POWER DEPOSITION IN HIGH-DENSITY INDUCTIVELY-COUPLED PLASMA TOOLS FOR SEMICONDUCTOR PROCESSING

A two-dimensional, computationally efficient numerical model is developed to study power deposition in high-density inductively coupled plasma sources. Calculations include both inductive coupling, caused by plasma response to external coil currents, and capacitive coupling, caused by plasma response to external voltages on the coils and wafer. Variation in current along the induction coil is determined self-consistently from the integral constraint of charge conservation. Sheath phenomena are incorporated through previously published analytic models. The system behavior is analogous in some respects to that of a transmission line. Comparison with measurement suggests that this model provides a good description of self-consistent coil response when the electric field exhibits less than a quarter wavelength per coil turn. © 1995 American Institute of Physics.