Co-fired electrical feedthroughs for implantable medical devices having a shielded rf conductive path and impedance matching

Abstract

A co-fired electrical feedthrough for an implantable medical device (IMD) is provided having a shielded radio frequency (RF) conductive path. The feedthrough includes a monolithic structure derived from one or more layers of dielectric material and a conductive pathway extending through the monolithic structure for communicating RF signals into and from the IMD. An internal shield is formed to extend through at least one of the layers of dielectric material so as to surround the conductive pathway (e.g., in a coaxial relationship) and shield the RF conductive pathway from undesirable signals. This shielding of the RF conductive pathway prevents destructive EMI signals from entering into the IMD through the RF conductive pathway. In some embodiments, a monolithic structure containing embedded impedance matching elements is electrically connected to at least one conductive pathway in the feedthrough to perform impedance matching and/or filtering of the conductive pathway to other circuitry.