High precision laser structuring of micro forming tools

Because of the increasing demands for cost-effective and high-precision micro fluidic components the micro hot embossing technology becomes more and more important. An essential element of this technology is the required micro forming tool. The required structural sizes and structure forms as well as the used tool materials limit the application of conventional processes like milling. The structuring with laser offers an alternative method because the material removal with a laser beam allows the manufacturing of very fine structures also in hard and brittle materials. For initial experimental investigations a high strength ceramic material (silicon carbide) was used to produce forming tools for micro fluid components. It succeeded to produce structures with dimensions smaller than 20 µm and in a depth of 200 µm. The evaluation showed very good surface qualities (roughness below RZ 2.55 µm) and a high geometrical accuracy. First replication experiments in PMMA (polymethyl methacrylate) and polycarbonate also show good results and comparable structure qualities.