TSUKUBA, Japan -- At a technical conference here this week, Cree Inc. disclosed development a silicon-carbide PiN power diode and SiC-based power MOSFET transistors that have 10 times the power levels of devices announced at last year's the meeting. The Durham, N.C.-based company said these scaled-up devices could soon address power conditioning applications in commercial and military systems.
"We believe that the power levels now being demonstrated are nearing the levels required for commercial products that can complement our Schottky diode product line," said John Palmour, director of advanced devices at Cree. "While more R&D is necessary to bring these devices to production, this is a demonstration of the rapid improvement taking place in both our material capability as well as in our device design and processing technology."
During the 2001 International Conference on Silicon Carbide and Related Materials in Tsukuba, Cree described a rectifier based on a 10 kV SiC PiN diode, which had an area of 9 mm2. The PiN diode has a current capability of 20 amps, and a pulsed power capability of 200 amps, Cree said.
Cree reported that the power levels from the devices were up to 2 MW pulsed, which the company said was the largest reported to date for a single SiC chip. The SiC power MOSFET device also had a large area, with the chip measuring 11 mm2. According to Cree, the power MOS field-effect transistor demonstrated a high voltage rating of 2.4 kV, with a current capability up to 10 amps. The on-resistance of the 240 kW device was less than 1/40th of an equivalent silicon MOSFET, said the company. This results in much lower conduction losses than silicon devices, Cree said.
The D&R work on high voltage rectifiers was funded in part by the Air Force Research Laboratories. The MOSFET research was funded by the U.S. Defense Advanced Research Projects Agency (Darpa) and the Office of Naval Research.