Elastic carbon films: The answer to on-chip energy storage?

By eeNews Europe

The international team of researchers led by Drexel University’s Yury Gogotsi, Ph.D. , and Patrice Simon, Ph.D., of Paul Sabatier University in Toulouse, France, have confirmed a process for making carbon films and micro-supercapacitors that allows microchips and their power sources to become one and the same.

The discovery, which was reported in the journal Science, is the culmination of years of collaborative research by the team who initially created the carbide-derived carbon film material for micro-supercapacitors and published the concept paper in Science in 2010. Since then, their goal has been to show that it is possible to physically couple the processing center of an electronic device – the microchip – with its energy source.

"This has taken us quite some time, but we set a lofty goal of not just making an energy storage device as small as a microchip – but actually making an energy storage device that is part of the microchip and to do it in a way that is easily integrated into current silicon chip manufacturing processes," says Simon, who led the research under the aegis of the French research network on electrochemical energy storage (RS2E), a spin-off of Le Centre National de la Recherche Scientifique (CNRS) and France’s Ministry of Research. "With this achievement, the future is now wide open for chip and personal electronics manufacturers."

The development confirms a belief that the group has held since the materials were first fabricated – that the films are versatile enough to be seamlessly integrated into the systems that power silicon-based microchips that run devices from your laptop to your smart watch.

The challenges that the group faced in the development of the material were questions about its compatibility, its mechanical stability and durability for use on flexible substrates. With these answered, it opens up a myriad of possibilities for carbon films to work their way into silicon chips – including building microscale batteries on a chip.

"The place where most people will eventually notice the impact of this development is in the size of their personal electronic devices, their smart phones, fitbits and watches," says Gogotsi, Distinguished University and Trustee Chair Professor in the Department of Materials Science Engineering who directs the A.J. Drexel Nanomaterials Institute in Drexel’s College of Engineering.

"On-chip energy storage is needed to create the Internet of Things – the network of all kinds of physical objects ranging from vehicles and buildings to our clothes embedded with electronics, sensors and network connectivity, which enables these objects to collect and exchange data. This work is an important step toward that future."

The researchers’ method for depositing carbon onto a silicon wafer is consistent with microchip fabrication procedures currently in use, thus easing the challenges of integration of energy storage devices into electronic device architecture. As part of the research, the group showed how it could deposit the carbon films on silicon wafers in a variety of shapes and configurations to create dozens of supercapacitors on a single silicon wafer.

For more, see the paper in the journal Science: "On-chip and freestanding elastic carbon films for micro-supercapacitors."

Related articles:
Micro-supercapacitor manufacturing process could boost wearable tech
3D microbattery promises on-chip power for micro-scale devices
Wire-shaped power source can be woven into clothing
Flat supercaps address IoT device design challenges