Heat-resistant sensing and computing chips made of silicon carbide could advance aircraft, electric and gas-powered vehicles, renewable energy, defense and space exploration—and University of Michigan researchers are leading a multimillion dollar collaborative effort to bring more of them to market.
Funded by the Silicon Crossroads Microelectronics Commons Hub, the project is launching with $2.4 million in initial funding, and could receive up to $7.5 million over three years.
Engineers at NASA's Glenn Research Center have been exploring the potential of silicon carbide, or SiC, as a high-performance semiconductor for decades. SiC devices can handle higher voltages, temperatures and radiation levels than silicon alone. With an eye toward exploring the surface of Venus, they built a SiC circuit that can withstand 930 F (500 C) for thousands of hours. NASA Glenn has also shown packaged device operation over a 1,800 F (1,000 C) temperature span from -310 F (-190 C) to 1,490 F (812 C) with relevance across aerospace.
SiC could be valuable for more than space missions—it's increasingly used in power electronics for electric vehicles and solar and wind energy systems. However, these applications aren't making the most of its resilience to extreme conditions.
The new project will scale up NASA's technology and manufacturing process to a modern wafer size and democratize SiC chip design. Along with NASA, collaborators include GE Aerospace Research in Niskayuna, New York; Ozark Integrated Circuits (Ozark IC), a technology firm in Fayetteville, Arkansas; and Wolfspeed, a North Carolina-based semiconductor manufacturer.
While the technology could be useful in a broad range of sectors, the project will focus on aerospace, including electronics and sensors that make aircraft engines more reliable and help optimize their size, weight and power. A key goal is the demonstration of a packaged actuator for aerospace or on engine applications. Actuators convert electrical signals to mechanical motion and play an important role in control systems.
Partnering with industry and government
"NASA, GE Aerospace and Ozark IC have done an amazing job of developing this technology, which is very impactful for a variety of applications. This project will provide a critical pathway to advance and commercialize that technology," said principal investigator Becky Peterson, associate professor of electrical and computer engineering and director of the U-M Lurie Nanofabrication Facility.
"We need advanced semiconductors produced domestically that can perform in these challenging high temperature environments."
In the project, NASA Glenn and GE Aerospace will work together to scale what's referred to as the high temperature SiC junction field effect transistor, or JFET, fabrication process from 100- to 150-millimeter wafers.
“SiC-based high temperature electronics will be a key enabler for delivering new sensor and actuator functionality that improves the capability of future DoD engine platforms. Beyond jet engines, the ability to handle more extreme temperature capabilities could open exciting new applications in control and sensing for hypersonic applications," said Aaron Knobloch, platform leader, controls and electrical systems at GE Aerospace Research.
Ozark IC, which has worked with NASA Glenn through the NASA Small Business Innovation Research program and licensing offices for many years, will support packaging, integration and process commercialization. Ozark IC has shown a path for the technology working to over 1,400 F (800 C) integrated with advanced packaging.
This program builds on Ozark IC's existing Department of Defense work with NASA where DARPA has supported SiC JFET-R technology transition to GE Aerospace's 100 mm facility in New York, and its application to aerospace sensing through the DARPA High Operational Temperature Sensors (HOTS) program.
Wolfspeed, a pioneer and leader in SiC wafer production, will provide the specialized SiC wafers necessary for these devices building on its deep expertise and capacity in epitaxy of SiC. Wolfspeed and the U.S. Department of Commerce are finalizing a proposed $750 million direct funding package to support the expansion of Wolfspeed silicon carbide production in North Carolina and New York. In addition, Wolfspeed will consult with the team on design for commercialization.
"Ozark IC has been working with NASA and GE Aerospace in bringing SiC technology into aerospace and energy for many years. We couldn't be more thrilled to work with Michigan and Wolfspeed to help scale the technology up to 150 mm with advanced packaging and integration," said Matt Francis, CEO and founder of Ozark IC.
Michigan Engineering researchers will refine and standardize a process development kit and transistor models. They will create libraries of commonly-used circuit blocks to make the SiC technology more accessible to integrated circuit designers.
"We'll test the devices and circuits made by NASA and GE Aerospace and packaged by Ozark IC and work together to standardize those pieces," Peterson said. "And we'll use the data to create process development kits and open electronic design automation, or open EDA, software that can help automate the design of integrated circuits, and model their performance. We want to develop advanced refined models so that future users have all the tools they need to design and manufacture commercial products in this exciting technology."
To do this, a team led by David Wentzloff, U-M professor of electrical and computer engineering, will add to the unique open-source tools they've developed for designing analog and mixed-signal circuits. These circuits are crucial for tasks such as managing power, converting real-world data from sensors to digital information for processing, and driving actuators and controllers in jet engines. Analog circuits complement the digital ones that perform processing and memory tasks, for example. While open-source design tools for digital circuits are becoming increasingly common, U-M brings them into the analog realm to implement analog and digital systems on a SiC chip.
"Our system is unlike other prior analog circuit design automation tools," Wentzloff said. "The primary difference is we build on top of very mature digital design automation tools—in short, analog circuits designed with digital design automation tools. This speeds up the design of analog and mixed-signal circuits and makes it more accessible to a wide range of designers. You no longer need highly specialized analog circuit design skills."
Improving aerospace engine reliability
Today's silicon-based electronics used in engine control systems are limited to 257 F (125 C) and must be protected from heat through complex and heavy cooling systems or located in cooler areas of the engine. SiC electronics can function in hot areas within engines and their exhaust systems. The technology established in this project will enable new sensor and actuator functionality, flexible modular control systems, lower weight and simpler engine electrical system architectures. Due to SiC's ability to handle extreme temperatures, SiC electronics can also advance emerging hypersonic aircraft systems which operate at temperatures far beyond the capabilities of silicon.
The project is titled: "Improving Engine Reliability and SWAP with 350-500 C SiC Electronic Systems." It is one of 34 technical projects funded in 2024 by the U.S. Department of Defense through the Microelectronics Commons program, established by the CHIPS Act to expand U.S. leadership in microelectronics.
The University of Michigan is a founding member of the Silicon Crossroads Microelectronics Commons Hub, led by the Applied Research Institute. The SCMC Hub is an innovation ecosystem of diverse partners driven to accelerate expansion of America’s microelectronics base by leveraging strong collaborative practices that strategically support innovation, workforce development, and infrastructure needs to achieve domestic microelectronics excellence.