Particle-in-cell simulation of metal plasma flow in dual plasma deposition

Dual plasma deposition is a versatile method of thin film fabrication in which both gaseous and metal plasmas are co-deposited, thus having the advantageous feature of being able to form films of a wide range of elemental and compound composition. However, since the density of the metal plasma formed by a vacuum arc plasma source is non-uniform both radially and axially, the uniformity of the deposited film is in general poor. We have developed a two-dimensional particle-in-cell (PIC) model describing the spatial and temporal evolution of the metal plasma particle density and potential distributions throughout the simulation region. The results indicate that the time required for steady state distributions of density and potential to evolve is determined by the plasma streaming velocity and the axial distance of relevance. The uniformity of the deposited film is improved as the distance from source to substrate is increased. Comparison with experimental results indicates that the simulation model provides a valid description of the metal plasma flow.