Low-cost non-etched silicon neural probe

This paper describes the fabrication of silicon neural probes based on low-cost semiconductor technologies, such as photolithography, thin-films deposition and blade dicing. Each 8 mm long fabricated neural probe has 13 platinum recording sites (microelectrodes) with different dimensions, ranging from 50 × 50 μm 2 to 300 × 300 μm 2 . The platinum microelectrodes impedance were characterized through electrochemical impedance spectroscopy with results ranging from 5 kΩ to 600 kΩ at 1 kHz. Local field potentials were recorded when performing in-vivo electrophysiological recordings on an adult mouse. The results demonstrate the functionality of the neural probe, by acquiring local field potentials activity even with a microelectrode area of 50 × 50 μm 2 . Moreover, the results suggest a robust and versatile fabrication process avoiding etching processes.FCT with the project OpticalBrain, reference PTDC/CTM-REF/28406/2017, by FEDER funds through the COMPETE 2020 - Programa Operacional Competitividade e Internacionalizacão (POCI