This image shows the layered structure of the carbon films on silicon chips. Image: A. Demortiere/LRCS.
This image shows the layered structure of the carbon films on silicon chips. Image: A. Demortiere/LRCS.

After more than half a decade of speculation, fabrication, modeling and testing, an international team of researchers has confirmed that their process for making carbon films and micro-supercapacitors will allow microchips and their power sources to become one and the same. The team was jointly led by Yury Gogotsi from Drexel University and Patrice Simon from Paul Sabatier University in Toulouse, France.

The discovery, recently reported in Science, is the culmination of years of collaborative research by the team, which initially created the carbide-derived carbon film material for microsupercapacitors and published the concept paper in Science in 2010. Since then, their goal has been to show that it's 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," said Simon, who led the research under the aegis of the French research network on electrochemical energy storage (RS2E). "With this achievement, the future is now wide open for chip and personal electronics manufacturers."

It confirms a belief that the group has held since the materials were first fabricated – that these films are versatile enough to be seamlessly integrated into the systems powering the silicon-based microchips that run everything from laptops to smart watches.

The challenges that the group faced in developing the carbon film revolved around its compatibility, its mechanical stability and its durability when used with flexible substrates. With these challenges now overcome, 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 and watches," said Gogotsi, a professor in the Department of Materials Science Engineering and director of the A.J. Drexel Nanomaterials Institute in Drexel's College of Engineering.

"Even more importantly," Gogotsi adds, "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 smoothing the process of integrating energy storage devices into electronic device architecture. As part of their 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.

Supercapacitors are a desirable technology for use in microelectronics because they can store a great deal of energy for their size, can be charged and discharged extremely quickly, and their lifespan is nearly limitless. With this discovery, the path is now clear for microchip manufacturers to take a big step forward in the way they design their products.

Beyond energy storage applications, these carbon films offer good prospects for developing elastic coatings with a low coefficient of friction that can be used to produce lubricant-free sliding parts such as dynamic seals. They may also be used in the production of membranes for gas filtration, water desalination or purification, because their pores are similar in size to single molecules.

This story is adapted from material from Drexel University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.