Fitting wood and wood-based substrates with smart or intelligent surfaces is a prerequisite for using wood materials in smart homes in future. This requires the integration of electrically conductive layers, structures and sensors in the surface. To this end, the ConWood project has the aim of using magnetron sputtering to deposit a wide variety of metals, metal alloys and metal oxides on wood and wood-based materials to give the substrates the long-lasting electrical conductivity needed for each particular application.

The ConWood project is examining magnetron sputtering for depositing thin metallic layers by means of physical vapour deposition (PVD). With this technique, a wide variety of metals, metal alloys and transparent, conductive oxides can be deposited directly on wood and wood-based substrates irrespective of the substrate’s thickness, size, geometry and surface properties. The chief advantages of magnetron sputtering are the creation of outstandingly homogeneous films (with respect to thickness, distribution), the low thermal impact under 50 °C when a suitable ion and plasma-enhanced process is used, and avoidance of swelling effects in wood, wood material and paper substrates.

The ConWood project focuses primarily on developing and optimizing the PVD process for depositing electrically conductive films on wood, wood materials and paper surfaces in particular. In the first project phase, various wood and wood-based substrates with a metallic coating were successfully produced which possess the long-lasting electrical conductivity required by the application in question.

Outlook: The wide range of coating materials (metals, alloys and metal oxides) and the production of multifunctional layers also create the potential for new, innovative applications for wood and wood-based materials, for example thermoelectric functionalization of wood surfaces. This will be the object of research in the next project phase. Potential uses are expected in electronic components and sensors that can be integrated in furniture or facade elements and have electrically conductive, thermoelectric or capacitor properties depending on the final application.

(c)Wood K Plus