Effect of substrate temperature on hot-filament CVD grown diamond films at constant filament current

This is a systematic study of diamond films grown over silicon substrate by the hot-filament chemical vapour deposition technique at substrate temperatures of 750–50–1,000°C. The resulting films are characterised using the scanning electron microscope, X-ray diffraction and Raman spectroscopy. Our observations are that with the increase in the substrate temperature the morphology of deposited film changed from cauliflower structure to pyramidal featured structure. At substrate temperature of 950°C, planar growth of diamond film was observed, showing good purity crystals. This type of growth has potential for applications where atomically flat surface at localised regions is a prime concern.