Graphene-based film quadruples speed of electronics cooling
Fri 10 Jul 2015
Researchers are developing a technology which is able to cool electronic devices using graphene film.
The team of scientists from Chalmers University of Technology has designed the graphene-based film which has four times the thermal conductivity capacity of copper. With an ever increasing demand for computing performance, electrical components generate a large amount of heat and the accumulated waste must be got rid of efficiently to prolong the device’s lifespan, and reduce energy usage.
The Chalmers University researchers, led by Professor Johan Liu, have found that graphene has a cooling effect on silicon-based electronic equipment.
“The methods that have been in place so far have presented the researchers with problems,” said Liu. “It has become evident that those methods cannot be used to rid electronic devices off great amounts of heat, because they have consisted only of a few layers of thermal conductive atoms. When you try to add more layers of graphene, another problem arises, a problem with adhesiveness. After having increased the amount of layers, the graphene no longer will adhere to the surface since the adhesion is held together only by weak van der Waals bonds,” he explained.
“We have now solved this problem by managing to create strong covalent bonds between the graphene film and the surface, which is an electronic component made of silicon,” Liu added.
The stronger bonds were created by adding a property-altering molecule to the graphene. The team had tested several of these functionalising additives and found that the most effective addition was (3-Aminopropyl) triethoxysilane (APTES) molecules. Once heated and hydrolysis, silane coupling is created between the graphene and the electronic device.
This silane bonding process is also said to double the thermal conductivity of the graphene. The Chalmers scientists showed that the 20-micrometre thick graphene-based film could reach a thermal conductivity value of 1,600W/mK – four times greater than copper’s capacity.
“Increased thermal capacity could lead to several new applications for graphene,” suggested Liu.
He concluded: “One example is the integration of graphene-based film into microelectronic devices and systems, such as highly efficient Light Emitting Diodes (LEDs), lasers and radio frequency components for cooling purposes. Graphene-based film could also pave the way for faster, smaller, more energy efficient, sustainable high power electronics.”