Adjustable non-dissipative voltage boosting snubber network for achieving large boost voltages
AssigneeAdvanced Energy Industries, Inc.
InventorsKenneth W. Finley, Hendrik Walde
Life of this patent
Estimating the term…
Abstract
This disclosure describes a non-dissipative snubber circuit configured to boost a voltage applied to a load after the load's impedance rises rapidly. The voltage boost can thereby cause more rapid current ramping after a decrease in power delivery to the load which results from the load impedance rise. In particular, the snubber can comprise a combination of a unidirectional switch, a voltage multiplier, and a current limiter. In some cases, these components can be a diode, voltage doubler, and an inductor, respectively.
Claims11
A pulsed DC power supply system that provides pulsed DC power to a plurality of anodeless electrodes sustaining a plasma in a plasma processing chamber, the pulsed DC power supply system comprising:
- a DC power supply coupled to and providing a first DC power to a first and second rail, such that a rail voltage exists across the first and second rails;
- a switching circuit coupled to the first and second rails and receiving the first DC power via the first and second rails and converting the first DC power to a first pulsed DC voltage configured for delivery to at least a first anodeless electrode of the plasma processing chamber;
- and
- a voltage-boosting circuit coupled between the first and second rails, the voltage-boosting circuit comprising:
- a first diode coupled between the first rail and a first electrical node and forward biased when a voltage measured from the first rail to the first electrical node is sufficiently positive to forward bias the first diode;
- a capacitive element coupled between the first electrical node and the second rail;
- a switch selectively coupling the first electrical node and a second electrical node;
- a second diode coupled between the second rail and the second electrical node and forward biased when a voltage measured from the second rail to the second electrical node is sufficiently positive to forward bias the second electrical node;
- and
- an inductive element coupled between the second electrical node and the first rail.
A pulsed DC power supply system that provides pulsed DC power to a plurality of anodeless electrodes sustaining a plasma in a plasma processing chamber, the pulsed DC power supply system comprising:
- a DC power supply coupled to and providing a first DC power to a first and second rail, such that a rail voltage exists across the first and second rails;
- and
- a switching circuit coupled to the first and second rails and receiving the first DC power via the first and second rails and converting the first DC power to a first pulsed DC voltage configured for delivery to at least a first anodeless electrode of the plasma processing chamber;
- and
- a voltage-boosting circuit coupled between the first and second rails, the voltage-boosting circuit comprising:
- a first diode coupled between the first rail and a first electrical node, an anode of the first diode being at a voltage of the first rail;
- a capacitive element coupled between the first electrical node and the second rail;
- a switch selectively coupling the first electrical node and a second electrical node;
- a second diode coupled between the second rail and the second electrical node, an anode of the second diode being at a voltage of the second rail;
- and
- an inductive element coupled between the second electrical node and the first rail.
Dependencies are inferred from the claim text.