Fabrication of Defined Micron-Scale Ceramic Surface Features

Urs P. Schönholzer, René Hummel, Ludwig J. Gauckler

ETH Zurich, Department of Materials, CH-8092 Zurich, Switzerland

Processing routes for both, patterned ceramic surfaces and patterned ceramic coatings are reported. The methods are based on slip casting of suspensions with high solids loadings. Micron-scale surface structures are generated by slip casting into nonporous hydrophobic polymer molds made of poly(dimethylsiloxane). The high solids loading of the suspension and the soft elastomeric nature of the mold inhibit crack formation during drying and ensure that the ceramic parts can be demolded without damage. High quality line patterns with an aspect ratio of 0.5 and a pitch of less than 3 micrometer were fabricated. A processting route for generating small ceramic features of different materials than the employed substrates is also presented. For making these selective coatings the ceramic substrates were structured with photoresist by lithography. A pattern of 5 micrometer wide lines of electroceramic material was successfully prepared on a sapphire substrate