Chair Microsystems and Biomedical Engineering

Prof. Dr. Jan Mehner

Phone +49 (0)371 531 24430
jan.mehner@…

http://www.tu-chemnitz.de/etit/microsys

Main research topics

The Professorship of Microsystems and Biomedical Engineering is mainly focused on design, experimental characterization and application of micro-electro-mechanical systems (MEMS), additionally applications of sensors and precision engineering in the field of biomedical engineering completing the working field. Innovative techniques are investigated in order to link mechanics, optics, electrical engineering and electronics for highly integrated smart systems.

• Modeling and simulation of physical domains and their interactions
• Experimental characterization and measurement methodologies
• Sensor and actuator development
• Biomedical application

Extended description of Research topics

Micro systems are key components of complex heterogeneous devices such as automotive products, industrial automation and consumer applications. Academic research and education is strongly related to partners from industry and research institutes.

One of the most advanced topics in the field of design is the challenge to establish fast and precise behavioral models for micro systems and nano systems. Parametric reduced order modeling (ROM) technique, Fig. 1, is the most promising approach to this.

Figure 1: Parametric reduced order modeling.

The technique was expanded to integrate results from ab-initio atomistic simulations for NEMS. The parametric ROM macromodels capture the complex nonlinear dynamics inherent in N/MEMS due to highly nonlinear electrostatic forces, residual stresses, stress stiffening and supports multiple electrode systems and mechanical contact phenomena. Geometrical nonlinearities, such as stress stiffening, can be taken into account if the modal stiffness is computed from the second derivatives of the strain energy with respect to modal coordinates. The ROM technique based on the mode superposition method is a very efficient technique for fast transient simulation of N/MEMS components in order to export macromodels for external system simulators. This advanced design technique is successfully used for instance for the design of the acoustic emission sensor (vibrational sensor) shown in Fig. 2.

Figure 2: Acoustic emission sensor.	Figure 3: PVM-200 vacuum wafer prober.

The Professorship of Microsystems and Biomedical Engineering is equipped with a state of the art characterization lab containing an atomic force microscope (AFM), autofocus topography, dynamics measurement system and different types of interferometrical measurement systems. Fig. 3 shows the currently most advanced tool which is a PVM-200 Vacuum Wafer Prober equipped with a Micro System Analyzer MSA 500 enabling dynamic and topographic characterization of MEMS at adjustable vacuum and thermal interference. The MSA uses laser doppler vibrometry with scanning laser beam and stroboscopic illumination for out-of-plane and in-plane motion analysis respectively. White light interferometry allows topographic measurements in vacuum conditions.

One of the current medical related projects is the research on a catheterless pressure measurement method in the bladder. The measurement system consists of an implantable intravesical capsule that measures the pressure for a period of more than 72 hours. The flexible capsule consists of a MEMS pressure sensor, an EEPROM for storing the measured time and pressure data, a microcontroller and a battery based power supply.