银纳米颗粒减反射特性的理论研究

Theoretical investigation of anti-reflection properties of Ag-nanoparticles

为增强晶体硅太阳电池的光利用效率,提高光电转换效率,研究了金属银纳米颗粒的光学散射性质.基于银纳米粒子表面等离子激元效应和MIE散射理论,采用Matlab数值计算,理论分析了不同银纳米颗粒尺寸和银粒子分布密度对太阳光谱各波长的散射特性.获得了实现高的光透过率所需最佳银纳米颗粒半径范围,研究发现随着银纳米颗粒半径增加,偶极峰红移、高极峰逐渐出现.定量地给出了最佳颗粒分布密度随银粒子半径的变化规律,建立了计算减反射膜透射率的理论方法,找到了银纳米颗粒光学透过率的简单函数表达式,能为实验研究提供理论指导.

In order to trap more sunlight onto the crystalline silicon solar cell and improve the photo-electric conversion efficiency,it is very important to study the optical scattering properties of silver nanoparticles on silicon wafer. Based on localized surface plasmon effect and MIE scattering theory, using numerical calculation by Matlab, the scattering properties of solar spetra for different radius and density of silver nanoparticle are investigated in theory. The dependence of the optimal optical transmittance on the radius and density of Ag nanoparticle is obtained. Furthermore,it is found that the dipole peaks is redshifted and high mode peaks gradually emerges. Firstly this paper gives the variation of the best Ag nanoparticle density with the radius quantitively,the theoretical method calculating the transmittance of the nanoparticle antireflection film is also established. As a result,the simple functional expression of transmittance is deduced in this work,which provides a theoretical guidance for experimental research.