Reactive magnetron sputtering

Hard material coatings and decorative coatings based on aluminium, titanium, zirconium, chromium and ceramics are applied (sputtered) to tools, components and other products using the reactive magnetron sputtering process.

Inside a vacuum chamber, the coating material is placed opposite the product that is to be coated. The chamber is filled with argon gas and a voltage of several hundred volts is applied. This ignites a plasma consisting of positively charged argon particles (argon ions) and free electrons. The positively charged argon ions are accelerated towards the negatively charged cathode. Here they collide with the surface of the target with a high kinetic energy of up to several hundred electron volts (eV). This causes the argon particles to dislodge atoms from the surface of the sputtering target. A potential is now applied between the vacuum chamber and the substrate. This accelerates the particles from the hard material in the direction of the workpiece that is to be coated. Here, they react with a reactive gas that is fed in externally (nitrogen, carbon or oxygen) and are deposited on the workpiece as a fine nitride, carbide or oxide hard-material layer.