Advanced High Current and Voltage SiC Diodes for Power Switching

We propose to design, fabricate and develop an advanced SiC diode that can lead to (i) substantially reduced volume and weight of power systems, (ii) greatly expanded operating temperature range, and (iii) drastically improved power efficiency and enhanced radiation tolerance. We propose to compare and optimize different designs of the proposed SiC power diodes. We propose to fully develop the critical processing technology to fabricate optimum performing devices. In comparison to the excellent results achieved in Phase I, we propose to further reduce the reverse leakage current density by 1000X, increase the forward current density by 100%, and increase the diode cell size by 10X. Multiple batches of the diodes will be fabricated to systematically improve the device performance with increasing power level. The final target is to achieve power level up to 500kW. Systematic characterization and mapping will be done and operation into avalanche mode will be use to qualify the edge termination technology. We propose to dice and package the diodes suitable for up to 250C operations. Half-bridge inverter testing will be done to determine the AC characteristics and the diode stress handling capability. Reliability issue will be investigated and approaches to improve device lifetime will be identified.