SEMIQUANTITATIVE SUBPLANTATION MODEL FOR LOW-ENERGY ION INTERACTIONS WITH SURFACES - I - NOBLE-GAS ION-SURFACE INTERACTIONS

A semiquantitative, phenomenological model for low energy ion interact ions with surfaces is developed. The model represents a generalization of the qualitative subplantation model of Lifshitz et al., Phys. Rev. B 41, 10 468 (1989). A general equation for describing ion solid inte ractions, including film growth processes, is introduced. This model, for the first time, describes the three major contributions to such in teractions, i.e., ion penetration, defect production, and radiation en hanced diffusion, in terms of simple analytical equations. In this fir st article, the basic assumptions of the model are described and the c oncepts are demonstrated for the example of rare gas ion interaction w ith graphite. The model is developed in both a simple static form and a more complex dynamic one, the latter is applicable to ion fluence-de pendent phenomena. The model provides calculated values of experimenta lly observable quantities such as the primary ion concentrations retai ned in the surface and subsurface layers. It also provides estimates o f quantities that are difficult to measure such as penetration thresho lds, displacement thresholds, and diffusion rates. (C) 1998 American V acuum Society.