Abstract
The deformation behavior of both ion-implanted and deposited amorphous Si (a-Si) films has been studied using spherical nanoindentation, followed by analysis using Raman spectroscopy and cross-sectional transmission electron microscopy (XTEM). Indentation was carried out on both unannealed a-Si films (the so-called unrelaxed state) and in ion implanted films that were annealed to 450°C to fully relax the amorphous film. The dominant mode of deformation in unrelaxed films was via plastic flow of the amorphous phase rather than phase transformation, with measured hardness being typically 75-85% of that of crystalline Si. In contrast, deformation via phase transformation was clearly observed in the relaxed state of ion implanted a-Si, with the load-unload curves displaying characteristic discontinuities and Raman and XTEM indicating the presence of high-pressure crystalline phases Si-III and Si-XII following pressure release. In such cases the measured hardness was within 5% of that of the crystalline phase.
| Original language | English |
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| Article number | T6.3/R10.3 |
| Pages (from-to) | 259-264 |
| Number of pages | 6 |
| Journal | Materials Research Society Symposium Proceedings |
| Volume | 843 |
| State | Published - 2005 |
| Externally published | Yes |
| Event | Surface Engineering 2004 - Fundamentals and Applications - Boston, MA, United States Duration: Nov 30 2004 → Dec 2 2004 |