Mechanisms of sputtering of nanoparticles embedded into solid matrix by energetic ion bombardment

• Ion sputtering mechanisms of nanoparticles embedded in solid matrix are presented.
• Sputtering by multicharged ions is based on increase of Coulomb potential energy.
• Modification of thermal spike mechanism for the nanoparticles has been studied.

The mechanisms of sputtering of nanoparticles embedded in the solid matrix under ion bombardment are presented. The mechanism of sputtering by multicharged ions is based on the increase of the potential energy associated with the Coulomb interaction of charges. It is shown that the increase of the lifetimes of holes formed under ionization of the material in the track of the nanoparticles enlarges the sputtering yield due to the confinement of charges. The modification of the thermal spike mechanism has been studied, when the modifying factor is the interface between the nanoparticle and the matrix, which is characterized in the phonon and electron subsystems by the corresponding coefficients of the wave reflection. The process of heat injection into the lattice and following averaging of the probability of atoms' evaporation is described in framework of the two-temperature phenomenology. The expressions for the sputtering yield Y are obtained, which are dependent in all cases on the size of the nanoparticles.