A Study on ALD $Al_2O_3$ Films for Rear Surface Passivation of Crystalline Silicon Solar Cells

결정질 태양전지의 후면 패시베이션을 위한 ALD $Al_2O_3$ 막 연구

  • Roh, Si-Cheol (Dept. of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Seo, Hwa-Il (Dept. of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 노시철 (한국기술교육대학교 전기전자통신공학과) ;
  • 서화일 (한국기술교육대학교 전기전자통신공학과)
  • Received : 2011.02.15
  • Accepted : 2011.03.15
  • Published : 2011.03.31

Abstract

To develop high efficiency crystalline solar cells, the rear surface passivation is very important. In this paper, $Al_2O_3$ films deposited by thermal ALD(atomic layer deposition) method were studied for rear surface passivation of crystalline solar cells and their passivation properties were evaluated. After the deposition of $Al_2O_3$ films on p-type Si wafers, the lifetime was increased very much due to the reduction of interface state density and the field effects of the negative fixed charge in the films. Also, optimum annealing condition and effects of SiNx capping layer were investigated. The best lifetime was obtained when the films were annealed at $400^{\circ}C$ for 15min. And the lifetime degradation of the $Al_2O_3$ films with SiNx capping layers was improved compared to those without the capping layers.

Keywords

References

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