Micro Snap-Fits for Latching 3D MEMS Assemblies

Abstract

This paper reports the design, fabrication and demonstration of micro-scale mechanical latches (micro snapfits) for assembling 3D micro-structures from 2D patterned precursors. The latches consist of pairs of pointy arrowheadlike features mounted on cantilevers, on one membrane, and corresponding slits in the mating membrane. As the membranes are pushed together, the cantilevers bend elastically and squeeze the arrowhead tips through the slits to latch onto the back side of the mating membrane. The latches are reversible, enabling reconfigurable assembly. They are also designed to have no backlash, enabling precise positioning of the assembled structures. An analytical model of the latches was used to design the profile of the arrowheads subject to the geometrical constraints imposed by the alignment system. The micro snapfits were demonstrated by assembling a corner-cube from two folded flat panels with the substrate serving as the third side. Copyright © 2010 by ASME.