The anodic oxidation of the silicides CoSi, CoSi 2, CrSi 2, Ni 2Si, NiSi, NiSi 2, Pd 2Si, PtSi, TiSi 2 and ZrSi 2 was studied by using Rutherford backscattering of 2MeV alpha particles. The room temperature oxidation was carried out at a constant current density of 8.9 mA cm -2 using n-methylacetamide (2% H 20 and 1% KNO 3) as electrolyte. No oxidation of Pd 2Si and PtSi was detected. Pure SiO 2 layers were grown on CoSi, CoSi 2, Ni 2Si, NiSi and NiSi 2 at a much lower rate than on Si<100> and with a thickness increase per volt of 0.6 ± 0.03 nm V -1. Mixed layers of SiO 2/metal oxide were grown on CrSi 2, TiSi 2 and CrSi 2. All oxidations occurred at the expense of the silicide layer. It is also shown how the purity of the SiO 2 layer formed can be predicted from thermodynamic considerations.