화학공학소재연구정보센터
Journal of Crystal Growth, Vol.386, 215-219, 2014
Dislocation-density-based modeling of the plastic behavior of 4H-SiC single crystals using the Alexander-Haasen model
To dynamically model the plastic deformation of 4H-SiC single crystals during physical vapor transport (PVT) growth, the Alexander-Haasen model, originally proposed for the elemental semiconductor, is extended into IV-IV compound semiconductors. By fitting the model parameters to the experimental data, we show that the Alexander-Haasen model can describe the plastic deformation of 4H-SiC single crystals if the activation of the carbon-core partial dislocation is modeled in the high-temperature region (above 1000 degrees C) and the silicon-core partial dislocation is modeled in the low-temperature region (below 1000 degrees C). We then apply the same model to the dynamical deformation process of a 4H-SiC single crystal during PVT growth. The time evolution of the dislocation density is shown, and the effects of the cooling time on the final dislocation density, residual stress and stacking faults are also examined. (C) 2013 Elsevier B.V. All rights reserved.