Split magnet ring on a magnetron sputter chamber
AssigneeApplied Materials, Inc.
InventorXinyu Fu
Life of this patent
Estimating the term…
Abstract
A split magnet ring, particularly useful in a magnetron plasma reactor sputter depositing tantalum or tungsten or other barrier metal into a via and also resputter etching the deposited material from the bottom of the via onto the via sidewalls. The magnet ring includes two annular magnet rings composed of the same axial polarity separated by a non-magnetic spacing of at least the axial length of one magnet and associated poles. A small unbalanced magnetrons rotates about the back of the target having an outer pole of the same polarity as the ring magnets surrounding a weaker inner pole of the opposite pole.
Claims21
A sputter reactor, comprising:
- a vacuum chamber having sidewalls arranged about a central axis;
- a sputter target sealed to one end of the vacuum chamber;
- a pedestal arranged along the central axis in opposition to the sputter target for supporting a substrate to be processed;
- and
- a split magnet ring comprising permanent magnets arranged about the central axis, disposed at least partially along the central axis between the sputter target and the pedestal, and including at least two sub-rings of a first magnetic polarity along the central axis, an axial spacing along the central axis of substantially reduced magnetization being maintained between the sub-rings.
A split magnet ring configured to be arranged about a sidewall of a sputter reactor and comprising at least two sub-rings fixable together to form a ring and each sub-ring comprising:
- a partial collar fixable to at least one other partial collar;
- and
- permanent rod magnets axially extending parallel to a central axis of the two fixed partial collars and held in the partial collar in at least two partially annular arrangements with axial spaces therebetween, a spacing between the two partially annular arrangements of magnets being at least as great as an individual length of the magnets.
A method of sputtering a metal onto a substrate, comprising:
- providing a vacuum chamber arranged about a central axis;
- affixing a target to the vacuum chamber comprising a surface comprising a metal;
- supporting a substrate to be processed on a pedestal electrode in opposition to the target;
- applying DC power to the target to excite a plasma within the chamber to sputter the metal from the target;
- rotating an unbalanced magnetron about the central axis at the back of the target;
- RF biasing the pedestal electrode;
- and
- providing a split magnet ring comprising permanent magnets surrounding the central axis in a region between the target and the pedestal electrode, wherein the split magnet ring includes two magnet rings of a first magnetic polarity along the central axis and separated by a substantially non-magnetic spacing having an axial length at least as great as axial lengths of either of the magnet rings.
Dependencies are inferred from the claim text.