Alberto Castellazzi
Solid-State power Processing (SP2) Lab Faculty of Engineering Kyoto University of Advanced Science
Topic: Unleashing the full WBG potential: a joint topology-technology development effort
Alberto Castellazzi is a Professor in the KUAS Mechanical and Electrical Systems Engineering Department, where he leads research and teaching in advanced solid-state power processing, including the characterization and use of wide-band-gap (WBG) semiconductor devices (silicon carbide, SiC; gallium nitride, GaN), their packaging and thermal management.
He holds a Laurea degree in Physics from the University of Milan, Italy, 1998, and a PhD degree in Electrical Engineering from the Munich University of Technology (TU Munich), Germany, 2004, and has been involved in power electronics research and development for over 20 years, with affiliation and working experience both in industry and academia, including SIEMENS Corporate Technology (Germany), ETH Zurich (Switzerland), ALSTOM Transport (France) and The University of Nottingham (UK).
Alberto has published over 250 papers in specialist international journals and conference proceedings and has held a number of invited talks, tutorials and seminars on the topic of WBG power devices and SiC-based electrical power conversion. He is active as both a reviewer and editor and is a member of the technical program committee of a number of international conferences on power electronics and power semiconductor devices.
He is a member of The Power Electronic Conversion Technology Annex (PECTA) of the International Energy Agency (IEA)
Semiconductor power devices are key in determining the performance of modern power converters. The introduction of wide-band-gap (WBG) technology yielded disruptive potential for progress in the joint improvement of efficiency, power density and reliability. However, unleashing its full potential and justifying its higher cost in large volume applications still requires the deployment of bespoke technological and topological solutions. This tutorial reviews the understanding generated so far and discusses pathways for future developments.
Leo Lorenz
European Center for Power Electronics (ECPE)
Topic: New Generation of Power Semiconductor Devices - Challenges in Reliability and Application
Leo Lorenz was born in Haibach, Germany, in 1946. He received the Dipl.-Ing. degree from the Technical University of Berlin, Berlin, Germany, in 1976 and the Dr.-Ing. degree from the University of Munich, Germany, in 1984. From 1976 to 1980, he was with AEG, R&D –Center for Power Electronics, Berlin. In 1984, he joined Siemens Semiconductor Division which became Infineon Technologies AG, Munich, Germany, in 1999. Since then he has worked on power semiconductor and power ICs in different functions and responsibilities. He has published over 500 technical papers in these fields. In 2001, he became a Professor for system integration at the University of Ilmenau, Ilmenau, Germany. Dr. Lorenz is President of the ECPE (European Center of Power Electronics).
Power electronics is a cross-sectional and ubiquitous field as it covers many disciplines, including material science, semiconductor physics and power devices, assembly and interconnection technologies, electrical circuit topologies, and control, in all systems and applications dealing with electric energy from the Milliwatt range up to Gigawatt power.
The miniaturization of converter systems and increased power density, enabled by modern wide bandgap power semiconductor devices, lead to significant materials savings, e.g., on copper and aluminum. Further innovations are needed in life-cycle assessment especially in CO2 Footprint and circular economy with a focus on reuse and recycling in power electronics.
Finally, the importance of reliability and availability should be mentioned as reliability is a key differentiator for Europe´s power electronics industry. Reliability is a cross-sectional and multidisciplinary topic starting from the material science behind the degradation mechanisms, covering technology and product qualification and testing, and addressing also intelligent reliability concepts including condition and health monitoring.
The reliability and ruggedness of these new power semiconductors is driven by an advanced chip design and new interfacing and packaging technology. For ultra-high efficiency and ultra-high power density system solutions WB-devices are being developed. However, it must be considered that the application engineer is faced with new challenges of how to manage all the parasitic, the thermal management and the circuit design.
In the presentation the development trend of some examples in power converters and Power Devices will be shown and the challenges in packaging technologies and system application will be discussed. Driven by the working groups organized in ECPE several key reliability requirements in the E-Car (AQG 324) and Railway applications will be shown and discussed. Also, one example of Life Cycle analysis in terms of CO2 footprint will be shown.
Wataru Saito
Kyushu University
Topic: Avalanche breakdown behavior and robustness of SiC and GaN transistors
Wataru Saito received the B.Eng., M.Eng., and Dr.Eng. degrees in electrical and electronics engineering from the Tokyo Institute of Technology, Tokyo, Japan, in 1994, 1996, and 1999, respectively.
In 1999, he joined the Toshiba Corporation, Kawasaki, Japan, where he engaged in the development of power semiconductor devices. Since 2019, he has been with Kyushu University, Fukuoka, Japan. His current research interests include basic research on next-generation power semiconductor devices and related application technologies.
He is an editor of IEEE Transactions on Electron Devices. He formerly served on the committee member of Power Devices & ICs Committee in IEEE Electron Device Society from 2015 to 2020. He is a member of the technical program committee of IEEE Electron Devices Technology and Manufacturing Conference. He formerly served on the technical program committees of IEEE International Electron Devices Meeting from 2020 to 2021 and IEEE International Symposium on Power Semiconductor Devices and ICs from 2016 to 2020. He received the conference prize paper award in 2008 IEEE Power Electronics Specialists Conference.
SiC and GaN power transistors offer high switching speed, low on-resistance and much better FOM when compared to silicon power MOSFETs. From viewpoint of safe operation for power electronics application systems, SiC and GaN transistors have been evaluated in reliability test as same method as conventional Si power devices. There are many reports focusing on unique points of SiC and GaN transistor failure modes due to material difference. This talk will provide a review on avalanche breakdown behavior and failure mode of SiC and GaN transistors. The avalanche robustness and its impact on the application circuits will be also presented.
