Patent ID: RE45280

Claim:
An apparatus for generating plasma, the apparatus comprising: a plasma reaction chamber having a window forming a magnetic/electrical held path into the chamber and a process gas supply for introducing process gas into the chamber; a coil comprising at least a first coil segment and a second coil segment, the first and second coil segments being connected in series and disposed proximate an exterior surface of the window of the chamber so electromagnetic fields from said first and second coil segments are coupled through the window into the chamber; a radio frequency source for coupling r.f. energy to the coil arrangement , the radio frequency source being effective to resonate a radio frequency current in the first and second coils coil segments ; and a power distributing component connected to one of the coil segments fee controlling the flow of radio frequency current from the source through the first and second coil segments so different maximum radio frequency current amplitudes selectively flow from the source through the first and second coil segments at the same time to cause the process gas introduced into the chamber to be excited into a plasma having a relatively uniform plasma density in an area spanned by the first and second coil segments.