Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Effect of Indium Zinc Oxide Transparent Electrode on Power Conversion Efficiency of Flexible Dye-Sensitized Solar Cells

플렉시블 염료 감응형 솔라셀의 효율에 미치는 Indium Zinc Oxide 투명전극의 영향

  • Lee, Do Young (Department of Chemical Engineering, Inha University) ;
  • Chung, Chee Won (Department of Chemical Engineering, Inha University)
  • 이도영 (인하대학교 화학공학과) ;
  • 정지원 (인하대학교 화학공학과)
  • Received : 2008.10.09
  • Accepted : 2008.12.23
  • Published : 2009.02.28
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Abstract

IZO thin films have been deposited on poly(ethylene terephthalate) flexible substrate under varying radio frequency (rf) power, process pressure and thickness of IZO films using rf magnetron sputtering under $Ar/O_2$ gas mix. As the process pressure increased, the deposition rate was slightly increased and the transmittance showed little change, but the resistivity was increased. With increasing rf power, the great increase in deposition rate was observed but the transmittance showed a slight change only, and the resistivity was decreased. In addition, an attempt was made to find the optimal thickness of IZO films under varying the thickness of IZO films at the process conditions of 1 mTorr pressure and 90 W rf power, which showed lowest resistivity. IZO thin films with the thickness of $1,500{\AA}$ showed lowest resistivity and also showed highest transmittance around the wavelength zone of the maximum absorption. The power conversion efficiency of solar cells fabricated using various transparent electrodes with different thicknesses were measured and the solar cell with IZO electrode of $1,500{\AA}$ showed the maximum conversion-efficiency of 2.88 %.

Indium zinc oxide($In_2O_3-ZnO$, IZO) 박막이 poly(ethylene terephthalate) 플렉시블 기판위에 rf 마그네트론 스퍼터링을 이용하여 $Ar/O_2$ 혼합 가스하에서 rf power, 공정압력 및 IZO 두께를 변화하여 증착되었다. 공정압력이 증가됨에 따라서 증착속도는 약간씩 증가되었고 투과도에는 거의 변화가 없었으나 저항도는 증가되었다. rf power의 증가에 대하여는 증착속도가 크게 증가하였고 투과도는 미소한 변화를 보였으며 저항도는 최저점을 보인 후에 증가하였다. 가장 낮은 저항을 보인 1 mTorr와 90 W의 공정조건에서 IZO 박막의 두께변화를 실시하여 최적의 두께를 찾고자 하였다. $1,500{\AA}$ 두께의 IZO 박막이 가장 낮은 저항도를 나타냈고 염료의 최대흡수 파장영역 주변에서 높은 투과도를 보였다. 두께가 다른 투명전극들을 이용하여 제조된 태양전지의 에너지 변환효율을 측정한 결과, $1,500{\AA}$ 두께의 IZO 전극을 사용한 셀에서 2.88%의 최대 변환효율을 보였다.

Keywords

References

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