Electron paramagnetic resonance characterization of diamond films fabricated with different methane concentrations

Electron paramagnetic resonance (EPR) studies were performed on thin diamond films fabricated by hot‐filament chemical vapor deposition using methane concentrations varying from 0.25% to 5%. The bulk spin concentration and the peak to peak linewidth for the characteristic g=2.0027(2) EPR spectrum were found to increase for samples grown with increased methane concentration. The results show the spectrum contains component/s due to paramagnetic defects related to nondiamond carbon phases within the films.