GOALI: Polarized Infrared Imaging for the Mechanics of Photovoltaic Wafers

这项学术与工业联络资助机会（GOALI）奖的研究目标是利用红外光弹性和偏振光致发光检测技术的结合，研究薄硅光伏晶圆的应力、缺陷和失效机制。硅晶片是太阳能电池中最常见的基础材料，但由于晶体生长过程中产生的应力和缺陷，制造过程中的材料损失仍然是一个重大问题。在该奖项的支持下，将使用锁定红外光弹性直接研究光伏晶圆中的应力与缺陷之间的关系。此外，一种基于锁定偏振光致发光方法的新型检测技术将被开发出来，并用于研究应力和缺陷与材料吸收或发射的光的相互作用。最后，这些材料的应力和破坏之间的关系将通过一系列的成像和断裂实验来研究。该奖项将支持大学和行业研究人员之间的合作努力。该研究将对太阳能行业产生重大影响，因为它将有助于解释应力和缺陷在光伏晶圆失效中的作用，并为基于机械故障概率的硅光伏晶圆快速检测和分选提供途径。这些结果也将增加对晶体材料中光与缺陷相互作用的基本理解。除了研究目标之外，该奖项还将支持研究生和本科生的教育和培训。学术/行业合作伙伴关系将通过每年夏季安排一名研究生研究助理在行业设施中学习表征和制造方法来突出。本科生将参与伊利诺伊大学的工程推广活动，并在主要研究者的实验室进行研究。

The research objective of this Grant Opportunity for Academic Liaison with Industry (GOALI) award is to investigate the mechanics of stress, defects, and failure in thin silicon photovoltaic wafers using a combination of infrared photoelasticity and polarized photoluminescence inspection techniques. Silicon wafers are the most common base material in solar cells, but due to stress and defects that arise during the crystal growth process, material losses during manufacturing remain a significant problem. Under support from this award, the relationship between stress and defects in photovoltaic wafers will be studied directly using lock-in infrared photoelasticity. Also, a new class of inspection techniques based on a lock-in polarized photoluminescence method, in which both intensity and polarization of emitted light is measured, will be developed and used to study the interaction of stress and defects with light absorbed or emitted by the material. Finally, the relationship between stress and failure in these materials will be investigated using a series of imaging and fracture experiments.The award will support a collaborative effort between university and industry researchers. The research could have significant impact in the solar energy industry, as it will help to explain the role of stress and defects in photovoltaic wafer failure, and could enable a pathway to rapid inspection and sorting of silicon photovoltaic wafers based on the probability of mechanical failure. The results will also add to the fundamental understanding of the interaction of light with defects in crystalline materials. In addition to the research objectives, the award will support graduate and undergraduate education and training. The academic/industry partnership will be highlighted by the annual summer placement of a graduate research assistant in the industry facility to learn characterization and manufacturing methods. Undergraduate students will be involved through an engineering outreach event at the University of Illinois, and through research in the laboratory of the Principle Investigator.