Flex-RV chip. a, Layout of the 9 mm × 6 mm test chip containing two Flex-RV microprocessors. b, Die photo of the test chip taken under a microscope. Credit: Nature (2024). DOI: 10.1038/s41586-024-07976-y

Engineers develop a bendable, programmable, non-silicon microprocessor that requires only 6 mW of power

by · Tech Xplore

A team of microchip engineers at Pragmatic Semiconductor, working with a pair of colleagues from Harvard University and another from Qamcom, has developed a bendable, programmable, non-silicon 32-bit RISC-V microprocessor. Their research is published in the journal Nature.

Over the past several years, hardware manufacturers have been developing bendable microprocessors for use in medical applications. A bendable device with bendable components would allow for the creation of 24-hour sensors that could be applied to any part of the body.

For this new project, the research team developed an inexpensive circuit board that could be bent around virtually any curved object. The material was made using indium gallium zinc oxide instead of the more rigid silicon.

During testing, the researchers found that a flat sample could be bent all the way around a pencil without cracking. They also found that the material was amenable to IGZO transistor printing. The result was a RISC processor the team calls the Flex-RV.

The demonstration chips thus far have a core size of 17.5 square millimeters and 12,600 logic gates, which limits their speed to 60 kHz. They also run the open-source RISC-V architecture. The processors would not be fast enough for major applications, but are more than capable of processing vital stats such as heartbeat rate or body temperature.

The researchers note that the processors require only 6 mW of power. The team has calculated that the processors could be made for as little as US $1, making them disposable.

Testing thus far has shown that the processor is capable of running while bent into many configurations. The team suggests an ideal application would be an ECG patch placed on the chest of a patient, along with electrodes that could pick up heartbeat characteristics, allowing a doctor to monitor arrhythmia or other ailments. Because the processor would be applied to the chest, external processing, such as by a smartphone, is not required.

More information: Emre Ozer et al, Bendable non-silicon RISC-V microprocessor, Nature (2024). DOI: 10.1038/s41586-024-07976-y
Journal information: Nature