Patent ID: 8547020

Claim:
A radio frequency plasma generating device, comprising: a power supply circuit having a switch configured to be controlled by a control signal to apply an amplified voltage to an output of the power supply circuit selectively at each of a plurality of frequencies responsive to the control signal; at least two plasma generation circuits connected in parallel to the output of the power supply circuit, each said plasma generation circuit including a resonator having a first resonance frequency and a bandwidth and being configured to generate plasma responsive to application of the amplified voltage to the output of the power supply circuit at a corresponding one of the plurality of frequencies; a frequency-shifter, different from the plasma generation circuits, including at least one inductor connected between the power supply circuit and at least a first one of the plasma generation circuits; and a device configured to control the power supply circuit and to control the frequency of the control signal to output each one of the plurality of frequencies to the plasma generation circuits to selectively control each plasma generation circuit according to the control frequency used, wherein the plasma generation circuits are identical in configuration, the first resonance frequencies of the resonators being the same, and the bandwidth of the resonators being the same, wherein the frequency shifter is connected to said first plasma generation circuit such that a second resonance frequency, less than the first resonance frequency, is the corresponding one of the plurality of frequencies of the amplified voltage applied to the output of the power supply circuit to cause plasma generation by said first plasma generation circuit, and wherein each said frequency of the amplified voltage applied to the output of the power supply circuit is separated from all other of said output frequencies by an amount at least equal to a non-zero integer multiple of the bandwidth of the resonators.