Multi-scale simulation of plasma generation and film deposition in a circular type DC magnetron sputtering system

Abstract

We present a computational study on the plasma generation and film deposition in a circular type DC magnetron sputtering system. Design optimization of a large-area magnetron sputtering system needs a precise multi-scale simulation considering a target erosion by magnetron plasma, a macrofilm deposition by collisional transport, and a micro-deposition topography by collisionless transport. Our multi-scale simulation consists of particle-in-cell and Monte Carlo collision method (PIC-MCC) magnetron plasma simulation and Monte Carlo macro/microfilm deposition simulation. Thompson energy distribution and cosine angular distribution are used for the kinetic energy distribution and for the angular flux distribution of the sputtered atoms, respectively. A variable hard sphere (VHS) model is used to calculate the collision cross section of sputtered atoms and an equi-volume rate model (EVRM) is used to represent evolving film surface.The target erosion profiles are expected from the ion current density distribution on the sputter target simulated by two-dimensional PIC-MCC magnetron plasma simulator, and these profiles are compared with the experimental results. We present a discussion about the optimum detection range for the quasi-steady state of magnetron plasma in PIC-MCC simulation. Macro/microfilm deposition simulator predicts the macrofilm uniformity over the wafer and the micro-deposition topography in the micro-holes. Finally, we present a new algorithm, which can generate an asymmetric angular flux distribution, based on Monte Carlo method for microfilm deposition simulation.