Patent attributes
An arc suppression device includes an AC to DC converter, a switch, a resistor and a controller. The switch is coupled between the AC to DC converter and a plasma chamber. The resistor is coupled in parallel with the switch. The AC to DC converter is configured to convert an AC voltage into a DC voltage for providing to the plasma chamber. The controller is configured to detect a unit-time rate of change (ROC) of a plasma current received by the plasma chamber. When the controller determines that the unit-time ROC of the plasma current is larger than a first unit-time ROC threshold, the controller controls the switch to electrically isolate the AC to DC converter and the plasma chamber to reduce the plasma current to a first current value through the resistor.