A Study on MgF$_2$/CeO$_2$ AR Coating of Mono-Crystalline Silicon Solar Cell

단결정 실리콘 태양전지의 MgF$_2$/CeO$_2$ 반사 방지막에 환한 연구

  • 유진수 (성균관대학 정보통신공학부) ;
  • 이재형 (군산대학 전자정보공학부) ;
  • 이준신 (성균관대학 정보통신공학부)
  • Published : 2003.10.01

Abstract

This paper presents a process optimization of antireflection (AR) coating on crystalline Si solar cells. Theoretical and experimental investigations were performed on a double-layer AR (DLAR) coating of MgF$_2$/CeO$_2$. We investigated CeO$_2$ films as an AR layer because they have a proper refractive index of 2.46 and demonstrate the same lattice constant as Si substrate. RF sputter grown CeO$_2$ film showed strong dependence on a deposition temperature. The CeO$_2$ deposited at 40$0^{\circ}C$ exhibited a strong (111) preferred orientation and the lowest surface roughness of 6.87 $\AA$. Refractive index of MgF$_2$ film was measured as 1.386 for the most of growth temperature. An optimized DLAR coating showed a reflectance as low as 2.04% in the wavelengths ranged from 0.4${\mu}{\textrm}{m}$ to 1.1${\mu}{\textrm}{m}$. We achieved the efficiencies of solar cells greater than 15% with 3.12% improvement with DLAR coatings. Further details on MgF$_2$, CeO$_2$ films, and cell fabrication parameters are presented in this paper.

Keywords

Cz Si wafer;AR coating;MgF$_2$;CeO$_2$;Fire-through;Texturing;Refractive index;Reflectance

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