SiC 10um-Pitch UV Imaging Array and APD with Active Pixel Readout

CoolCAD Electronics, LLC, proposes to design and fabricate a SiC UV detector array with a 10μm pixel pitch, sensitive to EUV, VUV and Deep UV. SiC is a visible-blind material with very low intrinsic dark current, able to operate at >350C. Expanding from our past successful demonstration of UV sensors and MOSFET circuits on the same substrate, we will develop fabrication processes and capabilities to design and integrate SiC pn-junction photodiodes and low-voltage MOSFET devices with the required small dimensions. To our knowledge, this represents the first program to scale SiC optoelectronic circuits to such feature size restrictions; particularly, a 1μm MOSFET gate length and submicron margins for layer overlaps. Scaling monolithically-integrated sensors and transistors to submicron feature sizes advances the SiC technology state-of-the-art. We plan to extend our process flow and device designs to use a semiconductor reduction stepper during fabrication to enable submicron features. We will demonstrate single pn-junction photodiodes, photodiodes with MOSFETs in the 3-transistor pixel architecture, and arrays of both these structures. We will deliver a 32 x 32 passive array and a 4 x 4 active array that contains SiC MOSFETs as well as photodiodes. This effort lays the groundwork for developing a megapixel array in a future Phase II or related program. We will further design planar SiC avalanche photodiodes and planar APD arrays, as the initial step to monolithically integrating APDs with their readout electronics and therefore obtain a high-temperature-operation-capable detector, sensitive to extremely low illumination levels. The entire design and fabrication will be performed in the United States, and using CoolCAD's patent pending fabrication processes.