GROWTH AND MORPHOLOGICAL-CHANGES OF CHEMICALLY VAPOR-DEPOSITED DIAMOND IN THE PRESENCE OF ARGON

Diamond films were produced on Si(100) substrates by decomposing gaseo us mixtures of methane and hydrogen in a low pressure microwave discha rge. The added argon gas can be regarded as an efficient dilution gas although hydrogen is the main dilution gas reacting actively in the di amond deposition. Different ratios of argon gas to methane and hydroge n concentrations have been studied. Scanning electron microscopy, tran smission electron microscopy, X-ray diffraction, electron energy loss spectroscopy and Raman spectroscopy were used to characterize the morp hology, microstructure, composition and crystallinity of the deposited diamond films. Results indicated that the introduction of argon gas e ffectively influenced the growth rate, surface morphology and crystall ine perfection of the diamond deposits at a higher starting concentrat ion of methane which normally yielded high ratios of non-diamond carbo n phases.