Fabricated using silicon-oninsulator micromachining techniques, Imec’s latest actuator operates with ultralow power. It’s also watertight, making it viable for use in in-vivo biomedical devices and other applications that need to combine a long autonomy with small batteries (see the figure).
The prototype integrates a micro needle, which is steerable by the actuator, and combines a fairly wide range of ±50 µm with a force of ±195 µN, allowing it to position in-vivo electrodes. It works at 11 V, which Imec says is three times lower than the operating voltages of currently available actuators, and consumes less than 100 nW.
Described as an electrostatic inchworm actuator, the component employs six arms that selectively latch, unlatch, and drive: four for latching and two for driving functions. Additionally, the package’s flip-chip mounted glass cap and hydrophobic surface treatment prevent water ingress.
As an example application, the actuator could be used to accurately control the position of micro-needles used in brainmonitoring tasks. This is necessary to reach the correct groups of neurons for the specific disorder and to get near the neurons for a better signal-to-noise ratio.