Novel Approach Toward High Performance Energetic Rays Detection

72853T03-I Ultrafast (sub-nanosecond), ultrahigh spatial resolution (sub-micron), and highly efficient scintillator detectors are required for many time-resolved energetic photon imaging and detection applications. However, current scintillator screens can achieve only spatial resolutions in the tens of microns, response times in the hundreds of nanoseconds, and poor light collection efficiency. Near-band-edge emission semiconductor scintillators possibly could achieve all of the goals above, but the fabrication of high quality materials is still a challenging task. This project will develop a novel fabrication technology for wide bandgap semiconductor scintillator nanocrystal arrays (HgI2, PbI2, and ZnO:Ga). Such arrays potentially could reach sub-micron spatial resolution, increase light output to approximately 200,000 photons per MeV, achieve sub-nanosecond response, and, theoretically, reach 100% light collection efficiency. Phase I will develop large area PbI2 and ZnO-based scintillator nanocrystal arrays as energetic photon detectors. The arrays will be overcoated with optical filling materials, and then subjected to full scintillation characterizations. Energetic photon detection and imaging devices based on this process will be demonstrated. Commercial Applications and Other Benefits as described by awardee: High spatial resolution and fast response speed are key luminescence characteristics for energetic photon and neutron detection and imaging. The nanoarrayed detectors should have extensive application in nuclear detection, dynamic nondestructive tests, fast medical imaging, macro-crystallography, and fundamental research areas where resolution and speed are important.