| Crystal Research and Technology |
Diamond films of different quality have been synthesized by hot filament chemical vapor deposition (HF CVD) methods from a mixture of hydrogen and hydrocarbon gases. Thin polycrystalline films deposited on silicon substrate were studied using Raman spectroscopy, scanning electron microscopy (SEM) and electron paramagnetic resonance (EPR) technique. Nonuniform distribution of substrate temperatures yields to growth of diamond films in a variety of ways and affects on various types of carbon structures and different kind of defects. The Raman peak shifts to wave number higher than 1332 cm-1 what corresponds to a compressive stress in the range of -0.49 to -1.87 GPa. Two EPR centres with g = 2.003 and Δ Hpp equal to 0.65 and 1.2 mT originate from carbon dangling bonds in diamond and in non-diamond phase, respectively.
Keywords: diamond film, CVD method, Raman spectrum, crystal defects, EPR, SEM