CoolCAD Electronics, LLC, is proposing the design and fabrication of silicon-carbide based active pixel sensor, comprising a very LARGE AREA SiC UV photodiode (>4mm2 in Phase I and >4cm2 in Phase II) with a monolithically-integrated readout circuit. SiC photodiodes offer advantages in sensitivity, low dark current, high temperature operation, and higher UV responsivity compared to other commercial UV detector technologies such as GaP. These sensors have applications relevant to Earth and planetary sciences and heliophysics-focused NASA missions. Our technical objectives are the fabrication of very large area SiC photodiodes, in fact larger than what is currently commercially available, and monolithically integrating them with readout circuit components to extend the manufacturability benefits of Si CMOS to the SiC UV sensor arena. As deliverables, we propose to fabricate and deliver large area photodiodes, readout circuit components such as JFETs, and an integrated large area sensor/readout active pixel. We will design the photodiode and other circuit components from the ground-up, with process and electrical performance simulations forming the bases of the structural and fabrication step design, including the development of models for use in circuit simulators. We will optimize and perform the fabrication steps, and electrically and optically characterize the fabricated components using our in-house UV test system.