Patent ID: 11942307
Assignee: TOKYO ELECTRON LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A system for plasma processing comprising:
a plasma processing chamber comprising:
a first radio frequency (RF) electrode;
a second RF electrode; and
a substrate holder configured to hold a semiconductor substrate in the plasma processing chamber;

a processor;
a non-transitory memory storing a program to be executed in the processor, the program comprising:
instructions to couple an RF signal source to the first RF electrode; and
instructions to apply a bias signal between the first RF electrode and the second RF electrode, the bias signal having a bipolar DC (B-DC) waveform comprising a plurality of B-DC pulses, each of the B-DC pulses comprising:
a negative bias duration during which the pulse has negative polarity relative to a reference potential,
a positive bias duration during which the pulse has positive polarity relative to the reference potential, and
a neutral bias duration during which the pulse has neutral polarity relative to the reference potential;

a continuous wave (CW) RF source signal source;
a programmable continuous B-DC bias signal source;
a programmable first chopper coupled to the CW-RF source signal source;
a programmable second chopper coupled to the continuous B-DC bias signal source; and
a timing controller coupled to the continuous B-DC bias signal source, the first chopper, and the second chopper, wherein the timing controller is configured to receive commands from the processor which, when executed, synchronously controls an output signal of the first chopper, an output signal of the second chopper and, and an output signal of the continuous B-DC bias signal source.