Refined “statistical” model of secondary ion formation

A model of formation of secondary ion during ion-beam sputtering of a target is considered. The model is based on the so-called “statistical model” of formation of secondary ions at a certain critical distance from the surface, which was proposed earlier. The concept of dynamic temperature introduced in earlier publications for a cascade of collisions initiated by a primary ion, as well as a new interpretation of the interaction of the formed ion with the surface charge of opposite polarity, enabled us to derive an analytic expression for the ion formation probability. Comparison of the results of calculation with experimental data shows good agreement testifying the correctness of the proposed model.