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

The Korean Institute of Electrical Engineers (대한전기학회)
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A Study on the Characteristics of Silicon Direct Bonding by Hydrogen Plasma Treatment

수소 플라즈마 처리에 의한 실리콘 직접접합 특성에 관한 연구

  • Choe, U-Beom (Dept.of Electrical Engineering, Engineering College, Korea University) ;
  • Ju, Cheol-Min (Dept.of Electrical Engineering, Engineering College, Korea University) ;
  • Kim, Dong-Nam (Dept.of Electrical Engineering, Engineering College, Korea University) ;
  • Seong, Man-Yeong (Dept.of Electrical Engineering, Engineering College, Korea University)
  • Published : 2000.07.01
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Abstract

The plasma surface treatment, using hydrogen gas, of the silicon wafer was investigated as a pretreatment for the application to silicon-on-insulator (SOI) wafers using the silicon direct bonding technique. The chemical reactions of hydrogen plasma with surfaces were used for both the surface activation and the removal of surface contaminants. As a result of exposure of silicon wafer to the plasma, an active oxide layer was formed on the surface, which was rendered hydrophilic. The surface roughness and morphology were estimated as functions of plasma exposing time as well as of power. The surface became smoother with decreased incident hydrogen ion flux by reducing plasma exposing time and power. This process was very effective to reduce the carbon contaminants on the silicon surface, which was responsible for a high initial surface energy. The initial surface energy measured by the crack propagation method was 506 mJ/m2, which was up to about three times higher than that of a conventional RCA cleaning method.

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