Abstract: The invention is an expandable magnetron sputtering system that does not require an external vacuum chamber and has a valveless, continuously-open, straight through, air-to-air sputtering path. The system is based on connectable cathode modules and anode modules that each have an opposed pair of apertures. The modules themselves may beneficially serve as part of an integral vacuum chamber. Using vacuum-tight connectors, the modules are connected end-to-end with their apertures aligned to form the vacuum-tight sputtering path. Differential vacuum entries are provided on opposite sides of the sputtering path.

Abstract: The invention is an expandable magnetron sputtering system based on an elongated hollow cylindrical cathode member. A magnetic field is provided parallel to an axial wall of the hollow cathode member to create a physical trap for containing a glow discharge therein. Removable end plugs are provided, if necessary, to help create the physical trap. The hollow cathode member may be solid or any contain one or more slots, as appropriate, for the substrate to be coated (filament-like versus planar) and the mode of operation selected (pass-by versus pass-through). The cathode members may be connected together (with anodes as needed) to extend the length of a sputtering path. A plurality of single-slot cathodes may be cost effectively formed and operated in a single monolithic slab of material.