Reliability study on high thermally conductive graphene film as heat spreader in electronics cooling applications

Graphene films (GFs) were fabricated and can be applied for dissipating heat from electronics such as portable electronics, laptops, light emitting diodes (LEDs) and other power electronics. These GFs are capable of transporting heat from electronic components. Due to its high thermal conductivity, these GFs are capable to transfer the heat efficiently from electronic component to the heat spreader or heat sink. The cooling failure of the GFs may lead to irreversible damage to the electronic system, hence it is necessary to investigate the long-term reliability of the film under certain harsh conditions. To evaluate the reliability of the GFs, the thermal cycles and moisture test are performed. The effect of temperature cycling (500 cycle) is tested by using an environmental oven with extreme temperatures. The effect of moisture penetration of the GFs is tested for 1024 hours. The thermal conductivity after these two test conditions does not change too much comparing to material before subjecting to test. The electrical conductivity value under the temperature cycling declined by 30% after 500 cycles and that of moisture test was improved by 20%. The result shows that the thermal conductivity of the GFs is quite stable under temperature cycle (500 cycles) and moisture test (1024 hours).