Global communication, exchanges of pictures and films, intelligent and connected devices: increasing data volumes produced everywhere. This also raises the need for storage capacity. Magnetic materials could play a key role in the future in the development of novel storage devices and more efficient microelectronic components. Especially ferromagnetic thin films are of interest in this regard which are currently used in MRAMs, i.e. magnetic data stores. These layers are characterized by the spontaneous formation of regions of different magnetization directions in the plane of the layers, so-called domains. The structures of these domains depend on the dimensions and shapes of a layer. It has not been possible so far, however, to manufacture magnetic layers in a simple process in such a way that the individual domains have a given size and direction. KIT scientists of the Institute for Applied Materials - Applied Materials Physics (IAM-AWP) have found a way to influence the domain structures of magnetic thin films in a simple and specific way. For instance, they calculated and measured the way in which the domain structure of a layer 20 x 20 µm in size and 200 nm thick is produced. The scientists generated slots in the magnetic layer by microstructuring. Given proper arrangement, length and width of the slots, the surface area of the domains can be maximized by magnetization devices parallel to the slots. The areas of the domains with vertical magnetization are minimized.A preferred direction of domains is advantageous in developing electronic components as small and as efficient as possible. In the future, these could contribute to the optimization of electronic components, such as inductors. The KIT technology also allows novel domain structures to be designed, such as radial alignment in ring-shaped kernels. In the future, this development could also be used to produce polarized electrons for spintronic devices.