THERMAL-DIFFUSIVITY OF DIAMOND FILMS WITH SUBSTRATES

Diamond films were prepared by hot-filament chemical vapour deposition system. Photothermal deflection technique has been used to measure th ermal diffusivity of diamond films with substrates. The influence of s ilicon or quartz substrate on the measurement of thermal diffusivity o f film is presented. A simple two-layer model has been given to explai n the effect of substrates on the measurement of thermal diffusivity a nd used to draw thermal diffusivity of diamond film from effective the rmal diffusivity of film/substrate system.