Deposition of Diamond Film on Aluminum Nitride Ceramics and theStudy of Their Thermal Conductance

Diamond films (DF) have been deposited on AlN ceramic substrates by hot filament chemical vapour deposition method. The diamond nucleation on AlN ceramics has been investigated. A nucleation density more than 10⁸ cm^-2 was obtained on this kind of insulating polycrystalline substrate under common deposition conditions. The thermal conductance of the DF/AlN compound materials has been studied by photothermal deflection technique. The thermal diffusivity of the DF/AlN is higher than that of the AlN ceramics, and will increase as the diamond films grow thicker.