Cochlear Implant Electrode Improvement for Stimulation and Sensing

Electrode array, an important component of the Cochlear Implant (CI) design holds a key position in restoring the hearing process to the deaf patients. It represents a direct interface between the auditory nerve (biological tissue) and the electronic system of the CI. Electrode arrays are available in different design, material, shape and size depending upon the requirement and the application of the device. The traditional fabrication method of the device restricts the electrode usability and its performance. In this chapter we investigate and explore capable materials for CI electrode array fabrication used for stimulation purposes. Here we discuss the CMOS compatible electrode material Titanium Nitride (TiN) as one of the possible candidate for electrical stimulation in electrode array. Electrical characterization in terms of current density, Electromigration, Impedance, and Temperature Coefficient of resistance (TCR) for different materials were performed to demonstrate electrical compatibility. Micro-fabrication process for electrode array is discussed which exhibits the future advantageous manufacturing technique in comparison with the traditional method used nowadays.