Breakdown enhancement of diamond Schottky barrier diodes using boron implanted edge terminations

Boron implanted edge terminations have been demonstrated to enhance the breakdown voltages and stabilities of diamond Schottky barrier diodes (SBDs). The edge terminations were achieved by boron implant to form nonconductive amorphous regions under the edges of the Schottky contacts. Direct current measurements show the implanted regions did not contribute to the forward currents and high current densities of about 4000 A/cm ² were obtained at −5 V. By using boron implanted edge terminations, although an increase in leakage currents was observed, the average breakdown voltage of the devices was significantly improved from 79 V to 125 V, which is increased by more than 50%. In addition, the breakdown voltages of the devices without edge terminations degraded quickly after each repeating measurement, whereas the devices with edge terminations became much more stable and no obvious drop in breakdown voltages was observed.