[ $a-Si:H/{\mu}c-Si:H$ ] thin-film tandem solar cells

비정질/마이크로 탠덤 구조형 실리콘 박막 태양전지

  • 이정철 (한국에너지기술연구원 태양광발전연구단) ;
  • 송진수 (한국에너지기술연구원 태양광발전연구단) ;
  • 윤경훈 (한국에너지기술연구원 태양광발전연구단)
  • Published : 2006.06.22

Abstract

This paper briefly introduces silicon based thin film solar cells: amorphous (a-Si:H), microcrystalline ${\mu}c-Si:H$ single junction and $a-Si:H/{\mu}c-Si:H$ tandem solar cells. The major difference of a-Si:H and ${\mu}c-Si:H$ cells comes from electro-optical properties of intrinsic Si-films (active layer) that absorb incident photon and generate electron-hole pairs. The a-Si:H film has energy band-gap (Eg) of 1.7-1.8eV and solar cells incorporating this wide Eg a-Si:H material as active layer commonly give high voltage and low current, when illuminated, compared to ${\mu}c-Si:H$ solar cells that employ low Eg (1.1eV) material. This Eg difference of two materials make possible tandem configuration in order to effectively use incident photon energy. The $a-Si:H/{\mu}c-Si:H$ tandem solar cells, therefore, have a great potential for low cost photovoltaic device by its various advantages such as low material cost by thin-film structure on low cost substrate instead of expensive c-Si wafer and high conversion efficiency by tandem structure. In this paper, the structure, process and operation properties of Si-based thin-film solar cells are discussed.

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