Abstract:
Methods and apparatus for generating a variable clock used to control a component of a substrate processing system are provided herein. In some embodiments, an apparatus for controlling a substrate processing system includes: a phase locked loop circuit for generating a relative clock that is phase locked to a variable frequency signal being used by a substrate processing chamber; and a controller, coupled to the phase locked loop circuit, for producing a control signal for a component of the substrate processing system, wherein the control signal is based upon the relative clock and an operating indicia of the substrate processing system.
Abstract:
An RF current probe is encapsulated in a conductive housing to permit its placement inside a plasma reactor chamber. An RF voltage probe is adapted to have a long coaxial cable to permit a measuring device to be connected remotely from the probe without distorting the voltage measurement.
Abstract:
Plasma is generated in a semiconductor process chamber by a plurality of microwave inputs with slow or fast rotation. Radial uniformity of the plasma is controlled by regulating the power ratio of a center-high mode and an edge-high mode of the plurality of microwave inputs into a microwave cavity. The radial uniformity of the generated plasma in a plasma chamber is attained by adjusting the power ratio for the two modes without inputting time-splitting parameters for each mode.