Methods and apparatus for synchronizing RF pulses in a plasma processing system

摘要

A synchronized pulsing arrangement for providing at least two synchronized pulsing RF signals to a plasma processing chamber of a plasma processing system is provided. The arrangement includes a first RF generator for providing a first RF signal. The first RF signal is provided to the plasma processing chamber to energize a plasma therein, the first RF signal representing a pulsing RF signal. The arrangement also includes a second RF generator for providing a second RF signal to the plasma processing chamber. The second RF generator has a sensor subsystem for detecting values of at least one parameter associated with the plasma processing chamber that reflects whether the first RF signal is pulsed high or pulsed low and a pulse controlling subsystem for pulsing the second RF signal responsive to the detecting the values of at least one parameter.

主权项

1. A synchronized pulsing arrangement comprising:
a first RF generator for providing a first RF signal, said first RF signal provided to a plasma processing chamber to energize plasma therein, said first RF signal representing a pulsing RF signal; and a second RF generator for providing a second RF signal to said plasma processing chamber, said second RF generator having a sensor subsystem for detecting at an output of the second RF generator values of at least one parameter associated with said plasma processing chamber indicating a change in pulsing of said first RF signal from a first state to a second state, said second RF generator having a pulse controlling subsystem for pulsing said second RF signal provided by the second RF generator in response to detecting that the values of said at least one parameter at the output of the second RF generator indicate a change in pulsing of said first RF signal from the first state to the second state, wherein the first RF signal in the first state has a different forward power level from a forward power level of the first RF signal in the second state, wherein the first RF generator and the sensor subsystem of the second RF generator are coupled to an impedance matching network.