The oxidation of terbium silicide

TbSi 1.7 was grown on Si(100) and on amorphous Si. After these samples were oxidized at 450°C for 90 min, 600°C for 30 min and 800°C for 30 min at atmospheric pressure, Auger depth profiles for all the samples were measured. These profiles indicate that Tb segregated to the surface. Auger spectra show that Tb and not Si is oxidized. During room temperature oxidation of TbSi 1.7 in the vacuum system, the initial oxidation of TbSi 1.7 also shows an enrichment of Tb on the surface, and that Tb as well as Si are oxidized.