Current Photovoltaic Research

Korea Photovoltaic Society (한국태양광발전학회)
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Performance Variation of Cu(In,Ga)Se2 Photovoltaic Absorber Post-deposition Treated with Different KF Thickness

다양한 두께의 KF로 후증착열처리된 Cu(In,Ga)Se2 광흡수층의 태양전지 성능 변화

  • Bae, Jin A (Department of Chemical engineering, Yeungnam University) ;
  • Song, Yu Jin (Department of Chemical engineering, Yeungnam University) ;
  • Jeon, Chan Wook (Department of Chemical engineering, Yeungnam University)
  • 배진아 (화학공학과, 영남대학교) ;
  • 송유진 (화학공학과, 영남대학교) ;
  • 전찬욱 (화학공학과, 영남대학교)
  • Received : 2018.06.04
  • Accepted : 2018.06.11
  • Published : 2018.06.30
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Abstract

In this study, CIGS absorber layers were deposited on low-alkali glass and sodalime glass substrates and potasium floride (KF) of various thicknesses was supplied at an elevated temperature after the CIGS growth. The effect of KF post-deposition treatment on the two types of substrates was extremely different. On the low-alkali substrate, the open-circuit voltage (Voc) was improved but the fill-factor (FF) degradation was severe, whereas the sodalime substrate showed Voc deterioration and FF improvement. In the case of supplying 20 nm of KF on both substrates, the efficiency gain of 0.3~1.1%p was obtained. With increasing the KF thickness, a small protrusion-like microstructure developed on the surface of the absorber layer, and the microstructures that were not removed in the subsequent process were found to be the main cause of the FF loss.

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References

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