Collaborative Research: ARI-MA Development of Improved CMT and CZT Nuclear Detectors for Homeland Security Applications

合作研究：ARI-MA 开发用于国土安全应用的改进型 CMT 和 CZT 核探测器

• 批准号: 1140001
• 负责人: Jeffrey Derby
• 金额: $ 12万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1140001&HistoricalAwards=false
• 关键词: Collaborative; Research; ARI; MA; Development

The goal of this project is to develop high-resolution Cadmium Manganese Telluride (CMT) and Cadmium Zinc Telluride (CZT) materials for nuclear and radiological detection applications in homeland security. These materials have emerged as promising advanced detectors for X-ray and gamma-ray spectroscopy and imaging without cryogenic cooling. Advances in research have led to the development of CZT for commercial devices, but there is still the presence of defects such as Tellurium (Te) inclusions that limit the performance of large-volume CZT and CMT detectors that are needed for nuclear and radiological detection applications. The results of this project will provide benefit to society, with high impact on the science and technology of semiconductor nuclear detectors for room-temperature applications in homeland security (maritime and port security, border security, transportation security, nonproliferation and domestic nuclear security). The outcomes also include new capabilities that are very important to the success of emerging detector technologies and analysis tools needed to support next-generation nuclear materials management and safeguards. This project advances discovery and understanding while promoting teaching, training, and learning.The project team will use theory-based design, knowledge-based processing and fabrication, and novel experimental techniques to develop improved cadmium manganese telluride (CMT) and cadmium zinc telluride (CZT) materials for high-resolution nuclear detection applications. The project will enhance the science and expand the overall knowledge in this area by using a combination of theory, modeling and experiments to complete the following tasks: 1) optimization of the Bridgman methods and Traveling Heater Method (THM) for growth of improved CMT and CZT crystals; 2) a novel post-growth annealing and doping process for removing performance-limiting defects caused by tellurium inclusions and associated impurities in CMT and CZT detector materials; and 3) improved surface passivation and detector fabrication techniques to produce better detectors. These methods employ state-of-the-art instrumentations that incorporate 3D-infrared transmission spectroscopy and advanced measurement tools to probe and collect data during the post-growth annealing process. The development of in-situ tools to monitor crystal annealing adds a new experimental dimension that will lead to any improved understanding of the migration of tellurium inclusions and novel methods to minimize their impact on electron trapping. The end result will be CMT and CZT detectors with better resolution, improved detection efficiency and better directional sensitivity. The outcomes from the modeling aspects of this project will provide an understanding of fundamental phenomena associated with Bridgman and THM growth of ternary II-VI compounds and suggestions regarding post-growth treatments to improve the microstructural properties of these crystals. The anticipated impact of in-situ probing and data collection techniques will include new insights into the science and dynamical properties of post-growth annealing, uniform doping of detector materials, migration of Te secondary phases and impurities, and methods to process detector surfaces. This project advances discovery and understanding while promoting teaching, training, and learning. It is multidisciplinary with investigators from the following collaborating entities: Alabama A&M University, University of Minnesota ? Twin Cities, Brookhaven National Laboratory (BNL), FLIR Radiation Inc, and the Interdisciplinary Consortium for Research and Educational Access in Science and Engineering (INCREASE). The workforce development component of this project will provide opportunities for women and under-represented minorities to build careers and earn graduate degrees in areas critical to the development of cutting-edge nuclear and radiological detection technology.

该项目的目的是开发高分辨率的锰醇酯（CMT）和锌锌锌锌（CZT）材料，用于国土安全部的核和放射学检测应用。 这些材料已成为X射线和伽马射线光谱和成像的有希望的高级探测器，而无需低温冷却。 研究的进步导致了商业设备的CZT开发，但是仍然存在缺陷，例如牙花腔（TE）包含物，这些缺陷限制了用于核和放射学检测应用所需的大批量CZT和CMT探测器的性能。 该项目的结果将为社会带来好处，对在国土安全部（海事和港口安全，边境安全，运输安全，非扩散和国内核安全）中对半导体核检测器的科学和技术产生了很大影响。结果还包括新的功能，这些功能对于支持下一代核材料管理和保障措施所需的新兴探测器技术和分析工具非常重要。 该项目在促进教学，培训和学习的同时进步和理解。项目团队将使用基于理论的设计，基于知识的加工和制造，以及新型的实验技术来开发改进的甘g锰蒸馏硫化合物（CMT）和锌醇酸锌醇酸酯（CZT），用于高分辨率核检测应用。 该项目将通过使用理论，建模和实验来完成以下任务的组合来增强科学并扩大该领域的整体知识：1）优化Bridgman方法和行进加热器方法（THM），以增长改进的CMT和CZT晶体； 2）一种新型的生长后退火和掺杂过程，用于消除由trinum夹杂物和CMT和CZT探测器材料中相关杂质引起的性能限制缺陷； 3）改善了表面钝化和检测器制造技术，以产生更好的探测器。这些方法采用了最新的仪器，这些仪器结合了3D-Infrared传输光谱和高级测量工具，以在生长后退火过程中探测和收集数据。 监测晶体退火的原位工具的开发增加了一个新的实验维度，这将导致人们对胎记夹杂物的迁移和新方法的迁移，以最大程度地了解它们对电子捕获的影响。 最终结果将是CMT和CZT探测器，具有更好的分辨率，提高检测效率和更好的方向灵敏度。该项目的建模方面的结果将提供对与Bridgman相关的基本现象和三元II-VI化合物的THM生长的理解，以及有关生长后处理的建议，以改善这些晶体的微观结构特性。 原位探测和数据收集技术的预期影响将包括对生长后退火后科学和动力学特性的新见解，探测器材料的均匀掺杂，TE次级阶段和杂质的迁移以及处理探测器表面的方法。 该项目在促进教学，培训和学习的同时进步和理解。 它是来自以下合作实体的调查人员的多学科：明尼苏达大学阿拉巴马州A＆M大学？双子城，布鲁克黑文国家实验室（BNL），Flir Radion Inc和科学与工程学研究和教育跨学科联盟（增加）。该项目的劳动力发展组成部分将为妇女和代表性不足的少数民族建立职业并赢得研究生学位的机会，并在对尖端核和放射学检测技术发展至关重要的领域中获得研究生学位。