Size-dependent surface-induced heterogeneous nucleation driven phase-change in Ge2Sb2Te5 nanowires.

Abstract

By combining electron microscopy and size-dependent electrical measurements, we demonstrate surface-induced heterogeneous nucleation-dominant mechanism for recrystallization of amorphous phase-change Ge2Sb2Te5 nanowires. Heterogeneous nucleation theory quantitatively predicts the nucleation rates that vary by 5 orders of magnitude from 190 to 20 nm lengthscales. Our work demonstrates that increasing the surface-to-volume ratio of nanowires has two effects: lowering of the activation energy barrier due to phonon instability and providing nucleation sites for recrystallization. The systematic study of the effect of surface in phase-change behavior is critical for understanding nanoscale phase-transitions and design of nonvolatile memory devices.

DOI: 10.1021/nl801698h

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Cite this paper

@article{Lee2008SizedependentSH, title={Size-dependent surface-induced heterogeneous nucleation driven phase-change in Ge2Sb2Te5 nanowires.}, author={Se-Ho Lee and Yeonwoong Jung and Ritesh Agarwal}, journal={Nano letters}, year={2008}, volume={8 10}, pages={3303-9} }