Alphavoltaic energy conversion, in which an alpha particle flux from radioisotope sources such as Am-241 is converted into electrical power through a semiconductor junction, offers the promise of a higher power output as compared to the more established betavoltaic systems. Semiconductors coupled to alpha particle irradiation, however, are susceptible to degradation from point defect damage and consequently suffer from reduced power output and operational lifetime. The ternary AlGaN alloy system, due to its high bandgap energy, density, and melting point, is a promising semiconductor system for stable alphavoltaic energy conversion. In this work, AlGaN is explored as a materials basis through both band modeling and combined MBE and MOCVD materials growth of GaN/AlGaN heterojunctions incorporating graded and doped layers. These combined studies and designs work towards a goal of achieving a stable high-power output alphavoltaic device based on the AlGaN materials system.
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