FABRICATION METHOD FOR A BIO-INSPIRED RESONANT MEMS ACOUSTIC SENSOR

Abstract

The Sensor Research Lab at the Naval Postgraduate School (NPS-SRL) successfully developed a directional, resonant Microelectromechanical (MEMS) acoustic sensor. Currently, the sensor is designed at NPS-SRL, but its manufacturing is outsourced, which creates a logistical delay and design restrictions that are progressively limiting the development and evolution of the NPS sensor. To overcome these limitations, this study proposes a design approach and then executes a fabrication method using the current resources, materials and facilities available at NPS-SRL. The method offers potential new users a step-by-step process that results in a set of acoustic sensors in a single silicon wafer. The design of the process has mitigation measures that increase the survivability percentage of the acoustic sensors by adding redundancy in the design, which allows multiple acoustic devices of the same characteristics in one wafer. Then the characterization of the fabricated acoustic sensors was performed through laser vibroanalysis to obtain the frequency response. These results were compared with finite element simulations to validate the results. The success of this method reduces the current fabrication times and costs, enhances the research alternatives for future users, and expands the potential new applications for the NPS-SRL acoustic sensor.