Current Photovoltaic Research

Korea Photovoltaic Society (한국태양광발전학회)
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Stability Improvement of CdTe Solar Cells using ZnTe:Na Back Contact

Na 도핑된 ZnTe 후면전극을 이용한 CdTe 태양전지의 안정성 개선에 관한 연구

  • Cha, Eun Seok (Department of Materials Science and Engineering, KAIST) ;
  • Park, Kyu Charn (Department of Materials Science and Engineering, KAIST) ;
  • Ahn, Byung Tae (Department of Materials Science and Engineering, KAIST)
  • 차은석 (한국과학기술원 신소재공학과) ;
  • 박규찬 (한국과학기술원 신소재공학과) ;
  • 안병태 (한국과학기술원 신소재공학과)
  • Received : 2015.02.22
  • Accepted : 2015.03.03
  • Published : 2015.03.31
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Abstract

Cu doping by copper or $Cu_2Te$ materials enhances p+ formation in CdTe near the back contact interface, allowing better formation of ohmic contact. However, the Cu in CdTe junction is also considered as a principal component of CdTe cell degradation. In this paper, Na-doped ZnTe layer was employed as a back contact material to improve the stability of CdTe solar cells. As a process variable, post $CdCl_2$ treatment of CdS/CdTe film was conducted before or after depositing ZnTe:Na on CdTe. The change of the photovoltaic properties of CdTe cells were investigated with aging time. Low-temperature photoluminescence analysis was conducted to describe the degradation mechanism. The result showed that the CdTe solar cells with better stability compare to Cu contact were achieved using an optimized ZnTe:Na back contact.

Keywords

References

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