One-Dimensional Simulation of Microwave Propagation in Electron Cyclotron Resonance Plasmas

Recently, there have been many efforts in modeling new processing plasma sources such as electron cyclotron resonance (ECR) plasmas, helicon-wave-excited plasmas and inductively coupled plasmas. In the new sources, ECR plasmas are especially difficult to model because of highly nonlinear coupling between microwaves and the magnetized plasma. Accordingly, appropriate modeling of the interactions between the microwave and the magnetized plasma is the key to resolving the problem. In this paper, we present numerical simulations based on a one-dimensional model using the finite-difference time-domain (FDTD) method and discuss the characteristics of the microwave propagation in ECR plasmas. Furthermore, we compare the simulation results with the experimental results by interferometry measurement and show the validity of the model. As a result, it is found that the model proposed here can simulate the qualitative characteristics of the microwave propagation in the plasma, which strongly depend on gas pressure.