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Raman scattering study of the a-GeTe structure and possible mechanism for the amorphous-to-crystal transition

K. S. Andrikopoulos·S. N. Yannopoulos·G. A. Voyiatzis·A. V. Kolobov·M. Ribes·J. Tominaga
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Abstract

We report on an inelastic (Raman) light scattering study of the local structure of amorphous GeTe films. A detailed analysis of the temperature-reduced Raman spectra has shown that appreciable structural changes occur as a function of temperature. These changes involve modifications of atomic arrangements such as to facilitate the rapid amorphous-to-crystal transformation, which is the major advantage of phase-change materials used in optical data storage media. A particular structural model, supported by polarization analysis, is proposed being compatible with the experimental data as regards both the structure of a-GeTe and the crystallization transition. The remarkable difference between the Raman spectrum of the crystal and the glass can thus naturally be accounted for.

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K. S. Andrikopoulos, S. N. Yannopoulos, G. A. Voyiatzis, A. V. Kolobov, M. Ribes, J. Tominaga. 2006-02-07. Raman scattering study of the a-GeTe structure and possible mechanism for the amorphous-to-crystal transition. https://doi.org/10.1088/0953-8984%2F18%2F3%2F014

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