基于硅倒金字塔微观特征调控的高广角发电量薄硅HIT太阳电池性能研究

硅片厚度减小带来太阳电池降本和应用拓展的同时也增加了其对表面陷光及钝化的要求。近期研究发现陷光结构微观特征改变有益于电池广角陷光及其表面钝化改善，从而提升其广角发电量并进一步降本。本项目基于提升薄硅HIT电池广角发电量的目的，以硅倒金字塔为研究对象，开展基于结构微观特征调控的电池性能研究：（1）采用铜镍双金属辅助化学腐蚀法结合后处理可控制备倒金字塔结构，分析化学反应动力学和结构形成过程，阐明其内部形成原理；（2）利用实验与数值模拟相结合的方法详细考察结构尺寸、底部夹角等倒金字塔微观特征与硅在不同光入射角下光吸收的内在联系，探讨结构特征对电场能量分布和广角陷光作用机制；（3）在此基础上，研究倒金字塔微观特征与表面钝化依赖关系，揭示其对钝化效果影响机理，发展倒金字塔表面缺陷控制新方法。通过深入剖析结构微观特征与薄硅HIT电池广角发电量之间的内在关联性，为高发电量薄硅电池研究提供理论和实验基础。

The reduction in the thickness of c-Si wafers brings about cost reduction and application expansion of solar cells, but also increases its requirements for surface light trapping and passivation. Recent studies have found that the change in the microscopic characteristics of the light trapping structure is beneficial to the improvement of the wide-angle light trapping and surface passivation of the cell, thereby increasing its wide-angle power generation and further reducing costs. With the purpose of increasing the wide-angle power generation of thin silicon HIT cells, this project takes the silicon inverted pyramid as the research object to carry out cell performance research by adjusting structural microscopic characteristics: (1) The use of copper-nickel co-assisted chemical etching method combined with post-processing technology can control the inverted pyramid structure, analyze the chemical reaction kinetics and the structure formation process, and clarify its underlying formation mechanism; (2) Use a combination of experiment and numerical simulation to investigate the relationship in detail between the microscopic characteristics of the inverted pyramid such as the structure size and the bottom angle and so on and the light incident angle, and explore the mechanism of structural characteristics related electric field energy distribution and wide-angle light trapping; (3) On this basis, study the dependence of the microscopic characteristics of the inverted pyramid on the surface passivation, reveal the mechanism of its influence on the passivation effect, and develop a new method for controlling the surface defects of the inverted pyramid. Through the in-depth analysis of the underlying correlation between the microstructure and the wide-angle power generation of thin silicon HIT cells, it provides a theoretical and experimental basis for the research of high power generation thin silicon cells.