Acta Optica Sinica, Vol. 40, Issue 24, 2431001 (2020)

Design and Analysis of Triple-Layer Antireflection Film for Crystalline Silicon Heterogeneous Solar Cell

Abstract

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.

keywords

• crystalline silicon heterogeneous solar cell
• ITO
• optical loss
• thin films
• triple-layer antireflection film
• weighted average reflectivity