A technique for manufacturing a micro-electro-mechanical (MEM) structure includes a number of steps. Initially, a substrate is provided. Next, a plurality of trenches are etched into the substrate with a first etch. Then, a charging layer is formed at a bottom of each of the trenches to form undercut trenches. Finally, a second etch is provided into the undercut trenches. The charging layer causes the second etch to laterally etch foots in the substrate between the undercut trenches. The footers undercut the substrate to release a portion of the substrate for providing a movable structure between the undercut trenches and above the footers.