Conference Dates
October 4-9, 2015
Abstract
At ambient temperature and pressure, most of the semiconductor materials are brittle. Traditionally, use of confining pressure via indentation or a hydrostatic confining medium [1, 2] has been required to study the plasticity of such brittle materials. In the case of group IV semiconductors (Diamond, Silicon, and Germanium) the situation is further complicated by pressure-induced phase transformations occurring underneath the indentations. However, previous work has demonstrated that sample miniaturization can also prevent the onset of cracking and allow plastic deformation [3]. Recent advances in in situ instrumentation have enabled micro-compression techniques to extract temperature- and time-dependent deformation parameters [5, 6]. Thus, micro-pillar compression is a promising technique for investigating the plasticity of these semiconductors in their brittle regimes.
Previous work has noted a brittle-ductile transition in Silicon which is dependent on orientation, size, and temperature. This has been tied to transitions between partial and perfect dislocations in III-V semiconductors, but the extreme brittle character of silicon has prevented characterization of plastic flow in the low temperature regimes. In this work, [123]-oriented crystals are utilized to prevent the onset of cracking and allow plastic deformation. Micro-compression is shown to be capable of achieving incredibly high stresses ( >100 GPa), and this is applied to investigate the behavior of the hardest natural material - diamond - and its nearest analog – silicon.
Recommended Citation
[1] B. Kedjar, L. Thilly, J.L. Demenet, J. Rabier, Acta Materialia, 58 (2010) 1426-1440. [2] T. Suzuki, T. Yasutomi, T. Tokuoka, I. Yonenaga, Physica status solidi (a), 171 (1999) 47-52. [3] J. Michler, K. Wasmer, S. Meier, F. Ostlund, K. Leifer, Applied Physics Letters, 90 (2007) 043123-043123. [4] L. Thilly, R. Ghisleni, C. Swistak, J. Michler, Philos. Mag., (2012) 1-11. [5] S. Korte, W.J. Clegg, Scripta Materialia, 60 (2009) 807-810. [6] J.M. Wheeler, C. Niederberger, C. Tessarek, S. Christiansen, J. Michler, International Journal of Plasticity, 40 (2013) 140-151