The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
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The Etching Mechanism of $(Ba, Sr)TiO_3$Thin Films in $Ar/CF_4$ High Density Plasma

$Ar/CF_4$ 고밀도 플라즈마에서 $(Ba, Sr)TiO_3$ 박막의 식각 메카니즘

  • 김승범 (현대전자산업(주) 메모리연구소) ;
  • 김창일 (중앙대 전자전기공학부)
  • Published : 2000.05.01
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Abstract

$(Ba, Sr)TiO_3$thin films were etched with a magnetically enhanced inductively coupled plasma (MEICP) at different CF4/Ar gas mixing ratios. Experimental was done by varying the etching parameters such as rf power, dc bias and chamber pressure. The maximum etch rate of the BST films was $1800{AA}/min$ under $CF_4/(CF_4+Ar)$ of 0.1, 600 W/350 V and 5 mTorr. The selectivity of BST to Pt and PR was 0.6, 0.7, respectively. X-ray photoelectron spectroscopy (XPS) results show that surface reaction between Ba, Sr, Ti and C, F radicals occurs during the (Ba, Sr)TiO3 etching. To analyze the composition of surface residue after the etching, films etched with different CF_4/Ar$ gas mixing ratio were investigated using XPS and secondary ion mass spectroscopy (SIMS).

Keywords

References

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