Sputtering reactor and method of using an unbalanced magnetron

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support;
• and
• a magnetron positioned on a side of said target opposite said support and including
• a first magnet band producing a first total magnetic flux of a first magnetic polarity on a first side facing said target, and
• a second magnet band enclosing said first magnet band and producing a second total magnetic flux of a second magnetic polarity opposite said first magnetic polarity on a second side facing said target,
• wherein said second total magnetic flux is at least 1.5 times said first total magnetic flux.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support;
• and
• a magnetron positioned on a side of said target opposite said support and including
• a first magnet band producing a first total magnetic flux of a first magnetic polarity on a first side facing said target, and
• a second magnet band enclosing said first magnet band and producing a second total magnetic flux of a second magnetic polarity opposite said first magnetic polarity on a second side facing said target, wherein said second magnet band is principally disposed in a first half area of said target separated from a second half area of said target by a line passing through a center of said target
• wherein said second total magnetic flux is greater than said first total magnetic flux;
• and
• wherein said first magnet band does not extend into said second half area and wherein said second magnet band extends into said second half area but no further than 15% of a radius of said target from said center of said target.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support;
• and
• a magnetron positioned on a side of said target opposite said support and including
• a first magnet band producing a first total magnetic flux of a first magnetic polarity on a first side facing said target, wherein said first magnet band encloses an aperture formed of a non-magnetic material, and
• a second magnet band enclosing said first magnet band and producing a second total magnetic flux of a second magnetic polarity opposite said first magnetic polarity on a second side facing said target.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support;
• and
• a magnetron positioned on a side of said target opposite said support and including
• a first magnet band producing a first total magnetic flux of a first magnetic polarity on a first side facing said target, wherein said first magnet band encloses an aperture formed of a non-magnetic material, and
• a second magnet band enclosing said first magnet band and producing a second total magnetic flux of a second magnetic polarity opposite said first magnetic polarity on a second side facing said target;
• wherein said second total magnetic flux is greater than said first total magnetic flux.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support and having a center axis;
• and
• a magnetron positioned on a side of said target opposite said support, rotatable about said center axis of said target and including
• a first magnet band producing a first total magnetic flux of a first magnetic polarity on a first side facing said target, wherein said first magnet band encloses an aperture substantially free of permanently magnetized material, and
• a second magnet band enclosing said first magnet band and producing a second total magnetic flux of a second magnetic polarity opposite said first magnetic polarity on a second side facing said target, wherein said second magnet band passes through said center axis or passes within a distance of said center axis of no more than 10% of a radius of said target.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support and having a target radius extending from a target center to a target periphery;
• and
• a magnetron positioned on a side of said target opposite said support, rotatable about said target center, and including
• a plurality of first cylindrical magnets of a first magnetic polarity and having a first diameter arranged along a first portion of an oval band extending from a point within 15% of said target radius from said target center toward said target periphery;
• a plurality of second cylindrical magnets of said first magnetic polarity and having a second diameter less than said first diameter arranged along a second portion of said oval band closer to said target center than said first portion;
• and
• a plurality of third cylindrical magnets of a second magnetic polarity opposite said first magnetic polarity disposed inside said first portion of said oval band.

A magnetron sputter reactor, comprising:

• a vacuum chamber;
• a substrate support positioned in said chamber;
• a sputtering target facing said support and having a target radius extending from a target center to a target periphery;
• and
• a magnetron positioned on a side of said target opposite said support, rotatable about said target center, and including
• a plurality of first magnets of a first magnetic polarity arranged in a closed band extending from a point within 15% of said target radius from said target center toward said target periphery and having a first total magnetic flux;
• and
• at least one second magnet of a second magnetic polarity opposite said first magnetic polarity disposed inside said first band and having a second total magnetic flux;
• wherein said first total magnetic flux is at least 150% of said second total magnetic flux.

A magnetron usable with a sputtering target, comprising:

• a magnetic baseplate rotatable by a shaft aligned along a central axis positionable perpendicular to a principal face of said target;
• a plurality of first magnets of a first magnetic polarity fixed to said baseplate and arranged in a first closed band pattern;
• a first ring-shaped magnetic pole piece fixed to ends of said first magnets opposite said baseplate;
• a plurality of second magnets of a second magnetic polarity opposite said first magnetic polarity fixed to said baseplate and arranged in a second closed band pattern surrounding said first magnets;
• and
• a second ring-shaped magnetic pole piece fixed to ends of said second magnets opposite said baseplate and surrounding said first magnetic pole piece.