Abstract
This paper presents a 5-axis motion sensor that can detect 3-axis acceleration and 2-axis angular rate capacitively. This sensor is fabricated by SOI bulk-micromachining, and is sealed vacuum by anodic bonding and activation of the non-evaporated getters. By applying Z-axis reference vibration of a proof mass with an electrostatic force at resonant frequency, 5-axis motions can be detected capacitively at non-resonant detection mode. How the resonant frequency of driving direction and detection direction of this sensor changed by size of the weight, beam width, beam thickness and beam length, was clarified. Three samples were made by this design method, and acceleration characteristic and angular rate characteristic were measured, and the effectiveness was shown.
