In the proposed Phase I SBIR program, Aymont Technology and CoolCAD Electronics will design and demonstrate prototype silicon carbide (SiC) avalanche photodiodes (APD) specifically designed for high-efficiency, single-photon counting of 121.6 nm Lyman-alpha photons. This detector will be provided to relevant personnel at NIST for calibration and testing. Both discrete APDs and arrays will be used to enable a 3 x 5 mm detector suitable for this prototype testing. The proposed research will build upon Aymonts demonstration of a SiC APD with over one million multiplication gain and CoolCADs extensive modeling of 4H-SiC APDs for 135 nm applications. An absorption layer on the order of 10 nm thick will be used in Phase I to reduce wavelength and enable at least 5% quantum efficiency at the Lyman-alpha characteristic wavelength. Commercial Applications: The APDs to be developed on this program can be used for a host of potential applications in the far ultraviolet. Most relevant for this particular research is its use in the Lyman Alpha Neutron Detector (LAND) recently developed at NIST. This detector can be used in place of a photomultiplier tube to efficiently detect neutrons in simple, compact, and potentially low-cost configuration. Additional applications for the APDs not involving neutron detection include space astronomy, far ultraviolet spectroscopy, and photolithography. Development of these 4H-Sic APDs for the LAND detector will also further the development of these APDs for the solar blind regime, where they can be used for medical imaging, biodetection, non-line-of-sight communications, and to replace PMTs in scintillation detection (e.g. handheld radiation detection).
