US Patent 7976673 RF pulsing of a narrow gap capacitively coupled reactor

An apparatus for providing a plasma etch of a layer over a wafer is provided. A capacitively coupled process chamber is provided. A gas source is provided. A first and a second electrode are provided within the process chamber. A first radio frequency power source is electrically connected to at least one of the first and second electrodes, where the first radio frequency power source provides radio frequency power. A second radio frequency power source is electrically connected to at least one of the first and second electrodes. A first modulation control is connected to the first radio frequency power source, to provide a controlled modulation of the first radio frequency power source.