Top emission 유기발광적소자 적용을 위한 도핑된 indium tin oxide 박막의 전기적 광학적 특성 연구

Electrical and optical properties of doped indium tin oxide thin films for top emission organic light emission devices

  • 정철호 (성균관대학교 나노과학기술협동학부) ;
  • 강용규 (성균관대학교 신소재공학부) ;
  • 윤대호 (성균관대학교 나노과학기술협동학부, 성균관대학교 신소재공학부)
  • Jung, C.H. (SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University) ;
  • Kang, Y.K. (School of Advanced Materials Science & Engineering, Sungkyunkwan University) ;
  • Yoon, D.H. (SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, School of Advanced Materials Science & Engineering, Sungkyunkwan University)
  • 발행 : 2008.08.31

초록

절연성 및 전도성 12CaO ${\cdot}7Al_2O_3$ (Cl2A7)이 도핑된 ITO 박막을 유리기판 위에 radio frequency(rt) magnetron 스퍼터링 방법으로 절연성 및 전도성 Cl2A7 타겟 칩의 개수를 변화시키면서 증착하였다. 이러한 박막들의 구조적, 전기적, 광학적 특성을 살펴보았다. Cl2A7 타겟 칩의 개수가 증가함에 따라 박막의 캐리어 농도는 감소하고, 비저항은 증가하였다. 박막의 광 투과도는 가시광 영역에서는 80% 이상의 값으로 나타났다. Grain의 크기의 변화는 결정성과 표면 거칠기에 크게 영향을 미친다는 것이 확인되었다.

Insulating and conducting 12CaO ${\cdot}7Al_2O_3$ (Cl2A7)-doped indium tin oxide (ITO) (ITO:Cl2A7 insulator and electride) thin films were deposited on glass substrates by an RF magnetron co-sputtering method with increasing number of insulating and conducting Cl2A7 target chips. The structural, electrical and optical properties of these films were investigated. The carrier concentration decreased and resistivity increased in the films with increasing number of Cl2A7 target chips. The optical transmittance of all of the thin films was above 80 % in the visible wavelength range. The structural property and surface roughness of the films were examined and the decrease of crystallinity and surface roughness was strongly dependent on the change of grain size.

키워드

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