Upside-down Carbon nanotube (CNT) micro-electrode array (MEA)

A novel fabrication process for CNT micro-electrode arrays (MEA) integrated on stretchable Polydimethylsiloxane (PDMS) membranes is presented. The new process flow overcomes the problems encountered in previous reports. In the process flow presented in this paper, Carbon nanotubes (CNT) electrodes are embedded on the backside of a freestanding membrane using a novel fabrication technique. This upside-down CNT MEA consists of micro-electrodes with an area of 110 μηI2 covered with Cobalt-grown CNTs. The recorded electrochemical impedance values confirm the effectiveness of the proposed design: at 1 kHz the fabricated CNT-MEA electrodes show a reduction of the overall impedance by 95 % in comparison to benchmark TiN electrodes. CNT-MEA impedance is 240 kΩ against 2.2 MΩ of the TiN MEA. The quality of the CNTs was assessed with Raman spectroscopy and the biocompatibility of fabricated CNT-MEA device is demonstrated by the plating of human pluripotent stem cell-derived cardiomyocytes on the CNT electrodes.