The nanoscopic electrostatic drive (NED) actuators reduce the electrode spacing needed to generate electrostatic forces to a few hundred nanometers while achieving deflection movements of more than 100 micrometers.
"Large deflections are normally only possible with larger electrode distances and, therefore, with very high drive voltages," said Professor Harald Schenk, director of the Fraunhofer IPMS, in a statement. "In NED actuators, however, electrostatic forces are diverted into lateral forces. These transformed lateral forces produce a quasi-static deflection within a bending beam, which can be substantially larger than the electrode spacing. As a result, our actuators provide higher performance while using much less energy."
Fraunhofer has not revealed the material system in use or the voltages required. However it has said that the MEMS-based bending actuators are made with surface micromachining (V-NED) or bulk micromachining (L-NED) on or within silicon wafer substrates and that they work similarly to bimorph actuators such as those based on piezoelectric or thermomechanical effects. NED actuators are CMOS compatible, Fraunhofer said.
Applications could include optical zoom lens systems, micropumps, microvalves for microfluidics and loudspeakers for earphones and hearing aids.
Fraunhofer IPMS will present for the first time functional NED demonstrators and prototypes at Photonics West 2017 running from January 30 - February 2, 2017 at the Moscone Center in San Francisco. Professor Schenk is presenting an invited talk "A Contribution of the Expansion of the Applicability of Electrostatic Forces in Micro Transducers" on January 30, 2017 at 1:30pm.
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