Improvements in reverse characteristics of diamond Schottky diodes by neutron irradiation

Diamond is emerging as a promising material for space applications due to its unique properties and potential high performance in extreme environments. In this work, we systematically study the impact of 1 MeV equivalent neutron irradiation on diamond Schottky barrier diodes (SBDs). According to current-voltage (I-V) measurements, the Schottky barrier height (\varPhi_\rm B) of the diamond SBD was increased from 1.23 eV to 1.32 eV, the ideality factor (n) was reduced from 1.88 to 1.66, and the reverse breakdown voltage increased by 100 V after neutron irradiation. Furthermore, the carrier concentration across the diamond drift layer was observed to decrease from 5.91 \times 10^15 cm^-3 to 5.15 \times 10^15 cm^-3 based on the capacitance-voltage (C-V) measurement. Moreover, the low-frequency noise analysis also indicated a decrease. Considering the changes in device performance, the metal/semiconductor interface traps were slightly reduced, and the Schottky barrier was significantly improved.