3D printed stainless steel microelectrode arrays

This paper reports the design and fabrication of highdensity high-aspect-ratio stainless steel microelectrode arrays (MEAs), 3D printed using micro laser sintering from stainless steel powder with 5μm vertical and 30μm lateral resolution. The electrical and mechanical characteristics of printed 316L and 17-4PH steel are investigated, measuring sintered metal densities greater than 95% of bulk and a 4-point electrical resistivity of 114μΩ-cm and 95μΩ-cm, respectively. One hundred element (10 by 10) MEAs with 1.5mm tall tapered electrodes are realized via interlocking sacrificial supports, which protects electrode geometries during manufacturing, thus enabling customizable 3D microelectrode arrays applications such as biomedical implants.