硅基薄膜太阳电池一维光子晶体背反射器的模拟设计与制备  

Simulation, design and fabrication of one-dimensional photonic crystal back reflector for silicon thin film solar cell

作　　者：陈培专[1] 侯国付[1] 索松 倪牮[1] 张建军[1] 张晓丹[1] 赵颖[1] 

机构地区：[1]南开大学光电子薄膜器件与技术研究所,光电子薄膜器件与技术天津市重点实验室,光电信息技术科学教育部重点实验室,天津300071

出　　处：《物理学报》2014年第12期447-455,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61176060;61377031);天津市自然科学基金重点项目(批准号:12JCZDJC28300);国家高技术研究发展规划(批准号:2011AA050503);国家重点基础研究发展计划(批准号:2011CBA00705;2011CBA00706;2011CBA00707);天津市重大科技支撑计划(批准号:11TXSYGX22100)资助的课题~~

摘　　要：从模拟和实验两个方面研究了一种适用于硅基薄膜太阳电池的一维光子晶体新型背反射器.首先采用时域有限差分方法,模拟研究了组成一维光子晶体的两种介质的折射率比、厚度比以及周期厚度对光子禁带的影响.基于模拟结果,制备出一种由低折射率SiOx层与高折射率非晶硅a-Si层周期性交叠构成的禁带可调式一维光子晶体背反射器.通过改变a-Si层的厚度,使得禁带范围由500—750 nm波长范围红移至650—1100 nm,反射率分别达到96.4%和99%.将上述结构的一维光子晶体作为背反射器分别应用于非晶硅单结太阳电池和非晶硅/微晶硅双结叠层太阳电池,与没有背反射结构电池相比,短路电流密度分别提升了18.3%和15.2%.同时模拟研究了在不同入射角度下自然光、TE波和TM波对光子晶体反射特性的影响.研究结果表明,在太阳电池中,光线倾斜入射对一维光子晶体反射率的影响有限.A new type of high-performance back reflector based on one-dimensional photonic crystal （1D PC） is introduced in this paper. The 1D PC is designed by alternately depositing a-Si and a-SiOx layers. Firstly the influences of refractive index, layer-thickness and corresponding periodicity on the band-gap of 1D PC are simulated using the finite difference time domain method. Based on the simulation results 1D PCs with different bandgaps are experimentally deposited. Just by adjusting the a-Si layer thickness, the high-reflection bandgaps in ranges of 500-750 nm and 650-1100 nm are easily achieved. The reflectivity values of 96.4% and 99% in the above-mentioned bandgaps are obtained. Comparing with the cells without a back reflector, a relative enhancement of 18.3%and 15.2%can be achieved for the short circuit current densities of a-Si：H single-junction and a-Si：H/μc-Si：H tandem solar cells, respectively, by integrating the above optimized 1D PC in the back. Also the influences of incident angles of white light, TE waves and TM waves on the reflectivity of 1D PC are studied using a software to generate spectrophotometric and ellipsometric spectra of a thin film stack. It is found that the reflectivity of 1D PC in solar cell is less affected by the changes of incident angles from air.

关 键 词：硅基薄膜太阳电池 一维光子晶体 禁带可调 背反射 

分 类 号：TM914.4[电气工程—电力电子与电力传动]