Knowledge Exchange in AlGaAs X-ray detectors - resubmission

理想的X射线能谱成像系统探测器应具有100%的探测效率、几微米的空间分辨率和几eV的光谱分辨率。它还应该具有低功耗，并能够在广泛的温度范围和苛刻的辐射环境中运行。相比之下，现有的硅X射线探测器具有较低的辐射耐受性限制，并且需要热冷却来进行X射线光谱分析。因此，需要具有良好的空间和能量分辨率、良好的辐射耐受性以及能够在不需要外部冷却的情况下在室温或更高温度下工作的探测器。对于许多光谱应用来说，对于入射能量在1到10keV之间的软X射线光子来说，高的量子效率是必不可少的，因为在这个范围内，元素Na(Z=11，Ek=1.04keV)到Zn(Z=30，Ek=8.64keV)有它们的K壳层发射线。基于宽禁带(&gt；2 eV)半导体材料的新型探测器具有克服硅的光谱、温度、辐射和电压限制的潜力。AlGaAs就是这样一种材料，基于这种材料的探测器可以在医疗和小动物成像、实时肢体剂量测量以及环境监测(如石油污染物的X射线荧光分析)等领域得到应用。AlGaAs探测器还应能够在恶劣的辐射环境中工作，例如与石油勘探和火山研究以及未来的行星飞行任务和/或着陆器有关的环境。在过去两年中，两个学术小组(莱斯特大学空间仪器小组和谢菲尔德大学雪崩光电二极管小组)一直在探索将宽带隙半导体用作X射线和紫外光光子计数探测器。莱斯特和谢菲尔德的合作已经制作并测量了简单的AlGaAsPIN二极管的性能。在率先使用AlGaAs传感器作为室温X射线探测器之后，我们现在认为，现在是时候寻求资金，加快两个小组之间的知识交流，以保持来之不易的科学和商业领先地位。Centronic Limited是一家中小型企业，在辐射探测器方面拥有广泛的产品组合，适用于各种要求苛刻的应用。该公司生产用于监测阿尔法、贝塔、伽马、X射线和中子辐射的探测器。这些探测器是为适应各种要求苛刻的应用而设计的，然而，这些应用主要是非成像或光谱的。对AlGaAs探测器的使用将打开新的商业利润丰厚的市场。他们最近向美国扩张，在休斯顿Centronic LLC开设了一家分支机构，这将增加技术转移的机会。这项工作的知识交流方面是该项目的主要目标，这些方面将与商业合作伙伴Centronic有限公司合作开发。一些知识交流成果概述如下：莱斯特大学1)获得X射线和粒子探测的新技术2)了解半导体材料3)了解制造工艺4)宽禁带半导体独有的商业和科学机会谢菲尔德大学1)获得高分辨率X射线探测器的专业知识2)了解X射线光子计数探测器3)了解光谱成像4)建立X射线测试设施5)探测器的新出口-医疗、汽车、和空间仪器。Centronic Limited 1)获得新技术2)新市场机会。特别是在石油工业和医疗保健中使用辐射探测器。3)成像X射线光谱学的新知识一个成功的项目将生产出在许多领域都有应用的传感器，可能会对英国的医疗保健(通过更好的医学老年人)和环境研究带来好处。

The ideal detector for X-ray spectroscopy imaging system would have 100% detection efficiency, spatial resolution of a few microns, and spectral resolution of a few eV. It should also have low power consumption and be able to operate over a wide range of temperatures and in demanding radiation environments. In contrast, available Silicon X-ray detectors have low radiation tolerance limitations and demand thermal cooling for X-ray spectroscopy. Hence there is a need for detectors that have good spatial and energy resolution, good radiation tolerance and can operate at or above room temperature without the need for external cooling. For many spectroscopic applications high quantum efficiency for soft X-ray photons with incident energies between 1 and 10 keV is essential since it is in this range where the elements Na (Z = 11, Ek = 1.04 keV) to Zn (Z = 30, Ek = 8.64 keV) have their K-shell emission lines. New detectors based on wide bandgap (> 2 eV) semiconductor materials have potentials to overcome the spectroscopic, temperature, radiation and voltage limitations of silicon. AlGaAs is one such material and detectors based on this material could find applications in areas such as medical and small animal imaging, real time extremity dosimetry as well as environmental monitoring such as X-ray fluorescence analysis of oil contaminates. AlGaAs detectors should also be able to operate in harsh radiation environments such as those associated with oil exploration and volcanic studies as well as future planetary missions and/or landers. Over the last two years the two academic groups (Space Instrumentation Group, University of Leicester and the Avalanche Photodiode Group, University of Sheffield) have been exploring the use of wide band gap semiconductors for use as X-ray and UV photon counting detectors. The Leicester - Sheffield collaboration have fabricated and measured the properties of simple AlGaAs pin diodes. Having pioneered the use of AlGaAs sensors as room temperature X-ray detectors we now believe that it is timely to seek funds to accelerate the knowledge exchange between the two groups to maintain the hard won scientific and commercial lead. Centronic Limited is a SME which has a wide portfolio in radiation detectors for a range of demanding applications. The Company produces detectors for monitoring of alpha, beta, gamma, X-ray and neutron radiation. These detectors are designed to suit a wide range of demanding applications, however, these are primarily non-imaging or spectroscopic. Access to AlGaAs detectors will open new and commercially lucrative markets. They have recently expanded into the USA, opening a branch in Houston, Centronic LLC which will increase the technology transfer opportunities. The Knowledge Exchange aspects of this work are key objectives of the project and these will be developed in collaboration with the commercial partner, Centronic Ltd. Some of the Knowledge Exchange outcomes are summarised below: University of Leicester 1) Access to new technology for X-ray and particle detection 2) Understanding of semiconductor materials 3) Understanding of fabrication processes 4) Commercial and scientific opportunities unique to wide band gap semiconductors University of Sheffield 1) Access to expertise in high resolution X-ray detectors 2) Understanding of X-ray photon counting detectors 3) Understanding of spectroscopic imaging 4) Establishing a X-ray testing facility 5) New outlets for detectors - medical, automotive, and space instrumentation. Centronic Limited 1) Access to new technology 2) New market opportunities. in particular using radiation detectors for the oil industry, and healthcare. 3) New knowledge in imaging X-ray spectroscopy A successful project will produce sensors that have applications in many areas, with potential benefits for healthcare in the UK (through better medical senors) and environment studies.