| CPC H01J 37/32183 (2013.01) [C23C 16/50 (2013.01); C23C 16/52 (2013.01); H01L 22/26 (2013.01); H03H 7/40 (2013.01); H03H 11/30 (2013.01); H01J 2237/24564 (2013.01); H01J 2237/332 (2013.01); H01J 2237/334 (2013.01)] | 20 Claims |

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1. An impedance matching network comprising:
an RF input configured to operably couple to an RF source;
an RF output configured to operably couple to a plasma chamber; and
variable capacitors comprising:
a first variable capacitor, a terminal of the first variable capacitor being electrically connected to the RF input; and
a second variable capacitor separate and distinct from the first variable capacitor, a terminal of the second variable capacitor being electrically connected to the RF output;
wherein at least one of the variable capacitors is an electrically variable capacitor that comprises:
a plurality of capacitors operably coupled in parallel, the plurality of capacitors comprising:
fine capacitors increasing in capacitance; and
coarse capacitors having one or more capacitances, wherein each of the one or more capacitances of the coarse capacitors is greater than a greatest individual capacitance of the fine capacitors; and
a plurality of switches, wherein each switch of the plurality of switches is operably coupled with a corresponding capacitor of the plurality of capacitors to switch in or out the corresponding capacitor;
wherein each capacitor of the plurality of capacitors provides a change to a total capacitance of the electronically variable capacitor when the capacitor's corresponding switch switches in or out the capacitor;
wherein a capacitor position for the electronically variable capacitor for enabling an impedance match is determined by a processor using software, the capacitor position indicative of which of the fine capacitors and which of the coarse capacitors to have switched in; and
wherein an impedance match is enabled by directly switching the electronically variable capacitor to the determined capacitor position.
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