Apparatus and methods for making cochlear implant electrode arrays

A method of forming an electrode array, comprising the steps of:

• securing a plurality of contact subassemblies to a mold surface at longitudinally spaced locations within a mold solely by depositing uncured resilient material directly onto the mold surface and thereafter placing the contact subassemblies on top of the uncured resilient material that was deposited directly onto the mold surface such that the uncured resilient material that was deposited directly onto the mold surface prior to placement of the contact subassemblies is located between and in contact with both the contact subassemblies and the mold surface, the contact subassemblies including, prior to being placed into the mold, an electrically conductive contact having a flat portion defining lateral ends and side portions associated with the lateral ends of the flat portion and a lead wire secured to the electrically conductive contact;
• after the uncured resilient material, which was deposited directly onto the mold surface prior to placement of the contact subassemblies and is located between and in contact with both the contact subassemblies and the mold surface, has cured and secured the plurality of contact subassemblies to the mold surface, introducing additional resilient material into the mold to form an electrode array blank including a flexible body defining an exterior surface and the electrically conductive contacts below the exterior;
• and
• forming a plurality of windows in the electrode array blank that extend through the exterior surface of the flexible body to the electrically conductive contacts.