The design, simulation and fabrication of a novel horizontal sensitive inertial micro-switch with low g value based on MEMS micromachining technology

A horizontal sensitive inertial micro-switch with low g value is proposed in this paper. It was simulated using ANSYS software and fabricated by MEMS micromachining technology. It consists of three parts: a suspended thick proof mass as a movable electrode, two novel elastic fixed beams as stationary electrodes to prolong the contact time and a barrier system, which constrains non-sensitive direction movement and eliminates reverse impact. The relationship between the threshold acceleration ath and the intrinsic frequency ω0 is discussed in a theoretical analysis and finite element simulation. The thickness of the proof mass (H) and the width of the springs (k) were designed to be variable to meet the requirement of the application environment. Two novel elastic stationary electrodes were designed specially to improve the contact effect. The fabricated micro-switch was characterized by a standard dropping test. The work frequency is about 33.3 Hz and the threshold acceleration of the sample is about 38g, which meet the simulation value very well. The response time was about 10−4 s and the contact time about 200 us.