Array-wide uniform PEDOT:PSS electroplating from potentiostatic deposition.

Electroplating of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is important in many neuroelectronic applications but is challenging to achieve uniformity on large-scale microelectrode arrays (MEA) using conventional galvanostatic methods. In this study, we address this challenge through a potentiostatic method and demonstrate highly uniform electroplating of PEDOT:PSS on MEA with more than one hundred electrodes, all at cellular sizes. The validation of this approach involves comparisons with galvanostatic deposition methods, showcasing unparalleled deposition yield and uniformity. Systematic electrochemical characterizations reveal similarities in structure and stability from potentiostatic deposited coatings. The advances developed here establish the potentiostatic method and detailed process to achieve a uniform coating of PEDOT:PSS on large-scale MEA, with broad utility in neuroelectronics.