AVS 47th International Symposium
    Surface Engineering Tuesday Sessions
       Session SE-TuP

Paper SE-TuP10
Formation and Dynamic of Nuclei Distribution Function in Ion Deposition. Theoretical and Numerical Investigation

Tuesday, October 3, 2000, 5:30 pm, Room Exhibit Hall C & D

Session: Poster Session
Presenter: I.G. Levchenko, Kharkov State Aerospace University, Ukraine
Authors: I.G. Levchenko, Kharkov State Aerospace University, Ukraine
M. Keidar, University of Michigan
Correspondent: Click to Email
The defining role of nuclei distribution function in thin film structure formation is now proved. The present paper is intended to develop the complete model of distribution function formation covering the whole set of the most important factors influencing the film growth. In particular, the following processes were taken into account: adsorbed particles diffusion about the substrate surface; nucleus diffusion causing the distribution function change; nuclei collisions; nuclei coalescence accompanied with the transitional quasi-liquid layer formation; etc. The study was carried out on the basis of the continuity equation for nucleus distribution function and equation for adatoms concentration in the nucleus area. Dynamic of distribution function formation was studied in the various conditions of deposition namely in high and low external flow intensity, high and low diffusion mobility, etc. The numerical simulation was performed using the above model in the most complex conditions: high rate of adsorbed particles and nuclei migration, high intensity of external flow, high substrate temperature, various ionization coefficients. The program developed provides both distribution function calculation and surface ensemble visualization in the form of series of the screen shots. The nuclei ensemble consisting 1000 particles was investigated, and surface concentration fields were calculated in the area of non-continuous film being formed. Comparisons with experimental data are shown justifying the accuracy of the model proposed.