Heavy ions irradiations on microelectronic components can lead to different kind of degradations which can be characterized by a raise in the leakage current through the gate oxide. These effects will affect negatively the lifetime and the reliability of the components. The reasons of these effects are the atomic displacements after the impact of the ion. The aim of this thesis is to characterize at the atomic scale using simulation methods as classical molecular dynamics or ab initio molecular dynamics the phenomena of atomic displacements in order to improve the hardening of components under irradiation. In this study, we will treat not only gate oxide materials used in the current transistor generations (SiO2, HfO2) but also the ones that are guessed as the gate oxides for the future generations of components (Al2O3, La2O3). This study will be linked with other simulation levels as Kinetic Monte Carlo and also with experiments.