Development of High Power IGBTs for High Level RF Accelerator Systems

Insulated Gate Bipolar Transistor (IGBT) technology, which combines the characteristics of both MOS and bipolar structures, is highly advantageous for power systems, which includes high input impedance allowing small gate drivers, short circuit withstand capability and robust turn-off performance. Higher power IGBTs with voltage greater than 6 kV and current larger than 2 kA is highly desired for development of high power modulators and power supplies. For the past decade the advancement of IGBT technology has been mainly based on the soft punch through (SPT) and field stop (FS) buffer concepts for thin silicon wafers, especially for power devices below 2 kV because their ability to achieve very low power losses for a given voltage class. However, SPT/FS buffer concepts are more and more approaching the design limits. Continuous advancement of the IGBT technology calls for more efficient buffer concepts for further power loss reductions while retaining good overall performance. In this DOE SBIR effort, Global Nanosystems proposes a novel concept that combines with a field control-punchthrough (FCPT) structure for collector, an enhanced-trench-gate cell for emitter, and a proprietary equal potential- line design for termination. Apparently, the overall objective of the effort is to explore the feasibility of the proposed concept to the development of high power IGBTs for high power modulators and supplies. In Phase I, we will at first perform thorough simulations and designs of various high power IGBT devices that implement with our proposed concept followed by their integration, fabrication and characterization. In Phase II, high power IGBT modulators for applications specifically in solar energy power stations will be designed, fabricated and characterized by working with our partners and semiconductor foundries. Commercial Applications and other Benefits as described by the awardee: Successful development of high power IGBT modulators means various high power IGBTs for various high power and energy saving applications can be designed and fabricated. We see that the commercialization potential will be tremendous and revolutionary for the semiconductor high power and energy saving industries. Furthermore, the project will be integrated with the UCLA undergraduate microfabrication education and research experiences program. Two undergraduates will be supported under the projec