  Boron-doped single crystal diamond films were grown homoepitaxially on
synthetic (100) Type Ib diamond substrates using microwave plasma assisted
chemical vapor deposition. A modification in surface morphology of the film
with increasing boron concentration in the plasma has been observed using
atomic force microscopy. Use of nitrogen during boron doping has been found to
improve the surface morphology and the growth rate of films but it lowers the
electrical conductivity of the film. The Raman spectra indicated a zone center
optical phonon mode along with a few additional bands at the lower wavenumber
regions. The change in the peak profile of the zone center optical phonon mode
and its downshift were observed with the increasing boron content in the film.
However, shrinkage and upshift of Raman line was observed in the film that was
grown in presence of nitrogen along with diborane in process gas.
