Planar magnetron sputtering source producing improved coating thickness uniformity, step coverage and step coverage uniformity

Claim 1

A sputtering system for sputtering particles from a magnetron type target onto a substrate, said sputtering system comprising: a vacuum chamber for enclosing said target and substrate; a voltage source means for producing an electric field incident the magnetron target to accelerate ions into the target to sputter particles from a sputtering surface of the target; and a magnet structure positioned adjacent to another surface of the target, and including a ferromagnetic inner pole piece; a ferromagnetic outer pole piece that encircles the inner pole piece to form a gap between these two pole pieces; magnet means for producing a magnetic field across the gap between these two pole pieces; and motor means for rotating these pole pieces at a common rotation rate about an axis A that is substantially perpendicular to said pole pieces and on which said wafer is to be centered perpendicular to this axis; said gap having the shape of a closed loop for which the fraction of gap at each radial distance ρ t from axis A is substantially equal to a distribution S i (ρ t ) that produces a uniform thickness of sputtered particles on said substrate.

Claim 15

A method of sputtering particles from a magnetron-type target onto a surface area of a substrate, comprising the steps of: producing an electric field to accelerate ions into the target to sputter particles from a sputtering surface of the target; positioning an inner ferromagnetic pole piece and an outer ferromagnetic pole piece adjacent to another surface of the target, so that the outer pole piece encircles the inner pole piece with a gap between the two pole pieces; producing a magnetic field across the gap between the pole pieces; rotating said pole pieces at a common rotation rate about an axis which is substantially perpendicular to, and substantially centered in, said substrate surface area; and establishing the respective shapes of said two pole pieces so that said gap between them has the shape of a closed loop having a radial distance ρ t from the axis which varies with angular position about the axis is such a way that the distribution S i (ρ t ) of such distances ρ t produces a substantially uniform spatial distribution of sputtered particles over said substrate surface area.

Claim 16

A method of sputtering particles from a magnetron-type target onto a surface area of a substrate, comprising the steps of: producing an electric field to accelerate ions into the target to sputter particles from a sputtering surface of the target; positioning an inner ferromagnetic pole piece and an outer ferromagnetic pole piece adjacent to another surface of the target, so that the outer pole piece encircles the inner pole piece with a gap between the two pole pieces; producing a magnetic field across the gap between the pole pieces; rotating said pole pieces at a common rotation rate about an axis which is substantially perpendicular to, and substantially centered in, said substrate surface area; and establishing the respective shapes of said two pole pieces so that said gap between them has the shape of a closed loop having a radial distance ρ t from the axis which varies with angular position about the axis is such a way that the distribution S i (ρ t ) of such distances ρ t produces a substantially uniform spatial distribution of sputtered particles over said substrate surface area.