  Although theoretical investigations indicate that the successful combination
of graphene and diamond would give interesting properties, only a limited
number of reports dealing with the subject have been published. Here, we
present a rapid thermal process (RTP) which involves Ni as metal catalyst for a
direct growth of graphene on diamond at a temperature of 800 $^{\circ}$C for 1
min. This process operates with a combination of a lower temperature and for a
shorter duration than what has previously been reported. Thin Ni films with
different thicknesses were deposited on top of (100) single crystalline
diamond. After RTP, the coverage of monolayer graphene was found to be around
20% shown by the intensity ratio between the 2D- and G peak using Raman
spectroscopy on 50-nm thick Ni films. In addition, x-ray photoelectron
spectroscopy and atomic force microscopy analysis were conducted for additional
investigation. For electrical characterization, Hall-effect measurements were
performed at temperatures between 80 and 360 K.
