晶硅异质结太阳电池表面的减反层是ITO薄膜,其低的紫外透过率、高的近红外光学损耗限制了电池效率的提升。为此,本文设计了三层减反膜来减小ITO薄膜的光学损耗。利用光学薄膜膜系设计软件TFCalc、光线追迹程序(OPAL 2)和太阳电池模拟软件 PC1D 对三层减反膜的光学性能和相应电池的电学性能进行了模拟和分析,并对折射率色散效应、晶硅表面形貌以及各膜层的厚度容差进行了讨论。结果表明:考虑折射率色散效应的三层减反膜比ITO薄膜的寄生吸收更小,减反射带宽更大;绒面硅表面减反膜比平面硅表面减反膜的加权平均光学损耗降低了2.43个百分点,相应电池的短路电流密度和转换效率分别提高了0.82 mA/cm 2和0.34个百分点;减反膜中低折射率的SiOx 膜层具有更大的厚度容差范围。

ITO film, as typical antireflection film in crystalline silicon heterogeneous solar cells, has low UV transmittance and high near-infrared optical loss, which restricts the efficiency improvement of the solar cells. Therefore, triple-layer antireflection film was designed in this paper. Firstly, we simulated and analyzed the optical performance of the triple-layer antireflection film and the electrical characteristics of the corresponding solar cell by using optical film design software TFCalc, light ray tracing program (OPAL 2), and solar cell simulation software PC1D. Then, the refractive-index dispersion effect, the surface morphology of crystalline silicon substrate, and the thickness tolerance of the films were discussed. The results show that the triple-layer antireflection film considering the refractive-index dispersion effect presented smaller parasitic absorption and larger antireflection bandwidth than ITO film. Besides, the weighted average optical loss of the triple-layer antireflection film on textured silicon was 2.43 percentage points lower than that on planar silicon, and the short-circuit current density and conversion efficiency of the corresponding solar cells were increased by 0.82 mA/cm ² and 0.34 percentage points, respectively. In addition, the SiO_x films with low refractive index had a larger thickness tolerance range.