A thin film insulating SiO₂ was prepared using a laser oxidation technique. The growth of the dioxide layers and the interface Si/SiO2 were studied by analyzing the absorption spectrum through an FT-IR spectrometer. The results show a characteristic sharp peak at the wave number (1079 cm^-1) corresponds to the level of elongate ion vibrations (Si-O-Si) which consists of required oxide. The shoulder region appeared at the wave number (1200 cm^-1) which indicates that the silicon atom was moving in the opposite direction of an oxygen atom. The increase in temperature leads to reducing the absence of the entropy in the composition of SiO₂. The different times for the oxide configuration give a different value for the capacity where the highest capacity was created for the longest time, that the oxide thickness has an inverse relationship with the time of laser induction of the oxidation.