An Electrochemical Microbubble-Based MEMS Pressure Sensor

Abstract

A novel pressure transducer concept is introduced in which external pressure variations induce changes in the volume of a trapped microbubble (μB) in an electrolyte solution. These volumetric changes are monitored by electrochemical impedance-based measurements and may be used for pressure tracking applications. Microbubbles are nucleated on-demand by electrolysis within a confinement chamber with high precision (measured size RSD ~1%). This pressure transducer concept was developed specifically for operation in liquid environments and features biocompatible construction, small footprint (<;0.1 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), and low power consumption (<;1 nW). This combination of features is ideal for in vivo pressure monitoring applications.