Morawiec Seweryn, Mendes Manuel J, Filonovich Sergej A, Mateus Tiago, Mirabella Salvatore, Aguas Hugo, Ferreira Isabel, Simone Francesca, Fortunato Elvira, Martins Rodrigo, Priolo Francesco, Crupi Isodiana
Opt Express. 2014 Jun 30;22 Suppl 4:A1059-70. doi: 10.1364/OE.22.0A1059.
Plasmonic light trapping in thin film silicon solar cells is a promising route to achieve high efficiency with reduced volumes of semiconductor material. In this paper, we study the enhancement in the opto-electronic performance of thin a-Si:H solar cells due to the light scattering effects of plasmonic back reflectors (PBRs), composed of self-assembled silver nanoparticles (NPs), incorporated on the cells' rear contact. The optical properties of the PBRs are investigated according to the morphology of the NPs, which can be tuned by the fabrication parameters. By analyzing sets of solar cells built on distinct PBRs we show that the photocurrent enhancement achieved in the a-Si:H light trapping window (600 - 800 nm) stays in linear relation with the PBRs diffuse reflection. The best-performing PBRs allow a pronounced broadband photocurrent enhancement in the cells which is attributed not only to the plasmon-assisted light scattering from the NPs but also to the front surface texture originated from the conformal growth of the cell material over the particles. As a result, remarkably high values of J(sc) and V(oc) are achieved in comparison to those previously reported in the literature for the same type of devices.
在薄膜硅太阳能电池中，等离子体光捕获是一种通过减少半导体材料用量来实现高效率的有前途的途径。在本文中，我们研究了由自组装银纳米颗粒（NPs）组成的等离子体背反射器（PBRs）的光散射效应，对非晶硅氢化（a-Si:H）薄膜太阳能电池光电性能的增强作用，该反射器集成在电池的背面接触层上。根据纳米颗粒的形态研究了PBRs的光学性质，其形态可通过制造参数进行调整。通过分析基于不同PBRs构建的多组太阳能电池，我们发现，在a-Si:H光捕获窗口（600 - 800 nm）内实现的光电流增强与PBRs的漫反射呈线性关系。性能最佳的PBRs能使电池中的光电流显著增强，这不仅归因于纳米颗粒的等离子体辅助光散射，还归因于电池材料在颗粒上的共形生长所产生的前表面纹理。结果，与文献中先前报道的同类器件相比，实现了显著更高的短路电流密度（J(sc)）和开路电压（V(oc)）值。
