Journal of the Korean Ceramic Society (한국세라믹학회지)

The Korean Ceramic Society (한국세라믹학회)
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Evaluation of Phase Transition Behavior of Ge2Sb2Te5 Thin Film for Phase Change Random Access Memory

상변환 메모리의 응용을 위한 Ge2Sb2Te5 박막의 상변환 거동 평가

  • Do, Woo-Hyuk (Department of Ceramic Engineering, Yonsei University) ;
  • Kim, Sung-Soon (Department of Ceramic Engineering, Yonsei University) ;
  • Bae, Jun-Hyun (Department of Ceramic Engineering, Yonsei University) ;
  • Cha, Jun-Ho (Department of Ceramic Engineering, Yonsei University) ;
  • Kim, Kyung-Ho (Department of Ceramic Engineering, Yonsei University) ;
  • Lee, Young-Kook (Department of Metallurgical Engineering, Yonsei University) ;
  • Lee, Hong-Lim (Department of Ceramic Engineering, Yonsei University)
  • 도우혁 (연세대학교 세라믹공학과) ;
  • 김성순 (연세대학교 세라믹공학과) ;
  • 배준현 (연세대학교 세라믹공학과) ;
  • 차준호 (연세대학교 세라믹공학과) ;
  • 김경호 (연세대학교 세라믹공학과) ;
  • 이영국 (연세대학교 금속시스템공학과) ;
  • 이홍림 (연세대학교 세라믹공학과)
  • Published : 2007.01.31
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Abstract

The phase transition behavior of $Ge_2Sb_2Te_5$ (GST) thin film, which is a candidate material of recording layer for phase change random access memory (PRAM), has been evaluated using an in-situ reflectance measurement method. The experimental data have been analyzed by using johnson-mehl-avrami-kolomogorov (JMAK) model. JMAK model can be used only in isothermal state. However, temperature changes with time during the operation of PRAM. To apply JMAK equation to PRAM simulation, it has been assumed that the temperature increases stepwise and isothermally. By using JMAK equation and assumption for the transient state, the phase transition behavior of GST thin film has been predicted under $3^{\circ}C/min$ heating rate in this study. The simulation result agrees well with the experimental results. Therefore, It can be concluded that JMAK equation can be used far the PRAM simulation model.

Keywords

References

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