非晶硅太阳能电池的光学分析

Optical Analysis of Amorphous Silicon Solar Cell

我们采用一种新方法——光学导纳分析,把非晶硅太阳能电池看作由吸收膜和透明膜组成的多层膜系,计算了该膜系的光学导纳,分析了电池的光学性质。 电池吸收谱中存在干涉峰。通过考察各层膜光学参数对光吸收的影响,发现(ⅰ)高反射背接触的电池结构可增加0.6—0.7μm的吸收,(ⅱ)非晶硅膜厚能改变干涉峰在光谱中的位置;(ⅲ)减反膜(AR)与短波区的反射率密切相关,选择最佳AR膜厚能够减少反射损失;并且AR最佳膜厚几乎与非晶硅膜厚无关。

In this paper a new method-optical admittance analysis is adopted. Considering anamorphous silicon solar cell as a mutilayer system comoosed of absorbing and non-absorbingmaterials,we work out the optical admittance of the cell and analyse the optical process in thecell.There are interference peaks in the absorption spectrum of the cell. By analysis of eachlayer, we find that (i) highly reflecting back contacts can increase the absorption in the regionof 0.6-0.7μm; (ii) the variation in the thickness of a-Si:H can cause the frequency shift of thepeak; (iii) antireflection (AR) film can greatly change the reflectivity in the short wavelengh(?)egion, and the effect of AR is little dependent on the thickness of a-Si:H.