Current Photovoltaic Research

Korea Photovoltaic Society (한국태양광발전학회)
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Effect of Ag Alloying on Device Performance of Flexible CIGSe Thin-film Solar Cells Using Stainless Steel Substrates

  • Awet Mana Amare (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Inchan Hwang (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Inyoung Jeong (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Joo Hyung Park (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Jin Gi An (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Soomin Song (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Young-Joo Eo (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Ara Cho (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Jun-Sik Cho (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Seung Kyu Ahn (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Jinsu Yoo (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • SeJin Ahn (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Jihye Gwak (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Hyun-wook Park (Department of Energy Engineering, Korea Institute of Energy Technology) ;
  • Jae Ho Yun (Department of Energy Engineering, Korea Institute of Energy Technology) ;
  • Kihwan Kim (Photovoltaics Research Department, Korea Institute of Energy Research (KIER)) ;
  • Donghyeop Shin (Photovoltaics Research Department, Korea Institute of Energy Research (KIER))
  • Received : 2023.02.10
  • Accepted : 2023.03.20
  • Published : 2023.03.31
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Abstract

In this work, we investigated the thickness of Ag precursor layer to improve the performance of flexible CIGSe solar cells grown on stainless steel (STS) substrates through three-stage co-evaporation with Ga grading followed by alkali treatments. The small amount of incorporated Ag in CIGSe films showed enhancement in the grain size and device efficiency. With an optimal 6 nm-thick Ag layer, the best cell on the STS substrate yielded more than 16%, which is comparable to the soda-lime glass (SLG) substrate. Thus, the addition of controlled Ag combined with alkali post-deposition treatment (PDT) led to increased open-circuit voltage (VOC), accompanied by the increased built-in potential as confirmed by capacitance-voltage (C-V) measurements. It is related to a reduction of charge recombination at the depletion region. The results suggest that Ag alloying and alkali PDT are essential for producing highly efficient flexible CIGSe solar cells.

Keywords

Acknowledgement

This research was financially supported by the Korea Institute of Energy Research (KIER) (grant no. C3-2401, 2402, 2403) and the National Research Foundation (grant no. 2022M3J1A1063019) funded by the Ministry of Science and ICT.

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