Thin functional coatings are the key to new and superior products in nearly all industrial branches. The most flexible and widely used technology for the deposition of thin films are plasma processes. These technologies are the first choice for an enormous bandwidth of materials and functions to be realized. The talk will give an overview of functional coatings with recent applications and will focus on the available process technologies for thin film deposition ranging from well established PVD processes like DC magnetron sputtering and PACVD to new and specialized technologies like atmospheric pressure plasma processes or gas flow sputtering and hot topic technologies of highly ionised pulse plasma processes (HIPP).

Hard and Superhard Coatings. A well established class of hard coatings, e.g. for automotive applications, mechanical engineering, or tools are diamond like carbon coatings (DLC) and their metal containing derivatives. They are prepared by plasma processes such as PACVD, DC magnetron sputtering, and plasma activated evaporation. A new approach for the production of multilayer hard coatings for the protection against erosion under severe conditions, e.g. in aircraft engines, is the hollow cathode gas flow sputtering technique (GFS). A very promising new superhard material for tools is cubic boron nitride (cBN) deposited by RF magnetron sputtering. This coating material offers several advantages like very high hardness, high oxidation resistance, low affinity to iron, and very high wear resistance.

Electrical and Optical Coatings. Transparent conductive oxides TCOs are of major importance in photovoltaics or displays and can be deposited by reactive magnetron sputtering. A new, unique patented coat and bend process for the deposition of TCOs on position 1 is the tailored high power impulse magnetron sputtering (HiPIMS) deposition for films with defined nanocrystalline structure. After annealing and bending excellent electrical properties can be realised. For insulation, e.g. in thin film sensors, alumina coatings with high deposition rate and breakdown voltage exceeding 1.5 kV/µm were realized by reactive MF sputtering and modulated pulse power plasma processes MPP. For force and load measurements, e.g. in adaptive systems or sensor modules carbon based films with high wear resistance and piezoresistive properties are deposited by PACVD. The application can be realised either as strain gauges on parts experiencing mechanical deformation or as direct contact in force closure. Therefore, force and load measurement without significantly modifying the dimensions of technical parts are accessible as additional information.

Photocatalytically Active Coatings. Photo induced hydrophilicity and photocatalytic decomposition of organic material can be achieved by coatings with crystalline TiO₂. These coatings can be deposited by plasma based processes even on temperature sensitive surfaces, for example on polycarbonate. In order to improve the activity in visible light TiO₂ can be doped by different elements.

Surface Modification. Targeted surface functionalization or coating can be achieved by means of atmospheric pressure plasma processes. Therefore, adhesion of coatings, inks, or glues is improved and adhesion of biomolecules can be targeted/controlled. Using microplasmas, a patterned surface modification can be created for subsequent processes like selective bonding or fully additive wet chemical metallization for RFID tags or flexible printed circuits.