Implantable medical device with corrosion-resistant feedthrough assembly

A method of producing a feedthrough assembly, the method comprising:

• installing a solid insert within a central cavity of a housing, the central cavity extending through the housing and defined by an inner surface of the housing, wherein the housing has a stepped top side including a horizontal ridge surface and a raised lip that define a well, the horizontal ridge surface radially extending from the inner surface of the housing to the raised lip, the raised lip projecting from the horizontal ridge surface to a top surface of the raised lip at a top end of the housing, wherein a continuous angled inner surface of the raised lip extends to the top surface of the raised lip so a cross-sectional area of the well continuously increases along the continuous angled inner surface with increasing proximity to the top surface of the raised lip;
• installing one or more conductive elements through one or more apertures defined within the solid insert, the one or more conductive elements including one or more wires or one or more pins;
• depositing a metal filler within a joint defined by an outer surface of the solid insert and the inner surface of the housing that defines the central cavity;
• and
• forming a cover layer that covers a top surface of the solid insert and coats the metal filler, the cover layer composed of a non-corrosive sealant to inhibit corrosion of the metal filler, wherein forming the cover layer comprises at least partially filling the well with the non-corrosive sealant when in a flowable state so a perimeter of the non-corrosive sealant conforms to the angled inner surface.

An implantable medical device comprising:

• a header that comprises a header body, an antenna, and a sensing electrode, the antenna and the sensing electrode both disposed within the header body;
• and
• a feedthrough assembly mounted to a mounting end of the header body, the feedthrough assembly comprising:
• a housing including an inner surface that defines a central cavity through the housing, wherein the housing has a stepped top side including a horizontal ridge surface and a raised lip that define a well, the horizontal ridge surface radially extending from the inner surface of the housing to the raised lip, the raised lip projecting from the horizontal ridge surface to a top surface of the raised lip at a top end of the housing, wherein a continuous angled inner surface of the raised lip extends to the top surface of the raised lip so a cross-sectional area of the well continuously increases along the continuous angled inner surface with increasing proximity to the top surface of the raised lip;
• a solid insert disposed within the central cavity of the housing;
• conductive elements extending through apertures defined within the solid insert and extending through the central cavity of the housing, the conductive elements including one or more of wires or pins, wherein a first conductive element of the conductive elements is electrically connected to the antenna and a second conductive element of the conductive elements is electrically connected to the sensing electrode;
• a metal filler disposed within the apertures between the corresponding conductive elements and the solid insert to seal the apertures;
• and
• a non-corrosive sealant that fills the well and covers at least a portion of the top surface of the raised lip at the top end of the housing, the non-corrosive sealant forming a cover layer that covers a top surface of the solid insert and coats the metal filler to inhibit corrosion of the metal filler,
• wherein the header body couples to the housing of the feedthrough assembly and envelops the non-corrosive sealant.