This chapter explores the evolution of cochlear implant (CI) technology, focusing on implant architectures, materials, and manufacturing techniques in relation to device reliability and biocompatibility. It compares two main implant designs—modular titanium-based casings and monolithic titanium–ceramic casings—highlighting differences in structure, functionality, and manufacturing complexity. Special attention is given to ceramic materials, particularly high-purity alumina and zirconia, due to their mechanical strength, biocompatibility, and radio frequency transparency. The chapter discusses recent advancements in ceramic processing methods, such as cold sintering and additive manufacturing, which offer promising improvements in implant performance and longevity. It also explores brazing techniques used in component assembly, emphasizing the importance of wetting behavior and interface adhesion. Additionally, the design and fabrication of electrode arrays, essential for effective neural stimulation, are reviewed. Despite variations in design across manufacturers, common technologies such as platinum-based electrodes and polydimethylsiloxane (PDMS) overmolding are consistently employed. This comprehensive overview highlights the interdisciplinary innovations shaping the future of cochlear implant technology.