Reuna Jarno, Hietalahti Arttu, Aho Arto, Isoaho Riku, Aho Timo, Vuorinen Marianna, Tukiainen Antti, Anttola Elina, Guina Mircea
Optoelectronics Research Centre, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland.
ACS Appl Energy Mater. 2022 May 23;5(5):5804-5810. doi: 10.1021/acsaem.2c00133. Epub 2022 Apr 25.
The optical performance of a multilayer antireflective coating incorporating lithography-free nanostructured alumina is assessed. To this end, the performance of single-junction GaInP solar cells and four-junction GaInP/GaAs/GaInNAsSb/GaInNAsSb multijunction solar cells incorporating the nanostructured alumina is compared against the performance of similar solar cells using conventional double-layer antireflective coating. External quantum efficiency measurements for GaInP solar cells with the nanostructured coating demonstrate angle-independent operation, showing only a marginal difference at 60° incident angle. The average reflectance of the nanostructured antireflective coating is ∼3 percentage points smaller than the reflectance of the double-layer antireflective coating within the operation bandwidth of the GaInP solar cell (280-710 nm), which is equivalent of ∼0.2 mA/cm higher current density at AM1.5D (1000 W/m). When used in conjunction with the four-junction solar cell, the nanostructured coating provides ∼0.8 percentage points lower average reflectance over the operation bandwidth from 280 to 1380 nm. However, it is noted that only the reflectance of the bottom GaInNAsSb junction is improved in comparison to the planar coating. In this respect, since in such solar cells the bottom junction typically is limiting the operation, the nanostructured coating would enable increasing the current density ∼0.6 mA/cm in comparison to the standard two-layer coating. The light-biased current-voltage measurements show that the fabrication process for the nanostructured coating does not induce notable recombination or loss mechanisms compared to the established deposition methods. Angle-dependent external quantum efficiency measurements incline that the nanostructured coating excels in oblique angles, and due to low reflectance at a 1000-1800 nm wavelength range, it is very promising for next-generation broadband multijunction solar cells with four or more junctions.
评估了一种包含无光刻纳米结构氧化铝的多层抗反射涂层的光学性能。为此，将包含纳米结构氧化铝的单结GaInP太阳能电池和四结GaInP/GaAs/GaInNAsSb/GaInNAsSb多结太阳能电池的性能与使用传统双层抗反射涂层的类似太阳能电池的性能进行了比较。具有纳米结构涂层的GaInP太阳能电池的外部量子效率测量表明其具有与角度无关的运行特性，在60°入射角时仅显示出微小差异。在GaInP太阳能电池的工作带宽（280 - 710 nm）内，纳米结构抗反射涂层的平均反射率比双层抗反射涂层的反射率小约3个百分点，这相当于在AM1.5D（1000 W/m）下电流密度高约0.2 mA/cm²。当与四结太阳能电池结合使用时，纳米结构涂层在280至1380 nm的工作带宽上提供的平均反射率低约0.8个百分点。然而，需要注意的是，与平面涂层相比，只有底部GaInNAsSb结的反射率得到了改善。在这方面，由于在这种太阳能电池中底部结通常限制了运行，与标准双层涂层相比，纳米结构涂层将使电流密度增加约0.6 mA/cm²。光偏置电流 - 电压测量表明，与既定的沉积方法相比，纳米结构涂层的制造过程不会引发明显的复合或损耗机制。与角度相关的外部量子效率测量表明，纳米结构涂层在斜角方面表现出色，并且由于在1000 - 1800 nm波长范围内的低反射率，它对于具有四个或更多结的下一代宽带多结太阳能电池非常有前景。
