Apparatus and method for improving plasma distribution and performance in an inductively coupled plasma

A processing system for processing a substrate with a plasma, the system comprising:

• a processing chamber defining a processing space and including a substrate support therein for supporting a substrate in the processing space;
• a gas inlet for introducing a process gas into said processing space;
• a plasma source operable for creating a plasma in the processing space from process gas introduced therein, the plasma source comprising:
• a dielectric window having a generally planar surface, the dielectric window interfacing with the processing chamber proximate the processing space,
• an antenna element positioned outside of the chamber and proximate the dielectric window, the antenna element having opposing ends and operable for inductively coupling electrical energy through the dielectric window and into the processing space to create a plasma therein;
• the antenna element comprising an electrical conductor configured to have multiple turns which are wound successively along the length of the antenna element between the opposing ends;
• segments of the conductor turns being oriented in a first plane generally parallel to said window planar surface and the turn segments curving one of concavely and convexly with respect to a respective end of the antenna element, and at least one segment of a conductor turn being oriented in a second plane which is angled from the first plane.