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

点击翻译按钮获取中文摘要

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. UT 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.