Microplasma stamps : an atmospheric pressure plasma source for the area selective modification of surfaces The patterned treatment of surfaces is of growing interest for a large range of applications in the fields of life sciences and polymer electronics. Microplasma stamps are based on the principle of dielectric barrier discharges and represent a powerful tool for the area selective modification of various surfaces by the use of atmospheric pressure microplasmas the so called plasma printing. This process integrates the surface modification and lateral microstructuring within one process step. In the present work two different microplasma stamp concepts and their processing are described. In contrast to previous attempts microplasma stamps use a patterned dielectric barrier made of polydimethylsiloxane which enables a good adjustment to wavy corrugated and rough surfaces. The microplasma is generated in cavities which are formed temporarily by compressing the substrate to be treated area selectively and a so called plasma stamp. Thus a well controlled spatial extension of the plasma is assured. For the generation of the structured PDMS dielectric barrier an improved method for the double sided moulding of PDMS has been developed as well as a method for the fabrication of flexible master structures made of the negative working SU 8 photoresist. The microplasma stamp designs are compared to each other and characterized in detail in an experimental series and by simulations using an SIPDP and FEM model. The characterization covers the influence of variations concerning the design of the microplasma stamp the electrode and the cavity as well as the required compression force on the ignition voltage and the deformation of the cavities. To achieve additional information about the effect of the plasma generated in the cavities of the microplasma stamps on the surface treatment an additional SEM and EDX analysis of the mark left by the plasma in the treated areas as well as the distribution of the generated functional groups has been conducted. Based on the results a scaling up has been carried out which presents the applicability of microplasma stamps for the treatment of surfaces in various sizes and forms. As applications microplasma stamps have been successfully applied to the areaselective treatment of polypropylene prior to the electroless deposition of nickel and the peptide synthesis. This offers good prospects for a future application of microplasma stamps as a suitable process tool for the area selective plasma modification of various surfaces at atmospheric pressure.