한국전자통신학회논문지 (The Journal of the Korea institute of electronic communication sciences)

한국전자통신학회 (Korea Institute of Electronic Communication Science)
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정전용량식 터치스크린 패널을 위한 SiO2 버퍼층 두께에 따른 ITO 박막의 전기적 및 광학적 특성

Electrical and Optical Properties of ITO Thin Films with Various Thicknesses of SiO2 Buffer Layer for Capacitive Touch Screen Panel

  • 정윤근 (전남대학교 기계설계공학과) ;
  • 정양희 (전남대학교 전기 및 반도체공학과) ;
  • 강성준 (전남대학교 전기 및 반도체공학과)
  • 투고 : 2022.09.21
  • 심사 : 2022.12.17
  • 발행 : 2022.12.31
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초록

본 연구에서는 Nb2O5/SiO2 이중 버퍼층위에 ITO박막을 증착하여, SiO2버퍼층 두께 변화 (40~50 nm)에 따른 전기적 및 광학적 특성을 조사하였다. Nb2O5/SiO2 이중 버퍼층을 도입한 ITO박막의 표면 거칠기는 0.815에서 1.181 nm 범위의 작은 값을 가지는 매끄러운 형상을 보였고, 면저항은 99.3~134.0 Ω/sq. 범위로 정전용량식 터치스크린 패널에 적용하는데 문제가 없는 것으로 나타났다. 특히 Nb2O5 (10 nm) / SiO2 (40 nm) 이중 버퍼층을 삽입한 ITO박막의 단파장(400~500 nm) 영역에서의 평균 투과도와 색도(b*)는 83.58 % 와 0.05로 이중버퍼층이 삽입되지 않은 ITO박막의 74.46 % 와 4.28에 비해 상당히 향상된 결과를 나타내었다. 이를 통해 Nb2O5/SiO2 이중 버퍼층을 도입한 ITO박막에서 인덱스 매칭 효과로 인해 단파장 영역의 투과도 및 색도와 같은 광학적 특성이 현저히 향상되었음을 확인할 수 있었다.

In this study, we prepared ITO thin films on the Nb2O5/SiO2 double buffer layer and investigated electrical and optical properties according to the change of SiO2 buffer layer thickness (40~50nm). The ITO thin film fabricated on the Nb2O5/SiO2 double buffer layer exhibited a broad surface roughness with a small value ranging of 0.815 to 1.181nm, and the sheet resistance was 99.3 to 134.0Ω/sq. It seems that there is no problem in applying the ITO thin film to a capacitive touch screen panel. In particular, the average transmittance in the short-wavelength (400~500nm) region and the chromaticity (b*) of the ITO thin film deposited on the Nb2O5(10nm)/SiO2(40nm) double buffer layer showed significantly improved results as 83.58% and 0.05, respectively, compared to 74.46% and 4.28 of ITO thin film without double buffer layer. As a result, it was confirmed that optical properties such as transmittance in the short-wavelength region and chromaticity were remarkably improved due to the index matching effect in the ITO thin film with the Nb2O5/SiO2 double buffer layer.

키워드

참고문헌

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