Etching Characteristics of GST Thin Films using Inductively Coupled Plasma of Cl2-Ar Gas Mixtures

Cl2-Ar 혼합가스를 이용한 GST 박막의 유도결합 플라즈마 식각

  • 민남기 (고려대학교 제어계측공학과) ;
  • 김만수 (고려대학교 제어계측공학과) ;
  • ;
  • 김성일 (대전대학교 IT 전자공학과) ;
  • 권광호 (고려대학교 제어계측공학과)
  • Published : 2007.10.01


In this work, the etching characteristics of $Ge_2Sb_2Te_5(GST)$ thin films were investigated using an inductively coupled plasma (ICP) of $Cl_2/Ar$ gas mixture. To analyze the etching mechanism, an optical emission spectroscopy (OES) and surface analysis using X-ray photoelectron spectroscopy (XPS) were carried out. The etch rate of the GST films decreased with decreasing Ar fraction. At the same time, high selective etch rate over $SiO_2$ films was obtained and the selectivity over photoresist films decreased with increasing the he fraction. From XPS results, we found that Te halides were formed at the etching surface and Te halides limited the etch rate of the GST films.



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