The Auger electron spectra of thin (3–30 Å) thermal films of SiO2 on Si were measured. Xenon ion sputtering was also used to provide depth profiles of these films. A feature in the Si LVV Auger spectrum previously attributed to intermediate oxidation states of silicon (SiOx) within 1–2 monolayers of the interface was observed. In addition, the presence of a ‘‘near interface SiO2’’ region where the SiO2 spectra are shifted from their thick SiO2 values has been observed. During sputter profiling of 30 Å films these energies shift from positions close to their thick oxide values to values approximately 5 V higher at the interface. These shifts are observed even without sputtering: the 3 Å oxide has a Si KLL peak energy 3.2 V higher than the 30 Å sample, and O KLL peak energy 3.5 V higher, and Si LVV peak 2.0 V higher, after correcting for band bending in the substrate. These shifts can be attributed to a change in the relaxation energy of the oxide whose physical origin is not as yet understood.