Self-Consistent Particle Modeling of Inductively Coupled CF4 Plasmas: Effect of Wafer Biasing

Abstract

The structure of axisymmetrical inductively coupled CF4 plasmas with wafer biasing was examined by the particle-in-cell/Monte Carlo method. The simulation was performed under the conditions that gas pressure is fixed at 5 mTorr and power deposition is fixed at 200 W. The effect of biasing frequency on plasma structure and the energy of the ions that were incident on the wafer was examined. The biasing frequency was changed from 0.8 to 25 MHz. Biasing frequency affects the plasma structure. Ion energy distribution strongly depends on biasing frequency and ion mass, namely, the ratio of ion transit time across the sheath to rf period. These results are consistent with previous measurements.