ARI-MA: Design and Growth of High Density, Wide Band-Gap Semiconductor Materials

该项目研究了专门设计用于高分辨率室温识别裂变材料发出的α射线的新型材料的使用。这项工作将提高具有相对较宽能隙的高密度重元素半导体的科学水平和知识体系。拟议的项目具有本质上变革的潜力，因为它将使用基于“降维”概念的材料设计新理念来识别用于敏感α射线检测的新材料。的共价框架。使用晶体生长技术，我们将生长和研究各种半导体化合物，以验证它们的能隙和电阻率。 所需材料需要约 108 Ohm-cm 的最小室温电阻率，以便应用更大的偏置，从而在检测装置中实现更快的载流子漂移速度和更深的耗尽深度。对于最高 Z 值的材料，通过选择此处提出的硫属化物等化合物，也可以大幅降低所谓的 Fano 噪声（从而提高能量分辨率）。这些材料将以晶体和器件形式进行表征和测试，以进行 射线检测。 基于理论的材料设计将在很大程度上取决于基于知识的高 Z 宽带隙半导体所需性能的优化。选择过程和实验方法也将密切依赖理论指导。 这是综合、测量和理论之间密切的跨学科合作，涉及具有互补技能的团体。

This project investigates the use of novel materials specially designed for high resolution room-temperature identification of ã-rays emitted from fissile materials. This effort will enhance the state of the science and body of knowledge for highly dense, heavy element semiconductors with relatively wide energy gaps. The proposed project has the potential to be transformative in nature because it will identify new materials for sensitive ã-ray detection using a new idea for materials design based on the concept of ?dimensional reduction? of covalent frameworks. Using crystal growth techniques, we will grow and survey a variety of semiconducting compounds to validate their energy gaps and their resistivity. A minimum room temperature resistivity of ~108 Ohm-cm is required in the desired materials in order to allow for larger biases to be applied, resulting in faster carrier drift velocities and deeper depletion depths in the detection device. For the highest Z materials, the so-called Fano noise can also be substantially decreased (and thus energy resolution improved), by choosing compounds such as the chalcogenides proposed here. The materials will be characterized and tested in both crystal and device form for ã-ray detection. Theory-based materials design will depend strongly on knowledge-based optimization of the desirable properties of high Z wide gap semiconductors. The selection process and experimental approach will also rely closely on theoretical guidance. This is a close interdisciplinary collaboration between synthesis, measurement and theory involving groups with complementary skills.