Hung Mu-Min, Han Hau-Vei, Hong Chung-Yu, Hong Kuo-Hsuan, Yang Tung-Ting, Yu Peichen, Wu Yu-Rue, Yeh Hong-Yih, Huang Hong-Cheng
Opt Express. 2014 Mar 10;22(5):A295-300.
Biomimetic nanostructures have shown to enhance the optical absorption of Ga(0.5)In(0.5)P/GaAs/Ge triple junction solar cells due to excellent antireflective (AR) properties that, however, are highly dependent on their geometric dimensions. In practice, it is challenging to control fabrication conditions which produce nanostructures in ideal periodic arrangements and with tapered side-wall profiles, leading to sacrificed AR properties and solar cell performance. In this work, we introduce compound biomimetic nanostructures created by depositing a layer of silicon dioxide (SiO(2)) on top of titanium dioxide (TiO(2)) nanostructures for triple junction solar cells. The device exhibits photogenerated current and power conversion efficiency that are enhanced by ~8.9% and ~6.4%, respectively, after deposition due to their improved antireflection characteristics. We further investigate and verify the optical properties of compound structures via a rigorous coupled wave analysis model. The additional SiO(2) layer not only improves the geometric profile, but also serves as a double-layer dielectric coating. It is concluded that the compound biomimetic nanostructures exhibit superior AR properties that are relatively insensitive to fabrication constraints. Therefore, the compound approach can be widely adopted for versatile optoelectronic devices and applications.
仿生纳米结构已被证明可增强Ga(0.5)In(0.5)P/GaAs/Ge三结太阳能电池的光吸收，这归因于其优异的抗反射（AR）特性，然而，这些特性高度依赖于它们的几何尺寸。在实际应用中，控制制造条件以产生具有理想周期性排列和锥形侧壁轮廓的纳米结构具有挑战性，这会导致抗反射性能和太阳能电池性能的牺牲。在这项工作中，我们介绍了通过在三结太阳能电池的二氧化钛（TiO(2)）纳米结构顶部沉积一层二氧化硅（SiO(2)）而创建的复合仿生纳米结构。由于其改进的抗反射特性，该器件在沉积后分别表现出约8.9%和约6.4%的光生电流和功率转换效率提高。我们通过严格耦合波分析模型进一步研究和验证了复合结构的光学特性。额外的SiO(2)层不仅改善了几何轮廓，还充当双层介电涂层。得出的结论是，复合仿生纳米结构表现出对制造限制相对不敏感的优异抗反射特性。因此，这种复合方法可广泛应用于各种光电器件和应用。
