Research objectives and content The aim of this project is to combine the advantages of helium surface scattering with recent developments in atom optics to construct the first ever microscope with an atomic probe. A helium atom microscope with its neutral, low energy beam would be a completely new experimental technique for surface science with a wide range of applications. For example in the investigation of reaction processes with light adsorbates or in examining the surface topology of corrugated insulating materials such as polymers. The imaging principle in the proposed helium microscope has two crucial novel components: An ultrahigh performance helium beam source and an atom focusing mirror, which forms the microprobe by focusing the beam onto a sample. The expected result of the project is the completion of a prototype instrument with a resolution in the nanometer regime. Training content (objective, benefit and expected impact) MPI/Strvmung is the worlds largest molecular beam group. The implementation of a novel beam source in a helium microscope will give me the best possibilities for benefiting from the expertise in the group in acquiring new skills in theoretical and technological aspects of molecular beam dynamics. Furthermore I will benefit from being in a group with strong activities in many surface science fields.