Detecting MEV photon energies and neutrons generally relies on single crystal devices, which are either a expensive to manufacture, b limited in spectroscopic performance, c have limited survivability…

Detecting MEV photon energies and neutrons generally relies on single crystal devices, which are either a expensive to manufacture, b limited in spectroscopic performance, c have limited survivability for field operations, or d a combination of the three and are therefore prohibitive to deploy as either ubiquitous hand held units or as large area single instruments recently, polycrystalline semiconductors have gained academic interest as an alternative to single crystal devices due to their substantially lower manufacturing costs and relative ease of scalability however, device performance is generally limited to x RAY photon energy regimes due to large rates of bulk charge carrier recombination at grain boundaries which substantially reduces charge collection efficiency in addition, current leading candidates for next generation room temperature detectors, namely metal halide perovskites, currently suffer from poor device stability due to high ionic mobility and limited environmental stability in order to enable the development of disruptive advancements in polycrystalline MEV photon and neutron detectors, new materials, manufacturing methods, and device integration strategies need to be developed that 1 limit bulk charge carrier recombination, 2 reduce detector noise, 3 increase environmentally stability, 4 utilize scalable manufacturing techniques, and 5 demonstrate high detection resolution for both dose rate and spectroscopy applications this program aims to revolutionize state of the art ionizing radiation detectors by developing wide band GAP, polycrystalline based semiconductors fabricated via field assisted sintering technology fast new material systems will be explored via first principles density functional theory DFT and machine learning techniques to identify new wide band GAP compound semiconductors with high radiation detection sensitivity and environmental stability these new material systems will be synthesized and fabricated into polycrystalline detectors via fast, a relatively new, scalable manufacturing technique, which can consolidate semiconducting powder on a timescale of minutes to sizes up to 14 diameter and several inches in thickness compared to competing sintering technologies i e conventional sintering, hot isostatic pressing , fast offers substantially shorter process times minutes compared to hours and microstructural tailorability enabling low cost fabrication of large area detectors processing parameters will be optimized to enhance microstructure attributes such as grain size, texture and porosity, as well as tailored grain boundary chemistry to reduce bulk recombination and enhance charge collection efficiency this will enable polycrystalline based devices to spectroscopically detect MEV photons with efficiency that rivals current state of the art detectors additional compositional tailoring, including doping structures with boron or lithium, are expected to enable neutron detection capabilities finally, device architectures will be engineered for surface leakage suppression to reduce noise, and readout technology will be developed to enhance detection signal for application into personal dosimeters, dose rate meters, and or spectrometers the proposed program aims to accomplish these research goals while also providing multidisciplinary stem education and outreach to students from traditionally underrepresented groups this research is expected to have a dramatic impact on the cwmd mission for detecting nuclear materials as IT will enable a new class of polycrystalline based devices for high energy photon detection and neutron detection, which offer substantially lower processing costs and increased scalability compared to current state of the art technologies