Performance of a Dual, 1200 V, 400 A, Silicon-Carbide Power MOSFET Module Damian Urciuoli damian.urciuoli@us.army.mil Ronald Green ronald.greenjr@us.army.mil Aivars Lelis aivars.j.lelis@us.army.mil Dimeji Ibitayo dimeji.ibitayo@us.army.mil U.S. Army Research Laboratory, 2800 Powder Mill Road, Adelphi, MD, 20783 USA Abstract -- A dual 1200 V, 400 A power module was built in a half-bridge configuration using 16 silicon-carbide (SiC) 0.56 cm 2 DMOSFET die and 12 SiC 0.48 cm 2 JBS diode die. The module included high temperature custom packaging and an integrated liquid cooled heat sink while conforming to the footprint and pinout of a commercial dual IGBT package. Die encapsulant was not used, to allow data collection by infrared thermal imaging. The module was DC tested at currents up to 400 A and coolant temperatures up to 100 ˚C. Switching was evaluated in a boost converter at load power levels up to 25 kW and at frequencies up to 30 kHz with coolant temperatures up to 80 ˚C. Acceptable current sharing between MOSFET die was observed over the switching frequency and coolant temperature ranges. Package thermal resistances and MOSFET and diode power losses were characterized. Results were compared to those simulated for a 400 A IGBT module. Index Terms – Power MOSFETs I. INTRODUCTION Silicon-carbide (SiC) power electronic devices offer higher temperature operation, higher breakdown voltage limits, and lower losses than their Si counterparts [1]. These features provide critical performance benefits for power electronic systems, especially those of the automotive sector where higher temperature and more compact operating environments are common. SiC based power converters have been proposed to replace Si IGBT based units and support hybrid electric drive systems with thermal management provided by engine coolant at temperatures up to 100 ˚C. Improvements in SiC device technology in recent years have enabled large area junction barrier Schottky (JBS) diode and DMOSFET (doubly-implanted MOSFET) development [2],[3]. Recently fabricated advanced research and development engineering samples of these two types of devices having total chip areas of 0.48 cm 2 and 0.56 cm 2 , respectively, were used to develop a 1200 V, 400 A dual all SiC power module in a half-bridge configuration. In previous work, 0.56 cm 2 SiC MOSFETs were co- packaged to form 100 A single switch modules. The modules were evaluated in a switching converter at rms currents up to 90 A using 60 ˚C to 90 ˚C coolant. Projected die temperatures for the tests exceeded 180 ˚C as discussed in [4]. Fig. 1 shows typical MOSFET drain current versus drain-to-source voltage curves, and Fig. 2 shows typical MOSFET ON-state resistance versus temperature. Although these relationships are typical, they can vary slightly between die. The MOSFETs were conservatively rated at 50 A each (223 W/cm 2 ) based on modeling and measured thermal resistances. 0 10 20 30 40 50 0 1 2 3 Drain Current, I D (A) Drain-Source Voltage, V DS (V) (25 ˚C) VGS=15V VGS=10V VGS=5V Fig 1. Typical SiC 0.56 cm 2 MOSFET ID vs. VDS 30 35 40 45 0 50 100 150 200 250 ON-state Resistance (mΩ) Temperature (°C) (V GS = 15 V) Fig 2. Typical SiC 0.56 cm 2 MOSFET RDS-ON vs. temperature Based on the favorable performance of the 100 A single switch modules, it was necessary to determine the feasibility of placing a greater number of die in parallel per switch. Measurement of current sharing effects for DC at die temperatures below and above that corresponding to minimums in ON-state resistance was needed. Information about the sharing of transient currents in a power switching application over a range of frequencies, and the effects of parasitic inductances introduced in packaging was also important. Finally, characterization of package thermal 3303 U.S. Government work not protected by U.S. copyright