(56a) Past and Future of Modeling and Simulation for Plasma Processing

A pervasive feature of plasma processing is the great disparity of length and time scales that must be treated. Length scales range from the reactor (10s of cm), to the sheath (100s of microns), to the surface features (nm), to the lattice spacing (Angstroms). Time scales range from events happening on the surface right after ion bombardment (ps), to the plasma frequency (ns), to the gas residence time (10s of ms), to surface profile evolution (min). Judicious approximations must be made to ?separate? these disparate processes. At the same time, intimate ?two-way? coupling among some of these processes can make the problem extremely complicated.

Over the past 25 years, plasma reactor modeling and simulation has evolved from low-dimensional (0-D and 1-D) models with almost no chemistry, to full 3-D simulations including electromagnetics and fairly realistic chemistries. Similarly, feature profile evolution simulations have progressed from the rather primitive ?string model? to full 3-D Monte Carlo-based simulations. At the same time, molecular simulations (primarily Molecular Dynamics) have provided a wealth of information on surface processes influenced by energetic ion bombardment.

This paper will review the progress made in modeling and simulation of plasma processes over the years and discuss the challenges that are facing the field moving forward.