Patent ID: 8277906

Claim:
A method of processing a substrate, the method comprising: loading a substrate in a chamber; processing the substrate with a first plasma mode; and then processing the substrate with a second plasma mode, wherein at least one of the first plasma mode and the second plasma mode is a time-modulation mode in which a plasma induced in the chamber is periodically turned on and off to reduce plasma-induced damage in the substrate, wherein the time-modulation mode is controlled by periodically turning on and off a power supply for inducing the plasma, and wherein the power supply for inducing the plasma includes a first-radio-frequency power supplied to upper electrodes disposed on the substrate and a second-radio-frequency power supplied to lower electrodes disposed under the substrate, and wherein, in the time-modulation mode, both the first-radio-frequency power and the second-radio-frequency power are periodically turned on and off.