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Novel polysilicon grating switches are demonstrated, consisting of an optical grating suspended on a moving platform above a waveguide. Electrostatic attraction pulls the grating into close proximity to the waveguide, ejecting light out of the waveguide plane. The switches move only 0.9 to 1.4 $\mu \text{m}$ , and have MHz mechanical resonant frequencies, making them robust to mechanical vibration and shock. These switches enable a new mode of LiDAR imaging; by creating a focal plane array of switches, and coupling it with a standard camera lens, the LiDAR beam can be scanned across the scene with high speed and arbitrary pattern. Both time of flight and coherent ranging techniques are compatible with this approach. We have demonstrated a $10\times 10$ pixel array of these switches in a LiDAR system, collecting 3D raging data at up to 15 meters away and 5 frames per second, over a 1 degree field of view with 0.1 degree resolution. Additionally, we have shown the switches to be robust, efficient, and reliable, actuating at 15 Volts, with speeds faster than $4~\mu \text{s}$ , for over 9 billion cycles without degradation or failure. [2020-0132] [ABSTRACT FROM AUTHOR]

We have designed, built, and tested novel low-power (less than 10 nW) resonant acceleration switches. The switches respond to vibration at specifically designed frequencies between 30 and 1000 Hz by resonating with sufficient displacement to close an electrical contact and consume power only while vibration is occurring. A rotational design avoids switch closings from DC acceleration, and the quality factor, adjustable between 102and 105by tuning the vacuum level, sets the resonant detection threshold. The design includes electrostatic combs for self-test and frequency tuning (up to several Hz), compliant contacts to reduce squegging and contact damage, and ruthenium-coated contacts for improved reliability. Fabrication is accomplished with deep reactive ion etching at up to 50:1 aspect ratios, HF vapor release, and XeF2frequency trimming (up to 30% of the as-fabricated frequency). Testing with vibration recordings played back through a shaker table demonstrates that the switches correctly identify a target without any false alarms. [2018-0061] [ABSTRACT FROM AUTHOR]

We have designed a novel microelectromechanical systems (MEMS) resonant acoustic wake-up switch which is actuated by ambient sound waves, using zero power while waiting for a signal at its resonant frequency and less than 10 nW when the signal is detected. The system uses a battery to charge a capacitor through MEMS switches activated only by the target signals. The sensor is of rotational design allowing it to be insensitive to linear vibration and static gravity forces. Analysis and experimental results maximizing the Q of these resonators in air are presented. A simple, novel fabrication process is presented which uses silicon-on-insulator bonded wafers and still provides metal–metal electrical contacts. These devices have successfully detected 80-Hz sound as low as 0.005 Pa rms (48-dB SPL // 20 $\mu $ Pa) from a generator. [2017–0282] [ABSTRACT FROM AUTHOR]