Quantitative modeling of betavoltaic microbattery performance

This paper presents a simulation model to predict the power generation of p-n junction-based betavoltaic devices. The model provides two key aspects of information for device evaluation: electron-hole pair generation rate and device power output. A Monte-Carlo model was used to simulate generation rate and the device performance was simulated using the generation rate with Synopsys® Medici. We investigated the effects of the temperature, semiconductor materials with different bandgap energies (Si, Ge and SiC) and different isotope sources (Ni-63 and tritium) on the performance of betavoltaic microbatteries. Our simulation results indicate that a homojunction structure with wide bandgap semiconductor is more favorable for betavoltaic device performance. A simple wide bandgap p-n junction cell with an embedded radioisotope source could be the most promising candidate for betavoltaic applications.