双光栅结构薄膜太阳能电池的优化

Optimization of thin film solar cells with double-grating structure

为了提高单晶硅薄膜太阳能电池短路电流密度和转换效率,采用在单晶硅薄膜太阳能电池正背面分别集成硅介质光栅和铝金属光栅的方法,并利用有限时域差分法软件仿真研究了两种光栅的周期、厚度、占空比对单晶硅薄膜太阳能电池短路电流密度和光转换效率的影响.结果表明,通过优化可得当正背面光栅都处于最优值时(介质光栅占空比F=0.8、介质光栅周期P=0.632μm、介质光栅厚度hg=0.42μm;金属光栅占空比F1=0.9、金属光栅周期P=0.632μm、金属光栅厚度hm=0.005μm),短路电流密度可达35.15mA/cm2,转换效率为43.35%;将最优光栅单晶硅薄膜太阳能电池与传统单晶硅薄膜太阳能电池对比,无论是光程路径还是吸收效率,光栅单晶硅薄膜太阳能电池都有显著的提高.这为以后制备高性能薄膜太阳能电池提供了理论指导.

In order to improve the short circuit current density and conversion efficiency of crystalline silicon thin film solar cells, a silicon dielectric grating and an aluminium metal grating were integrated on the front and back of single crystal silicon thin film solar cells respectively. The effect of the period, thickness and duty cycle of both the gratings on the short-circuit current density and optical conversion efficiency of single crystal silicon thin film solar cells were simulated with finite difference time-domain software. The results show that, the short-circuit current density can reach 35. 15mA/cm^2 and the conversion efficiency is 43. 35% when both the front and back gratings are at the optimum value (for the dielectric grating, duty cycle F=0. 8 , period P = 0. 632μm, thickness hg = 0. 42μm;for the metal grating, duty cycle F1 =0.9, period P = 0. 632μm and thickness hm - 0. 005 μm). After comparing the optimal grating monocrystalline silicon thin film solar cells with traditional monocrystalline silicon thin film solar cells, the grating monocrystalline silicon thin film solar cells have a significant improvement in both optical path and absorption efficiency. This study provides theoretical guidance for the preparation of high performance thin film solar cells in the future.