X-ray diffraction measurement and raman spectroscopy of chemical vapor deposited diamond films

Chemical Vapor Deposited (CVD) diamond is synthetic diamond fabricated from the gas phase at relatively low temperatures and pressures. The main attraction of CVD diamond is the fact that it is in film form. With its many extreme properties diamond in film form opens up many possible industrial applications such as mechanical and optical coating, heat spreaders, electron emitters and specialized microelectronics components. In most of these applications the quality of the deposited diamond is crucial and it is well known that both diamond and non-diamond carbon is formed simultaneously during the deposition process. We have applied Raman Spectroscopy and X-Ray Diffraction techniques to study diamond films deposited on Si (100) using a microwave plasma system at different substrate temperatures. Diamond films were deposited on Si (100) using methane diluted in hydrogen. Raman shift measurements were used to monitor the presence of both diamond and non-diamond carbon phases in the films. It was found that the quality of the diamond films showed a marked increase in quality with increasing substrate temperature. XRD measurements revealed that the films were polycrystalline, with preference to the D(111) plane. Particles size analysis based on the XRD measurements showed that the diamond particles were made up of smaller particles. Both XRD and Raman spectroscopic measurement showed that the films were under compressive stress. (Author)