Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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A Study on the Phase Change Characteristics of Si-doped Ge2Sb2Te5 Thin Films for PRAM

PRAM을 위한 Si-doped Ge2Sb2Te5 박막의 상변화 특성 연구

  • 백승철 (전남대학교 응용화학공학부 촉매연구소) ;
  • 송기호 (전남대학교 응용화학공학부 촉매연구소) ;
  • 이현용 (전남대학교 응용화학공학부 촉매연구소)
  • Published : 2010.04.01
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Abstract

In this paper, we report the changes of electrical, structural and optical characteristics in $Ge_2Sb_2Te_5$ thin films according to an increase of Si content. The Si-doped $Ge_2Sb_2Te_5$ thin films were prepared by rf-magnetron co-sputtering method. Isothermal annealing was carried out at $N_2$ atmosphere. The crystallization speed (v) of amorphous thin films was evaluated by detecting the reflection response signals using a nano-pulse scanner (wavelength = 658 nm) with illumination power of 1~17 mW and pulse duration of 10~460 ns. Structural phase changes were evaluated by XRD, and the optical transmittance was measured in the wavelength range of 300~3000 nm using UV-vis-NIR spectrophotometer. The sheet resistance (RS) of the thin films was measured using 4 point probe. Conclusivlely, the v-value decreased with an increase of Si content, while the RS-values of both crystalline and amorphous phases were increased. In particular, fcc-to-hexagonal transition was suppressed by the added Si atoms.

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References

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