Cochlear implants restore hearing to many people around the world. These devices are hand-made and have limitations in terms of sound quality. The maximum number of electrodes at present is 22 and this means that the sound spectrum is divided into 22 blocks. Furthermore, the breadth of the implant limits penetration and thus lower frequencies are lost. Silicon based technology enables an increase in the number of electrodes and also a reduction in the cross-section of the probe. This will improve sound quality and reduce risks of damage during insertion. This paper shows the development of new technologies to improve the quality of cochlear implants. These involve a move to polymers which make use of silicon-based technology in their manufacture.