RAMAN AND X-RAY STUDIES OF POLYCRYSTALLINE CVD DIAMOND FILMS

Differently prepared microwave plasma-deposited diamond films with a b road spectrum of morphological and Raman spectroscopic features were i nvestigated by scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction (XRD). XRD indicates the presence of graphitic p olytypes in most samples, independent of growth conditions or morpholo gy. X-ray texture analysis reveals pronounced fibre textures not only for well-faceted deposits, but also for smooth, fine grain films. Info rmation about internal strain, stacking faults and average crystallite sizes is obtained from diffraction peak shifts and widths. Crystallit e sizes deduced from XRD profiles are found to be orders of magnitudes smaller than the grain sizes observed by SEM. An analysis of the diam ond Raman peak position, width and shape suggests that Raman peak broa dening is dominated by phonon lifetime reduction. Raman and X-ray diff raction data reveal a reciprocal relationship between the width of the diamond Raman line and the crystallite size.