Authors: Jing Rao Sergey Varlamov Jongsung Park Svetlana Dligatch Anatoli Chtanov
Publish Date: 2012/12/21
Volume: 8, Issue: 2, Pages: 785-791
Abstract
Surface plasmonicenhanced light trapping from metal nanoparticles is a promising way of increasing the light absorption in the active silicon layer and therefore the photocurrent of the silicon solar cells In this paper we applied silver nanoparticles on the rear side of polycrystalline silicon thin film solar cell and systematically studied the dielectric environment effect on the absorption and shortcircuit current density Jsc of the device Three different dielectric layers magnesium fluoride MgF2 n = 14 tantalum pentoxide Ta2O5 n = 22 and titanium dioxide TiO2 n = 26 were investigated Experimentally we found that higher refractive index dielectric coatings results in a redshift of the main plasmonic extinction peak and higher modes were excited within the spectral region that is of interest in our thin film solar cell application The optical characterization shows that nanoparticles coated with highest refractive index dielectric TiO2 provides highest absorption enhancement 756 however from the external quantum efficiency characterization highest shortcircuit current density Jsc enhancement of 458 was achieved by coating the nanoparticles with lower refractive index MgF2 We also further optimize the thickness of MgF2 and a final 502 Jsc enhancement was achieved with a 210nm MgF2 coating and a back reflector
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