Monte Carlo simulation for evaluating the attenuation effects of a protective layer for a Ni-63 nuclear battery

Abstract

Interest in the use of betavoltaic nuclear batteries has grown substantially in recent years for its potential use in new generation of microelectromechanical systems. Ni63 is the promising because of: pure beta source, long half-life (about 100 years), and low energy beta particles. Temperature test up to 180 °C is mandatory for source validation. This can cause the radioactive material to leak. To prevent leakage, a protective layer must be placed between the radioactive source and the transducer (diode). The main goal of this work is to use computer simulation to quantify the amount of particles that would be loss if a protective layer is placed between the p-i-n diode and the source. Results compared SiO2, SiN, and diamond as materials and a protective layer thickness from 60 nm to 2 μm. Only 29.4% of the total particle number is contributing to power generation. This is important because it gives a real estimate of how much will be used to generate the final power output.