Abstract: An apparatus for matching the variable impedance of a load with the fixed impedance of a radio frequency (RF) power generator to provide maximum power transfer. The impedance matching network further allows an RF power generator to vary the frequency of the voltage applied to a load, e.g., a plasma chamber as may be utilized in semiconductor or flat panel plasma display manufacturing processes. The impedance matching network further utilizes fixed solid state components to adjust the impedance of the attached load to provide maximum power transfer between the generator and the load. A parallel switched capacitor network is controlled by an electrical switching means such as PIN diodes to turn fixed capacitors on or off. A means for varying the frequency of the applied voltage is used to match the impedance of the load with the impedance of the RF power generator within milliseconds.

Abstract: A two-cavity notch filter including an input terminal inductively coupled to an output terminal having a low impedance connection therebetween, a first relatively high impedance resonant tank circuit including the series combination of a circuit grounded capacitor and circuit grounded inductor having a tap point thereon, a capacitor and optionally in series therewith an inductor connected between the input terminal and tap point. The notch filter also includes a second relatively high impedance resonant tank circuit including the series connection of a circuit grounded capacitor and circuit grounded inductor having a tap thereon, and a capacitor and, optionally, in series therewith an inductor between the output terminal and tap point of the second tank circuit inductor. There is capacitive coupling between the capacitors forming the first and second tank circuits.