Tuning of Microfabrication Parameters for Improving Performance of Microelectrodes in Neural Prosthetics

TL;DR

This study investigates how microfabrication process parameters affect the surface morphology, corrosion rate, and electrochemical performance of platinum and glassy carbon microelectrodes for neural prosthetics, aiming to enhance stability and efficacy.

Contribution

It provides a detailed analysis of the relationship between fabrication parameters, surface topography, and electrochemical performance of neural microelectrodes, introducing optimized fabrication insights.

Findings

Surface roughness correlates with corrosion rate.

Process parameter variations influence surface morphology.

Electrochemical efficacy depends on fabrication-induced surface features.

Abstract

Neural prosthetics are typically situated in an aggressive, biochemical environment that requires materials with superior stability and performance. These probes have dual functionalities of recording and stimulation. The material stability is defined by the ability of these probes to withstand the operating conditions throughout billions of cycles of electrical modulations. On the other hand, performance is measured by the electrochemical response of the microelectrode materials. In this paper, microelectrodes made of two material systems; namely, platinum and glassy carbon thin-films, supported on a flexible substrate are fabricated and investigated for the correlation between process parameters and the electrochemical efficacy of the neural interfaces. The resulting neural electrodes were used to investigate the interrelation between process parameters, surface morphology and topography of platinum and glassy carbon films using scanning electron, and atomic force microscopies. The results show that changes in surface topography and the rate of corrosion are relative to variations in the process parameters. Furthermore, the results indicate a general trend between surface roughness and corrosion rate, in which the increase or decrease of the former corresponds to a similar change in the latter.