Stability of metal nanocomposites under heavy-ion bombardment of insulators

Optical transmission and ion-induced photon emission of SiO2 (silica glass), LiNbO3 and Al2O3 were measured during implantation of 60-keV Cu− or Au− ions. Conditions of stability of metal nanocomposites were determined and represented with the help of nonequilibrium phase diagrams. Formation of structures dynamically stable under ion bombardment diminished the efficiency of ion implantation for further accumulation of implants as in nanoparticles. Contributions from various radiation-induced processes (sputtering, radiation-induced diffusion, atomic collisions, electronic excitations, etc.) to formation of nanocomposites were evaluated.