Effect of Magnetization on Impedance Characteristics of a Capacitive Discharge Using Push-Pull Driven Cylindrical Electrodes

The impedance characteristics of a 13.56-MHz capacitively driven, symmetric magnetized discharge, created in argon and helium using an array of cylindrical electrodes, are presented. It is found that the discharge produced in argon is largely capacitive, while it tends to becoming inductive as the axial magnetic field strength increases. However, an opposing trend is seen in the case of helium discharge. On the other hand, the effective resistance is seen to continuously decrease for both helium as well as argon. The effect of increasing the radio frequency (RF) power levels is seen to have a marginal effect in the plasma density formed between the discharge electrodes, whereas the density rise is quite significant with the increase in the magnetic field. This behavior has been attributed to power mode transition from ion to electron heating inside the discharge.