Sputtering cathode, sputtering cathode assembly, and sputtering apparatus

A sputtering cathode assembly, comprising:

• a pair of hollow cylindrical sputtering targets arranged parallel to each other and opposing each other across an interior region of the sputtering cathode assembly, with each of the hollow cylindrical sputtering targets being supported for rotation about a longitudinal central axis thereof;
• a pair of short-side portions configured as sputtering targets, each of which extends between the pair of hollow cylindrical sputtering targets near respective ends thereof, the pair of short-side portions being arranged perpendicularly to the hollow cylindrical sputtering targets and opposing each other across the interior region of the sputtering cathode assembly, the short-side portions each having a rectangular transverse cross-section at a lengthwise central portion thereof;
• a pair of long-side permanent magnets, each of which is disposed within an associated one of the hollow cylindrical sputtering targets, with each of the long-side permanent magnets extending lengthwise within the associated hollow cylindrical sputtering target with a north pole disposed toward one side of the associated hollow cylindrical sputtering target and a south pole disposed toward an opposite side of the associated hollow cylindrical sputtering target;
• a pair of short-side permanent magnets associated with and located on an outer-facing side of each of the short-side portions, wherein, for each pair of the short-side permanent magnets, 1) one of the short-side permanent magnets of the pair has a short-side-facing north pole that faces the associated short-side portion and an away-facing south pole that faces away from the associated short-side portion, and 2) the other short-side permanent magnet of the pair has a short-side-facing south pole that faces the associated short-side portion and an away-facing north pole that faces away from the associated short-side portion;
• and
• a magnetically conductive yoke associated with each of the short-side portions, wherein for each of the short-side portions, the associated magnetically conductive yoke extends between the away-facing south pole of said one of the associated short-side permanent magnets and the away-facing north pole of said another of the associated short-side permanent magnets;
• wherein
• A) 1) the north poles of the long-side permanent magnets and the short-side-facing north poles of the short-side permanent magnets are all disposed toward a first, upper side of the sputtering cathode assembly;
• and 2) the south poles of the long-side permanent magnets and the short-side-facing south poles of the short-side permanent magnets are all disposed toward a second, lower side of the sputtering cathode assembly;
• or
• B) 1) the south poles of the long-side permanent magnets and the short-side-facing south poles of the short-side permanent magnets are all disposed toward a first, upper side of the sputtering cathode assembly;
• and 2) the north poles of the long-side permanent magnets and the short-side-facing north poles of the short-side permanent magnets are all disposed toward a second, lower side of the sputtering cathode assembly;
• and
• wherein ends of the short-side portions are concavely rounded in a manner that corresponds to the cylindrical shape of the hollow cylindrical sputtering targets to conform to the respective ends of the hollow cylindrical sputtering targets.