Technical Insight
Cree's first SiC Schottky diodes (Nitride News)
Cree has begun shipping sample volumes of its first SiC Schottky diode chips. These will find application in high power circuits such as high frequency power supplies and motor controls. Typically, 50% of the power loss in a silicon PIN diode-based circuit arises because of the slow switching speed of the diode. SiC is able to operate at much higher speeds, virtually eliminating this source of power loss. It is expected that this will give an overall reduction in power consumption of between 4 and 7%, allowing smaller device sizes and reduced heat sink areas. Initially two device types are being sampled, a 600 V, 1 A device and a 600 V, 4 A device. Cree are expecting to ramp up production during the first quarter of fiscal 2002, with additional products to be added over the next year. In further news, a joint program with Kansai Electric Power Company has yielded record results for several high-power devices. A 6 kV MOSFET and a 5.5 kV JFET had on-resistances that were only 1/25 and 1/65, respectively, of the theoretical limit for the equivalent silicon devices. High voltage SiC PIN diodes have also been demonstrated with blocking voltages up to 19 kV, 50% over the previous record and double that from commercially available silicon devices.
