DIAMOND CHEMICAL-VAPOR-DEPOSITION USING TANTALUM FILAMENTS IN H2-CH4-O2 GAS-MIXTURES

Diamond films were deposited onto different substrates, mainly silicon and molybdenum. High growth rates of up to 16 mum h-1 were achieved at filament temperatures of 2600-degrees-C. The influence of oxygen on the deposition process, especially on the filament activity and growth rate, was investigated. Owing to the high filament temperature, comparatively high methane concentrations of more than 10% could be used without the addition of oxygen, and the addition of oxygen allowed the methane concentration to be increased up to 16%. The films were of good quality, as observed by Raman spectroscopy. Highly textured films were deposited onto silicon at the highest growth rates.