A group of researchers at the University of California, Riverside Bourns College of Engineering have developed a technique to keep cool a semiconductor material used in everything from traffic lights to electric cars.
Gallium Nitride (GaN), a semiconductor material found in bright lights since the 1990s, is used in wireless applications due to its high efficiency and high voltage operation. However, the applications and market share of GaN electronics is limited because it is difficult to remove heat from them.
The Nano-Device Laboratory research group designed and built graphene-graphite “quilts” on top of GaN transistors. The graphene-graphite quilts’ function was to remove and spread the heat from the hot spots – the opposite of what you expect from the conventional quilts.
Using micro-Raman spectroscopic thermometry the researchers demonstrated that temperature of the hot spots can be lowered by as much 20 degrees Celsius in transistors operating at the large power levels.