Patent ID: 8444870
Filing Date: 2013-05-21
Classification: H01J,H05H

Abstract:
1. A method of processing a semiconductor wafer using an inductive plasma, the method comprising: placing a semiconductor wafer on a semiconductor wafer holder in the interior of a process chamber; the process chamber comprising a plurality of dielectric windows on a surface of the processing chamber, each of the dielectric windows having a thickness of less than approximately five millimeters, the width of each of the dielectric windows being substantially smaller than the span of the chamber; admitting a process gas into the interior of the process chamber; maintaining a preselected pressure below 100 Torr in the process chamber; energizing an inductive plasma applicator external to the process chamber to generate a substantially inductive plasma in the interior of the process chamber; the inductive plasma applicator comprising a plurality of inductive coupling elements, each of the plurality of inductive coupling elements being associated with one of the plurality of dielectric windows, each of the plurality of inductive elements comprising a flat coil portion and a magnetic flux concentrator of a ferromagnetic material, the magnetic flux concentrator having an inverted U-shape cross section having an open side and two legs, the open side of the U-shaped magnetic flux concentrator positioned over the entire lateral width of the flat coil portion such that the open side of the magnetic flux concentrator faces the dielectric window associated with the inductive coupling element and such that each leg of the magnetic flux concentrator is within approximately five millimeters or less of the process chamber interior, and performing at least one treatment of the semiconductor wafer using the substantially inductive plasma; wherein the magnetic flux concentrator is operable to focus magnetic flux into the process chamber interior in a localized region proximate the dielectric window associated with the inductive coupling element such that a majority of the magnetic flux within the chamber from an inductive coupling element is localized in a volume between the dielectric window and the substrate and bounded by the lateral width of the associated flux concentrator.