[en] Commercial power MOSFET (A, B and C) oxides have been characterized by irradiation and isochronal annealing. Low dose irradiation (100 krad(SiO₂) under positive and negative bias shows a uniform oxide charge trapping for the two unhardened devices and an interfacial oxide trap distribution in the case of the rad-hard device. High dose irradiation (10 Mrad(SiO₂) under high negative bias demonstrates the build-up of an electron trapped charge for device A and the conduction at high dose of a parasitic transistor for device B. Irradiation up to 100 krad(SiO₂) and isochronal annealing under positive bias is carried out to compare the spectral distribution of oxide traps between device A oxide and reference buried oxides (SIMOX and UNIBOND). Despite a similar trapping behavior, their spectral distributions are different. Device A presents a lower energy distribution than buried oxides. (authors)