Collaborative Research: ARI-MA: Very large area, high sensitivity neutron detection system

该计划的总体技术目标是研究开发超大面积、坚固耐用、高灵敏度、低功耗、像素化的热中子探测器所需的科学和技术。大面积探测器系统，一侧有仪表，提供了快速扫描高灵敏度的大型集装箱所需的大孔径。有三个技术领域将被解决，以满足这些目标：1）中子转换层，2）带电粒子检测层，和3）高灵敏度有源矩阵像素电子器件，用于低寄生电容检测和信号放大，以允许大阵列。 对于这三种技术中的每一种，我们都将采用多种方法来提供性能和可靠性。 对于中子转换层，我们的第一种方法是评估分散在聚合物基基质中的含有硼-10和/或锂-6的纳米颗粒，该聚合物基基质与薄膜传感器（二极管上转换器）接触。 我们的长期方法是评估分散在溶液可加工半导体二极管（二极管中转换器）中的含有硼-10和/或锂-6的纳米颗粒。 对于带电粒子探测系统，我们将对带电粒子在薄膜半导体二极管中引起的电流产生和收集有基本的了解。 为了最大限度地提高灵敏度，同时保持选择性，我们将开发高灵敏度像素电子器件，这将需要非常低的噪声放大器。我们将评估基于薄膜晶体管的新型放大器设计。 该项目的一个重要目标是开发模型来模拟设备性能，以及系统性能，以评估系统在不同探测场景下的灵敏度。由于氦-3的供应迅速减少，需要一种新的中子探测技术。 我们的项目将开发一种新型的热中子探测系统，该系统将提供核威胁探测中前所未有的性能。 总体概念基于这样的想法，即总体灵敏度与探测器的面积成比例，并且总体选择性与假阳性的比例与通过像素化探测器来定位中子源的能力成比例，从而增加信噪比。 因为所提出的技术与平板显示器制造技术兼容，所以检测器应该相对便宜。 此外，由于所有提出的工艺都与低温塑料基板兼容，因此坚固性是设计中固有的，而不是事后的想法。 该计划的一个重要组成部分是本科生，研究生和博士后学生的培训，他们将学习核威胁检测，从中子和带电粒子与物质的基本相互作用到测试设备的灵敏度和辐射硬度，这是一个几乎没有学生的机会。 作为培训的一部分，我们将开发一系列课程，可以在高级本科生/研究生水平上授课，也可以作为核探测工作人员的短期课程。位于达拉斯的德克萨斯大学和亚利桑那州立大学已经合作开发这些大面积热中子探测器，并与陆军研究实验室密切合作。 原型将在亚利桑那州立大学的柔性显示中心制造，提供了一条使该技术可用的途径。

The overall technical goal of this program is to study the science and technology needed to develop very large area, rugged, high sensitivity, low power, pixilated, thermal neutron detectors. Very large area detector systems, meters on a side, provide the large aperture needed to quickly scan large containers with high sensitivity. There are three technology areas that will be addressed to meet the goals; 1) the neutron conversion layer, 2) the charged particle detection layer, and 3) the high sensitivity active matrix pixel electronics for low parasitic capacitance detection and signal amplification to allow large arrays. For each of the three technologies there are multiple approaches we will pursue to provide both performance and reliability. For the neutron conversion layer our first approach is to evaluate nanoparticles containing Boron-10 and/or Lithium-6 dispersed in a polymer-based matrix in contact with a thin-film sensor (converter-on-diode). Our longer term approach is to evaluate nanoparticles containing Boron-10 and/or Lithium-6 dispersed in a solution processable semiconductor diode (converter-in-diode). For the charged particle detection system we will develop a fundamental understanding for the current generation and collection in thin-film semiconductor diodes induced by charged particles. To maximize sensitivity while maintaining selectivity we will develop high sensitivity pixel electronics, which will require very low noise amplifiers. We will evaluate new amplifier designs based on thin-film transistors. A significant goal of this project will be developing models to simulate device performance, as well as system performance to evaluate system sensitivity for different detection scenarios.Because of the quickly dwindling supply of Helium-3 a new neutron detection technology is needed. Our project will develop a novel thermal neutron detection system that will provide performance never seen before in nuclear threat detection. The overall concept is based on the idea that overall sensitivity scales with the area of the detector and that the overall selectivity vs. false positives scales with the ability to locate the source of the neutrons by pixelating the detector, increasing the signal-to-noise. Because the proposed technologies are compatible with flat panel display manufacturing technology, the detectors should be relatively inexpensive. Also, because all of the proposed processes are compatible with low temperature plastic substrates, ruggedness is inherent in the design, rather than an afterthought. A significant part of the program is the training of undergraduate, graduate and post-doctoral students that will learn about nuclear threat detection all the way from the fundamental interactions of neutrons and charged particles with matter to testing devices for sensitivity and radiation hardness, an opportunity available to few students anywhere. As part of the training we will develop a series of classes that can be taught at the senior undergraduate / graduate level, or as a short course for people working in nuclear detection. University of Texas at Dallas and Arizona State University have teamed to work together to develop these large area thermal neutron detectors, with close collaboration with the Army Research Labs. Prototypes will be fabricated in the Flexible Display Center at ASU, providing a path to making the technology available.