Today's devices for high-voltage applications usually require sophisticated terminations at the edge of their active regions, so that a breakdown can be avoided in case of a switch-off. The thesis begins with a brief discussion about todays concepts for edge terminations and their problems represented by simulation results. Beside planar concepts, vertical ones by using trench structures, e.g. mesa- or trench edge termination, are possible as well. The main focus of this work is the development of a process for the generation of vertical edge termination structures. The high demand on quality and geometry exclusively leads to the use of anisotropic wet etching processes with alkaline solutions. Beside the discussion of the theoretical fundamentals, a detailed process investigation by using modified and unmodified alkaline solutions may provide new data and insights on a topic which unfortunately has undergone stagnation in research in the last 10 years. Analytical methods for continuous process monitoring, characterization and quantification of the etching solution are briefly discussed. The result leads to a description of the surface tension of a water-based solution, as well to a detailed investigation of this parameter for different alkaline solutions, by using the novel bubble pressure method. The obtaining results show a direct dependency of the solutions surface tension on the orientation-dependent etching characteristics. After optimizing the wet-chemical etching process conditions for the generation of vertical trench structures, further processes, e.g. the total trench-filling with suitable high voltage-resistant materials, are investigated. Beside the discussion of the material properties, different filling methods are tested and their quality assessed.