Under atmospheric pressure, plasma can be produced even in very small volumes with dimensions of just a few micrometers so that the local functionalization of surfaces is possible. Plasma printing is an innovative process for the local modification of surfaces: a structured dielectric forms cavities in which the plasma develops. The typical dimensions of the cavities are from a few tens to a few hundred μm. In addition to the position-specific modification of surfaces, this process also supports structured layer precipitation and functionalization. Numerous functional groups can be impressed on the substrate, similar to a stamp, depending on the chosen to discharge conditions. Suitable substrates include polymers, glass and silicon. Surfaces with any geometries such as arrays of spots, with special surface characteristics such as hydrophilic or hydrophobic properties, or with targeted chemical functionalization can be produced using the plasma printing process.
Local functionalization can be applied for example in the production of surfaces for biomedical applications (biochips, DNA/protein/diagnostic chips) and for subsequent metallization, among other things for the production of interconnect devices, RFID antennas or biosensors. Plasma printing can be realized in a discontinuous or a continuous reel-to-reel process.