Effects of Neutron Irradiation on Electrical Performance of β-Ga₂ O₃ Schottky Barrier Diodes

The effect of neutron irradiation on the electrical performance of the $\beta $ -Ga2O3 Schottky barrier diode (SBD) device has been studied in this work. After equivalent 1 MeV neutron irradiation with a fluence of $1\times 10^{{14}}$ n/cm2, a 20% decrease in the forward current density ( ${J}_{\text {F}}{)}$ , a 75% reduction in the reverse current density ( ${J}_{\text {R}}{)}$ , and a 300 V increase in the breakdown voltage ( ${V}_{\text {br}}{)}$ have been observed according to current–voltage ( ${I}$ – ${V}{)}$ measurements. Utilizing the frequency-dependent conductance technique, it is found that the density of interface states located at Pt/Ga2O3 increases slightly from $2.6\times 10^{{12}}$ – $6.4\times 10^{{12}}$ to $2.9\times 10^{{12}}$ – $7.0\times 10^{{12}}$ cm $^{-{2}}$ eV $^{-{1}}$ with an increase in trap activation energy from 0.09–0.122 to 0.096–0.134 eV after neutron irradiation. Furthermore, based on the capacitance–voltage ( ${C}$ – ${V}{)}$ measurement, it is observed that the carrier concentration across the Ga2O3 drift layer was decreased from $1.80\times 10^{{16}}$ to $1.35\times 10^{{16}}$ cm $^{-{3}}$ after neutron irradiation. Considering the device performance change, it indicates that the bulk traps within the Ga2O3 drift layer instead of interface states dominate the device degradation.