BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Memento EPFL// BEGIN:VEVENT SUMMARY:Pushing the limits of high power devices with wide band gap materi als DTSTART:20140129T150000 DTSTAMP:20260501T141617Z UID:609ef6ce7915211dfaff9dbbd83d58c6e25ac8ecedfb0be4d4e420a6 CATEGORIES:Conferences - Seminars DESCRIPTION:Dr. Farid Medjdoub\, IEMN\, Lille\nBio: Farid Medjdoub is a CN RS senior scientist at IEMN in France. He is affiliated with the Departmen t of Circuit and System. He received his MS and PhD degrees in Electrical Engineering from the University of Lille in France in 2001 and 2004\, resp ectively. In 2005\, Farid Medjdoub joined the University of Ulm in Germany as a Research Associate. There\, he was leading a successful European pro ject targeting the development of new transistors based on a novel InAlN/G aN heterostructure paving the way for high power applications at millimete r wave frequencies. Following this work this heterostructure has been adop ted worldwide. In 2008\, he joined IMEC\, a world-leading research center in nano-electronics and nano-technology as a senior scientist on GaN power devices. He developed innovative normally-off (In)AlN/GaN power transisto rs for high voltage applications and was leading the effort on reliability assessment of state-of-the-art L-band GaN-on-Si devices within a European project. Then\, in 2010 he has been recruited by the National French Rese arch Center (CNRS) in France and continued his effort on GaN devices as se en from the state-the-of-art devices achieved recently.\nFarid Medjdoub´s research interests include the design\, processing and characterization o f new electronic devices based on wide band gap semiconductors for millime ter-wave power amplification and low noise applications as well as for hig h power conversion. He is particularly interested in the development of ne w concepts based on the unique properties of nitrides semiconductors. He i s author or co-author of more than 100 scientific papers in international journals and conferences\, three book chapters\, multiple invited talks an d 4 patents. He is a regular reviewer for IEEE journals and expert member of the French Micro- and Nanotechnology observatory. He is also a TPC memb er of the novel IEEE international conference Wide Band Gap Power Devices and Applications (WIPDA) held yearly in the US.\nWide band gap (WBG) semic onductors enable devices to operate at much higher temperatures\, voltages \, and frequencies making the power electronic modules using these materia ls significantly more powerful and energy efficient than those made from c onventional semiconductor materials. Thus\, WBG devices are expected to pa ve the way for exciting innovations in both RF and power electronics.\nIn particular\, Gallium Nitride (GaN) devices are foreseen as the next genera tion of RF power transistor in the millimeter wave range. In this frame\, we developed an innovative technology based on AlN/GaN/AlGaN double hetero structure grown on silicon substrate. The aim is to realize robust and cos t-effective circuits in the Ka band and beyond that would pave the way to a European source of reliable millimeter wave MMIC GaN-on-Silicon circuit telecommunication and radar systems.\nFurthermore\, as an alternative to S ilicon devices\, GaN power switching devices are emerging as an attractive candidate to support the next generation of full electric vehicles as wel l as to renewable energy systems. Indeed\, a power switching device is one of the key components that determines the performance of such systems. Pr esently\, Silicon insulated gate bipolar transistors (Si-IGBTs) are typica lly used in the converters and inverters. However\, Si devices have attain ed technological maturity and have a limitation of performances due to the ir material limits. They have high on-resistance leading to large conducti on losses\, low switching frequency meaning larger capacitors and inductor s are required for filtering and they cease to function beyond 150°C and so require cooling. Next generation of power switch devices need to be mor e efficient\, lighter and deliver high power (> 100kW) with high power sou rce voltage (> 600V) for increased driving range. This can be addressed by using GaN material grown on Silicon owing to its intrinsic properties. Ho wever\, there are still challenges to be overcome for 600 V GaN devices be fore commercialization such as the dynamic on-resistance degradation which involves the control of the passivation\, the gate dielectric deposition\ , the growth and processing quality etc. Normally-off GaN device operation is also required while this type of device operates inherently in normall y-on (i.e. negative threshold voltage) conditions. We are developing sever al solutions to overcome this issue. Finally\, in longer term\, power elec tronic applications around 1 kilovolt could also be impacted by the emergi ng GaN-on-Si devices. Today\, the breakdown voltage (VBK) of these devices is limited to around 1.5 kilovolts. We have determined that the main limi tation of VBK was the silicon substrate as the electric field crosses the entire GaN heterostructure that has a total thickness limited by strain is sues. We are developing a disruptive technology that should significantly enhance the VBK of GaN-on-Si devices beyond 3 kilovolts based on the local silicon substrate removal.\nIn this talk\, I will describe the origin\, t he history and the prospect of this specific GaN technology that could cre ate a real breakthrough for power electronic applications from DC up to th e millimeter wave range. LOCATION:ME B1 B10 http://plan.epfl.ch/?lang=en&room=MEB1B10 STATUS:CONFIRMED END:VEVENT END:VCALENDAR