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High-performance ceramics have been firmly established for the manufacturing of tools and components in the modern electronics industry and mechatronics. Various components such as circuit boards, bearings, and sensors benefit from their specific characteristics, such as wear resistance, stiffness, and electrical neutrality. Apart from these advantages, the brittleness and hardness of ceramics turn the mechanical processing into a challenging and difficult task. Against this background, modern laser technologies have already been used to process ceramics for many years, enabling a contactless and wear-free machining. However, regarding high precision applications, for instance, the drilling of micro-holes or the fabrication of well-defined cavities and three-dimensional structures, conventional laser processes reach their limits. Especially due to thermal influences of the laser radiation, brittle edges, stresses, and redeposited layers emerge. Ultrashort pulse lasers enable completely new processing qualities in these fields. The extremely short pulse durations within the pico-and femtosecond range lead to nonlinear absorption mechanisms and an almost athermal material removal. Thereby, dielectric materials can be processed precisely and gently. In the course of a comprehensive process study, the beam-material interactions of ultrashort pulses with ceramics have been investigated. Besides the material properties, the ablation process is influenced by a multitude of laser parameters, such as wavelength, pulse overlap, and fluence. In order to reveal the most important variables, the experiments have been conducted by applying modern statistical methods. Using alumina (Al 2 O 3) as an example, it is shown how different parameter regimes lead to disparate process qualities and efficiencies. The generated models have been used to optimize industrially interesting applications, from the separation of ceramic printed circuit boards to the realization of precise design structures.

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The development of ultrashort pulse lasers has enabled many new process technologies in the past few years. The nonlinear absorption caused by high peak intensities and the nonthermal ablation are two of the most attractive benefits of pulse durations in the pico- and femtosecond regime, which allow for the processing of a wide variety of materials. Even dielectric, brittle-hard substrates can be processed precisely and gently without cracking or inducing stresses. For this reason, the technology is particularly suited to open up new processing possibilities in the field of functional ceramics. These materials offer many opportunities to set up complex microsystems and multisensor systems. However, the options to structure and shape functional ceramics were limited in the past and had to be solved by elaborate mechanical processes so far. By means of ultrashort pulse laser processing, new applications in the fields of precise shape formation and microstructuring of functional ceramics become accessible. In order to reveal and optimize the processes occurring during surface ablation, investigations with different laser systems have been executed and evaluated by applying various characterization techniques. The results show how the properties of the bulk material and the process parameters such as pulse energy, wavelength, and pulse overlap influence the removal rate as well as the material characteristics, for instance, roughness and morphology. Thereby, the attention is focused on the dependence of the process on the pulse duration. In contrast to the homogenous surface profile that is created during picosecond ablation, the femtosecond process exhibits material modifications in terms of melting patterns. This effect is strongly dependent on the pulse duration, the fluence, and the pulse overlap. It leads to an increase in roughness, which affects the precise material removal. Nevertheless, the investigations also show that the material melting can be utilized to achieve a smoothing effect of the surface if the parameters are well adjusted. The experimental investigations result in optimized process strategies to realize user-defined aims like high ablation rates, high accuracy, or low damage.