This Small Business Innovation Research Phase I project addresses the fundamental issues limiting the applications of Cadmium-Zinc-Telluride/Cadmium Telluride radiation detectors. Currently, x-ray and gamma ray equipment industry producing medical imaging, manufacturing, and security inspection instrument is a multi-billion dollar business. Room temperature Cadmium-Zinc-Telluride/Cadmium Telluride detectors and arrays appear to be the obvious choice as the sensing elements. However, after forty years of research, many problems remain. It was not clear why the yield in producing Cadmium-Zinc-Telluride/Cadmium Telluride detectors is still so low. Based on semiconductor physics, two parameters are most crucial in determining the detector performance: the need of the deep level of donor or acceptors to pin the Fermi level near the middle of the bandgap and the necessity to avoid defects which trap the carriers. Potential commercial applications of the research can be used by researchers at accelerator laboratories for particle analysis, by scientists for crystallography, by security personnel for inspection, by engineers for the control of packaging such as bottling, and for numerous medical applications.