Ralf’s GaN & SiC News (August 24, 2023)
Welcome to the latest edition of my newsletter on #siliconcarbide and #galliumnitride. If you want to contribute to it, please reach out to me via [email protected]
Wolfspeed has entered into a definitive agreement to sell its radio frequency business (Wolfspeed RF) to MACOM for approximately $75 million in cash, subject to a customary purchase price adjustment, and 711,528 shares of MACOM common stock, valued at $50 million based on the 30 trading day average for MACOM’s common stock through August 21, 2023. The company expects to close the transaction by the end of this year.
“Given the significant growth we’ve seen in automotive, industrial and renewable energy markets, we believe this is the right time to further focus on scaling our Power device and materials businesses to meet this accelerated demand,” said Gregg Lowe , Wolfspeed President and CEO.
Miscellaneous News
Cost Estimation SiC vs. GaN
Last week, I presented a breakdown of the manufacturing costs associated with GaN power devices presented by Exawatt - now part of CRU . Some time ago, I saw a breakdown of the manufacturing costs associated with SiC power devices provided by Peter Gammon . Now, I have put them into context.
Just take a look at two parameters:
Now, you can draw your own conclusions ?? Which way will you go?
Last week, Alexey Cherkasov had a poll to find out what is the preferred technology for the ongoing or future projects within his network (end users and manufacturers of power semiconductors), and the results positively surprised that SiC is leading with huge gap. Almost 2 of 3 projects will include SiC.
WBG semiconductors are considered for more and more projects, and the results correspond to the market growth forecast for SiC and GaN for the next 5 to 7 years.
For sure, silicon as a very mature technology will continue to grow as well, and its market share will continue to be dominating the power semi market, but good to know that today WBG is not just a hype word, but a technology we rely on and continue to implement.
If designing electronic applications requiring excellent power efficiency, consider using new high-performance gallium nitride (GaN) and silicon carbide (SiC) technologies. These new wide bandgap technologies offer significant advantages over traditional silicon solutions. However, you must consider some design trade-offs, particularly regarding switching losses. For example, the resulting higher di/dt and dv/dt and higher speed operation amplify the frequency oscillation in the circuit, making noise a key consideration. To mitigate this, you must carefully consider your choice of gate resistors, which can eliminate the need for extended dead times that lead to power losses.
Choosing the right low ohmic value gate resistor with the appropriate technology and device construction is crucial in achieving optimal circuit efficiency. These aspects are discussed by Jorge Lugo and Andrew Mason from 威世 .
Gallium Nitride News
Chinese gallium producers need permission to ship abroad under rules effective from Aug.?1, 2023. While some exporters have filed for approval, they expect the process could take several weeks, according to people with knowledge of the issue who declined to be named because the information is not public, as 彭博资讯 reports. The permits will be valid for up to six months, as Dan M. , director of global sales and strategy at Chinese refinery Wuhan Tuocai Technology Co., said.
“Most of the major consumers abroad have material stockpiles, which can sustain their production through this short-term supply crunch,” said Dan Manaig. However, any rejections among the first wave of export applications “would create more real supply anxiety and the market would react with price increases,” he added. Wuhan Tuocai’s exports of gallium and germanium have halted and he expects the whole approval process for new shipments to take six to eight weeks.
The #European GaN foundry BelGaN has launched its 1st Generation 650V eGaN technology into production. It is expected to perform at par with world’s leading GaN foundries and IDMs, especially for high energy-efficient soft switch applications. This is a significant milestone achieved only one year after BelGaN completed the acquisition of the 安森美半导体 Fab in Belgium.
BelGaN’s vision is to become a leading 150- and 200-mm GaN Foundry in Belgium, developing GaN technologies and manufacturing GaN products. Going forward a roadmap of new GaN technologies including Gen2, Gen3, V-GaN, GaN-IC, will be developed and qualified for the high demands of the automotive market, amongst others.
“Getting GaN into production is the first leap to realize our vision to build the GaN Valley. While others took several years to bring GaN process and technology to manufacturing, we are able to do it in record one year leveraging?more than 200 man-years of GaN technology development expertise with over 30 years of high-volume automotive production experiences,” said Rob Willems , General Manager & VP Operations.
A team of researchers from 瑞士苏黎世联邦理工学院 and 英飞凌 combined a three-level Vienna Rectifier (VR) with four isolated Dual-Active-Bridge Converter (DABC) modules and the latest-generation 600V GaN technology. This enables very high switching frequencies of 560 kHz for the VR and up to 330 kHz for the DABCs.
Hence, in this paper, an ultra-compact realization of a 10 kW EV charger module with a power density of 9 kW/dm3 (about 150 W/in3), not including the cold plate, is presented. In this context, a simplified DABC modulation method and straightforward yet accurate (confirmed by experiments) loss models for the DABCs and the VR are introduced, which facilitate a thorough investigation of the optimum synergetic operation of the two stages. This led to a peak efficiency of more than 97%. Further, the synergetic operation of the two-stage system (VR and DABCs) is experimentally verified for the first time, confirming the modeling results and the efficiency advantage.
领英推荐
Yunni Li, Dr. Jon Azurza Anderson , Michael Haider , Jannik Sch?fer, Johann Minib?ck , Jonas Huber , Gerald Deboy , Johann KOLAR , "Optimal Synergetic Operation and Experimental Evaluation of an Ultra-Compact GaN-Based Three-Phase 10 kW EV Charger," in IEEE Transactions on Transportation Electrification, doi: 10.1109/TTE.2023.3297502.
There is a broad consensus that the intrinsic reliability of silicon carbide and gallium nitride power devices is at least as good as that achieved with silicon. The failure modes in these wide-bandgap devices can be different, however, making silicon failure models invalid for reliability predictive purposes.
Understanding these fail modes with new physics-based models can help accurately predict the devices’ lifetimes and hence their reliability in mission-critical applications. This article discusses the test-to-fail methodology adopted by EPC - Efficient Power Conversion (EPC) in its GaN HEMT technology.
The electric vehicle (EV) market is expanding as countries around the world look to reduce their carbon footprint. A key factor driving this growth will be minimizing switching losses in the powertrains of electric vehicles and achieving significant efficiency gains by using smaller batteries that last longer. That’s why VisIC Technologies Ltd. has pioneered the use of GaN power transistors and is using 泰克 equipment to ensure their superior performance.
VisIC Technologies chose Tektronix oscilloscopes because it needed to be able to test the switching efficiency of its GaN transistors through high amplitude (400V) measurements as well as high-frequency oscillation measurements. Essential to the company was the need to ensure measurements taken were “real” and not influenced or limited by the measuring systems that were used. It was also important to use equipment that could focus and measure accurately without introducing too much noise into the process.
Chicony Power selected 英飞凌 ' #CoolGaN and #CoolMOS technology to realize the latest PD3.1 notebook power adapter series for up to 240?W. The new adapter series can provide a 30 percent increase in power density due to the new topology. The new power adapter series can deliver up to 240 watts compared to the 100 W defined in USB 3.0 and charges high performance notebooks such as gaming computers and multimedia workstations via USB-C power delivery. The new power adapter series can be used as a universal power supply for multiple electronic devices.
“We are happy that, together with Chicony Power and our CoolGaN technology, we can realize the new power design capability for PD3.1 adapters, so that every user can easily contribute to decarbonizing the way we work with computers – without compromising on mobility for the sake of performance,” said Adam White , President of Infineon’s Power and Sensor Systems Division.
Silicon Carbide News
Toshiba Electronics Europe GmbH has developed 2200 V SiC MOSFETs for PV inverters. A two-level inverter with the new devices realized higher frequency operation and lower power loss than a conventional three-level silicon IGBT inverter. The new MOSFETs also contribute to the simplification of inverter systems and reductions in their size and weight.
Three-level inverters enjoy the advantage of low switching losses because the voltage applied to switching devices in the inverters during off-state is half the line voltage. Against this, two-level inverters have fewer switching modules than three-level inverters, realizing a simpler, smaller, and lighter system. However, they require semiconductors with higher breakdown voltage, as the applied voltage is equal to the line voltage. Also, demand for semiconductors with both low loss and high breakdown voltage is growing as 1500 V DC line voltage systems are introduced in photovoltaic and other renewable energy markets.
Toshiba has developed 2200 V SBD-embedded SiC MOSFETs for two-level inverters in 1500 V DC voltage systems. The impurity concentration and thickness of the drift layer have been optimized to maintain the same relationship between the on-resistance and the breakdown voltage as our existing products, and also to achieve high resistance to cosmic rays, a requirement for PV systems. It has also been confirmed that embedding SBDs clamped parasitic PN junctions between the p-base regions and the n-drift layer secure high reliability in reverse conduction.
Switching energy loss for the developed all-SiC module is far lower than for the Si module (Si IGBTs + Si fast recovery diodes) with the same 2000 V rated voltage class. Estimates of inverter power dissipation found that the developed SiC module achieves higher frequency operation twice that of a conventional Si IGBT, as well as a 37% lower loss for the two-level SiC inverter against the three-level Si inverter. The higher frequency operation enables downsizing and weight reduction of other system components, such as heat sinks and filters.
WBG Rollercoaster: Will it Drift?
Let's get a bit dynamic in the series of videos. Will it drift? In the next three videos, Frank Heidemann talks about the gate drift in the WBG devices and what the difference between static and dynamic test is. Learn how SET GmbH - Smart Embedded Technologies ' test systems stress the gate with voltage changes to create trapping-effects that result in V_th and R_DS(on) drifts in wide-bandgap semiconductors.
This test is essential because it reveals the loss of efficiency in wide-bandgap components. In addition, Heidemann explains why this effect does not fade, and how it affects the performance. Find out how to detect drifts at the gate before you launch your products to the market.
Wolfspeed posed a worsening operating and net loss for the latest quarter. The company expects rising costs due to factory start-up and operating costs with new facilities. Wolfspeed released its financial results for the fiscal third quarter of 2023, which ended in June. The full-year revenue rose from US$746.2 million in fiscal 2022 to US$921.9 million in fiscal 2023, and year-to-date design-ins reached US$8.3 billion. Wolfspeed's fiscal fourth quarter revenue grew by 3.19% year-on-year to US$235.8 million. Wolfspeed turned a loss in the past quarter, reporting a net loss of US$113.3 million.
Wolfspeed said in a press release that the company is incurring substantial factory start-up costs for factories under construction or production expansion that have not yet commenced generating revenue. Once a newly established facility begins production that generates revenue, the operational expenses previously categorized as start-up costs will predominantly be integrated into the production costs, which will then be accounted for within the cost of revenue.
Silicon carbide (SiC) has developed into a high-performance semiconductor technology in recent years. This goes hand in hand with excellent monocrystalline wafer material and continuously improving process technology as well as understanding of SiC’s fundamental material and device physics.
However, SiC and its derived materials, epitaxial graphene, and SiC’s point defects, have much more to offer: Due to unrivaled material parameters, SiC has also the potential for unprecedented functionalities in the realm of photonics on a chip, highest-Q mechanics, quantum-technology oriented spin physics, and power electronics. This vast design space, which opens up the scope for new experiments and technologies, is yet to be explored.
The scientific symposium “Silicon Carbide as Quantum-Classical Platform” takes place at the FAU Erlangen-Nürnberg on September 14-15, 2023. In this symposium, they will pick up this trail and discuss the possibilities of combining electronics, optics, mechanics, and spin physics to create a platform for combined quantum and classical functionality.
But power electronics will also have a major share in this symposium as prominent power semiconductor people are invited to speak: Peter Friedrichs ( 英飞凌 ), Robert Leonard ( Wolfspeed ), and Hiroyuki Matsunami (Professor Emeritus, Kyoto University ).
Professor of Power Electronic Devices | Founder PGC Consultancy
1 年Thanks for the excellent update as ever Ralf Higgelke, and for including the cost breakdowns from Exawatt and PGC Consultancy. I'd be interested in your take on the two cost stacks!! I think the issues embedded in SiC are clear to see in this - the SiC substrate price, that dominates die costs. For GaN, the challenges are more subtle, not only costs, but yields at the highest current ratings, the lateral layout dictating that these are large devices. Exawatt and PGC Consultancy have been working together on WBG costings now for over a year, and Bex Stone, Adam Dawson and I will always be happy to discuss these in more detail.
CoolSiC? Product Marketing at Infineon Technologies | Founder of Power Semiconductors Weekly | Follow me for the latest power semiconductors market updates |
1 年Thank you for sharing Ralf Higgelke! Great stuff as always.