Diffuse reflectance Fourier-transform infrared study of the plasma-fluorination of diamond surfaces using a microwave discharge in CF4

Species chemisorbed on diamond surfaces, which had been treated under CF4-plasma conditions, have been investigated by diffuse reflectance Fourier-transform infrared spectroscopy. Both oxidized and hydrogenated diamond surfaces were fluorinated at temperatures in the range 300–1000 °C. The C—F bond was observed on the diamond surfaces. No fluorination was observed after thermal treatment only in a CF4 environment. Plasma conditions were essential for fluorination using CF4 as reactant precursor. We also observed that the surface reaction temperature is the most important factor, particularly for the fluorination of oxidized diamond. Fluorination of hydrogenated diamond surfaces proceeds at lower temperatures than that of oxidized diamond surfaces.