This chapter reviews what is currently known about the atomic structure of Ge-Sb-Te phase-change materials in the amorphous phase. An introduction is first given to aspects of structural order in amorphous solids at different length scales, and brief reviews of experimental techniques for structure determination and of computer-simulation methods are outlined. A discussion is then given of the available experimental data on the structure of Ge-Sb-Te amorphous solids, primarily Ge2Sb2Te5, together with the results of various computer-simulation studies of these materials.
KeywordsPair Distribution Function EXAFS Data Reverse Monte Carlo First Sharp Diffraction Peak Wrong Bond
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