X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectroscopy (ToF-SIMS) were used to study the chemical composition of SiC crystal surface treated with hydrofluoric acid and oxidized in hydrogen peroxide solutions. The oxidation of the [0 0 0 1] oriented SiC crystals in H2O2 and Watts plating bath was performed at 55 degreesC. The pretreatment of SiC crystals with concentrated HF acid created a layer of CFx species which was relatively resistant to oxidation in H2O2. The SiFx species showed opposite behavior in water solutions, being removed relatively fast from the SiC surface. The results indicate that the fluorinated surface was covered with Teflon-like species relatively resistant to oxidation. (C) 2003 Elsevier Science B.V. All rights reserved.