The dynamical behavior of the capacitively coupled argon plasma driven by very high frequency
Abstract
The dynamical behavior of the capacitively coupled Ar plasma driven by four frequencies (54, 80, 94 and 100MHz) at fixed pressure are simulated by the particle-in-cell/Monte-Carlo collisions (PIC/MCC) model based on the electromagnetic field. The magnetic field is generated by plasma current itself. The results show that the electron density, charge density, and electron temperature increase with the frequency increase when radio frequency (RF) power is 40W. The electron heating rate and argon ion heating rate near the sheath increase with the frequency increase. The high-energy electron density ( eV) varies nonlinearly with the frequency increase. The high-energy electron density is highest at 80MHz among the four frequencies. The electron density, charge density, and high-energy electron density increase with RF power (30, 45, 60, and 75W) increase at 80MHz. The electron temperature decreases with RF power increase at 80MHz. The electron heating rate and argon ion heating rate near the sheath have no change with RF power increase at 80MHz. The electron energy probability distributions (EEPF) show that the number of high-energy electrons ( eV) is highest at 80MHz. The reason may be the electron resonant heating that occurs in the plasma when the electron cyclotron frequency equals source frequency at 80MHz. The electron dynamics of capacitively coupled plasma is important for microelectronics etching and membrane deposition.
