Research on the Performance of Nuclear Battery with SiC-Schottky and GaN-PIN Structure

The fabrication and experimental research of a GaN-Positive-Intrinsic-Negative (GaN-PIN) betavoltaic nuclear battery driven by an ⁶³Ni radioisotope source and an SiC-Schottky betavoltaic nuclear battery driven by an ¹⁴⁷Pm radioisotope source are introduced. The self-absorption effects of radioisotope sources (⁶³Ni, ¹⁴⁷Pm) are explored and analyzed by Monte Carlo simulation. The SiC-Schottky and GaN-PIN betavoltaic cells were fabricated, where the GaN-PIN devices include different areas, absorption layer thicknesses, and electrode structures. And the measured I–V results show that the power density of the GaN-PIN nuclear battery can exceed 4.3 nW/cm², the open-circuit voltage can reach 1.25 V, and the energy conversion efficiency can reach 2.3%. And for the SiC-Schottky betavoltaic battery, the maximum output power and energy conversion efficiency are 0.67 pW/cm² and 0.024%, respectively.