Efficiency improvement of buried contact solar cells using MgF/sub 2//CeO/sub 2/ double layer antireflection coatings

This paper describes an efficiency improvement of buried contact solar cell (BCSC) with a structure of MgF/sub 2//CeO/sub 2//Ag/Cu/Ni grid/n/sup +/ emitter/p-type Si base/P/sup +//Al. Theoretical and experimental investigations were performed on a double layer antireflection (DLAR) coating of MgF/sub 2//CeO/sub 2/. The authors investigated CeO/sub 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. An optimized DLAR coating showed a reflectance as low as 2.04% in the wavelengths ranged from 0.4 /spl mu/m to 1.1 /spl mu/m. BCSC cell efficiency was improved from 16.2% without any AR coating to 19.9% by employing DLAR coatings. Further details on MgF/sub 2//CeO/sub 2/ DLAR coatings on the BCSC cells are presented in this paper.