Investigation of heavy-ion induced degradation and catastrophic burnout mechanism in SiC diode

Irradiation experiment and simulation of 205-MeV Ge ion and 283-MeV I ion were used to analyze the single event leakage current (SELC) and the single event burnout (SEB) mechanism of SiC diode. Under two selected heavy ion irradiations, the ampere-magnitude pulse current were generated along with the occurrence of SEB. The SEB area was found to cover the anode metal, epitaxial layer and substrate in microscopic analysis, which resulted in damage to the forward and reverse characteristics of device. Devices were irradiated by 205-MeV Ge ion with a fluence of 5 × 10⁶ n·cm⁻², under 200 V and 300 V reverse bias voltages, the breakdown voltage were degraded by 70 % and 82 % respectively. The anode contacts of SELC devices had local fractures and displacements, which led to the degradation of breakdown characteristics. Combined Monte Carlo simulation and TCAD simulation, the SEB critical temperature appeared near the anode contact firstly when the two selected heavy ions were incident. When the two selected heavy ions were incident from Schottky and Ohmic contacts at a bias voltage of 200 V, excessive temperature in local areas and temperature differences between different anode materials caused the fractures and displacements of anode contact.