Patent ID: 7780864

Claim:
A method of processing a workpiece in the chamber of a plasma reactor, comprising: introducing a process gas into the chamber; simultaneously (a) capacitively coupling VHF plasma source power from a VHF power generator into a process region of the chamber that overlies the wafer, and (b) inductively coupling HF plasma source power from an HF generator into said process region; applying LF bias power and HF bias power to said workpiece; adjusting a plasma ion density radial distribution in said process region by adjusting the ratio between the amounts of said capacitively coupled VHF power and said inductively coupled power, wherein said adjusting comprises one of: (a) changing said radial distribution to a more center high distribution by increasing the output power said VHF power generator relative to the output power of said HF generator, (b) changing said radial distribution to a more edge high distribution by increasing the output power of said HF generator relative to the output power of said VHF generator; and controlling a sum of said VHF plasma source power and said HF plasma source power in accordance with a desired plasma ion density.