheres has been accomplished. The results show silicon at this length scale to be up to four times harder than bulk silicon. Detailed measurements of plasticity evolution and the corresponding hardening response in normally brittle silicon is possible in these small volumes. Based upon a proposed length scale related to the size of nanospheres in the 20-50 nm radii range, a prediction of observed hardnesses in the range of 20-50 GPa is made. The ramifications of this to computational materials science studies on identical volumes are discussed.
Bibliographical noteFunding Information:
This work was supported by the National Science Foundation under grant DMI-0103169 and an NSF-IGERT program through grant DGE-0114372 and the USDOE Office of Science.
- A. Dislocations
- A. Indentation and hardness
- A. Strengthening and mechanisms