Power Semiconductors Weekly Vol. 97

New STPOWER Devices from STMicroelectronics

STMicroelectronics has introduced five power-semiconductor bridges in popular configurations, housed in ST’s advanced ACEPACK™ SMIT package that eases assembly and enhances power density over conventional TO-style packages.

Engineers can choose from two STPOWER 650V MOSFET half bridges, a 600V ultrafast diode bridge, a 1200V half-controlled full-wave rectifier, and a 1200V thyristor-controlled bridge leg. All devices meet automotive-industry requirements and are suitable for electric vehicle on-board chargers (OBC) and DC/DC converters, as well as industrial power conversion.

ST’s ACEPACK SMIT surface mounted package delivers the easy handling of an insulated package with the thermal efficiency of an exposed drain. It allows direct-bonded copper (DBC) die attachment for efficient top-side cooling. The 4.6 cm2 exposed metal topside of the ACEPACK SMIT permits easy attachment of a planar heatsink. This creates a space-saving low profile that maximizes thermal dissipation for greater reliability at high power. The module and heatsink can be placed using automated inline equipment, which saves manual processes and boosts productivity.

While minimizing the stack height and enhancing power density, the topside cooling design and 32.7mm x 22.5mm package footprint allow 6.6mm lead-to-lead creepage distance. The tab-to-lead insulation is 4500Vrms. The package also has low parasitic inductance and capacitance.

The SH68N65DM6AG and SH32N65DM6AG 650V-MDmesh DM6 MOSFET half bridges now available in ACEPACK SMIT are AQG-324 qualified. Their Rds(on) (max) of 41mΩ in the SH68N65DM6AG and 97mΩ in the SH32N65DM6AG ensures high electrical efficiency and low thermal dissipation. They can be used in DC/DC converters for both OBC and high voltage to low voltage section. Their multi-role flexibility helps streamline inventory and simplify procurement.

The STTH60RQ06-M2Y 600V, 60A full-wave bridge rectifier comprises ultrafast diodes with soft recovery characteristic and is PPAP capable for use in automotive applications. The STTD6050H-12M2Y 1200V, 60A half-controlled single-phase AC/DC bridge rectifier is AEC-Q101 qualified and has high noise immunity with dV/dt of 1000V/μs.

The STTN6050H-12M1Y is a 1200V, 60A half bridge that comprises two internally connected thyristors (silicon-controlled rectifiers – SCRs). AEC-Q101 qualified, it can be used in automotive OBCs and charging stations and industrial applications such as AC/DC conversion in motor drives and power supplies, single- and tri-phase controlled rectifier bridges, totem-pole power-factor correction, and solid-state relay.

Resonac and Infineon Technologies Strengthen Cooperation in SiC Materials for Power Semiconductors

Resonac Corporation (Resonac) has concluded new multiyear contracts with Infineon Technologies AG (Infineon) to continue supplying SiC materials for power semiconductors to Infineon and cooperatively developing technologies related to SiC materials. Resonac concluded these new contracts to complement and expand the preceding supply and joint development contracts concluded in 2021, thereby strengthening the partnership with Infineon.

Resonac expects this partnership will enable Infineon to apply Resonac’s SiC materials to various power semiconductor products, and now Resonac plans to provide Infineon with SiC materials of 200mm (8-inch) diameter, in addition to those of 150mm (6-inch) diameter. Furthermore, Resonac will accelerate improvement in technologies for and product quality of SiC epitaxial wafers through reinforced joint development activities with Infineon. Resonac and Infineon are confident that the strengthened partnership of the two companies will support rapid growth of the market for SiC materials, which are next-generation materials for semiconductors, and contribute to stabilization of the supply chain of SiC-based power semiconductors.

The Resonac Group aims to contribute to sustainable development of global society as a “Co-creative chemical company,” and the Group positions its SiC epitaxial wafer business as a next-generation business because SiC-based power semiconductor realizes efficient use of energy. Under a motto of “Best in Class,” the Resonac Group will continue providing the market with high-performance and highly reliable SiC products, thereby contributing to the proliferation of SiC power semiconductors.

Infineon Technologies Increases Focus and Investment into Core Semiconductor Development

Infineon Technologies AG announced that Micross Components, Inc. (“Micross”) has entered a definitive agreement to purchase Infineon’s HiRel DC-DC converter business including its hybrid and custom board-based power products. This sale will enable Infineon to extend its focus and investments on core semiconductor developments for the high-reliability market, while deemphasizing businesses that require more customized product offerings for the high-reliability industry. The deal is expected to close in the first quarter of calendar year 2023.

“Infineon is pleased to have reached an agreement with Micross to provide a more strategic home for our HiRel DC-DC converter business,” said Bob LeFort, President of Infineon Technologies Americas. “We believe this sale is in the best interest of both companies, our customers, employees, and shareholders. This transaction enables Infineon to remain focused on the HiRel business areas that benefit from Infineon’s leading semiconductor technologies. We look forward to working with Micross to ensure a seamless transition for our customers and employees.”

Vince Buffa, Chairman and CEO of Micross, said, “We are pleased to have reached an agreement with Infineon on their HiRel DC-DC converter business and to have the opportunity to partner with their highly experienced team which further expands Micross’ design capabilities. We are excited about the significant proprietary power management IP that combined with their state-of-the-art manufacturing capabilities and product portfolio leads the way for advancement of innovative solutions. We will be better positioned to produce an even wider range of high-quality products for our customers. Together, we plan to pursue several compelling opportunities to further realize our exciting growth prospects, all while upholding excellent quality and service to our customers.”

The HiRel DC-DC converter business is a leading provider of high reliability DC-DC power conversion solutions for the toughest environments, including outer space, and will operate under the Micross Hi-Rel Products business segment. These DC-DC converter products are complete power solutions, including main power converter, control circuits, filters, and housing.

“We are dedicated to our customer and partner base and will continue to leverage our existing resources and talent to develop innovative solutions together,” said Chris Opoczynski, Sr. Vice President and General Manager, HiRel Business Line, Infineon Technologies. “In our retained HiRel businesses, Infineon will strengthen its focus on these target applications, along with others that demand the highest reliability and highest performance. We are committed to the mission-critical space, defense, and aerospace industries.”

CVD Equipment Receives Additional Order for PVT-150 Systems for SiC Growth

CVD Equipment Corporation, a leading provider of chemical vapor deposition systems, announced that it has received an additional order for ten high performance PVT-150 systems. The systems will be used to grow 150 mm diameter monocrystalline silicon carbide (SiC) boules, which are subsequently processed into SiC wafers used in power electronics. The systems are scheduled for delivery in the first half of 2023.

SiC power electronics allow for higher power density and greater efficiency than their silicon-based predecessors, enabling faster charging times and increased performance. The automotive industry is driving the uptake in SiC, given its reputation as a more efficient alternative to silicon. The adoption of SiC in electric vehicle inverters allows for greater efficiency, increasing range and/or reducing battery size. Additionally, SiC used in charging infrastructures allows for higher performance and faster charging, which has been an accelerating trend for the electric vehicle industry.

As the demand for SiC devices for high power electronics continues to increase for electric vehicles, energy, and industrial applications, Physical Vapor Transport (PVT) is the leading manufacturing method used to grow SiC boules for wafer production. CVD Equipment has expertly engineered PVT systems to support the production of high-quality SiC boules for high yield SiC wafers. Presently offering 150 mm crystal growth systems, we are committed to supporting the critical high volume production needs for the industry and further supporting the evolution to systems of 200 mm and above.

“CVD Equipment Corporation is ramping-up our commercialization of the PVT systems to meet the growing needs of the High-Power electronics industry. Our 40 year legacy of developing process equipment and our vertical integration has positioned us as a leading manufacturer of high quality SiC PVT systems. Our sights are set to facilitate the industry’s growth and electrification of the future.” said Emmanuel Lakios, President, and CEO of CVD Equipment Corporation.

Arizona State University Developing Transistors Made of Diamond and Boron Nitride

Power transistors to regulate the flow of electrical power have traditionally been made with silicon, while more advanced transistors are made of silicon carbide (SiC) or gallium nitride (GaN). But Trevor Thornton, a professor of electrical engineering in Arizona State University’s School of Electrical, Computer and Energy Engineering (part of the Ira A. Fulton Schools of Engineering), is leading a team researching the use of two new transistor materials: diamond and boron nitride (BN).

Thornton’s team is conducting its research through ASU’s Advanced Materials, Processes, and Energy Devices Science and Technology Center (AMPED STC). AMPED’s goal is to develop materials and technologies with industry partners to support the mission of Arizona’s New Economy Initiative, which aims to improve Arizona’s competitiveness in developing advanced technology. AMPED specifically looks to develop technologies and materials used in the construction of batteries, solar electricity generation and power electronics.

The research team includes Thornton and other ASU faculty members including Terry Alford, a professor of materials science and engineering, Stephen Goodnick, a professor of electrical engineering, and Robert Nemanich, a Regents Professor of physics, as well as doctoral students in electrical engineering and materials science and engineering. They are working with Northrop Grumman Mission Systems as the industry partner for the project.

Thornton says that diamond is under investigation as a material for transistors because of its high thermal conductivity compared with existing materials, e.g. 8–10 times greater than gallium nitride. Harnessing diamond’s full potential could shrink the size of transistors by 90%, it is reckoned. Diamond also has a high breakdown field — i.e. it can handle a high voltage relative to most materials before failure — suitable for applications that handle large amounts of power.

While diamond is the team’s chosen material for the main body of a transistor, they are investigating the use of boron nitride for the transistors’ electrical contacts. Like diamond, boron nitride has a high breakdown field and high thermal conductivity. Goodnick’s role is concerned primarily with computer modeling and simulation of the use of boron nitride transistors.

The team expects that, by combining their knowledge of how diamond and boron nitride work as transistor materials, they can create transistors made from both materials. The hope is that the materials complement each other and work even better together than individually.

“Ultra-wide-bandgap semiconductor materials like diamond and boron nitride are expected to lead to more efficient energy conversion using less power with much smaller components,” Goodnick says. “This improves the future energy grid, which is essential for the ongoing transition toward renewable energy and electrification of the transportation sector.”

This research has applications that would be especially useful to communications technologies, says the team Many satellites run on solar power, which requires transistors to turn the electricity into a form usable by the satellite. “You can’t launch a power substation into space,” Thornton says. “Any improvement on size and weight in a satellite has a huge impact.”

Another communications technology the transistors could improve is the cell-phone tower. Transistors convert power to the form needed to produce radio frequency waves that cell phones use.

One of the biggest challenges faced when designing and operating cell-phone towers is keeping them cool, notes Thornton. This is especially the case in a hot environment like Phoenix.

The power transistors in older cell-phone towers are typically made from silicon, while those in newer 5G systems will use gallium nitride. Thanks to its improved heat dissipation, Thornton’s team expects transistors made from diamond and boron nitride to greatly reduce the cooling power needed for cell towers, making it far easier to prevent them from overheating.

While the project with Northrop Grumman Mission Systems focuses on communications technology, transistors made from diamond and boron nitride also have applications in power conversion for electrical systems and for the electricity grid. These more efficient materials could reduce the size requirements for electricity grid substations, which typically occupy an area of land the size of a building.

Nemanich, a faculty member in the ASU Department of Physics, leads the ‘Ultra Materials for a Resilient, Smart Electricity Grid’ (ULTRA) Energy Frontier Research Center (EFRC) conducting research on power electronics. He also leads a lab for growing artificial diamond materials, which will be used by Thornton’s team in their research.

“We have been growing diamond for electronic devices for the last 10 years,” Nemanich says. “Our diamond deposition lab has unique capabilities for the development of electronic materials and devices,” he believes.

In addition to Thornton’s electrical engineering expertise and Nemanich’s work with diamond as an electronic material, Alford, a faculty member in the School for Engineering of Matter, Transport and Energy (part of the Fulton Schools), provides his expertise on materials science.

Alford is working on materials characterization, analyzing the properties of the materials that the team is investigating. He also leads a part of the research looking into the use of new types of metallic electrical contacts connected to diamond as a substrate, and he co-advises a materials science and engineering doctoral student involved in the research with Thornton.

Working with Thornton’s team at the AMPED STC has given Alford the chance to conduct research that differs from his normal topics. He believes that his perspective as a materials scientist can help the team to achieve its goals. “We bring to the table a desire to understand the impact of a material’s defects,” Alford says. “We want to be able to understand those defects and how they impact a device’s performance.”

The transistor research project is funded for two years through the AMPED STC partnership with Northrop Grumman Mission Systems. However, to fully realize the transistors’ potential for widespread applications, Thornton says it could take longer.

“We’ll have breakthroughs, but I don’t see it being widely adopted in the way we’re talking about for five to 10 years,” he says. “It’s that kind of medium- to long-term research of which some applications will happen quicker, while others will be 10 years for widespread consumer applications.”

IDTechEx Webinar: The Evolution of EV Thermal Management and What’s Beyond 2022?

Thermal management continues to be a key topic for electric vehicle (EV) design. Early trends in the market largely revolved around the adoption of active cooling for the battery pack, now this is the industry standard. However, batteries, motors, and power electronics in EVs continue to evolve with developments of cell-to-pack designs, directly oil-cooled motors, and silicon carbide power electronics being just a few of the key trends that will impact thermal management strategies across the key driveline components in an EV.

As the thermal management market evolves, opportunities arise for materials companies, component suppliers, vehicle designers, and other players in the rapidly growing EV industry.

This webinar is based on content from IDTechEx’s new report on “Thermal Management for Electric Vehicles 2023-2033”. The webinar will cover various market drivers and trends in thermal management for batteries, motors, and power electronics. Focusing on recent developments in the market over the last 1-2 years.

Key Take-Aways:

An overview of thermal management in an EV
Trends in battery thermal management: active cooling adoption and immersion
Emerging trends in battery design impacting thermal management: cell-to-pack, 800V, etc.
Fire protection material options
Electric motor thermal management trends: water-glycol, oil, and strategy
Power electronics package trends: wide bandgap, SiC, wire bonds, die attach, thermal interface materials
Power electronics cooling trends: direct, double-sided, water-glycol, direct oil cooling

Date: January 19, 2023
Time: 11 AM CET

Subscribe to Power Semiconductors Weekly and watch it on YouTube every Tuesday.

If you prefer a monthly update about the world of power semiconductors delivered to your e-mail address, please, subscribe to Marketing Psycho Power Semiconductors newsletter