Electromigration in Molten-phase Ge2Sb2Te5 and Effects of Doping on Atomic Migration Rate

다국어 초록 (Multilingual Abstract)

Electromigration in molten Ge2Sb2Te5 (GST) was characterized using pulsed DC stress to an isolated line structure. When an electrical pulse was applied to the GST, GST lines were melted by Joule heating, and Ge and Sb atoms migrate to the cathode, whereas Te atoms migrate to the anode. This elemental separation in the molten GST was caused by an electrostatic forceinduced electromigration. The effects of O-, N-, and Bi-doping on the electromigration were also investigated, and atomic mobility changes by the doping were investigated by quantifying DZ* values. The Bi -doping did not affect the DZ* values of the constituent atoms in the molten GST, but the DZ* values decreased by O-doping and N-doping.

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