HIGH-VOLTAGE DIAMOND SCHOTTKY RECTIFIERS

摘要

In this paper, we simulate and fabricate diamond schottky rectifiers. The growth rate of pure diamond single crystal epitaxial is from 0.5 up to 100 μm/hr with boron doping concentration around 1x1014 cm-3 to 1x1016 cm-3. A "liftoff" technology is used to provide the wafer. Theoretical calculation indicates that the diamond shottky rectifier has a significant lower voltage drop than SiC schottky rectifier and comparable with SiC PiN diode with the blocking voltage higher than 10 kV. A maximum 50 kHz operating frequency at switching voltage 25 kV is shown based on thermal limit. Vertical structure devices with 70μm epi layer achieve 18 A/cm~2 at 250℃ at 7 V forward drop as shown with a breakdown voltage of only 600 V. A breakdown voltage of 8 kV at 100 μm distance is recorded for lateral structure devices without ohmic contact (back to back Schottky diodes), 12.4 kV at 300 μm distance.