Researchers have developed a technique to implement silicon large-scale integration chips in a very thin film of thickness. This fabrication method has the potential to realize a low-invasive flexible device for monitoring brain activity. This study will contribute to the development of brain-machine interface systems.
There seems to be a race to develop practical neural interfaces that are implanted in a minimally invasive fashion and that don’t require wires sticking out of the scalp. We just reported on stentrodes that can be delivered into the brain through the vasculature and now we are learning of a new ability by researchers at Toyohashi University of Technology in Japan to create very thin films that have large-scale integrated chips. While there haven’t been any animal studies of the technology, the researchers believe that they will be able to implant devices into the brain that have on-board power, data processing capabilities, and an antenna to communicate with external devices.
The films are about 10 μm in thickness and are flexible, including the built-in antenna. These devices can conform to the shape of the brain and eventually integrate components specific to the application.
Here’s some details from the study abstract in journal Sensors:
The proposed co-design method optimizes the system architecture, and can help avoid the use of external matching components, resulting in the realization of a small-size system. In addition, the technique employed to assemble a silicon large-scale integration (LSI) chip on the very thin parylene film (5 μm) enables the integration of the rectifier circuits and the flexible antenna (rectenna). In the demonstration of wireless power transmission (WPT), the fabricated flexible rectenna achieved a maximum efficiency of 0.497% with a distance of 3 cm between antennas. In addition, WPT with radio waves allows a misalignment of 185% against antenna size, implying that the misalignment has a less effect on the WPT characteristics compared with electromagnetic induction.