Work

Optimal Selection and Experimental Verification of Wide-Bandgap Semiconductor for Betavoltaic Battery

Year: 2025

Type: article

Abstract: Wide bandgap semiconductor betavoltaic batteries have a promising prospect in Micro Electro-Mechanical Systems for high power density and long working life, but their material selection is still controversial. Specially, silicon carbide (SiC) betavoltaic battery was reported with higher efficiency although its bandgap is lower than that of gallium nitride (GaN) or diamond, which is inconsistent with general assumption. In this work, the effects of different semiconductor characteristics on battery energy conversion process are systematically analyzed to explain this phenomenon, including beta particle energy deposition, electron–hole pair (EHP) creation energy and EHPs collection efficiency. Device efficiencies of betavoltaic battery using SiC, GaN, diamond, gallium oxide (Ga2O3), aluminum nitride (AlN) and boron nitride (BN) are compared to determine optimum semiconductor. Results show that SiC for betavoltaic battery has higher efficiency than GaN, Ga2O3 and AlN because of higher EHPs collection efficiency, less energy loss and fewer material defects, which is optimal selection currently. SiC betavoltaic batteries were prepared, with device efficiency reached 14.88% under electron beam and device efficiency as 7.31% under isotope source, which are consistent with the predicted results. This work provides theoretical and experimental foundation for material selection of betavoltaic batteries.

Source: Nanomaterials

DOI: 10.3390/nano15090635