Silicon carbide Schottky diodes

Award Year 

Dr. James Scofield, of the Air Force Re-search Laboratory Propulsion Director-ate (AFRL/PRPE) championed a novel plasma processing technique for fabri-cating power electronic devices based on the robust semiconductor material, silicon carbide (SiC). This SiC Schottky diode technology is a high-speed switching device, which pre-viously relied on silicon (Si) technology. This specialized semiconductor device is proven to reduce energy losses from conduction and switching, and for faster switching characteristics in high-speed electronic circuit applications. SiC (more) de-vices are superior to silicon in virtually every respect.The SiC Schottky diode is now available in the 300-1200 volt class, enabling the use of its high switching speeds to yield dramatically increased power system efficiency. High voltage power products that previously could not take advantage of the attractive characteristics of a Si Schottky device, can now utilize the SiC Schottky diode. SiC technology enables downscaling of the size and weight of power components. Dr. Scofield transferred this technology in collaboration with Mississippi State University to incubate SemiSouth Labo-ratories, under funding from the Ballis-tic Missile Defense Organization (now known as the Missile Defense Agency). He also implemented a Dual Use Sci-ence and Technology agreement with manufacturer Cree, Inc., of Durham, North Carolina. Cree has successfully commercialized the first SiC power de-vice (SiC Schottky diode), and this has led to the first commercially available SiC field effect power transistor offered by a U.S. company. After commercializing the SiC Schottky diode, Dr. Scofield forged an effort to develop and mature a switching tran-sistor device to complement the diode. SiC was promoted and formulated into a program to develop a junction field ef-fect transistor (JFET) integrating the SiC Contact: Dr. James Scofield, (937) 255-5949, diode. As a result, Semi-south Laborato-ries released a line of 600-volt power JFET/Schottky di-odes in a single package in spring 2004. The com-mercial name for this technology is Harsh Environ-ment Low Loss Field Effect Transistor (HEL2FET™). The SiC is now used in electronic power supplies, motor drives, and power con-version equipment throughout the world. The commercial and industrial applica-tions for the SiC JFET and Schottky di-ode are vast, and will have a tremendous impact on reducing electrical energy consumption for lighting and consumer/industrial electronics, thus substantially reducing dependency on foreign oil. (less)