Ring cathode for use in a magnetron sputtering device

A magnetron sputtering device including:

• a planetary drive system having a central rotation axis C for primary rotation, and supporting a plurality of planets, each planet having a secondary axis of rotation at a planet center point Cs, and each planet representing a coating area described by rw the planet radius, the planetary drive system having a carrier radius rC from the central rotation axis C to a planet center point Cs;
• a ring shaped cathode including a ring shaped target comprising material for forming a coating, the cathode having a center point Cc, an outer radius r2 greater than the planet radius (r2>rW), an inner radius r1 greater than one quarter of the outer radius (r2>r1>¼*r2);
• wherein the cathode center point Cc is disposed an offset distance rT between ⅔ and 4/3 of the carrier radius rC from the central rotation axis C (⅔*rC<rT< 4/3*rC), and the offset distance rT is greater than one half the outer radius of the cathode (rT>½*r2);
• and wherein a throw distance h vertically from a target surface to a planet surface is between one third of the outer radius r2 of the cathode and one times the outer radius of the cathode (⅓*r2<h<r2);
• a chamber for housing the cathode and the planetary drive system adapted to be evacuated in operation;
• and
• a gas delivery system for providing a flow of sputter gas into the chamber.