Reliability of Silicon Carbide MOSFETs: status and improvement prospect

Abstract: Silicon Carbide Metal-Oxide-Semiconductor Field-Effect Transistors (SiC MOSFETs) are the most disputed technology in power electronics over the last decade, as it represents a concrete candidate to take over Silicon-based traditional InsulatedGate Bipolar Transistors (IGBTs). Many hurdles still need to be overtaken, though, including primarily cost and reliability.
The tutorial presents the current status of Silicon Carbide MOSFET technology from a reliability perspective, and it is split in two parts, namely: I) Introduction and II) Current issues and case studies.
After a brief introduction about reliability basics and their implication in power electronics, Part I starts with a recapitulation of MOSFET device’s operating principle, then moves straight to the state of the art of SiC MOSFET technology, including both semiconductor and packaging. Differences with Silicon-based traditional MOSFET technologies are listed up afterwards, putting the stresses on the most challenging ones, both in terms of
design and application.
A set of detailed studies are presented in the second part, including some in-depth discussions on temperature uniformity issues at chip level, electro-thermal modeling, short-circuit capability and related predictive models, issues at packaging level, and accelerated test principles, including major challenges.
A couple of important case studies are also presented, namely: i) implication of short circuit stress on threshold voltage and ii) implication of threshold voltage instabilities on aging phenomena.
Condition monitoring principles for SiC MOSFETs conclude the second part, and present challenges in SiC MOSFETs’ reliability are presented at the end of the tutorial.
The proposed teaching style is mostly practical/application related, and aimed at beginners, both from academia and industry.

Francesco Iannuzzo received the M.Sc. degree in Electronic Engineering and the Ph.D. degree in Electronic and Information Engineering from the University of Naples, Italy, in 1997 and 2002, respectively. He is primarily specialized in power device modelling. He is currently a professor in reliable power electronics at the Aalborg University, Denmark, where he is also part of CORPE, the Center of Reliable Power Electronics. His research
interests are in the field of reliability of power devices, including mission-profile based life estimation, condition monitoring, failure modelling and testing up to MW-scale modules under extreme conditions. He is author or co-author of more than 190 publications on journals and international conferences, three book chapters and four
patents. Besides publication activity, over the past years he has been invited for several technical seminars about reliability at first conferences as ISPSD, EPE, ECCE, PCIM and APEC. Prof. Iannuzzo is a senior member of the IEEE (Reliability Society, Power Electronic Society, Industrial Electronic Society and Industry Application Society). He
currently serves as Associate Editor for Transactions on Industry Applications, and is secretary elect of IAS Power Electronic Devices and Components Committee. He was the general chair of ESREF 2018, the 29th European Symposium on Reliability of Electron devices, Failure physics and analysis, which scored +400 participants from 43
countries.