Thermal Management of High-Power Switching Transistors Using Thick CVD-Grown Graphene Nanomaterial

Graphene is a promising material for thermal management. Heating in power electronics is a severe issue since heat generation can lead to rise in device temperature which can cause performance degradation and device failure. However, current approaches are not so efficient because of the extremely small thermal mass of monolayer or few layers graphene. Here we show a new type of chemical vapor deposition (CVD)-grown thick graphene network with in-plane thermal conductivity of 1100 W/mK on ceramic substrates for thermal management of power switching devices. The demonstration of graphene network's thermal management capabilitieswas carried out on a 10-Oresistor module and a 1.2-kV SiC MOSFET package module. The results show that the thermal management performance using graphene coated on a low cost Al2O3 direct-bonded copper (DBC) is significantly superior to the industry standard, costlier AlN DBC substrates. Specifically, the temperature of hot spots is lower by at least 25 degrees C when using CVD-grown graphene networks for thermal management. Numerical simulations suggest that the high in-plane thermal conductivity of thick graphene networks helps in quick transfer of heat away from the device. These demonstrations represent a transformative change on thermal management of WBG high-power switching devices.