NSF Award
0320023
This Small Business Innovation Research (SBIR) Phase I project will develop a novel, solid state, avalanche photodiode operated in Geiger mode as single photon sensitive avalanche detector (SPAD). Phase I will experimentally confirm the theory and quantitatively prove the suitability of a device structure and materials choice. Phase II will optimize and implement a high performance SPAD. The novel SPAD will have better single photon sensitivity, quantum efficiency, and response speed than the best vacuum photomultiplier tube (PMT) or silicon SPAD. The photodetector will be fabricated using novel large band gap compound semiconductor materials, which exhibit exceptionally low dark count rates and high materials quality. The novel materials promise a thermal generation rate 50 million times lower than that of the silicon commonly used for SPADs, and has higher carrier velocities and a direct band gap. Together, these promise quantum efficiencies above 50 percent, sub-nsec rise times, nsec reset times, and psec jitter. The project will obsolesce the PMT and silicon SPAD for photon-starved applications using them in biology, chemistry, physics, astronomy, and remote sensing. The project helps both research and instrumentation.<br/><br/>The ability to detect single photons with high detection efficiency, low dark count rate, high sensitivity, high timing resolution, and high duty cycle is a key requirement for many scientific instruments and sensing/detecting applications. The development of a robust, solid state, single photon avalanche detector (SPAD) will transform such components from expensive laboratory curiosities requiring liquid nitrogen or high voltage glass tubes into commonplace parts. New applications with small markets today, such as single photon quantum communications and lab-on-a-chip, could also benefit greatly.
