Abstract: An electro-magnet array for use in a sputtering apparatus. The array has a magnetisable core member extending substantially horizontally and having magnetisable outward projections arranged as at least two pairs of symmetrically opposed projections projecting outwardly from the core member. A pole member is associated with each projection and vertically displaced with respect thereto. A magnetisable coupler is arranged to couple each pole piece magnetically to its respective projection. A magnetising coil around each projection is arranged for producing a magnetic field aligned substantially with a horizontal axis of symmetry of its respective projection in dependence upon the direction of flow of electric current through the magnetising coil.

Abstract: A sputtering apparatus includes a rotatable array plate and a magnetic array including a group of permanent magnets arranged around the plate periphery in one or more quadrants. Each magnet is perpendicular to the plate, having a pole of a first polarity facing toward the target. A bar permanent magnet is affixed to the plate within the same quadrant of a group of magnets and is located between a center axis of rotation and the magnet group. The bar permanent magnet is perpendicular to the plate, having a pole of a second polarity facing toward the target. The magnets create a closed-loop static magnetic field that is substantially triangular in shape, concentrated in the quadrant, and offset from the center axis of rotation. The magnets in one quadrant may be replicated to fill up to four quadrants, and additional bar magnets are arranged to create a rotating magnetic field at the target that patterns the plasma to a maximum plasma density in the shape of a kidney.