DYNAMIC MONTE-CARLO SIMULATION OF BOMBARDMENT-INDUCED OXYGEN REDISTRIBUTION AT ZRO2 SURFACES

Dynamic Monte Carlo simulation is used to study the influence of the i ncident primary beam energy on oxygen redistribution during the dynami c processes of surface composition changes under He+ and Ar+ bombardme nt of ZrO2 surfaces. The code is developed to describe the effect of t he higher mobility of the light He+ ions during penetration of the tar get. The compositional profiles obtained are related to the ZrO2 surfa ce alteration under the dominating mechanism of oxygen preferential sp uttering for Ar+ bombardment and threshold sputtering with He+ bombard ment. The differences in the O/Zr ratio depth-dependencies for the two cases are discussed. The altered-layer thicknesses are found to be ab out 80 and 150 Angstrom, respectively. (C) 1998 Elsevier Science Ltd. All rights reserved.