Electrical connection for a hermetic terminal for an active implantable medical device utilizing a ferrule pocket

A feedthrough that is attachable to the housing of an active implantable medical device (AIMD), the feedthrough comprising:

• a) an electrically conductive ferrule comprising:
• i) a ferrule sidewall defining a ferrule opening extending to a ferrule body fluid side end surface opposite a ferrule device side end surface;
• and
• ii) at least one recessed pocket residing in at least one of the ferrule body fluid side end surface and the ferrule device side end surface;
• and
• b) an oxide-resistant pocket-pad nested in the at least one recessed pocket and being electrically connected to the ferrule;
• c) an insulator hermetically sealed to the ferrule in the ferrule opening, the insulator extending to an insulator body fluid side end surface at or adjacent to the ferrule body fluid side end surface and an insulator device side end surface at or adjacent to the ferrule device side end surface, wherein, when the ferrule hermetically sealed to the insulator is attached to an opening in a housing of the AIMD, the ferrule and insulator body fluid side end surfaces and the ferrule and insulator device side end surfaces reside outside and inside the AIMD housing, respectively;
• d) at least one active via hole extending through the insulator to the insulator body fluid and device side end surfaces;
• and
• e) an active conductive pathway residing in and hermetically sealed to the insulator in the at least one active via hole.

A filtered feedthrough, comprising:

• a) a feedthrough, comprising:
• i) an electrically conductive ferrule, comprising:
• A) a ferrule sidewall defining a ferrule opening, the ferrule sidewall having a height extending to a ferrule device side end surface and a ferrule body fluid side end surface;
• and
• B) at least one recessed pocket having a depth extending from at least one of the ferrule device side and body fluid side end surfaces part-way through the height of the ferrule toward the other of the ferrule device side and body fluid side end surfaces;
• and
• ii) an oxide-resistant pocket-pad nested in the at least one recessed pocket in the ferrule, wherein the pocket-pad is electrically connected to the ferrule;
• iii) an insulator hermetically sealed to the ferrule in the ferrule opening, the insulator extending to an insulator device side end surface residing at or adjacent to the ferrule device side end surface and an insulator body fluid side end surface residing at or adjacent to the ferrule body fluid side end surface;
• iv) at least one via hole extending through the insulator to the insulator device side and body fluid side end surfaces;
• and
• v) a terminal pin disposed in and hermetically sealed to the insulator in the at least one via hole, wherein at least a device side portion of the terminal pin extends outwardly beyond the insulator device side end surface;
• and
• b) at least one filter capacitor disposed on or adjacent to the ferrule and insulator device side end surfaces, the filter capacitor comprising:
• i) a capacitor dielectric supporting at least one active electrode plate interleaved in a capacitive relationship with at least one ground electrode plate;
• ii) at least one active passageway extending through the capacitor dielectric, wherein a capacitor active metallization in the active passageway is electrically connected to the at least one active electrode plate, and wherein the terminal pin device side portion extends into the capacitor active passageway;
• and
• iii) a capacitor ground metallization attached to the capacitor dielectric and electrically connected to the at least one ground electrode plate;
• c) an active electrical connection electrically connecting the terminal pin device side portion residing in the active passageway to the capacitor active metallization electrically connected to the at least one active electrode plate;
• and
• d) a ground electrical connection electrically connecting the capacitor ground metallization to the pocket-pad electrically connected to the ferrule.