Patent attributes
An RF impedance matching network includes an RF input configured to operably couple to an RF source, the RF source having a fixed RF source impedance; an RF output configured to operably couple to a plasma chamber, the plasma chamber having a variable plasma impedance; a series EVC; a shunt EVC; an RF input sensor; and a control circuit configured to: determine an input impedance; determine the plasma impedance; determine a first capacitance value for the series variable capacitance and a second capacitance value for the shunt variable capacitance, the determination of the first capacitance value and the second capacitance value based on the plasma impedance and the RF source impedance; generate a control signal to alter at least one of the series variable capacitance and the shunt variable capacitance to the first capacitance value and the second capacitance value, respectively.