Robust latching MEMS translation stages for micro-optical systems

A multi-state latching translation stage is demonstrated using microelectromechanical systems technology. The mechanism is fabricated in bonded silicon-on-insulator material with an 85 µm thick bonded layer, by single-layer patterning, deep reactive ion etching, undercutting and metallization. The table position can be continuously adjusted by electrothermal buckling mode actuators or latched into a discrete set of states using a rack-and-tooth mechanism driven by electrothermal shape bimorph actuators. A travel range of more than 100 µm and a latching precision of 10 µm are demonstrated. The load carrying capacity of the device is in the milligram range, corresponding to the mass of many microoptical components.