Applications of Nanowire Enabled Micro Opto-Thermal Actuation

Optical actuation for MEMS takes advantage of directly coupling of energy into selected device areas without any electrical interconnects as required in integrated electrostatic and piezoelectric actuation. In opto-thermo-mechanical actuation, light incident onto the structures is absorbed and converted to heat via photon absorption. Here, we realized linear, high efficiency and broad-band optical actuation for circular Si/SiO2 membrane resonator with integrated vertical silicon nano-pillar photonic crystal arrays. The first-ever nanopillar membrane acoustic speaker, using nanoscale photonic crystal optical absorbers for thermo-mechanical excitation of speaker membrane, is demonstrated. Moreover, our device has a very high surface area-to-volume ratio, enabling DNA sensing of femtomolar concentration. Femtomolar concentration DNA detection is important as this is the concentration needed for early-stage cancer and bacterial infection diagnosis application. Our method represents a mass-based platform technology that can sense molecules at low concentrations.