Analysis on electrical performance of GaN and Si diodes as betavoltaic batteries energy converters

Background: Betavoltaic battery is a hot spot in micro isotope batteries due to its advantages of small volume, maintenance-free, high energy conversion efficiency, ease of integration and so on. GaN is a promising wide bandgap semiconductor for energy converter of betavoltaic battery. Purpose: This study aims to explore the performance of GaN diode as the energy converter of betavoltaic battery, and to compare it with the performance of Si diode. Methods: Two kinds of GaN and Si PiN diodes were prepared to be the energy converters of betavoltaic batteries, and irradiated by ⁶³Ni and ³H radioactive sources. Their electrical performances, temperature and irradiation tolerance, were compared. Results: The results showed that the V_oc of GaN diode was higher than that of Si diode, while I_sc was lower; the electrical performance of GaN diode under the conditions of high temperature and high energy irradiation were better than that of Si diode. Conclusion: GaN diode could increase the V_oc of betavoltaic battery, and improve electrical performance under high temperature and high energy irradiation conditions. (authors)