A novel MEMS omnidirectional inertial switch with flexible electrodes

A novel MEMS omnidirectional inertial switch was designed, simulated and fabricated. The switch is composed of three main parts, the proof mass, the axial flexible electrode and four radial flexible electrodes. It introduces the flexible electrodes to form a dual mass-spring system. The switch has omnidirectional sensitivities in a half sphere. When any acceleration, over the threshold value in radial or/and axial direction, acts to the switch, the switch will turn on. Also, the switch has the enhanced contact effect. Dynamic simulation results based on FEM confirm that the contact effect is improved by this new design compared to that of traditional inertial switch. The contact duration is prolonged under the shock loading, and the bouncing effect is alleviated. The switch has a 6-layer structure, which is manufactured based on non-silicon surface micromachining technology. The tests have been done and the results coincide with that of the simulation.