Introduction to magnetron sputtering

Plasma-based physical vapor deposition (PVD) methods have found widespread use in various industrial applications. In plasma-based PVD processes, the deposition species are either vaporized by thermal evaporation or by sputtering from a source (the cathode target) by ion bombardment. Initially, the dc glow discharge or the dc diode sputtering discharge was used as a sputter source followed by the magnetron sputtering technique, which was developed during the 1960s and 1970s. With the introduction of magnetron sputtering, the disadvantages of diode sputtering, such as poor deposition rate, were overcome as the operating pressure could be reduced while maintaining the energy of the sputtered species, often resulting in improved film properties. In this chapter we discuss the basics of the sputtering process, give an overview of the dc glow discharge, and review the basic physics relevant to the maintenance of the discharge and the sputter processes. Then we discuss the dc glow discharge and its role as a sputter source and how it evolves into the magnetron sputtering discharge. We also discuss various magnetron sputtering configurations in use for a wide range of applications both under laboratory and industrial arrangements. Finally, we introduce pulsed magnetron discharges including high power impulse magnetron sputtering (HiPIMS) discharges.