Reno Technologies, Inc.

Advanced Energy Industries, Inc.

Asm America, Inc.

Avitar, Inc.

Advanced Energy's Voorhees Operations

Anton Mavretic

Ian M Costanzo

Ronald Anthony Decker

Theresa Beizer

Frederick Hauer

Imran Ahmed Bhutta

Joseph Osselburn

Tomislav Lozic

In one embodiment, an impedance matching network includes a variable reactance circuit having fixed reactance components and corresponding switching circuits. Each switching circuit includes a diode and a driver circuit. The driver circuit includes, coupled in series, a biasing current source positioned to provide a bias current to bias the diode, a first switch, a second switch, and a resistor. For each diode of each switching circuit, the control circuit is configured to receive a value related to a voltage drop on the resistor and, based on the value related to the voltage drop, adjust the bias current being provided by the biasing current source.

Switching circuit

In one embodiment, an impedance matching network includes a variable reactance circuit providing a variable capacitance or inductance. The variable reactance circuit includes reactance components and corresponding switching circuits. Each of the switching circuits includes a diode and a driver circuit to switch the diode. The driver circuit includes first and second switches coupled in series. A first driver is coupled to the first switch, a second driver is coupled to the second switch, and a third driver is coupled to the first and second drivers. The third driver provides a first signal to the first driver, and a second signal to the second driver. In providing the signals, the third driver increases and decreases a duration of a dead time between (a) driving the first driver on and the second driver off, or (b) driving the second driver on and the first driver off.

In one embodiment, an RF power amplifier includes a first transistor and a second transistor in parallel, wherein a gate of the first transistor and a gate of the second transistor are configured to be driven by an RF source. A third transistor comprising a drain is operably coupled to both a source of the first transistor and a source of the second transistor. A control circuit is operably coupled to a gate of the third transistor and configured to alter a gate-to-source voltage of the third transistor, thereby altering a drain current of each of the first transistor and the second transistor, thereby altering an output power of the RF power amplifier.

RF power amplifier

In one embodiment, an impedance matching network includes an electronically variable reactance element (EVRE) comprising discrete reactance elements and corresponding switches. The switches are configured to switch in and out the discrete reactance elements to alter a total reactance provided by the EVRE. A monitoring circuit is operably coupled to the EVRE. For each discrete reactance element, the monitoring circuit monitors a value related to the discrete reactance element or its corresponding switch. Upon determining the monitored value exceeds a predetermined amount, the monitoring circuit the discrete reactance element of the EVRE from switching in or out.

RF impedance matching network

In one embodiment, an impedance matching network includes at least one electronically variable capacitor (EVC), each EVC comprising discrete capacitors having corresponding switches, the switches configured to switch in and out the discrete capacitors to alter a total capacitance of the EVC. Each switch includes a first terminal operably coupled to the corresponding discrete capacitor, a second terminal, and a switching circuit coupled between the first terminal and the second terminal, the switching circuit comprising a switching transistor. A tuning inductor is coupled parallel to the switching circuit. A value for the tuning inductor enables the tuning inductor to cancel a cumulative parasitic capacitance of the switching circuit.

In one embodiment, a parasitic capacitance compensation circuit for a switch is disclosed that includes a first inductor operably coupled between a first terminal and a second terminal, and a second inductor operably coupled between the first and second terminals and parallel to the first inductor. The second inductor is switched in when a peak voltage on the first and second terminals falls below a first voltage. The first inductance tunes out substantially all of a parasitic capacitance of the switch when the switch is OFF and the peak voltage is above the first voltage. The first and second inductances collectively tune out substantially all of the parasitic capacitance of the switch when the switch is OFF and the peak voltage is below the first voltage.

Parasitic capacitance compensation circuit

In one embodiment, an impedance matching network is disclosed that includes a first circuit comprising a first variable component providing a first variable capacitance or inductance, and a second circuit comprising a second variable component providing a second variable capacitance or inductance. Each of the first circuit and the second circuit includes plurality of switching circuits configured to provide the first variable capacitance or inductance and the second variable capacitance or inductance. Each of the plurality of switching circuits includes a diode and a driver circuit configured to switch the diode. The driver circuit includes a first switch, a second switch coupled in series with the first switch, and a filter circuit that is coupled at a first end between the first switch and the second switch, and is operably coupled at a second end to the diode.

In one embodiment, a switching circuit includes a first switch coupled to a first switch terminal, the first switch comprising at least one gallium nitride high-electron mobility transistor (GaN HEMT); a second switch coupled in series with the first switch and a second switch terminal, the second switching comprising a GaN HEMT; and at least one power source configured to provide power to the first switch and the second switch; wherein the second switch is configured to drive the first switch ON and OFF.

Switching circuit for RF currents

In one embodiment, a switching circuit includes a first switch comprising one or more transistors operably coupled in series with a first terminal, wherein each of the one or more transistors has a corresponding diode, a drain of each of the one or more transistors being operably coupled to a cathode of the corresponding diode; and a second switch comprising one or more transistors operably coupled in series with a second terminal, wherein each of the one or more transistors has a corresponding diode, a drain of each of the one or more transistors being operably coupled to a cathode of the corresponding diode; wherein a source of the one or more transistors of the first switch is operably coupled to a source of the one or more transistors of the second switch.

An RF impedance matching network includes a transformation circuit coupled to an RF input and configured to provide a transformed impedance that is less than a fixed source impedance; a first shunt circuit in parallel to the RF input, the first shunt circuit including a first shunt variable component providing a first variable capacitance or inductance; and a first virtual ground coupled to the first shunt variable component and a ground; and a second shunt circuit in parallel to the RF input and, the second shunt circuit including a second shunt variable component providing a second variable capacitance or inductance; and a second virtual ground coupled to the second shunt variable component and the ground.

In one embodiment, the invention can be a switching circuit, the switching circuit including a passive switch coupled to a first switch terminal; a driving switch coupled in series with the passive switch and a second switch terminal, the driving switch configured to turn the passive switch on and off; a power source configured to provide power to the passive switch and the driving switch; and a monitoring circuit configured to receive an indication that a switching circuit voltage exceeds a predetermined amount and, in response, reduce the power provided to the driving switch; or receive an indication that a switching circuit current exceeds a predetermined amount and, in response, reduce the power provided to the driving switch.

An RF impedance matching network includes a transformation circuit configured to provide a transformed impedance; a first shunt circuit in parallel to the RF input, the first shunt circuit including a first shunt variable capacitance component comprising (a) a plurality of first shunt capacitors coupled in parallel, and (b) a plurality of first shunt switches coupled to the plurality of first shunt capacitors and configured to connect and disconnect each of the plurality of first shunt capacitors to a first virtual ground; and a second shunt variable capacitance component including (a) a plurality of second shunt capacitors coupled in parallel, and (b) a plurality of second shunt switches coupled to the plurality of second shunt capacitors and configured to connect and disconnect each of the plurality of second shunt capacitors to a second virtual ground.

There is provided by this invention an improved rf power control device for plasma applications for optimization of the feedback control voltage in the presence of harmonic and non-harmonic spurious frequencies. In this system, an oscillator and mixer, similar to those normally used in radio receiver applications are placed at the sampled output of the solid state rf signal source used for plasma ignition. The sampled output is mixed to a low frequency and filtered to remove the spurious frequencies that is created in the non-linear plasma. In this way, the feedback power control essentially ignores the spurious frequencies. In this application, the oscillator and mixer do not interfere with other desirable system characteristics and effectively isolate the feedback control voltage from changes in plasma spurious content. This allows rf power to be delivered to the plasma with greater accuracy than would otherwise be possible with conventional power control device and methods.

RF power control device for RF plasma applications

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 a 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.

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Natick, MA, United States of America

Anton Mavretic