薄膜太阳能电池双界面光栅结构的优化分析  

Optimization Analysis of Dual-Interface Grating Structures for Thin Film Solar Cells

作　　者：陈科[1] 吴胜 郑红梅[1] 田文立 刘志杰 Chen Ke;Wu Sheng;Zheng Hongmei;Tian Wenli;Liu Zhijie(College of Mechanical Engineering,Hefei University of Technology,Hefei,Anhui 230009,China)

机构地区：[1]合肥工业大学机械工程学院,安徽合肥230009

出　　处：《激光与光电子学进展》2022年第7期372-378,共7页Laser & Optoelectronics Progress

基　　金：国家自然科学基金重点项目(51435003)。

摘　　要：设计了一种半圆形前置与梯形后置双界面的光栅结构的单晶硅薄膜太阳能电池,利用时域有限差分法对该结构和对照组进行了模拟计算,通过分析短路电流密度和吸收光谱可知,双界面光栅结构的光捕获性能优于单界面光栅结构,利用电磁场分布对该结构在长波段(750~1100 nm)的吸收增强机理进行了分析。此外,针对前置半圆形后置梯形光栅结构,进一步优化了后置梯形光栅的左右斜率与同周期下前后光栅的偏移程度,结果表明非规则的梯形结构具有较好的光捕获表现,通过吸收效率云图也能发现偏移程度在40 nm时效果最佳。通过计算分析,短路电流密度的最优值达到了20.17 mA/cm^(2),相较于平板结构的短路电流密度提高了58.1%,研究结果对于薄膜太阳能电池的光栅结构设计具有一定的指导意义。A structure of the front semicircle and rear trapezoidal dual-interface grating monocrystalline silicon thin film solar cell was designed.The structure and the control group were simulated by the finite-difference time-domain method.It is shown that the dual-interface has better light-trapping performance than the single-interface grating structure by analysis of the short circuit current density and absorption spectrum.The absorption enhancement mechanism of the structure at long wavelength(750-1100 nm) was analyzed by using electromagnetic field distribution.In addition,for the front semicircle rear trapezoidal grating structure,the left and right slope of rear trapezoidal grating and the offset degree of front and rear gratings under the same period are further optimized.The results show that the irregular trapezoidal gratings have better light-trapping performance,and through the absorption efficiency cloud diagram,the best effect can be found when the offset degree is at 40 nm.The optimal short-circuit current density reaches 20.17 mA/cm~2,which is 58.1% higher than the planar structure by calculation and analysis.The research results have certain guiding significance for the grating structure design of thin film solar cells.

关 键 词：薄膜 太阳能电池 时域有限差分法 光捕获 半圆形光栅 梯形光栅 短路电流密度 

分 类 号：TK514[动力工程及工程热物理—热能工程]