AN XPS STUDY OF DIAMOND FILMS GROWN ON DIFFERENTLY PRETREATED SILICON SUBSTRATES

X-ray photoelectron spectroscopy was used to investigate how different pretreatments modify the chemical composition and bonding on silicon substrate surface and, to detect the intermediate phases present at the diamond film interface. The pretreatments were mechanical scratching with a diamond powder, ultrasonic abrasion with diamond suspension and in situ negative dc biasing. The XPS results indicated the presence of hydrocarbons and the formation of new chemical species on the Si substrates such as oxides and carbides. The very important role played by silicon carbide on diamond nucleation and growth was underlined by the phases found at the diamond films interface.