Growth of diamond films on silicon via hot filament chemical vapor deposition

Diamond films were achieved on Si (100) substrates via hot filament chemical vapor deposition (HFCVD). The films were characterized by Scanning Electron Microscopy (SEM), Raman Spectroscopy (RS) and X-ray diffraction (XRD). The HFCVD processes were performed under standard conditions. The substrate temperature was set between 700 and 900 Centigrade by using a substrate heater. The filament temperature was kept between 2000-2150 Centigrade, the process pressure was varied from 28.8 to 32 Torr. The gas mixture consisted of 0.25 to 4.00 sccm methane, and 205 to 250 sccm hydrogen. The presence of the characteristic narrow first order Raman line at 1332 cm is roof that more than 90 % of the film consists of diamond crystals. RS is the most sensitive method to determine the presence in the diamond film of non-diamond forms of carbon. Utlizing X-ray diffraction (XRD), we present results for the relative intensities of the XRD, we present results for the relative intensities of the XRD peaks originating from the (111), (220), (400) crystallographic planes as functions of CH4/H2 make up during growth. SEM observations substantive these results. The well faceted cubo-octahedral crystal and ball-like structures were found under different conditions. (Author)