A new symmetrical beam-mass structure for accelerometers by anisotropic etching without convex corner compensation

This paper reports a new symmetrical beam-mass structure for sandwich capacitive accelerometers. The single-wafer fabrication of the symmetrical double-sided beam-mass structure in which eight straight beams are connected to the corners of the proof mass is accomplished only by anisotropic wet etching of a (100) wafer without convex corner compensation. Different measuring-range accelerometers can be got by controlling the thickness of the spring beam. A packaged sensor with 140 mum beam thickness is measured by a dropping hammer system. The sensitivity is 58 muV/g for a 5000 g shock acceleration under 5 V power supply.