Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Optimization of chemical mechanical polishing for bulk AlN single crystal surface

화학적 기계적 연마 공정을 통한 bulk AlN 단결정의 표면 가공

  • Lee, Jung Hun (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Park, Cheol Woo (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Park, Jae Hwa (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Kang, Hyo Sang (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Kang, Suk Hyun (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Lee, Hee Ae (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Lee, Joo Hyung (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • In, Jun Hyeong (Division of Advanced Materials Science and Engineering, Hanyang University) ;
  • Kang, Seung Min (International Graduate School of Design Convergence, Hanseo University) ;
  • Shim, Kwang Bo (Division of Advanced Materials Science and Engineering, Hanyang University)
  • 이정훈 (한양대학교 신소재공학과) ;
  • 박철우 (한양대학교 신소재공학과) ;
  • 박재화 (한양대학교 신소재공학과) ;
  • 강효상 (한양대학교 신소재공학과) ;
  • 강석현 (한양대학교 신소재공학과) ;
  • 이희애 (한양대학교 신소재공학과) ;
  • 이주형 (한양대학교 신소재공학과) ;
  • 인준형 (한양대학교 신소재공학과) ;
  • 강승민 (한서대학교 신소재공학과) ;
  • 심광보 (한양대학교 신소재공학과)
  • Received : 2017.11.21
  • Accepted : 2017.12.13
  • Published : 2018.02.28
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Abstract

To evaluate surface characteristics of AlN single crystal grown by physical vapor transport (PVT) method, chemical mechanical polishing (CMP) were performed with diamond slurry and $SiO_2$ slurry after mechanical polishing (MP), then the surface morphology and analysis of polishing characteristics of the slurry types were analyzed. To estimate how pH of slurry effects polishing process, pH of $SiO_2$ slurry was controlled, the results from estimating the effect of zeta potential and MRR (material removal rate) were compared in accordance with each pH via zeta potential analyzer. Eventually, surface roughness RMS (0.2 nm) could be derived with atomic force microscope (AFM).

PVT법으로 성장된 AlN 단결정의 표면 평탄화 최적화 하기 위하여 기계적 연마 후 $SiO_2$ slurry를 이용한 CMP 공정을 진행하였고 이에 따른 표면 형상, slurry 변화에 따른 가공 특성을 분석하였다. Slurry의 pH가 표면 연마 과정에 미치는 영향을 알아보기 위해 $SiO_2$ slurry의 pH를 조절하였으며, 제타전위측정기를 통해 각각의 pH에 따른 zeta potential의 영향과 MRR(material removal rate) 결과를 비교하였으며, 최종적으로 원자간력 현미경(atomic force microscope)을 이용한 표면 거칠기 RMS(0.2 nm)를 얻을 수 있었다.

Keywords

References

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