The perspectives of diamond for 3H and 63Ni betavoltaic power sources, comparison with 4H–SiC

Recently, power sources that utilize radioisotope energy conversion, specifically the betavoltaic effect, have gained more attention due to the increasing demand for energy-efficient technologies in new electronics. These power sources are capable of delivering electrical power continuously over periods of years. Among various semiconductors, 4H–SiC and diamond are the most desirable materials for building betavoltaic structures. Although 4H–SiC betavoltaics are commercially available and have been demonstrated, diamond is still an emerging material. However, recent advancements in diamond technology, such as the demonstration of bipolar structures—a necessary requirement for high-efficiency betavoltaics—make it a promising candidate for building practical betavoltaic devices in the near future. This study aims to evaluate the potential of diamond bipolar structures for betavoltaic applications using 3H and 63Ni sources and compare the results with 4H–SiC at both room and elevated temperatures, taking into account the current level of materials technology development. The electrical parameters of these structures are estimated using the Monte Carlo transport tool GEANT4 coupled with the finite-element device simulator TCAD SILVACO. The simulation results are compared with existing experimental data for both 4H–SiC and diamond devices.