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2021 Vol.9, Issue 3 Preview Page
Secondary Phase and Defects in Cu2ZnSnSe4 Solar Cells with Decreasing Absorber Layer Thickness
Young-Ill Kim1
,
Dae-Ho Son12
,
Jaebaek Lee12
,
Shi-Joon Sung12
,
Jin-Kyu Kang12
,
Dae-Hwan Kim12*
,
Kee-Jeong Yang12**
1Research Center for Thin Film Solar Cells, DGIST, Daegu 42988, Korea
2Division of Energy Technology, DGIST, Daegu 42988, Korea
*Corresponding Author
**Corresponding Author
30 September 2021. pp. 84-95
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Abstract

The power conversion efficiency of Cu2ZnSnSe4 (CZTSe) solar cells depends on the absorber layer thickness; however, changes in the characteristics of the cells with varying absorber layer thickness are unclear. In this study, we investigated the changes in the characteristics of CZTSe solar cells for varying absorber layer thickness. Five absorber thicknesses were employed: CZTSe1 2.78 μm, CZTSe2 1.01 μm, CZTSe3 0.55 μm, CZTSe4 0.29 μm, and CZTSe5 0.15-0.23 μm. The efficiency of the CZTSe solar cells decreased as the absorber thickness decreased, resulting in power conversion efficiencies of 10.45% (CZTSe1), 8.67% (CZTSe2), 7.14% (CZTSe3), 3.44% (CZTSe4), and 1.54% (CZTSe5). As the thickness of the CZTSe absorber layer decreased, the electron-hole recombination at the grain boundaries and the absorber-back-contact interface increased. This caused an increase in the current loss, owing to light loss in the long-wavelength region. In addition, as the thickness of the CZTSe absorber layer decreased, more ZnSe was produced, and the resulting defects and defect clusters led to an open-circuit voltage loss.

Keywords
CZTSe
Thin-film solar cell
Ultrathin absorber
Secondary phase
Open circuit voltage deficit
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 9
  • No :3
  • Pages :84-95
  • Received Date : 2021-04-13
  • Revised Date : 2021-04-23
  • Accepted Date : 2021-04-25
  • DOI :https://doi.org/10.21218/CPR.2021.9.3.084
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