Peculiarities of Interaction of Low-Energy Noble Gas Atoms with Methyl Groups on the Low-K-Surface

In the current work the computer simulations were performed to study the possibility of surface functionalization of low-K materials that are used as interlayer insulators within ultralarge integration devices with low-energy (up to 30 eV) noble gas atoms. The simulations were carried out using the ab initio density functional theory method assisted with molecular dynamics algorithms implemented in VASP package. The detailed trajectory analysis revealed the conditions under which the irradiation of incident He, Ne, Ar, Xe atoms with the energy up to 30 eV may result in the illumination of near-surface methyl groups responsible for hydrophobic properties of dielectric surface. Based on the data obtained the threshold energy (the minimum atom energy for CH₃-radical formation) was evaluated, and the mechanism peculiarities of such a process under light and heavy atom irradiation were studied. It was shown that in the energy range under consideration the interaction Ne, Ar, and Xe with methyl groups has mainly collisional mechanism, therefore with increase in mass of the incident particle the threshold energy increases. He atom irradiation, on the contrary, is capable to induce the perturbations of the electronic density around the methyl group that stimulate fast atom vibrations and result in CH₃-detachment.