A plasma reactor has plural dielectric gas injection tubes extending from a gas injection source and through a microwave guide and into the top of the reactor chamber. The semiconductor wafer rests near the bottom of the chamber on a wafer pedestal connected to a bias RF power source which is controlled independently of the microwave source coupled to the microwave guide. The microwaves from the waveguide ignite and maintain a plasma in each of the tubes. Gas flow through the tubes carries the plasmas in all the tubes into the chamber and into contact with the wafer surface.