Patent ID: 7767483

Claim:
A method for fabricating a dual-suspension system for MEMS-based devices comprising the steps of: etching the geometry of an upper spring system, a lower spring system, and a proof mass into a substrate, the substrate initially comprising: a handle wafer having a first side and a second side, a first layer of oxide covering the first side and a second layer of oxide covering the second side, and a first layer of silicon covering the first layer of oxide and a second layer of silicon covering the second layer of oxide, wherein the geometry of the upper spring system, the lower spring system, and the proof mass are etched into each of the first layer of silicon and the second layer of silicon, the regions of the substrate opposite the proof mass and adjacent to the upper spring system and the lower spring system defining a support structure; applying a protective barrier to cover at least the exposed portions of the first layer of silicon; etching through portions of the protective barrier and the handle wafer to define the shapes of the upper spring system, the lower spring system, and the proof mass; removing the remainder of the protective barrier; and removing the first layer of oxide from the areas in contact with the upper spring system and removing the second layer of oxide from the areas in contact with the lower spring system.