This proposal addresses fundamental issues regarding ion-beam nanostructuring of monocrystalline zinc oxide (ZnO), which is a novel semiconductor with great prospects in areas such as photovoltaics, photonics and spintronics. The use of ion beams in semic onductor technology has been a success story since the early 1960?s for controlled doping, and currently, we are entering a new exciting era where ion beams are exploited for nanostructuring of materials utilizing the inherent dimensions of ion-induced at omic collision cascades (typically, from a few nm to ~1000 nm).State-of-the-art epitaxial ZnO films grown by Metal Organic Chemical Vapour Deposition (MOCVD) as well as bulk ZnO samples will be exposed to energetic ions in order to modify electrical, opt ical and magnetic properties. In particular, the role of vacancy clusters (especially zinc vacancies), which occur with dimensions on the nm scale, and their interaction with dopant elements and impurities like hydrogen and transition metals will be targe ted. In fact, 'tuning' of these vacancy clusters may be decisive to accomplish controllable p-type doping by ion implantation. A cross disciplinary approach is taken for sample characterization involving structural, electrical, chemical and optical techni ques.The project is planned for 1 PhD student and excellent experimental facilities exist at MiNaLab in Oslo for the work. Further, the project comprises extensive collaboration with leading international research partners.