OSLO, NORWAY: SemiSouth Laboratories Inc., a leading manufacturer of silicon carbide (SiC) technology for high-power, high-efficiency, harsh-environment power management and conversion applications, has presented a paper entitled ‘Low Switching Energy 1200V Normally-Off SiC VJFET Power Modules’ at the European SiC and Related Materials Conference.
The paper presents the development of an all-SiC-based power module for use in high frequency and high efficiency applications. SemiSouth co-founder and CTO Dr. Jeffrey B. Casady, co-authored the paper with lead author and presenter, Dr. David C. Sheridan, Director of Engineering.
Dr. Casady commented: “As SiC devices migrate to applications above 20-30kW, multi-chip power modules offer the most energy-efficient and practical solution for a wide range of applications such as high-power commercial solar inverters, electric vehicle inverters and electric actuators in aircraft. However, the high speed transients capable in SiC devices at high voltages and currents highlight the need for careful design considerations for gate drive, wiring, layout, and module parasitics.”
The module described uses SemiSouth’s high speed, normally-off 1200V SiC VJFET technology, and demonstrates record low hard-switching performance (1.25mJ) in an optimized, commercially-available (SP1) module configuration. Parasitic oscillations and cross-conduction were shown to be well-controlled using optimized internal snubbers and a negative gate voltage rail.
Utilizing parallel combinations of enhancement mode SiC VJFETs (36mm²) and Schottky diodes (23mm²), a total on-resistance of only 10mΩ (2.7mΩ/cm²) was achieved at drain currents of 100A in the commercially available standard module configured as a half-bridge circuit.
Concludes Casady: “A significant percentage of the targeted customers for SiC power transistors will favor devices integrated into the module form factor presented here for higher power and complexity, saving cost and area in the overall system design.”