Arc management with voltage reversal and improved recovery
View Patent ↗Systems and methods for arc handling in plasma processing operations are disclosed. The method includes providing current with a power supply to a plasma load at a first voltage polarity and energizing an energy storage device so when it is energized, the energy storage device applies a reverse polarity voltage that has a magnitude that is as least as great as the first voltage polarity. When an arc is detected, power is applied from the energy storage device to the plasma load with a reverse polarity voltage that has a polarity that is opposite of the first voltage polarity, the application of the reverse polarity voltage to the plasma load decreases a level of the current that is provided to the plasma load.
1. An apparatus for arc handling, comprising:
a positive rail and a negative rail that are disposed to form an electrical link between a plasma chamber and a positive output and a negative output, respectively, of a power supply;
an arc detection component to detect an occurrence of an arc in the power supply;
a voltage reversal component coupled across the positive rail and the negative rail, the voltage reversal component including:
an energy storage component disposed between a first and second switches, the first switch is coupled to the positive rail and a first terminal of the energy storage component and the second switch is coupled between the negative rail and a second terminal of the energy storage component,
a control component that is coupled to the arc detection component and the first and second switches of the voltage reversal component, the control component closes the first and second switches when an arc is detected to apply a negative potential of the energy storage component to the positive rail and a positive potential of the energy storage component to the negative rail, the control component then opens one of the first and second switches when the arc is extinguished before opening both the first and second switches.
2. The apparatus of claim 1 , including:
a charging-power supply to charge the energy storage device to a charging voltage that exceeds a voltage of the power supply.
3. The apparatus of claim 1 including a voltage booster to charge the energy storage device with a boosted voltage that exceeds a voltage of the power supply.
4. The apparatus of claim 1 including a recovery filter that is switchably coupled between the positive and negative rails, the control component reengages the recovery filter when power at the first voltage polarity is applied again to stabilize the voltage at the first polarity and prevent the arc detection component from falsely detecting arcs.
5. The apparatus of claim 1 , wherein the voltage reversal component includes:
a first diode coupled between the positive rail and the second terminal; and
a second diode coupled between the first terminal and the negative rail, wherein the energy storage component is charged through the first and second diodes when power is applied to the positive and negative rails.
6. The apparatus of claim 5 , wherein the energy storage component includes a capacitor.
7. The apparatus of claim 1 , including a transformer coupled to the positive and negative rails to provide a charging voltage to the energy storage component.
8. The apparatus of claim 1 including the power supply coupled to the positive and negative rails.