Materials World Network: Correlation of the Structural and Optoelectronic Properties of Grain Boundaries in Polar Covalent Semiconductors

这个材料世界网络项目是伊利诺伊大学厄巴纳-香槟分校和德国哈恩-迈特纳研究所的科学家和学生之间的联合研究和教育活动，旨在研究基本问题-一类称为极性共价半导体的材料中晶体之间的边界如何影响其光学和电子特性。 极性共价半导体，如铜铟硒[CuInSe 2]和相关材料，在大面积器件中具有最大的最终能量转换效率潜力。 这项研究计划解决了这些材料目前面临的主要基础科学问题-晶体之间的边界如何影响器件的性能。该奖项的主要目标是生长大而薄的CuInSe 2单晶，这些单晶连接在可以详细研究和建模的明确晶界中。先进的纳米级分辨率的光学探针方法将被用来检查光与材料相互作用的方式以及晶界如何影响行为。 其结果将是一个全面的了解晶界极性共价半导体从氮化铝到硒化锌一般。所应用的晶体生长技术和所研究的一般科学问题将对太阳能电池中使用的一类材料产生强烈的影响，它们已被确定为最有前途的大规模发电的可再生能源技术。 该计划汇集了德国和伊利诺伊大学领先的基础科学研究小组，并将扩大正在进行的研究活动，大大增加研究生和本科生的交流。 该项目可以增强对极性共价半导体核心特性之一的理解，即它们在存在结构缺陷的情况下发挥作用的能力。这些结果对其他半导体的晶界钝化以及光电子器件、光发射器和光传感器等光学器件的改进具有潜在的意义。国际交流将加强包括美国和德国学生在内的研究人员之间的培训和思想交流。国际合作的附加价值在于交流研究技术，并对美国研究生和本科生进行德国集团擅长的技术培训。 拟议的本科生和研究生与K-12学生的互动，包括课堂参观，远程研究经验，学生将通过互联网和开放式展览使用UIUC设施进行实验，将增加学生对科学的理解和欣赏。

This Materials World Network project is a joint research and education activity between scientists and students at University of Illinois at Urbana-Champaign and Hahn-Meitner Institute in Germany to study fundamental issue-how the boundaries between crystals in a class of materials known as polar-covalent semiconductors affect their optical and electronic properties. Polar covalent semiconductors such as copper indium diselenide [CuInSe2] and related materials have the greatest potential for ultimate energy conversion efficiency in a large-area device. This research program addresses the primary fundamental science issue currently facing these materials-how do the boundaries between crystals affect the performance of the device. The primary objective of this award is to grow large, thin single crystals of CuInSe2 joined in well-defined grain boundaries that can be studied and modeled in detail. Advanced optical probe methods with nanoscale resolution will be employed to examine the way in which light interacts with the material and how the grain boundary affects the behaviors. The result will be a comprehensive understanding of grain boundaries in polar covalent semiconductors from AlN to ZnSe in general. The crystal growth techniques applied and the general scientific issues studied would have strong implications for a class of materials used in solar cells, and they have been identified as the most promising renewable energy technology for large-scale power generation. The program brings together the leading fundamental science research groups in Germany and at the University of Illinois, and will expand ongoing research activities and greatly increase graduate and undergraduate student exchange. %%%The project could enhance the understanding one of the core unique features of polar covalent semiconductors, namely their ability to function in the presence of structural defects. The results would have potential implications for grain boundary passivation in other semiconductors, and for improvement in optical devices such as photovoltaics, light emitters, and photosensors. International exchange will provide enhanced training and exchange of ideas between researchers including students in the US and Germany. The value added by the international collaboration is in exchange of research techniques to be applied and training of US graduate and undergraduate students in techniques in which the German group specializes. The proposed undergraduate and graduate students interactions with students in K-12 including classroom visits, distance research experiences where students will perform experiments using the UIUC facilities via the internet and open house exhibits would increase the understanding and appreciation of sciences among the students.