Phase transformations induced by spherical indentation in ion-implanted amorphous silicon
نویسندگان
چکیده
The deformation behavior of ion-implanted unrelaxed and annealed ion-implanted relaxed amorphous silicon a-Si under spherical indentation at room temperature has been investigated. It has been found that the mode of deformation depends critically on both the preparation of the amorphous film and the scale of the mechanical deformation. Ex situ measurements, such as Raman microspectroscopy and cross-sectional transmission electron microscopy, as well as in situ electrical measurements reveal the occurrence of phase transformations in all relaxed a-Si films. The preferred deformation mode of unrelaxed a-Si is plastic flow, only under certain high load conditions can this state of a-Si be forced to transform. In situ electrical measurements have revealed more detail of the transformation process during both loading and unloading. We have used ELASTICA simulations to obtain estimates of the depth of the metallic phase as a function of load, and good agreement is found with the experiment. On unloading, a clear change in electrical conductivity is observed to correlate with a “pop-out” event on load versus penetration curves. © 2006 American Institute of Physics. DOI: 10.1063/1.2210767
منابع مشابه
Phase transformations induced in relaxed amorphous silicon by indentation at room temperature
The deformation behavior of self-ion-implanted amorphous-Si (a-Si) has been studied using spherical nanoindentation in both relaxed (annealed) and unrelaxed (as-implanted) a-Si. Interestingly, phase transformations were clearly observed in the relaxed state, with the load–unload curves from these samples displaying characteristic discontinuities and cross-sectional transmission electron microsc...
متن کاملEffect of hydrogen on nanoindentation-induced phase transformations in amorphous silicon
The effect of local hydrogen concentration on nanoindentation-induced phase transformations has been investigated in ion-implanted amorphous silicon a-Si . Elevated concentrations of H ranging from 5 1018 to 5 1020 cm−3, over the depth of indentation-induced phase transformed zones have been formed in the a-Si by H ion-implantation. Indentation has been performed under conditions that result in...
متن کاملEffect of oxygen concentration on nanoindentation-induced phase transformations in ion-implanted amorphous silicon
متن کامل
Cyclic microindentations on monocrystalline silicon in air and in water
This paper studies the difference in the mechanical response of monocrystalline silicon to cyclic microindentations in air and in water. It shows that in air the indentations with a spherical indenter generated consequent phase transformations. In the rst indentation cycle, the decomposition featured amorphous phase at low maximum indentation load, Pmax, that was converged to a crystalline co...
متن کاملIn situ spectroscopic study of the plastic deformation of amorphous silicon under non-hydrostatic conditions induced by indentation.
Indentation-induced plastic deformation of amorphous silicon (a-Si) thin films was studied by in situ Raman imaging of the deformed contact region of an indented sample, employing a Raman spectroscopy-enhanced instrumented indentation technique. Quantitative analyses of the generated in situ Raman maps provide unique, new insight into the phase behavior of as-implanted a-Si. In particular, the ...
متن کامل