The high pressure phase transformation behavior of silicon nanowires
- Australian National Univ., Canberra, ACT (Australia). Research School of Physics and Engineering
- Vienna Univ. of Technology (Austria). Inst. for Solid State Electronics
Si nanowires of 80–150 nm and 200–250 nm diameter are pressurized up to 22 GPa using a diamond anvil cell. Raman and x-ray diffraction data were collected during both compression and decompression. Electron microscopy images reveal that the nanowires retain a nanowire-like morphology (after high pressure treatment). On compression, dc-Si was observed to persist at pressures up to 19 GPa compared to ~11 GPa for bulk-Si. On decompression, the metallic β-Sn phase was found to be more stable for Si nanowires compared with bulk-Si when lowering the pressure and was observed as low as 6 GPa. For the smallest nanowires studied (80–150 nm), predominately a-Si was obtained on decompression, whereas for larger nanowires (200–250 nm), clear evidence for the r8/bc8-Si phase was obtained. We suggest that the small volume of the individual Si nanowires compared with bulk-Si inhibits the nucleation of the r8-Si phase on decompression. This study shows that there is a size dependence in the high pressure behavior of Si nanowires during both compression and decompression.
- Research Organization:
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- AC02-06CH11357; FG02-94ER14466; FG02-99ER45775; NA0001974
- OSTI ID:
- 1474160
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 12 Vol. 113; ISSN 0003-6951
- Publisher:
- American Institute of Physics (AIP)Copyright Statement
- Country of Publication:
- United States
- Language:
- ENGLISH