A MEMS based electrochemical seismic sensor

This paper presents a micro-electro-mechanical system (MEMS) based electrochemical seismic sensor where insulating spacers and sensing electrodes were contained in a plexiglass tube filled with an ion-rich electrolyte solution. Sensing electrodes and insulation spacers were fabricated based on MEMS processes and assembled by adhesive bonding in a layer-by-layer manner. The device performance was first characterized in a customized experimental platform, with a quantified bandwidth of 0.2-5 Hz and a linear voltage output as a function of the input vibration amplitude. A random-vibration testing in the laboratory environment was conducted, where response correlations among seven devices were calculated as 0.976±0.017, suggesting high device repeatability. This newly proposed seismic sensor may function as a promising seismic motion detecting device in the field of geophysical prospecting where low-frequency seismic motion detection is requested.