Christoph Adelhelm¹, *Christian Linke¹, Harald Köstenbauer¹, Enrico Franzke¹, Jörg Winkler¹, Sebastian Seibold², Wilfried Walgram², Marcus Wolff², Peter Polcik^2
1Plansee SE, Reutte, Austria; ²Plansee Composite Materials, Lechbruck am See, Germany
Plansee continuously develops new thin film coating materials for applications in the display, solar, microelectronics and hardcoating industry. Molybdenum is used in thin-film transistors (TFT) for displays due to its superior adhesion on glass and good conductivity. For future high-end applications, lower resistance metal lines are required in the TFT. By adding W-based seed-layers, the conductivity of Mo can be improved by up to 30%. MoO_x ceramic targets have been introduced into the manufacturing process of high-end flat panel displays. Dark MoO_x films are deposited to cover reflecting areas and provide superior contrast. By varying the oxygen content and metal-doping in the target, the optical properties can be tuned. Other applications can be addressed by adding O₂ during film deposition: wide bandgap, transparent MoO_x films show interesting electronic properties. MoO_x films are introduced together with TiO_x as ITO replacement for perovskite solar cells. For TiC films it is beneficial to deposit from a TiC ceramic target in an argon atmosphere instead of creating the coating with a Ti target in hydrocarbon atmosphere. The gaseous carbon contaminates the coating chamber and time-consuming cleaning is necessary. Secondly, sputtering from ceramic targets leads to a better process stability, as the coating composition is pre-defined by the target composition.