BSAC Technology Seminar - A Novel Approach for High Efficient Electrostatic Micro/Nano Transducers

Seminar | February 7 | 12-1 p.m. | 490 Cory Hall

 Prof. Dr. Harald Schenk, Director, Fraunhofer Institute for Photonic Microsystems

 Berkeley Sensor & Actuator Center

Electrostatic forces provide excellent scaling behavior that makes them first choice for micro and nano actuation. However, large stroke is at cost of large electrode gaps preventing to make use of this advantage. As a consequence, other driving mechanisms like piezoelectricity or electromagnetism are applied - although integration on wafer scale is often more complex and required materials are incompatible to CMOS-processes.
A new electrostatic actuator class has been developed profiting from high forces at electrode separations of a few 100 nm only and providing several hundreds of nanometer up to 100 µm of deflection. The concept is based on transforming electrostatic forces generated on the surface of a cantilever into a mechanical surface stress resulting in a voltage-dependent curvature of the beam. By suitable designs and fabrication processes a large variety of motion patterns is enabled including bi-directional out-of-plane and in-plane motion as well as membrane deformation. The principle has been investigated by simulation and analytical models and was verified by fabrication and characterization of several types of actuators in SOI technology as well as in surface micromachining technology. The concept provides an extension to state-of-the-art electrostatic actuator technologies. It potentially extends the applicability of electrostatic forces for a large variety of integrated transducers. Several potential application examples, currently under development and evaluation, are given. This includes analog and digitally operated deflection beams, micro pumps, micro loudspeakers and ultrasonic transducers.

 Faculty, Staff, Students - Graduate

  RSVP online by February 6