In-plane comb-drive actuator with high frequency-displacement product for micro-optical bench applications

This work reports the design, implementation and testing of an in-plane comb-drive actuator achieving a travel range of 17.8 μm at a resonance frequency of 26 kHz, and monolithically integrated with a vertical micromirror. The product of the travel range and the frequency is 463 μm.kHz, indicating the maximum linear velocity of the micromirror, is the highest of a MEMS in-plane actuator reported under atmospheric pressure, to the best of the authors' knowledge. The design is fabricated using the DRIE technology on an SOI wafer and tested optically by counting the interferometric fringes formed between the micromirror surface and a standard single-mode fiber at the wavelength of 1550 nm.