Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Electromigration in Molten-phase Ge2Sb2Te5 and Effects of Doping on Atomic Migration Rate

  • Joo, Young-Chang (Department of Materials Science & Engineering, Seoul National University) ;
  • Yang, Tae-Youl (Department of Materials Science & Engineering, Seoul National University) ;
  • Cho, Ju-Young (Department of Materials Science & Engineering, Seoul National University) ;
  • Park, Yong-Jin (Department of Materials Science & Engineering, Seoul National University)
  • Received : 2011.12.27
  • Accepted : 2012.01.09
  • Published : 2012.01.31
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Abstract

Electromigration in molten $Ge_2Sb_2Te_5$ (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 force-induced 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 D$DZ^*$ values decreased by O-doping and N-doping.

Keywords

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