CHEMICAL-VAPOR-DEPOSITED DIAMOND FOR THERMAL MANAGEMENT

The record-high thermal conductivity of high-quality diamond makes it a natural choice for many applications in thermal management. The colu mnar microstructure of chemical-vapor-deposited diamond thick films, h owever, causes anisotropy and a strong gradient in the conductivity, b oth of which can be understood in terms of phonon-scattering defects t hat aggregate near grain boundaries. Techniques to take maximum advant age of the high thermal conductivity include the removal of fine-grain ed low-conductivity material near the substrate surface and the provis ion of excellent thermal contact between the diamond and heat sources or sinks.