Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Etch Characteristics of Magnetic Tunnel Junction Stack Patterned with Nanometer Size for Magnetic Random Access Memory

자성 메모리의 적용을 위한 나노미터 크기로 패턴된 Magnetic Tunnel Junction의 식각 특성

  • Park, Ik Hyun (Department of Chemical Engineering and Institute of Clean Technology, Inha University) ;
  • Lee, Jang Woo (Department of Chemical Engineering and Institute of Clean Technology, Inha University) ;
  • Chung, Chee Won (Department of Chemical Engineering and Institute of Clean Technology, Inha University)
  • 박익현 (인하대학교 화학공학과 청정기반기술연구소) ;
  • 이장우 (인하대학교 화학공학과 청정기반기술연구소) ;
  • 정지원 (인하대학교 화학공학과 청정기반기술연구소)
  • Received : 2005.10.07
  • Accepted : 2005.10.27
  • Published : 2005.12.10
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Abstract

Inductively coupled plasma reactive ion etching of magnetic tunnel junction (MTJ) stack, which is one of the key elements in magnetic random access memory, was studied. The MTJ stacks were patterned in nanometer size by electron(e)-beam lithography, and TiN thin films were employed as a hard mask. The etch process of TiN hard mask was examined using Ar, $Cl_2/Ar$, and $SF_6/Ar$. The TiN hard mask patterned by e-beam lithography was first etched and then the etching of MTJ stack was performed. The MTJ stacks were etched using Ar, $Cl_2/Ar$, and $BCl_3/Ar$ gases by varying gas concentration and pressure.

자성 메모리반도체의 핵심 소자인 magnetic tunnel junction (MTJ) stack에 대한 고밀도 유도결합 플라즈마 반응성 식각이 연구되었다. MTJ stack은 electron(e)-beam lithography 공정을 사용하여 나노미터 크기의 패턴 형성이 되었으며 식각을 위한 하드 마스크(hard mask)로서 TiN 박막이 이용되었다. TiN 박막은 Ar, $Cl_2/Ar$, 그리고 $SF_6/Ar$들의 가스를 사용하여 식각공정이 연구되었다. E-beam lithography로 패턴된 TiN/MTJ stack은 첫 번째 단계로 TiN 하드 마스크가 식각되고 두 번째로 MTJ stack이 식각되어 완성되었다. MTJ stack은 Ar, $Cl_2/Ar$, $BCl_3/Ar$을 이용하여 식각되었으며 각각의 가스농도와 가스 압력을 변화시켜 MTJ stack의 식각특성이 조사되었다.

Keywords

Acknowledgement

Supported by : 청정기반기술연구소

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