Recent developments in inverted cylindrical magnetron sputtering

Inverted cylindrical magnetron cathodes sputter from the interior surfaces of cylindrical targets and simultaneously deposit material on all sides of three-dimensional substrates. Since their invention in the 1970s, they have been widely used to coat wires, fibers and ribbons. As the use of coatings on complex shapes has increased, cylindrical magnetrons have been adopted for a variety of applications, ranging from X-ray telescope mirrors to biomedical implants. This paper describes the features of these devices and compares their operation and coating characteristics to those of planar magnetrons. Recent developments in sputtering dielectric materials are described and new methods that take advantage of cylindrical magnetron designs to produce high ionization densities at the substrates are discussed.