COLLABORATIVE RESEARCH: Understanding and harnessing structural defects, doping, passivation, and alloying to increase Voc and efficiency of CdTe solar cells

题目：通过创新工艺设计推进光伏技术非技术描述：该项目旨在开发材料科学和器件工程领域的新知识，以进一步推进基于碲化镉的低成本光伏（PV）技术的性能。尽管在过去的二十年里，光伏技术带来了巨大的市场增长和价格下降，但光伏发电的发电量仍然低于我们总用电量的1%；通过提高器件性能，加速光伏的部署，可以进一步降低成本。该项目将研究几种工艺路线，以提高CdTe电池的输出电压，这是实现接近理想性能的剩余挑战。本研究旨在最大限度地减少晶界和其他结构缺陷的负面影响，以改善控制CdTe电池输出电压的关键材料性能。重点将是研究元素杂质，特别是磷(P)掺杂，及其与CdTe薄膜及其合金中的晶界和其他二维结构缺陷的相互作用。两所学院的研究生将获得薄膜器件制造、晶体生长以及材料和器件表征的先进方法方面的经验。该项目还将影响K-12年级的学生，并提供薄膜太阳能电池的教育资源和光伏教育材料。pi和副研究生将继续对中学生和高中生进行太阳能电池实践教学。技术描述：该项目的主要目标是创造提高CdTe光伏输出电压所需的基础知识和加工技术。本研究的目的如下：(1)研究大mm晶粒尺寸材料中孤立晶界的影响，并利用研究结果来定制多晶薄膜的性能；(2)研究V族掺杂与后沉积工艺对净p型掺杂的综合影响；(3)通过合金化CdTe（Se，S）抑制结构缺陷，增强p型掺杂；(4)在关键器件接口，如主接点和后接点，通过合金化进行下界面复合。上述目标将通过一个整体的方法来实现，包括对大毫米颗粒尺寸的大块材料、器件质量的多晶薄膜和最先进的器件结构的研究。该项目的实验部分将植根于基础材料研究，并扩展到设备工程。这些活动将使用器件物理模型来预测太阳能电池的性能。该项目的结果可能对太阳能电池的制造产生直接影响，并可能在提高效率和降低基于cdte的多晶太阳能电池成本方面产生范式转变影响。

Title: Advancing photovoltaic technologies through innovative process designNon-Technical Description:This project aims at developing new knowledge in the areas of materials science and device engineering to further advance the performance of the low cost photovoltaic (PV) technology based on CdTe. Despite the tremendous market growth and price reduction demonstrated by PV technologies over the last two decades, PV-generated electricity remains below 1% of our total electricity usage; further cost reduction could be achieved through higher device performance leading to accelerated deployment of PV. The project will investigate several processing routes to improve the output voltage of the CdTe cell, which is the remaining challenge to achieving near ideal performance. This research seek to minimize the negative impact of grain boundaries and other structural defects, in order to improve key material properties which control the output voltage of CdTe cells. The focus will be on studying elemental impurities, specifically phosphorous (P) doping, and its interaction with grain boundaries and other 2D structural defects in CdTe films and their alloys. Graduate students at both institutions will gain experience in thin film device fabrication, crystal growth, and advanced methods of characterization of materials and devices. This project will also impact students from K-12 and provide educational resources on thin film solar cells and materials on PV education. The PIs and associate graduate students will continue hands-on solar cell teaching outreach to middle and high school students. Technical Description:The main goal of this project is to create the fundamental knowledge and processing techniques required to advance the output voltage of CdTe PV. This research has the following objectives:(1) investigate the effect of isolated grain boundaries in large mm grain size materials, and use the findings to tailor the properties of polycrystalline thin films; (2) investigate the combined effect of group V dopant(s) with post-deposition processing techniques on the net p-type doping; (3) enhance p-type doping by suppressing structural defects through alloying CdTe(Se,S); (4) lower interface recombination at critical device interfaces, such as the main junction and back contact, through alloying. The above goals will be pursued through a holistic approach that will include the investigation of large mm grain size bulk materials, device quality polycrystalline thin films, and state-of-the-art device structures. The experimental component of the project will be rooted in fundamental material studies and expanded to device engineering. The activities will be guided using device physics models to predict solar cell performance. Results from this project may have a direct impact on solar cell manufacturing and could lead to a paradigm shift impact in terms of improving efficiency and decreasing cost of polycrystalline CdTe-based solar cells.