Speaker
Description
Hearing aids and cochlear implants restore auditory perception for many patients but remain limited by environmental susceptibility and restricted daily use. Completely implantable auditory prostheses promise continuous, unobtrusive operation. However, their widespread adoption is constrained by the lack of implantable acoustic sensors that are simultaneously low-noise, mechanically robust, and suitable for long-term implantation. We have designed and fabricated ultra-miniature piezoelectric microelectromechanical systems (MEMS) accelerometers for middle-ear sound sensing. Methods for meeting process flow and manufacturing challenges to build the muti-band devices for speech-relevant noise performance over the 0.1–8 kHz bandwidth are presented. Building on this validated MEMS sensor design, we also address implantable packaging as the next-in-queue critical challenge. Titanium-based package architectures are developed using precision titanium stamping and additive manufacturing, integrated with alumina ceramic substrates and metallized electrical feedthroughs. The resulting packages aim to meet the unique challenges of sub-millimeter form factors and sub-20 milligram total mass while maintaining mechanical robustness and hermetic encapsulation. Ongoing and planned evaluations consider seal integrity, material biocompatibility, and the influence on sensing performance in a temporal bone configuration, guided by established standards for implantable medical devices.