Optimal Radiation Tolerant High Intensity High Temperature Photovoltaics

In this SBIR Phase 1 project, we propose the development of a photovoltaic (PV) cell offering both high-intensity high temperature (HIHT) and low-intensity high temperature (LIHT) using silicon carbide (SiC) grown by MOCVD. The HIHT PV cells and blanket technologies will be used for near Sun missions and the LIHT will be used in missions such as Venus surface operation. We will use our proprietary technology building on two NASA patents to grow the cubic SiC (3C-SiC) based PV cell structure. In Phase I, we will demonstrate a single junction PV cell. Cubic 3C-SiC is considered a perfect material for high-temperature PV operation because of its thermal stability and because its band gap decreases from ~2.7eV at room temperature to ~2.2eV as the temperature increases to ~770deg;C. Additionally, 3C-SiC theoretically offers a room temperature efficiency as high as 45-60% with boron interband; vs ~30% for a standard cell. In Phase I, we will first focus on demonstrating a baseline refining its growth, PV processing and characterization will span from room temperature to 500deg;C operation. Further, we will also demonstrate the nascent boron doping formation of an interband structure that we will optimize for each of HIHT and LIHT operations. Phase III will focus on providing mission implementation cells. We will leverage our growth expertise to further optimize the growth of 3C-SiC for this projectrsquo;s requirements. The Phase II project goal is to show the boron effect compared to a standard cell and to achieve efficiencies gt;30% at 450deg;C.