Diamond films have been synthesized on the adamantane-coated Si (1 0 0) substrate by microwave plasma chemical vapor deposition from a gaseous mixture of methane and hydrogen gases with a growth rate of ∼6.7 nm/min. The substrate temperature was ∼475 °C during diamond deposition. The films obtained have good crystallinity that is characterized by scanning electron microscopy and Raman spectrometry. X-ray photoelectron spectroscopy analysis has confirmed that diamond nucleation and growth are on SiC rather than clean Si. The possible mechanism of high rate growth diamond films has been demonstrated.