Korean Journal of Metals and Materials (대한금속재료학회지)

The Korean Institute of Metals and Materials (대한금속재료학회)
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Surface Morphology Variation During Wet Etching of N-face GaN Using KOH

KOH를 이용한 N-face GaN의 습식 식각으로 인한 표면 변화

  • Kim, Taek-Seung (Department of Materials Science and Metallurgical Engineering, Sunchon National University) ;
  • Han, Seung-Cheol (Department of Materials Science and Metallurgical Engineering, Sunchon National University) ;
  • Kim, Jae-Kwan (Department of Materials Science and Metallurgical Engineering, Sunchon National University) ;
  • Lee, Ji-Myon (Department of Materials Science and Metallurgical Engineering, Sunchon National University)
  • 김택승 (순천대학교 재료금속공학과) ;
  • 한승철 (순천대학교 재료금속공학과) ;
  • 김재관 (순천대학교 재료금속공학과) ;
  • 이지면 (순천대학교 재료금속공학과)
  • Received : 2008.02.20
  • Published : 2008.04.22
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Abstract

Characteristics of etching and induced surface morphology variation by wet-etching of n-face n-type GaN were investigated using KOH solutions. It was observed that hexagonal pyramids were formed on the etched surface regardless of etching conditions. However, the size of the hexagonal pyramids was changed as the etching time and temperature increased, respectively. Initially, as the etching time and concentration of KOH solution increased, the hexagonal pyramid was observed to be dissociated into smaller pyramids. However, as the etching time increased further, the size of the hexagonal pyramids increased again, indicating that the etching of N-face n-type GaN by KOH solutions proceeded through the evolution of hexagonal pyramids, such as formation, dissociation and enlargement of pyramids. Furthermore, it was also observed that there is a correlation between the photoluminescence intensity of the etched surface and the value of root-mean-square roughness. The intensity of PL increased as the roughness value increased due to the enhancement of the extraction efficiency of the generated photons.

Keywords

Acknowledgement

Supported by : 정보통신연구진흥원

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