Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Ultra-thin aluminum thin films deposited by DC magnetron sputtering for the applications in flexible transparent electrodes

DC 마그네트론 스퍼터링법으로 증착된 초박형 Al 박막의 투명전극 적용성 연구

  • Kim, Daekyun (School of Advanced Materials Engineering, Dong-Eui University) ;
  • Choi, Dooho (School of Advanced Materials Engineering, Dong-Eui University)
  • 김대균 (동의대학교 신소재공학부) ;
  • 최두호 (동의대학교 신소재공학부)
  • Received : 2018.05.03
  • Accepted : 2018.06.27
  • Published : 2018.06.30
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Abstract

In this study, the feasibility of Al-based transparent electrodes for optoelectronic devices was investigated. Al thin films having thickness in the range of 3-12 nm were deposited on glass substrates, and sheet resistance was measured for films thicker than 7 nm and the values continue to decrease with increasing film thickness. The grain size in the films was found to increase with increasing grain size. 85% visible light transmittance was measured at the thickness of 3 nm, and decreased to 50% and 60% when the film thickness reaches 4 nm and 5 nm, respectively. The results of this study can be used in the applications of oxide/metal/oxide type transparent electrodes.

광전소자용 투명전극으로 적용하기 위한 초박형 Al 박막에 대한 기초연구를 수행하였다. 유리 기판 상에 3-12 nm의 두께를 가지는 Al 박막을 형성하였으며, 박막의 두께가 7 nm 이상일 때부터 면저항이 측정되었으며 두께가 증가할 때 면저항이 점진적으로 감소하였다. 박막 내 그레인 크기(Grain size)는 두께가 증가할수록 비례하여 증가하였다. 광 투과도의 경우 가시광선영역(380~770 nm) 파장 기준으로, 3 nm 박막 두께에서 평균 85%의 투과도가 측정된 데 반하여, 4, 5 nm 두께에서 평균 50, 60%로 급격하게 감소되기 시작하며 그 이후 두께 증가에 따라 투과도가 점진적으로 감소하였다. 본 연구결과는 향후 Oxide/Metal/Oxide(OMO) 구조의 고투과, 저저항 투명전극 적용을 위한 기초 결과로 활용될 것으로 기대된다.

Keywords

References

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