For many decades photomultiplier tubes PMTs) have been the main technology for sensitive and low noise detection of photons in many high energy physics experiments. However, compared to solid-state photodetectors, PMTs are bulky, fragile, and need to be shielded from high magnetic fields and high pressures, which severely limit their application for future DOE projects. Hence, there is a need for high sensitivity photon-counting detectors that can address some of the limitations of PMTs. In the past few decades, GaN-based avalanche photodiode APDs) have been investigated as a robust and low-cost alternative to PMTs. However, these APDs suffer from early breakdown voltages due to a large density of defect in GaN materials deposited on typical non-native substrates, such as sapphire or silicon. This problem greatly reduces the detection sensitivity of GaN photodetectors and limits their use for DOE projects, such as Cherenkov detectors, as well as other scientific and commercial applications. In recent years, there has been intense interest in oxide semiconductor materials for future device applications. In particular gallium-oxide Ga2O3), and its alloys with aluminum and indium, have generated lot of interest for power electronic and optoelectronic applications in harsh environments because of their properties including a very large direct bandgap, very high breakdown filed, and excellent chemical and thermal stability and radiation hardness. In this SBIR program, Qrona Technologies Qrona) is teaming up with experienced research groups at the University of Central Florida and University of Michigan in order to develop novel high-performance metal-oxide photodetectors MOPDs) for visible to UV, single-photon detection and imaging in DOE high energy and nuclear physics experiments. In addition to DOE applications in high energy and nuclear physics experiments, high sensitivity and robust photodetectors and imagers in the UV to visible range have a wide range of commercial, military, and scientific applications. Some examples are space-based astronomy, spectroscopy, gamma radiation monitoring in deep well drilling, oil spill monitoring, medical imaging, missile tracking, flame and electric arc sensing, chemical and biological hazard monitoring, and secure optical communications.
