System for 3D femtosecond laser-based micromachining

• Subject Area: Materials Science
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537273289

The precise 3D micromachining of complex glasses and glass ceramics represents an internationally important research area for microsystems technology, but also for the state of Thuringia in terms of its regional innovation strategy. The field of application ranges from microsensors and actuators, optics and precision metrology to lifesciences, energy harvesting and quantum technologies. Reproducible and precise glass micromachining is still a major challenge and is carried out using, for example, fluorine plasma-based processes. However, the creation of 3D structures in glass by these methods is currently only possible to a very limited extent and is disproportionately elaborate. The application therefore aims to acquire a system for resource-saving, fluorine-gas-free and efficient 3D micromachining of glasses and glass ceramics. Using a focused femtosecond laser, glasses can be modified in a highly localized area. 3D processing is performed by guiding the laser focus in 3D, primarily focusing on so-called "selective laser(-induced) etching" (SLE) and hermetic welding of glasses. Secondary are local refractive index modifications, selective material ablation (e.g. metal thin films) and two-photon polymerization (2PP). This allows complex and novel 3D functional structures to be created, which cannot be produced with the processes currently available at the TU Ilmenau, or only with disproportionately high effort. Last but not least, the facility thus also permits new approaches in the design and construction of interdisciplinary microsystems, which are worth exploring. The combination of this laser-based 3D micromachining with the existing research work in the field of plasma-based glass microstructuring, photostructurable glasses and an electron beam-based glass nanostructuring, for which a patent has recently been filed, allows innovative degrees of freedom and thus the implementation of new types of interdisciplinary and cooperative research projects at the TU Ilmenau and the Microsystems Technology Group. The facility will be operated in the clean room laboratory of the Microsystems Technology Group in close proximity to the Center for Micro- and Nanotechnologies (DFG Core Facility) to implement cooperative and interdisciplinary research work in a controlled laboratory environment, which also provides all peripheral technologies. Furthermore, a seamless integration into the ongoing research topics is guaranteed. Of course, the facility will be available for in-house and also external research collaborations.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Anlage zur 3D-Femtosekundenlaser-basierten Mikrobearbeitung
• Instrumentation Group: 5740 Laser in der Fertigung
• Applicant Institution: Technische Universität Ilmenau
• Leader: Professor Dr.-Ing. Steffen Strehle