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In dieser Dissertation wurden Zuverlässigkeitsaspekte der NED-Aktoren betrachtet und ihre Langzeitstabilität untersucht. Die Langzeituntersuchungen an einzelnen NED-Aktoren haben gezeigt, dass insbesondere große elektrische Felder zur Verkürzung der Lebensdauer der Aktorik führen können. Elektrische Felder beschleunigen Oxidation der NED-Siliziumelektroden. Dabei wurden zwei unterschiedliche Oxidationsmechanismen beobachtet: die anodische Oxidation von Siliziumelektroden im Isolatorbereich und die feldemissionsunterstützte Oxidation. Die beiden Degradationsmechanismen begünstigen das Wachstum des Siliziumoxides an Siliziumelektroden und resultieren in der Veränderung der Oszillationseigenschaften der NED-Aktoren mit der Zeit. Weitere Untersuchungen an den NED-basierten Anwendungen – Mikrolautsprecher haben verdeutlicht, dass solche Faktoren wie Feuchtigkeit die Degradation am meisten forcieren. Durch Passivierung der Aktoren, wobei sie z. B. mit Aluminiumoxid im ALD-Verfahren verkapselt werden, können unerwünschte Degradationsmechanismen deutlich verlangsamt werden. Durch eine geeignete Materialwahl bei der Verkapselung kann sogar gleichzeitig die Effizienz der Aktoren verbessert werden.
Recent advances in additive manufacturing offer promising opportunities for the fabrication of structures on existing micro-(opto-acoustic )electro-mechanical systems, i.e., chips. This is of particular significance in research and development due to the adaptability and adaptation speed of additive manufacturing. These advantages provide the ability to individualize the fabrication of structures and to enable the rapid prototyping approach. The combination of additive manufacturing on chip already enables current research, especially in photonic and microfluidic fields. Despite this, additive manufacturing on chip has never been applied to acoustic sensors or micro-positioning chips. Such devices could benefit from the mentioned advantages, especially for the fabrication of beam shaping waveguides, packaging, grating and end effector structures. Additive manufacturing by two-photon polymerization lithography gathers interest in industry and research due to its capabilities for the fabrication of structures with minimum feature sizes beyond the diffraction limit. The objective of this work is the investigation of additive manufacturing on chip by two-photon polymerization lithography at the example of an acoustic sensor and a micro-positioning chip. One of the greatest challenges is posed by the optical, thermodynamic, adhesion and alignment effects, which are introduced to the fabrication process by these complex substrates. Optical and thermodynamic models were established, and simulations were performed, culminating in a compensation method to address these effects, which was verified by parameter studies. The substrate alignment was investigated via optical technique, resulting in the development, manufacturing and verification of a novel alignment upgrade to the fabrication system employed in this work. The influence of process materials posed another challenge, as they led to chip performance alterations and restrictions. Chips treated with these materials were characterized, e.g., using high frequency optical microphones. Owing to the high precision of the alignment upgrade and the compensation method developed in this work, additive manufacturing on chip using two-photon polymerization lithography on the investigated devices was reported for the first time and presented for expedient examples, e.g., waveguides, end effectors and gratings. The residue contamination was determined as the main origin of the exhibited performance issues. Development strategies were recommended for further research, to enable additive manufacturing on chip insensitive to residual materials. In this work, the requirements for additive manufacturing on chip were illustrated and the fundamental arrangement to enable the rapid prototyping approach as well as design individualization were demonstrated. The compensation methods developed in this work facilitate upcoming research on desirable chip types that form the basis for optical and microfluidic applications.