A multicomponent network may be added to a transmission line in a high-frequency circuit to transform a first impedance of a downstream circuit element to second impedance that better matches the impedance of an upstream circuit element. The multicomponent network may be added at a distance more than one-quarter wavelength from the downstream circuit element, and can tighten a frequency response of the impedance-transforming circuit to maintain low Q values and low VSWR values over a broad range of frequencies.

A hybrid matching network is suitable for use with a radio frequency transmission system having a fundamental frequency and a terminating impedance. The hybrid matching network includes a first port, a first capacitor coupled between the first port and ground and having a self resonance frequency that provides attenuation of at least a first amount of a second harmonic of the fundamental frequency, an inductor coupled between the first port and ground and having an inductance such that a parallel combination of the first capacitor and the inductor has a resonant frequency at the fundamental frequency, a transmission line segment having a first end coupled to the first port, a second end, having a desired physical length and a desired physical width, and a second port coupled to the second end of the transmission line segment and adapted to be coupled to the terminating impedance.

A termination for a high-frequency transmission line includes a first resistor that has a first terminal coupled to a first end of a transmission line and a second terminal coupled to a first input/output pad, and a second resistor that has a first terminal coupled to the first input/output pad. The first resistor and the second resistor may provide a combined resistance that matches a nominal value of a characteristic impedance of the transmission line. The apparatus may include a third resistor having a first terminal coupled to a second end of a transmission line, and a second terminal coupled to a second input/output pad, and a fourth resistor having a first terminal coupled to the second input/output pad. The third resistor and the fourth resistor may provide a combined resistance that matches the nominal value of the characteristic impedance of the transmission line.

There is disclosed a multi-band reconfigurable antenna device having at least one radiating element. The radiating element is connected to a single port by way of at least first and second matching circuits arranged in parallel. A high pass filter is provided between the first matching circuit and the radiating element so as to allow passage of a first, higher frequency RF signal through the first matching circuit. A low pass filter is provided between the second matching circuit and the at least one radiating element so as to allow passage of a second, lower frequency RF signal through the second matching circuit. The high pass filter blocks passage of the second, lower frequency RF signal through the first matching circuit, and the low pass filter blocks passage of the first, higher frequency RF signal through the second matching circuit. The first and second matching circuits are adjustable independently of each other so as to allow the first and second RF signals to be tuned independently of each other.

A radio-frequency switching apparatus that can be used to turn a signal path on or off or to attenuate a radio-frequency signal. The switching apparatus comprises at least one radio-frequency input, at least one radio-frequency output, at least one transmission line providing a signal path between the at least one radio-frequency input and the at least one radio-frequency output, and at least one transition metal oxide portion. The radio-frequency switching apparatus also comprises direct current blocking means electrically coupled between the at least one transition metal portion and the at least one radio-frequency input. The radio-frequency switching apparatus also comprises biasing means for providing a bias across the at least one transition metal oxide portion such that power transferred between the radio-frequency input and the radio-frequency output is controlled by controlling the bias level across the at least one transition metal oxide portion.

Embodiments of a circuit, system, and method are disclosed. In an embodiment, a circuit includes first and second microstrip transmission lines. The first and second microstrip transmission lines include linearly arranged conductive strips on the circuit and a slotline formation extends between the first microstrip transmission line and the second microstrip transmission line so that the slotline formation is configured to electromagnetically couple the first microstrip transmission line to the second microstrip transmission line during operation of the circuit. In addition, the circuit includes at least one controllable capacitance circuit electrically connected to at least one of the first microstrip transmission line and the second microstrip transmission line, where a magnitude of a capacitance value of the at least one controllable capacitance circuit (e.g., including a barium strontium titanate (BST) capacitor) is controllable (e.g., in response to a capacitance control signal received at a control interface).

A system, having: an RF power source; an RF matching network electrically coupled to the RF power source; an impedance matching circuit electrically coupled to the RF matching network, wherein the impedance matching circuit has a first adjustable capacitor connected in series with the RF matching network and a second adjustable capacitor connected in parallel with the first capacitor; and an inductive process load electrically coupled to the impedance matching circuit.

Baluns with integrated matching networks are provided herein. In certain embodiments, a balun structure includes a first pair of coupled lines, a second pair of coupled lines and a transmission line. Additionally, a first port of the balun is connected to a reference voltage by way of a first line of the first pair of coupled lines, the transmission line, and a first line of the second pair of coupled lines. Furthermore, a second port of the balun is connected to the reference voltage by way of a second line of the first pair of coupled lines, while a third port of the balun is connected to the reference voltage by way of a second line of the second pair of coupled lines. The first port serves as an unbalanced signal terminal, while the second port and the third port serve as positive and negative signal terminals.

In one embodiment, an RF impedance matching network for a plasma chamber is disclosed. The matching network includes an electronically variable capacitor (EVC) comprising discrete capacitors, each discrete capacitor having a corresponding switching circuit for switching in and out the discrete capacitor to alter a total capacitance of the EVC. Each switching circuit includes a diode operably coupled to the discrete capacitor to cause the switching in and out of the discrete capacitor, and a filter circuit parallel to the diode, the filter comprising a filtering capacitor in series with an inductor.

In one embodiment, an impedance matching network includes a mechanically variable capacitor (MVC), a second variable capacitor, and a control circuit. The control circuit carries out a first process of determining a second variable capacitor configuration for reducing a reflected power at the RF source output, and altering the second variable capacitor to the second variable capacitor configuration. The control circuit also carries out a second process of determining an RF source frequency, and, upon determining that the RF source frequency is outside, at a minimum, or at a maximum of a predetermined frequency range, determining a new MVC configuration to cause the RF source frequency, according to an RF source frequency tuning process, to be altered to be within or closer to the predetermined frequency range. The determination of the new MVC configuration is based on the RF source frequency and the predetermined frequency range.