Imec, KU Leuven and PragmatIC Demonstrate Fast 8-Bit Flexible Microprocessor

At the 2022 International Solid-State Circuits Conference (2022 ISSCC), imec, KU Leuven and PragmatIC Semiconductor present the fastest 8-bit microprocessor in 0.8µm metal-oxide flexible technology capable of running real-time complex assembly code.

The microprocessor was implemented with a unique digital design flow that allowed the creation of a new standard cell library for metal-oxide thin-film technologies – relevant for designing a broad range of loT applications. The thin-film technology offered by imec’s foundry partner PragmatIC Semiconductor was key to integrate the approximately ~16,000 metal-oxide thin-film transistors on a 24.9mm2 flexible chip.

Flexible electronics based on thin-film transistor technology is preferred over Si CMOS-based electronics for applications requiring low-cost, thin, flexible and/or conformable devices. The technology already made inroads in health-patch sensors and RFID labels, and as a driver for flat panel displays. The missing piece is a flexible microprocessor to perform more complex signal processing calculations – as such adding compute functionality to a broad range of IoT applications.

Imec has designed a flexible 8-bit microprocessor in 0.8µm indium-gallium-zinc-oxide (IGZO)-transistor technology, able to perform such complex computations.

“Our flexible microprocessor shows excellent characteristics for IoT applications, including high speed (71.4kHz max operating speed), low power consumption (11.6mW when running at 10kHz, 134.9mW at max operating speed), and high transistor integration density (~16,000 transistors with 0,8µm gate length in a 24.9mm2 chip),” said Kris Myny, principal scientist at imec.

With the new microprocessor, imec addressed major challenges related to the design of unipolar systems.

To fabricate the flexible microprocessor, imec teamed up with foundry partner PragmatIC, whose FlexIC Foundry offers rapid prototyping and high-yield volume manufacturing of flexible integrated circuits.

“Until recently, there was no mature and robust technology available for integrating such a large number of thin-film transistors with sufficient yield. Our pioneering  FlexLogIC fab now enables the rapid turnaround of such complex new designs at an ultra-low cost, delivering ICs on thin and flexible wafers,” said Brian Cobb, VP product development at PragmatIC.