Abstract
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.