Mechanical properties of surface microstructures of metal dry bioelectrode

The metal dry bioelectrodes have been developed to measure the bioelectrical signals. In this study, the laser micromilling process as an economical and high efficiency way was proposed to fabricate the metal dry bioelectrodes with surface microstructure array. The measuring principle of material hardness was adopted to characterize the mechanical properties of surface microstructures of metal dry bioelectrodes. Moreover, the compressive strength of surface microstructures of metal dry bioelectrodes fabricated with different scan spacings was discussed, and then the bending strength and insertion performance of surface microstructures of metal dry bioelectrodes were further investigated. The results show that surface microstructures of bioelectrode fabricated using three scan spacings including 100 μm, 150 μm and 200 μm exhibited better compressive performance. When the 100 μm scan spacing was selected, the surface microstructures of metal dry bioelectrodes presented larger bending strength, and it could successfully penetrate the silicon film with a small pressure about 1.48 N.