Ralf’s GaN & SiC News (August 11, 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]
Miscellaneous News
The U.S. Department of Energy (DOE) issued a Critical Materials Assessment report which includes silicon carbide and gallium nitride.
The analysis identifies seven materials, including gallium, as critical in the short term (2020–2025), silicon carbide as near critical. Over the medium term (2025–2035), the importance and supply risk scores for SiC shifts to critical. This may create a supply chain bottleneck for wide-bandgap power electronics, the DOE says.
Diamond has semiconductor properties superior to those of Si, GaN, and SiC, such as a high thermal conductivity, insulation, and a wide bandgap. Therefore, this material is ideal for use in high-power semiconductors. However, the hardness of diamond makes it challenging to slice a thick diamond crystal into thin wafers using mechanical processing techniques, such as wire or annular saws.
To restrict undesirable cracks, Japanese scientists from 千葉大学 (Chiba University) devised a laser irradiation sequence and developed a cutting method. This slicing technology will potentially pave the way toward the realization of diamond semiconductors.
Kosuke Sakamoto, Daijiro Tokunaga, Sho Itoh, Hirofumi Hidai, Souta Matsusaka, Takashige Omatsu, Koji Koyama, Seong-Woo Kim, Noboru Morita, Laser slicing of a diamond at the {100} plane using an irradiation sequence that restricts crack propagation along the {111} plane, Diamond and Related Materials, Volume 136, 2023, 110045, ISSN 0925-9635, https://doi.org/10.1016/j.diamond.2023.110045.
Efficient system integration is the key to exploiting the full potential of WBG semiconductors. Power electronics developers need to take into account that high switching speeds, high frequencies and high power densities place special demands on the system components.
This 2-day ECPE European Center for Power Electronics tutorial taking place September 28-29, 2023, in Strasbourg (France) addresses all aspects of WBG system integration from the choice of semiconductor components and design options to how to cope with parasitics, EMC and inductance at high switching frequencies. Another topic is test methods – both for electric tests of new power semiconductor components as for the robustness and reliability of modules and systems.
Course Instructors:
At the recent PowerUP Expo Virtual Conference, a panel discussion, “SiC and GaN Solutions: Recent Developments and Next Challenges to Overcome,” was moderated by Maurizio Di Paolo Emilio , Editor-in-Chief of Power Electronics News and EEWeb.com . This article is a summary of this discussion which focused on current and forecast future applications and detailed some of the challenges faced by the industry.
The panelists were
Rob Gwynne , CEO of QPT , has recorded a series of videos to explain the benefits of the proprietary approach the company is taking to take full advantage of GaN technology.
In the third video, he discusses the current market leaders in SiC and GaN, and why both of these solutions still have major efficiency problems compared to unleashing the full potential of GaN at high power.
Gallium Nitride News
领英推荐
Together with its partner Yaskawa Electric Corporation , Transphorm Inc. has demonstrated up to 5?μs short-circuit withstand time (SCWT) on a GaN power transistor with a patented technology. According to the company, this achievement is the first of its kind on record, marking an important milestone for the industry as a whole. It proves Transphorm GaN’s ability to meet the required short circuit capabilities of rugged power inverters such as servo motors, industrial motors, and automotive powertrains served traditionally by silicon IGBTs or silicon carbide (SiC) MOSFETs—an over $3 billion GaN TAM over the next 5 years.
The short-circuit technology has been demonstrated on a newly designed 15 mΩ 650 V GaN device. Notably, that device reaches a peak efficiency of 99.2% and a maximum power of 12 kW in hard-switching conditions at 50 kHz. The device demonstrated not only performance, but also reliability, passing high-temperature high-voltage stress requirements. The full description explaining the SCWT achievement, the demonstration analysis, and more is expected to be presented at a major power electronics conference next year.
“Standard GaN devices can withstand short-circuit for only a few hundredths of nanoseconds, which is too short for fault detection and safe shut-down. However, with our cascode architecture and key patented technology, we were able to demonstrate short-circuit withstand time up to 5 μs with no additional external components, thus retaining low cost and high performance,” said Umesh Mishra, Ph.D. , CTO and Co-Founder, Transphorm.
Infineon Technologies Canada Inc. has partnered with ACEpower to expedite the widespread adoption of GaN technology in electric vehicles. By harnessing GaN Systems’ cutting-edge power semiconductors, extensive expertise in EV power electronics, and ACEpower’s exceptional track record in high-power system design and high-volume manufacturing capabilities, this partnership will accelerate the GaN-based electric vehicle power market in #China.
Future initiatives encompass the joint development of high-power density GaN-powered OBCs rated at 6.6kW and 11kW for electric vehicles, solidifying their commitment to driving innovation and advancing the power industry.
“We are delighted to announce our partnership with GaN Systems to accelerate GaN adoption in electric vehicles. Our longstanding relationship with GaN Systems, coupled with their unrivaled expertise in high reliability, automotive-qualified GaN semiconductors—a vital component for electric vehicles—brings great business opportunities in the fast growth Chinese EV market,” Albert Wang, CEO of ACEpower.
Silicon Carbide News
There has been a flurry of impactful collaborations announced in the last year within the power SiC market, and interestingly, not just at the wafer and material level as previously seen, but across the entire power SiC ecosystem. Yole Intelligence ’s compound semiconductor analysts, Poshun CHIU , Ezgi Dogmus, PhD and Taha Ayari, PhD investigate and deliver today a relevant analysis of the motivations behind these recent announcements.
The recent announcements have not been related solely to design-wins. While traditionally most of the activity has been focused on the wafer level, the industry is now experiencing a greater number of partnerships across the entire ecosystem, including at the device and system level. With multiple announcements of capacity expansion, SiC wafer supply becomes less of a bottleneck in the coming years. Players across the entire supply chain are forming relationships to solidify their position within the maturing market. Motivations such as securing wafer supply, seeking investment to fund capacity expansions, and qualifying new technology or entering new markets all play a role. Find out more about the motivations of the different players in this article.
ROHM Co., Ltd. saw its operating profits decline by 21.5% in April–June 2023. Its automotive sales increased by 14.9% year-over-year, the only segment that enjoyed growth. President and CEO Isao Matsumoto had said Rohm will continue investing in SiC technology while it contains risks.
Rohm plans to inject JPY510 billion ($3,6 billion) into SiC by the end of March 2028. Matsumoto said in July 2023 that the company will invest JPY40 billion to JPY50 billion ($280 million to 350 million) in the technology annually on average in the next seven years. While the investment encompasses some risks, it is necessary for the company's growth.
The adoption of SiC started in China and has arrived in Europe, the US and Japan, Matsumoto said. It also expands from premium to affordable vehicle models. He said the demand for SiC has great potential, making the technology a reasonable investment target.
Rohm will contribute JPY300 billion ($2,1 billion) to the Toshiba Electronics Europe GmbH buyout plan initiated by the Japanese Industrial Partners (JIP) to facilitate the collaboration for power semiconductors between Rohm and Toshiba. Rohm said it will apply for loans to fulfill the commitment.
Solar power inverters and energy storage system (ESS) applications along with other renewable systems are modernizing energy grids to improve resilience, meet global energy requirements and reduce their overall carbon footprint. These systems must be as efficient as possible in rugged environments as well as compact and inexpensive.
Silicon carbide technology runs cooler and faster and enables smaller and lighter power electronics with higher energy efficiencies because of innovation and best practices at the PCB design stage. In this article, Wolfspeed reviews some of the challenges and tips for PCB layout design at the device, sub-circuit, and system levels.
The application of SiC MOSFETs in the field of electrified vehicles has brought many benefits, such as higher efficiency, higher power density, and simplified cooling system, and can be seen as an enabler for high-power fast battery charging. This article from researchers at 德国亚琛工业大学 reviews the benefits of SiC MOSFETs in different electrified vehicle (EV) application scenarios, including traction inverters, on-board converters, and off-board charging applications.
However, replacing silicon IGBTs with SiC MOSFETs introduces several new technical challenges, such as stronger electromagnetic interference (EMI), reliability issues, potential electric machine insulation failure due to high transient voltages, and cooling difficulties. Compared to mature silicon-based semiconductor technologies, these challenges have so far hindered the widespread adoption of SiC MOSFETs in automotive applications. To fully exploit the advantages of SiC MOSFETs in automotive applications and enhance their reliability, this paper explores future technology developments in SiC MOSFET module packaging and driver design, as well as novel electric machine drive strategies with higher switching frequencies and optimized high-frequency machine design.
Bufan Shi , Anna Isabel R. , Yingxu Liu, Haoran Wang , Yu Li , Prof. Stefan Pischinger , Univ.-Prof. Dr.-Ing. Jakob Andert : A review of silicon carbide MOSFETs in electrified vehicles: Application, challenges, and future development. IET Power Electron. 1–18 (2023). https://doi.org/10.1049/pel2.12524