Wavelength and angle resolved reflectance measurements of pyramidal textures for crystalline silicon photovoltaics
Wavelength and angle resolved reflectance measurements of pyramidal textures for crystalline silicon photovoltaics
复制标题
DOI：
10.1002/pip.3319
复制
发表时间：
2020-07-09
影响因子：
6.7
通讯作者：
Boden, Stuart A.
中科院分区：
文献类型：
--
作者：
Scheul, Tudor E.;Khorani, Edris;Boden, Stuart A.
波长和角度分辨散射（WARS）反射率测量作为表征纹理化前表面的光捕获特性的手段对光伏（PV）工业具有吸引力。此外，在PV模块级，其中存在包括增透剂和玻璃的堆叠，大角度散射可以促进界面处的全内反射，并将光重定向回太阳能电池，从而增加器件的光电流。在这项工作中，我们提出了一个氢氧化钾（KOH）蚀刻的随机金字塔表面在6度-90度范围内的WARS测量，并确定光子通过反射从金字塔的各个方面的经验的主要路径。我们的研究结果，结合光线跟踪预测，表明重新评估的形态模拟输入的建议，更全面的描述实验光路，由于功率分布在多个散射角和较低的平均金字塔底角。此外，我们讨论了在玻璃-空气界面处捕获的光的总量的影响，并表明，对于一个典型的密封剂的折射率为1.5，大约14.5%的散射光被预测被捕获的制造金字塔纹理。这比假设二面角底角固定为54.74度时计算出的3.8%的捕获率显著增加。
Wavelength and angle resolved scattering (WARS) reflectance measurements are attractive to the photovoltaic (PV) industry as a means of characterizing the light-trapping properties of a textured front surface. Moreover, at the PV module level, where a stack comprising encapsulants and glass is present, large angle scattering can promote total internal reflection at the interfaces and redirect light back towards the solar cell, thus increasing the photocurrent of the device. In this work, we present WARS measurements of a potassium hydroxide (KOH)etched random pyramid surface in the 6 degrees-90 degrees range and identify the main paths the photons experience through reflections from various facets of the pyramids. Our results, combined with ray-tracing predictions, show that a reassessment of the morphology for simulation inputs is advised for a more comprehensive description of the experimental light paths due to a distribution of power across multiple scattering angles and a lower average pyramid base angle. In addition, we discuss the implications on the total amount of light trapped at the glass-air interface and show that for a typical encapsulant refractive index of 1.5, approximately 14.5% of the scattered light is predicted to be trapped by the fabricated pyramidal texture. This is a significant increase over the 3.8% calculated to be trapped when assuming a dihedral base angle fixed to 54.74 degrees.