Abstract: In an electrostatic chuck, RF bias power is separately applied to a workpiece and to a process kit collar surrounding the workpiece. At least one variable impedance element governed by a system controller adjusts the apportionment of RF bias power between the workpiece and the process kit collar, allowing dynamic adjustment of the plasma sheath electric field at the extreme edge of the workpiece, for optimum electric field uniformity under varying plasma conditions, for example.

Abstract: Embodiments of a method of calculating the equivalent series resistance of a matching network using variable impedance analysis and matching networks analyzed using the same are provided herein. In one embodiment, a method of calculating the equivalent series resistance of a matching network includes the steps of connecting the matching network to a load; measuring an output of the matching network over a range of load impedances; and calculating the equivalent series resistance of the matching network based upon a relationship between the measured output and the load resistance. The load may be a surrogate load or may be a plasma formed in a process chamber.