Image forces and the behavior of mobile positive ions in silicon dioxide

The electrostatic image force has important effects on the behavior of ions located near an interface. In metallized thin films of SiO2 on silicon the attractive image potential depletes ions from the bulk and localizes them near the interfaces with metal or silicon. For ions localized near the silicon interface, it is shown that a uniform lateral distribution of ions is inherently unstable and tends to condense into patches of high concentration.