Microneedle-based electrodes with integrated through-silicon via for biopotential recording

The fabrication of a novel ultrasharp silicon microneedle array for use as a physiological signal monitoring electrode is described. This work uses anisotropic potassium hydroxide wet etching and double-sided wafer patterning to simultaneously create a microneedle on the front side of the wafer, and a through-silicon via from the back side. This technique eliminates the limitations associated with other approaches that are used to create front-to-back electrical contact. Wearable electrode prototypes have been assembled using these arrays, and electrocardiography (ECG) recordings have been carried out to verify the functionality of the technique. (C) 2011 Published by Elsevier Ltd.