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

Diamond films were produced on Si(100) substrates by decomposing gaseous mixtures of methane and hydrogen in a low pressure microwave discharge. The added argon gas can be regarded as an efficient dilution gas although hydrogen is the main dilution gas reacting actively in the diamond deposition. Different ratios of argon gas to methane and hydrogen concentrations have been studied. Scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electron energy loss spectroscopy and Raman spectroscopy were used to characterize the morphology, microstructure, composition and crystallinity of the deposited diamond films. Results indicated that the introduction of argon gas effectively influenced the growth rate, surface morphology and crystalline perfection of the diamond deposits at a higher starting concentration of methane which normally yielded high ratios of non-diamond carbon phases.