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

The Korea Association of Crystal Growth (한국결정성장학회)
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The effects of Mg impurities on β-Ga2O3 thin films grown by MOCVD

MOCVD로 성장한 β-Ga2O3 박막에 대한 Mg 불순물 주입 효과

  • Park, Sang Hun (Department of Materials Engineering, Korea Maritime and Ocean University) ;
  • Lee, Seo Young (Department of Materials Engineering, Korea Maritime and Ocean University) ;
  • Ahn, Hyung Soo (Department of Materials Engineering, Korea Maritime and Ocean University) ;
  • Yu, Young Moon (LED-Marine Convergence Technology R&BD Center, Pukyong National University) ;
  • Yang, Min (Department of Materials Engineering, Korea Maritime and Ocean University)
  • 박상훈 (한국해양대학교 전자소재공학과) ;
  • 이서영 (한국해양대학교 전자소재공학과) ;
  • 안형수 (한국해양대학교 전자소재공학과) ;
  • 유영문 (부경대학교 LED-해양융합기술센터) ;
  • 양민 (한국해양대학교 전자소재공학과)
  • Received : 2018.01.02
  • Accepted : 2018.02.06
  • Published : 2018.04.30
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Abstract

In this study, we investigated the impurity effect of $Ga_2O_3$ doped thin film by simple doping method using Mg acetate solution. Both undoped $Ga_2O_3$ thin films and Mg-doped $Ga_2O_3$ thin films were grown on Si substrates at 600 and $900^{\circ}C$ for 30 minutes by means of a customized MOCVD method. As a result of the surface analysis, there were no obvious morphological differences by Mg impurity implantation. The surface of the thin film grown at $900^{\circ}C$ was rougher than those grown at $600^{\circ}C$ and polycrystallization was achieved. As a result of the optical property analysis, in the case of the doped sample, the overall emission peak was red shifted and the UV radiation intensity was increased. As a result of the I-V curve, the leakage current of the $600^{\circ}C$ growth thin film decreased by the Mg impurity and the photocurrent of the growth thin film of $900^{\circ}C$ increased.

본 연구에서는 Mg acetate 수용액을 사용한 간편한 도핑방법으로 불순물을 주입하여 성장한 $Ga_2O_3$ 박막의 불순물 주입 효과에 대해 연구하였다. MOCVD 방법을 이용해 Si 기판 위에 undoped $Ga_2O_3$ 박막과 Mg-doped $Ga_2O_3$ 박막을 각각 $600^{\circ}C$와 $900^{\circ}C$의 성장온도에서 30분간 성장하였다. 표면 형상 분석 결과 Mg 불순물 주입에 따른 큰 차이는 확인되지 않았으며 $900^{\circ}C$에서 성장한 박막의 표면이 $600^{\circ}C$에서 성장한 박막의 표면보다 큰 거칠기를 가지고 다결정화 되는 것을 확인하였다. 광학적 특성 분석 결과, 도핑된 샘플의 경우 전체적인 발광 피크가 red shift 되었고 UV 방출 세기가 커지는 특성을 보였다. I-V 측정 결과로부터 Mg 불순물에 의해 $600^{\circ}C$ 성장 박막의 누설전류가 감소하고, $900^{\circ}C$ 성장 박막의 광전류는 증가하는 효과를 확인하였다.

Keywords

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