MicroXY stages with spider-leg actuators for two-dimensional optical scanning

We propose a micromachined XY stage consisting of eight ‘L’ shaped (spider-leg) stage-suspension springs and rotational comb-drive actuators for two-dimensional microlens scanner. The new design features rotational comb drives that are attached to the rotational hinge, where the movement of the comb drive is constrained to rotation only. The mechanism ensures stable and satisfactory in-plane motion. We designed a microlens-type optical scanner utilizing the spider-leg actuator. Silicon was used as a lens material because it is mechanically stable and optically transparent to infrared light around the wavelength of 1.55 μm. The microlens scanner was fabricated by lens-profile-transferring to the structural layer of a silicon on insulator (SOI) wafer by the reactive ion etching (RIE) from thermally reflowed photo resist (PR) and continuing two deep RIEs. The XY stage moved more than 55 μm independently in the X and Y directions with applied voltage of 40 V. The optical coupling loss between the faced microlens-pair showed 10.5 dB with microlenses of a 1 mm diameter, which can be applied to the optical cross connect (OXC).