ANALYSIS OF THE FINE-STRUCTURE OF THE RAMAN LINE AND OF X-RAY REFLECTION PROFILES FOR TEXTURED CVD DIAMOND FILMS

Textured diamond films prepared by CVD were studied by X-ray measureme nts and Raman spectroscopy in the high dispersive mode in order to get structural information. A [100] fibre texture is observed for the fil ms prepared with a 2% methane concentration and a low substrate temper ature. For all the 2% CH4 samples the diffraction spectra reveal an im portant broadening of the 111 reflection and two additional bands at a bout 0.207 and 0.217 nm attributed to stacking faults along the [111] direction. Domains of hexagonal symmetry can then locally be formed wi th the defect ordering. The recording of a 1322 cm(-1) Raman line gene rally attributed to the lonsdaleite or hexagonal diamond polytypes sup ports this assumption. This [100] fibre texture is recorded for sample s obtained with a high methane concentration (2%) related to a fast gr owth rate, which may explain these stacking faults along the [111] dir ection.