Cl2/Ar 유도 결합 플라즈마를 이용한 NiFe, NiFeCo, Ta의 건식식각

Dry Etching of NiFe, NiFeCo, and Ta in Cl2/Ar Inductively Coupled Plasma

  • 라현욱 (전북대학교 화학공학부, 나노소재공정연구센터) ;
  • 박형조 (나리지온) ;
  • 김기주 (전북대학교 화학공학부, 나노소재공정연구센터) ;
  • 김완영 (전북대학교 화학공학부, 나노소재공정연구센터) ;
  • 한윤봉 (전북대학교 화학공학부, 나노소재공정연구센터)
  • Ra, Hyun-Wook (Nanomaterials Processing Research Center and School of Chemical Engineering and Technology, Chonbuk National University) ;
  • Park, HyungJo (Knowledge on Inc.) ;
  • Kim, Ki Ju (Nanomaterials Processing Research Center and School of Chemical Engineering and Technology, Chonbuk National University) ;
  • Kim, Wan-Young (Nanomaterials Processing Research Center and School of Chemical Engineering and Technology, Chonbuk National University) ;
  • Hahn, Yoon-Bong (Nanomaterials Processing Research Center and School of Chemical Engineering and Technology, Chonbuk National University)
  • 투고 : 2004.02.12
  • 심사 : 2004.10.15
  • 발행 : 2005.02.28

초록

Magnetic random access memory(MRAM) 소자재료로 사용되고 있는 NiFe, NiFeCo, Ta 등의 박막을 $Cl_2/Ar$ 유도 결합 플라즈마를 이용하여 식각하였다. NiFe와 NiFeCo의 식각 속도는 특정 ICP 공급 전력에서 최대값을 나타냈지만, Ta의 식각 속도는 ICP 공급 전력이 증가함에 따라 증가하였다. RF 하부전극 전력이 증가하면서 자성박막의 식각 속도는 증가하였지만, 공정압력과 $Cl_2$의 농도가 증가함에 따라 점진적으로 감소하였다. 식각 후에 염소에 의한 표면 부식을 방지하기 위해 이온수로 5분간 세척하였다. 식각 프로파일은 $Cl_2$ 농도가 50%일 경우에 식각 단면에 식각 잔유물들이 존재하지 않는 부드러운 단면을 얻을 수 있었다.

Dry etching of NiFe, NiFeCo, and Ta for magnetic random access memory (MRAM) by inductively coupled plasmas (ICPs) of $Cl_2/Ar$ has been carried out. NiFe and NiFeCo showed maximum etch rates at a particular ICP source power, but the etch rate of Ta increased with the ICP source power. The etch rates of the magnetic thin films increased with the RF chuck power, but decreased with the operating pressure and the $Cl_2$ concentration. To avoid a corrosion problem by chlorine, the etched samples were rinsed with de-ionized water for 5 minutes after etching. The etch profile showed a clean and smooth surface at 50% $Cl_2$ concentration.

키워드

참고문헌

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