Behavior of Surface Compositions in CMP Process for PZT Thin Fims

PZT 박막의 CMP 공정중 표면 조성 거동

  • Ko, Pil-Ju (Dept. of Electrical Eng., Chosun University) ;
  • Kim, Nam-Hoon (Research Institute of Energy Resources Technology, Chosun University) ;
  • Lee, Woo-Sun (Dept. of Electrical Eng., Chosun University)
  • 고필주 (조선대학교 전기공학과) ;
  • 김남훈 (조선대학교 에너지자원신기술연구소) ;
  • 이우선 (조선대학교 전기공학과)
  • Published : 2006.07.12

Abstract

Pb(Zr,Ti)$O_3$ is one of the most attractive ferroelectric materials for realizing the FeRAM due to its higher remanant polarization and the ability to withstand higher coercive fields. Generally, the ferroelectric materials were patterned by a plasma etching process for high-density FeRAM. The applicable possibility of CMP process to pattern Pb(Zr,Ti)$O_3$ instead of plasma etching process was investigated in our previous study for improvement of an angled sidewall which prevents the densification of ferroelectric memory and is apt to receive the plasma damage. Our previous study showed that good removal rate with the excellent surface roughness compared to plasma etching process were obtained by CMP process for the patterning of Pb(Zr,Ti)$O_3$. The suitable selectivity to TEOS without any damage to the structural property of Pb(Zr,Ti)$O_3$ was also guaranteed. In this study, the removal mechanism of $Pb_{1.1}(Zr_{0.52}Ti_{0.48})O_3$ coated by sol-gel method was investigated. Surface analysis of polished specimens at the best and worst conditions was carried out by XPS.

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