Switching circuit
AssigneeReno Technologies, Inc.
InventorsAnton Mavretic, Ian M. Costanzo, Ronald Anthony Decker
Life of this patent
Estimating the term…
Abstract
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.
Claims20
An impedance matching circuit comprising:
- a radio frequency (RF) input configured to couple to an RF source;
- an RF output configured to couple to a plasma chamber;
- and
- a control circuit;
- and
- a variable reactance circuit operably coupled to the control circuit and configured to provide a variable reactance, the variable reactance circuit comprising fixed reactance components and corresponding switching circuits, wherein each of the switching circuits comprises:
- a diode;
- and
- a driver circuit operably coupled to the diode and configured to switch the diode, the driver circuit comprising, 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;
- wherein, for each diode of each switching circuit, the control circuit is configured to (a) receive a value related to a voltage drop on the resistor, and (b) based on the value related to the voltage drop, adjust the bias current being provided by the biasing current source.
A semiconductor processing tool comprising:
- a plasma chamber configured to deposit a material onto a substrate or etch a material from the substrate;
- and
- an impedance matching circuit operably coupled to the plasma chamber, the matching circuit comprising:
- an RF input configured to couple to an RF source;
- an RF output configured to couple to the plasma chamber;
- and
- a control circuit;
- and
- a variable reactance circuit operably coupled to the control circuit and configured to provide a variable reactance, the variable reactance circuit comprising fixed reactance components and corresponding switching circuits, wherein each of the switching circuits comprises:
- a diode;
- and
- a driver circuit operably coupled to the diode and configured to switch the diode, the driver circuit comprising, 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;
- wherein, for each diode of each switching circuit, the control circuit is configured to (a) receive a value related to a voltage drop on the resistor, and (b) based on the value related to the voltage drop, adjust the bias current being provided by the biasing current source.
A method of impedance matching comprising:
- operably coupling a matching network between an RF source and a plasma chamber, the matching network comprising:
- a control circuit;
- and
- a variable reactance circuit operably coupled to the control circuit, the variable reactance circuit comprising fixed reactance components and corresponding switching circuits, wherein each of the switching circuits comprises:
- a diode;
- and
- a driver circuit operably coupled to the diode and configured to switch the diode, the driver circuit comprising, 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;
- altering a reactance of the variable reactance circuit by altering a state of at least one of the switching circuits;
- for each diode of each switching circuit:
- receiving a value related to a voltage drop on the resistor;
- based on the value related to the voltage drop, adjusting the bias current being provided by the biasing current source.
Dependencies are inferred from the claim text.