Dr. Martin Rittner - Robert Bosch GmbH

Automotive Power Module Qualification Guideline AQG324

– Now with ‘SiC-Inside’; and GaN Is on Its Way Ahead

Speaker Biography

Dr. Martin Rittner is senior expert for power electronics assembly and interconnection technologies in the Corporate Research unit of Bosch. He studied Physics at the University of Stuttgart/Germany and received his diploma in Nuclear Physics in 1994. Afterwards he conducted his PhD thesis in the field of Semiconductor Physics at same university. Since working as research employee in the Corporate Research sector of Bosch in 2001, he attended several German and EU public funded projects in the field of electronics packaging and assembly technologies for automotive and power electronics applications. For the German automotive supplier industry, he is currently the chairman of the joint ZVEI-ECPE working group ‘High Temperature and Power Electronics’, and additionally he is the chairman of the ECPE working group ‘Automotive Power Module Qualification Guideline (AQG324)’. In the year 2015, he rounded his academic skills by finalizing his economic studies and receiving the degree as Master of Business Administrations (MBA).

Abstract

The evolutionary history, recent work and results of the industry experts’ working group founded within the ECPE are illustrated. In this so-called AQG 324 ‘Automotive Power Module Qualification Guideline’ working group, qualification routines for power modules are under expert discussions and investigations for their later usage in automotive vehicles. Considerations take place, which existing routines are incomplete or which ones are missed from the perspective of automotive requirements and what has to be implemented newly to assure automotive high-level reliability and robustness demands.

Since the release of guideline version 3 in May 2021, the new SiC-appendix in the document now respects and describes the qualification requirements on SiC-based power modules in automotive drive inverter applications. Especially the needed adjustments for performing valid power cycle test routines and the extension of several well-established qualification routines to their ‘dynamic varieties’ are worth to highlight. Although the descriptions of the SiC-appendix are under further fine-tuning and discussion for the upcoming document release, the ECPE working group now picks up additionally topics and tasks for GaN-based power modules. The demand on suitable and specific qualification routines – according to SiC – is identified meanwhile as urgent.

Paolo Bargiacchi (Senior Product Manager, Electrification) -

McLaren Applied

High Performance 800V Silicon Carbide Inverters for Automotive Applications: The Next Step in Electrification?

Speaker Biography

Paolo Bargiacchi received his Master’s in Mechanical Engineering from the University of Sheffield, before joining Jaguar Land Rover to work on powertrain research and development. Following on from powertrain R&D, he progressed to the propulsion planning division, defining the powertrain requirements for the next generation of JLR’s vehicles and their transition to electrification. He has since worked in various roles defining future whole-vehicle products for JLR and Bentley Motors. He is now responsible for the development of electrification products at McLaren Applied, where he is helping deliver the next step in electrification; empowering customers to introduce new vehicle concepts and technologies that drive differentiation in the market.

Abstract

With the automotive electric vehicle market rapidly maturing, OEMs are increasingly focusing their attention on integration and optimisation at a system level. In parallel, legislation is already developing past the basic requirement for zero tailpipe emissions and starting to introduce efficiency measures to determine the taxation of electric vehicles. The advancements being made in power electronics technology meet these requirements as an enabler for a variety of wider downstream powertrain system benefits. Migrating from Silicon IGBTs to Silicon Carbide MOSFETs results in higher efficiency and faster switching speeds, which in turn mean the battery, electric motor and cooling systems can all be optimised. 800V SiC inverters lead to vehicles with faster charging, higher efficiency and longer range – the next step in electrification.

Dr Jun Zeng, Co-Founder and CTO - MaxPower Semiconductor

SiC MOSFETs Manufacturing: key process aspects and supply chain challenges

Speaker Biography

Dr Jun Zeng started his professional career in power semiconductor field in 1989. Since then, he has worked in many aspects of power semiconductor technology and product development, especially in Si and SiC planar and trench MOSFETs, IGBTs and Rectifiers, etc. He has gained a rich experiences from production definition, device design, fabrication process development, and TCAD modeling/simulation to the test and reliability assessment. Notably, in his over 25 years industrial experiences, he has worked with more than dozen power semiconductor fabs and accumulated a broader experience and know-how in manufacturing process development of various Si and SiC based power semiconductor devices for enhancing product performance and reliability as well as reducing manufacturing cost. He is co-inventor of more than 100 issued and pending patents.

Abstract

Thanks to the superior properties of silicon carbide (SiC) material, it has attracted a great deal of attention from semiconductor academics and industry for decades. As well known, power MOSFETs based on SiC material are highly desired to be used as a power control/handling component in high performance switching power application because of their ability achieving lower on-resistance, reduced switching losses, faster switching speed and higher operation temperature. Currently, majority technical issues of 4H-SiC MOSFET have been either resolved or improved for realizing its commercialization with excellent and reliable electro-thermal characteristics obtained. However, in order to reach and retain its excellent characteristics in high-volume production as its silicon counterpart ( such as Si MOSFET/IGBT) has achieved, the starting material related, fabrication process related and design related challenges are still faced and are demanded to be continuously improved. In power semiconductor industry, the device design and its fabrication process is strongly coupled to each other, and they must work together very closely in order to develop a high performance and cost-efficient product. The fabrication process is a key part of a power semiconductor product. In this talk, these challenges in fabrication of 4H-SiC power MOSFET and its supply chain management, including the self-aligned channel, the gate oxidation/post-oxidation anneal (POA), high temperature implant/post-implant anneal (PIA), trench etch/post-etch anneal (PEA), metallization and wafer dicing as well as the starting material defect control, will be reviewed and discussed.

Professor Martin Kuball, University of Bristol

GaN power devices – Do we understand how they work?

Speaker Biography

Professor Kuball is Royal Academy of Engineering Chair in Emerging Technologies at the University of Bristol, and Director of the Centre for Device Thermography and Reliability focusing on wide and ultrawide bandgap semiconductors including for power electronic applications. He is Fellow of IEEE, SPIE, MRS, IET and IoP, and obtained his PhD from the Max Planck Institute for Solid State Physics, Stuttgart, Germany and joined the University of Bristol after being Feodor Lynen Postdoctoral Fellow at Brown University where he was involved in the first demonstration of US made blue laser diodes

Abstract

Gallium Nitride (GaN) has become of major importance for power electronics in the mid-voltage range, with an increasing number of products ranging from laptop chargers, electric vehicles to other applications. GaN is though a very unusual material in that its works for power and many other devices despite it being full of defects, ranging from point defects to dislocations. Devices actually work because of these defects which is quite surprising. In this talk I will review the operation of GaN power electronic devices, limitations, and opportunities, and why they work

Dr Donald A. Gajewski, Wolfspeed Inc.

SiC Device Reliability for Power Electronic Conversion Applications

Speaker Biography

Dr. Donald A. Gajewski is the Director of the Reliability Engineering & Failure Analysis Department for Wolfspeed, Inc., covering GaN-on-SiC HEMT-MMICs for RF and microwave applications, SiC power MOSFETs, SiC Schottky power diodes, and SiC power modules. He has been in the semiconductor industry reliability profession for 21 years, with previous tenures at Nitronex, Freescale and Motorola. He has experience with other semiconductor technologies including highly integrated silicon CMOS including SiGe HBT and SmartMOS; magnetoresistive random access memory (MRAM); and advanced packaging including flip-chip and redistributed chip package (RCP). He completed a National Research Council Postdoctoral Research Fellowship at the National Institute of Standards and Technology, in the Semiconductor Electronics Division, in Gaithersburg, MD. He earned the Ph.D. in physics from the University of California, San Diego, partially under the auspices of a National Science Foundation Fellowship.

Abstract

SiC devices offer performance advantages over Si devices for power electronic conversion applications, due to their wide bandgap and other key materials properties. For example, SiC can more easily be used to fabricate MOSFETs with very high voltage ratings (up to 10 kV), and with lower switching losses. The reliability of SiC power devices is excellent and has continued to improve due to continuing advancements in the quality of SiC substrates and epitaxy, as well as maturation and improvement of wafer fabrication. This has enabled the rapidly accelerating adoption of SiC devices, particularly for power electronic conversion applications such as electrified vehicle traction and charging, solar energy and power supplies. In this talk, I will review the wear-out mechanisms and intrinsic reliability performance of today’s state-of-the-art commercially available devices, the mission profiles and harsh conditions that are being demanded by applications of interest, and the current state of industry consortia reliability and qualification guidelines and standards that will help assure minimum required quality and reliability.