Keynote Sessions

Title: Advances in GaN Power ICs: Efficiency, Reliability & Autonomy

Abstract: GaNFast™ power ICs, use next-generation gallium nitride (GaN) to replace legacy silicon chips to enable up to 3x faster charging and 3x more power in half the size and weight for mobile fast chargers, consumer electronics, solar, data centers and EVs, replacing silicon in a market worth over $13B by 2026.

Now, a next-generation enables even higher efficiency, autonomy and reliability with precision sensing of system current, voltage and temperature and real-time control and protection. External monitoring components – such as large, lossy sense resistors – are eliminated, reducing system power loss, reducing complexity and reducing cost.

This new GaNFast generation is a core element as we “Electrify Our World™” and accelerate the conversion away from fossil fuel sources and loads. As well as enabling efficiency improvements that reduce the carbon emissions of target applications, small die-size, fewer manufacturing process steps and integrated functionality mean that GaNFast power ICs have up to 10x lower CO2 footprint than silicon-based solutions, and save 4 kg CO2 per IC shipped, vs. equivalent legacy silicon chips.

Dan Kinzer is COO, CTO, Co-founder and Director of Navitas Semiconductor, a young company focused on advanced GaN power semiconductor devices and circuits. For over 30 years, Dan has led R&D at leading power semiconductor companies at the VP level or higher. His experience includes developing advanced power device and IC platforms, wide bandgap GaN and SiC device design, IC and power device fabrication processes, advanced IC design, semiconductor package development and assembly processes, and design of electronic systems. Before Co-founding Navitas, Dan served 7 years as SVP & CTO at Fairchild Semiconductor. Before that he served 28 years at International Rectifier in various roles including VP R&D and Chief Technologist. He has a BSE degree in Engineering Physics from Princeton University.

 


Title: One Size Doesn’t Fit All – The Need for Multiple Approaches to GaN Circuit Design

Abstract: Power design engineers want simplicity and the maximum degrees of freedom in making choices for the design challenges they face every day. They don’t want transistor suppliers to predefine the operation of a circuit in ways that may limit their approach to maximizing performance. Power designers want to innovate, optimize and not be constrained. There will always be a need for a mix of discrete, multi-chip packages, and power module form factors in order to meet the growing number and variety of GaN applications.

Jim Witham’s career has focused on bringing new technology, like GaN Systems’ world’s best performing power transistors, to the Electronics market.

Witham joined GaN Systems from Neoconix, a manufacturer of high density, miniature connectors. As CEO of Neoconix, he successfully implemented strategic changes which dramatically increased revenue and resulted in the company’s acquisition by Unimicron Technology. Prior to Neoconix, Witham was CEO of Fultec Semiconductor, where his team made circuit protection devices using high voltage silicon, silicon carbide and gallium nitride (GaN) transistors. Fultec was acquired by circuit protection market leader Bourns. Witham has also held VP Sales & Marketing positions at Aegis Semiconductor, a tunable filter semiconductor manufacturer and Genoa, a semiconductor optical amplifier manufacturer.

Other notable career highlights include senior executive positions at Raychem, including General Manager of the Raychem Interconnect Division and Director of Asia Sales & Marketing, based in Japan, for the Raychem Circuit Protection Division. As an Engineering Specialist at General Dynamics’ Space System Division during the eighties, Witham designed fluid systems for the Space Shuttle and was on Mission Control for interplanetary missions. Witham holds an MBA from Harvard and both M.S. and B.S. with distinction in Mechanical Engineering from Stanford.


Title: SiC MOSFETs and the Drive for Electric Vehicles

Abstract: SiC semiconductor technology has enjoyed rapid market adoption in the last few years.  SiC MOSFETs have been adopted in a variety of markets such as solar inverters, industrial power supplies, and EV on-board and off-board chargers.  But the rapid adoption of SiC for the drive train inverters in Battery Electric Vehicles is changing the market landscape for SiC.  It is being adopted in these inverters because it offers a 5-10% improvement in efficiency, which results in either extended range for the vehicle for a given battery charge, or a reduction in the battery pack required to go a certain distance.  A large number of automotive OEMs now have SiC targeted for incorporation into their EV drives.

SiC power device manufacturing is based now on 150 mm substrates, allowing cost  reduction over recent years. As the market grows further, the push to 200 mm substrates is inevitable, and Cree | Wolfspeed’s new wafer fab will be the first to start production on 200 mm.

Dr. John W. Palmour is the Chief Technology Officer for Wolfspeed, a Cree company.  He focuses on SiC power devices, GaN microwave device, and WBG materials development for Wolfspeed.  He was one of the co-founders of Cree in 1987, and served on the Board of Directors for the company from 1995 to 2010.  Dr. Palmour has been a leader in SiC and GaN device development for the last 32 years, and has demonstrated numerous firsts in these technology areas.  He has been responsible for the development of high voltage, 4H-SiC power transistors and diodes, as well as high frequency GaN HEMTs and MMICs.  During his career, he has authored or co-authored more than 380 publications and is a co-inventor on 75 U.S. patents.  Dr. Palmour received his B.S. and Ph.D. degrees from North Carolina State University, Raleigh, in 1982 and 1988, respectively, where his major was in Materials Science and Engineering.  Dr. Palmour became a Fellow of the IEEE in 2013.


Title: Gallium Nitride Integration and the End of Discretes

Abstract: Integrated circuits made using GaN-on-Si substrates have been in production for over seven years.  During  that time, GaN-based ICs have evolved  from pure discrete devices to monolithic half-bridge devices and then onto  power FETs that included their own monolithically integrated driver, and more recently, to fully monolithic power stages including power FETs, drivers, level shifting circuits, logic, and protection. In this talk we will look at the roadmap of GaN-on-Si integration and show how the role of discrete transistors is destined to diminish to near-zero in the next few years.

Alex Lidow is CEO and co-founder of Efficient Power Conversion Corporation (EPC).   Since 1977, Dr. Lidow has been dedicated to making power conversion more efficient upon the belief that this will reduce the harm to our environment and increase the global standard of living. Dr. Lidow served as CEO of International Rectifier for 12 years prior to founding EPC in 2007.  Dr. Lidow holds many patents in power semiconductor technology, including basic patents in power MOSFETs as well as in GaN transistors and integrated circuits.  He has authored numerous peer reviewed publications on related subjects, and recently co-authored the third edition of the seminar textbook on GaN transistors, “GaN Transistors for Efficient Power Conversion,” published by John Wiley and Sons. Dr. Lidow earned his PhD in Applied Physics from Stanford in 1977.


Title: Smart Gate Driver ICs for GaN Power Transistors

Abstract: GaN power HEMTs are known to offer high switching speed, low on-resistance and much better FOM when compared to their silicon counterparts. However, the ability to operate with high power density in a smaller form factor presents new challenges for reliable and robust operation. Traditional gate driver designs for silicon-based power devices are catered to lower frequencies with large tolerance on the gate voltage swing. They do not adequately address some of the reliability issues that are unique to GaN power transistors. This talk will provide a quick review on the gate driving requirements and limitations for GaN power HEMTs. This is followed by a survey of novel smart gate driving techniques that can further exploit the performance and enhance the reliability of GaN power devices. Topics to be covered include intelligent gate driving schemes such as active gate driving, dead time optimization, and current balancing. Emphasis will be given to designs that can be integrated and those that can monitor the devices for optimum performance and safe operation. Protection features such as short-circuit detection, gate overvoltage prevention, temperature monitoring and compensation will also be discussed. Monolithic integration of power GaN ICs is an exciting area of development with increasingly sophisticated designs reported in recent years. Fully integrated GaN building blocks and state of the art designs will be addressed.

Prof. Wai Tung Ng is a professor with the Edward S. Rogers Sr. Dept. of Electrical and Computer Engineering from the University of Toronto. He is also the director for the Toronto Nanofabrication Center (TNFC), and open access research facility. Prof. Ng is a recognized researcher in the areas of power semiconductor devices and smart power integrated circuits. His research group has demonstrated many world-first innovative designs, including a digitally reconfigurable DC-DC power converter with resizable output stage [ISPSD 2006], a superjunction power FinFET [IEDM 2010], and a series of smart gate driver integrated circuits for Insulated Gate Bipolar Transistors (IGBTs) and Gallium Nitride (GaN) power transistors. Currently, Prof. Ng’s group is actively engaged in the promotion of digitally reconfigurable gate driver circuits to improve the switching characteristics of GaN and Silicon Carbide (SiC) power transistors. These include many novel features such as one-step dead-time correction, indirect current sensing, dynamic driving strength to suppress Electromagnetic Interference (EMI), liquid-cooled packaging for intelligent power modules (IPMs), etc.

Prof. Ng earned his bachelor, master and doctoral degrees in Electrical Engineering from the University of Toronto, in 1983, 1985 and 1990, respectively.


Title: High-Frequency GaN-Based Transistor Technologies: Progress and Future

Abstract: Gallium nitride (GaN), one of the wide-bandgap compound semiconductors, has unique material properties such as high electron saturation velocity and high breakdown field. A two-dimensional electron gas (2DEG) formed at an AlGaN/GaN heterointerface via spontaneous and piezoelectric polarization effects exhibits high sheet density and high electron mobility. Using these features, transistors with various device topologies (lateral and vertical) have been developed for both RF and power electronics applications. Among them, AlGaN/GaN-HEMTs fabricated on a high thermal conductivity SiC substrate are most widely used in high-power RF amplifiers for radars, satellite communications, cell phone base stations, etc.

Owing to the rapidly increasing demand for higher bandwidths in the next generation communication and higher resolution imaging systems, millimeter-waves (30 – 300 GHz) are expected to play a critical role. Accordingly, GaN-based power amplifiers that have a high gain, output power, efficiency, and linearity at millimeter-wave frequencies are required. The frequency performance of GaN-HEMTs has been successfully improved through aggressive device scaling, and the cutoff frequency (fT) of highly scaled GaN HEMTs reached a 450-GHz range, i.e., 3-4× higher than conventional devices.

The high-frequency device scaling, however, comes at the expense of reduced transistor’s power density due to the limited voltage swing. To overcome a well-known performance trade-off of millimeter-wave transistors among operational frequency, power density, efficiency, linearity, and reliability, new III-N material platforms as well as novel transistor architectures were proposed. They include (1) new III-N barrier materials such as AlN, InAl(Ga)N, ScAlN utilizing a larger polarization effect, (2) an Al composition graded AlGaN channel, (3) N-polar GaN-HEMTs, and (4) multiple 2DEG channels with a lateral gate. In this talk, I will discuss the progress of GaN-based high-frequency transistor development and technical challenges and introduce our new approaches on multiple 2DEG channel HEMTs with a buried dual gate (BRIDGE HEMTs).

Keisuke Shinohara is a Principal Scientist with Teledyne Scientific & Imaging. He has over 25 years of experience on compound semiconductor material growth and device development. His work has focused on RF transistors and diodes based on GaN and InP material systems for high-frequency applications. He has lead government-funded R&D programs to develop deeply-scaled GaN HEMTs (DARPA NEXT), low-Ron & high-voltage GaN HEMTs for high-speed and efficient buck converters (DARPA MPC), GaN-based multi-channel transistors for linear and efficient millimeter-wave power amplifiers (DARPA DREaM), and broadband high-power amplifier MMICs based on the new GaN transistor technology (ONR EWT). He has authored or co-authored more than 120 peer reviewed journals and international conference papers including 32 invited presentations and 3 book chapters. He holds 24 patents in this technical field. Dr. Shinohara received his B.S., M.S., and Ph.D. degrees from Osaka University, Japan, in 1994, 1996 and 1998, respectively, where his major was in Engineering Science.


Title: Reliable and High Performance HV GaN in production – from Adapters to Automotive.

Abstract: The adoption of high voltage GaN on Silicon power devices is accelerating at a rapid pace over the last several years. The key for designers and system insertion has been robust and reliable, easy to interface and design, high performance normally off GaN compatible with multiple controller and driver architectures. With complete control of the core GaN materials and wafer technology as well as manufacturing, Transphorm’s high speed-high efficiency-easy to use SuperGaN FET with a proven field reliability (FIT < 0.4) products provide superior solutions for applications ranging from 30 Watts to 10 kiloWatts, today and already shipping in volume. This talk will review the growing use of GaN in markets like Fast chargers/adapters (lower power) to server, gaming, crypto mining, industrial (mid-high power) to renewables, energy and electric vehicles (high power), targeting 200% year over year growth.

Dr. Primit Parikh is the Co-founder, President & COO of Transphorm Inc.  a world-wide leader in Power Conversion with Gallium Nitride (GaN) Semiconductors that enables highly compact, efficient and cost-effective converters & inverters for markets ranging from consumer adapters, server/storage/networking power supplies to industrial applications to electric vehicles.  Primit is passionate about the intersection of business and technology, with over 20 years of semiconductor & entrepreneurial experience, his background includes Capital raises, International Markets & Strategic Partnerships, Products & Manufacturing, Intellectual Property, Gallium Nitride/Semiconductor Technology and Government Contracting.   Prior to co-founding Transphorm, Primit led GaN electronics at start-up Nitres Inc. through its successful exit via acquisition by Cree Inc. (2000), where he was responsible for RF/Microwave electronics and cross functional programs in LED technology at Cree Santa Barbara. He has co-authored more than 75 publications including industry overview articles, trade & technical papers, is a holder of more than 40 patents and received the Entrepreneur of the year award in Goleta in 2011. Primit received his B. Tech degree in Electrical Engineering from IIT Mumbai in 1993, and Ph.D. in Electrical & Computer Engineering from UC Santa Barbara in 1998.


Title: On the benefits of SiC and GaN in high power applications

Abstract: With unrivalled better technology-specific figure-of-merits SiC MOSFETs and GaN HEMTs have started to conquer high power applications such as Mobile phone chargers, On-board chargers and Motor drives replacing IGBTs or Superjunction devices.

Driven by ever higher demands on power density and efficiency and new trends such as bidirectional power flow for vehicle-to-x applications, wide bandgap power devices have turned into a focal point of design activities.

In all of these applications a simple replacement of IGBTs or Superjunction devices by wide bandgap devices may bring already some benefits. The full potential of wide bandgap devices, however, will only be reached when being combined with perfectly matching topologies and control. In motor drives e.g. replacing the IGBTs of a B6 bridge with SiC MOSFETs may result in better efficiency in light load and urban drive cycles. However, switching speed limitations down to around 5V/ns to avoid e.g. partial discharge in the insulation of the motor windings or reflections in long cables, will prevent to increase switching frequencies substantially. In contrast, changing the topology from a voltage source inverter to a current source inverter, which creates a continuous voltage on the machine, opens up a completely new optimization range both for the electric machine and its inverter. Similarly, a transition from modular single phase power stages into true 3-phase active frontends using synergetic control options enables much higher power density for on-board chargers.

The presentation will start with a few key characteristics of the involved technologies and their perspective and will highlight system advantages of wide bandgap power devices in a few selected key applications such as Onboard chargers and Motor drive.

Dr. Gerald Deboy received the M.S. and Ph.D. degree in physics from the Technical University Munich in 1991 and 1996 respectively. He joined Siemens Corporate Research and Development in 1992 and the Semiconductor Division of Siemens in 1995, which became Infineon Technologies later on. His research interests focused on the development of new device concepts for power electronics, especially the revolutionary COOLMOS™ technology. Since 2004 he was heading the Technical marketing department for power semiconductors Discretes within Infineon Technologies Austria AG. Since 2009 he is leading a business development group specializing on new fields for power electronics. He is a Sr. Member of IEEE and served in the Technical Committee for Power Devices and Integrated Circuits within the Electron Device Society. He has authored and co-authored more than 90 papers in national and international journals including contributions to three student text books. He holds currently 130 granted international patents and has more applications pending.