The Impact of Process Conditions on Surge Current Capability of 1.2 kV SiC JBS and MPS Diodes

Abstract

This paper demonstrated the impact of process conditions on the surge current capability of 1.2 kV SiC junction barrier Schottky diode (JBS) and merged PiN Schottky diode (MPS). The influence of ohmic contact and defect density produced by implantation was studied in the simulation. The device fabricated with high temperature implantation had less defect density in the implant region compared with room temperature implantation, which contributed to higher hole injection in surge current mode and 20% surge capability improvement. In addition, with lower P+ ohmic contact resistance, the device had higher surge capability. When compared to device fabrication with a single Schottky metal layer in the device active area, adding additional P+ ohmic contact on top of the P+ regions in the device active area resulted in the pn junctions sharing a greater portion of surge current, and improved the devices’ surge capability by ~10%.

Design and simulation of high performance β-Ga2O3 super barrier rectifier with a current blocking layer

“…In figures 11(a) and (c), an interesting phenomenon can be found that the peak value of both voltage and current will shift to the left. A similar phenomenon is also observed in 4 H-SiC MPS diode [35]. From the perspective of the resonant circuit, CSBR can be considered as a variable resistance.…”

The effect of wafer thinning and thermal capacitance on chip temperature of SiC Schottky diodes during surge currents

“…This chip-temperature model, given by Eqs. (10) and (11), is verified by experimental data in the following section.…”

“…However, in addition to the thermal resistance, another fundamental parameter that impacts the SiC chip temperature is the thermal capacitance. As a result of wafer thinning practices, the thermal capacitance of the SiC chip is reduced, which has an opposing effect to the thermal resistance in terms of the SiC chip temperature during surge-current events.The capability of Schottky diodes to withstand surge currents has been extensively reported in published literature, as it is regarded as one of the most significant reliability factors of power devices [10][11][12][13][14][15][16][17][18][19] . However, the association between wafer thinning and the surge-current capability of a Schottky diode is a novel field of research, with studies predominately reporting on the beneficial influence of wafer thinning as a way of enhancing the surge-current capability.…”

“…The capability of Schottky diodes to withstand surge currents has been extensively reported in published literature, as it is regarded as one of the most significant reliability factors of power devices [10][11][12][13][14][15][16][17][18][19] . However, the association between wafer thinning and the surge-current capability of a Schottky diode is a novel field of research, with studies predominately reporting on the beneficial influence of wafer thinning as a way of enhancing the surge-current capability.…”