This thesis presents a comprehensive analysis of various passivation layers for interdigitated electrodes (IDEs), focusing on their fabrication, behavior under varying environmental conditions, and their influence on performance and longevity. The primary aim is to determine the most effective passivation techniques to enhance the stability and reliability of IDEs in biomedical applications, particularly in neuroprosthetic devices. IDEs are fabricated using photolithographic techniques in a controlled cleanroom environment, both with and without passivation layers such as SU-8, Silicon dioxide, and Silicon nitride of varying thicknesses. The experimental setup involves electrochemical impedance spectroscopy (EIS) to measure impedance in different media, such as air, deionized water, tap water, and saline solutions, to assess the effectiveness of these passivation layers.