Abstract: A magnetron including a target (2) for sputtering onto a substrate in described. The magnetron comprises a magnetic field generator (4) for generating a closed loop magnetic field adapted to generate a plasma race-track above the target (2) and a driving device for establishing relative substantially translational movement between the race-track and the target (2) and adapted to influence the magnetic field generated by the magnetic field generator (4) at least during part of the relative substantially translational movement, the distance between any point on the race track and the momentarily closest part of the one or more pieces (50) of ferromagnetic material varying in accordance with the relative substantially translational movement of the race-track and the target (2).

Abstract: A sputtering magnetron with a rotating cylindrical target and a stationary magnet assembly (22, 24*) is described, the magnet assembly (22, 24*) being adapted to produce an elongate plasma race-track on the surface of the target, the elongate race-track having substantially parallel tracks over a substantial portion of its length and being closed at each end by end portions (22′), wherein the spacing between the tracks of the race-track is increased locally to materially effect sputtering onto a substrate. The increase in spacing may be at the end portions or along the parallel track portion. The increase in spacing may provide more even erosion of the target beneath the end portions of the race-track, and provide more even coatings on the substrate.

Abstract: The present invention provides a planar magnetron including a surface for mounting a planar substantially polygonal target (2) having a substantially central target area for sputtering onto a substrate. The magnetron comprises an array of magnets (4) defining a closed loop magnetic field for generating an elongated plasma race-track above the target (2). Means for establishing cyclical, relative, substantially translational movement between the race-track and the target support surface are provided, the substantially translational movement being substantially parallel to this surface and the trace of the substantially translational movement being a two-dimensional figure. The periphery of the race-track lies substantially within said substantially central target area throughout each cycle, the establishing means being adapted to provide a substantially uniform erosion of the target (2) at least within said substantially central target area.