Reduced formation of asperities in contact micro-structures

摘要

A device comprising movable micro-structures configured to contact a substrate is disclosed. The substrate has a metal-insulator-metal construction with an upper metal layer and an insulator being patterned to provide substrate contact regions to a lower metal layer. The micro-structures have metal under layers for providing ribbon contact regions and non-contact regions. In use, a bias voltage is applied across the micro-structures and the top metal layer of the substrate causing the micro-structures and the substrate to contact through the contact regions. During contact, the contact regions are maintained at a potential that is substantially less than the applied bias voltage, thereby reducing the formation of asperities and/or sticking between contacting parts. The micro-structures are preferably ribbon structures in an optical MEM device configured to modulate light.