Development of a Large-Area Mercuric Iodide Photodetector for Scintillation Spectroscopy

61036 This project will develop HgI2 photodetectors, used in nuclear physics research, with resolution better than 6% for 662 keV. In Phase I, a process for manufacturing HgI2 photodetectors was developed. The detectors had a Full Width Half Max (FWHM) resolution between 5.6% and 6.6%, with an average of 6.2% FWHM for 9 out of 10 operational units produced. Phase II will fine tune performance and commercialize the process with formalized process control and quality assurance monitoring. 100 HgI2 detectors will be manufactured in 14 process change steps, where each step in the process addresses optimization of functional and appearance design considerations. All units will enter a longevity study, which will provide data for process control and quality assurance for detectors yielding FWHM resolution of 5.5%, or better. Commercial Applications and Other Benefits as described by the awardee: The technology should replace bulky and less efficient photomultiplier tupes used for intermediate energy room temperature nuclear spectroscopy. HgI2 replacement units would not be susceptible to magnetic fields and would be ruggedized for nuclear assay field uses. There is also a potential for medical applications.