Hermetically sealed filtered feedthrough assembly having a capacitor with an oxide resistant electrical connection to an active implantable medical device housing

An active implantable medical device (AIMD), comprising:

• a) a device housing having an opening defined by an opening perimeter of the housing, wherein the device housing contains electronic circuits;
• b) a hermetic feedthrough, comprising:
• i) an insulator comprising an insulator perimeter surface extending to an insulator body fluid side opposite an insulator device side, wherein the insulator perimeter surface supports an insulator perimeter metallization;
• ii) at least one insulator active via hole extending to the insulator body fluid and device sides;
• iii) an adhered and agglomerated body of platinum particles hermetically sealing the at least one insulator active via hole, wherein closed pores reside between the platinum particles in the adhered and agglomerated body, and wherein the adhered and agglomerated body of platinum particles hermetically sealing the at least one insulator active via hole is selected from the group of substantially pure particles of platinum, and a mixture of platinum and alumina, and wherein the adhered and agglomerated body of platinum particles is substantially flush with the insulator device side and is characterized as having been sintered with the insulator to thereby hermetically seal the at least one insulator active via hole;
• iv) a gold braze hermetically sealing the insulator perimeter metallization to the opening perimeter of the device housing so that the insulator body fluid and device sides reside outside and inside the device housing, respectively;
• c) at least one capacitor disposed adjacent to the insulator device side, the capacitor comprising:
• i) at least one capacitor active electrode plate and at least one capacitor ground electrode plate disposed in a spaced and interleaved relationship within a capacitor dielectric body, wherein the capacitor ground electrode plate extends to an outer perimeter surface of the capacitor dielectric body;
• ii) a capacitor active passageway extending through the capacitor dielectric body;
• and
• iii) a capacitor active metallization disposed in the capacitor active passageway and being electrically connected to the at least one capacitor active electrode plate;
• and
• d) an insulator washer disposed between the insulator and the capacitor, wherein the insulator washer has at least one active hole aligned with the insulator active via hole and the capacitor active passageway;
• e) an active electrical connection disposed at least partially in the insulator washer active hole, wherein the active electrical connection electrically connects the capacitor active metallization in the capacitor active passageway electrically connected to the at least one capacitor active electrode plate to the adhered and agglomerated body of platinum particles in the insulator active via hole and to the electronic circuits contained in the device housing;
• and
• f) a ground electrical connection electrically connecting the capacitor ground metallization electrically connected to the at least one capacitor ground electrode plate at the outer perimeter surface of the capacitor dielectric body to the gold braze hermetically sealing the insulator perimeter metallization to the device housing.

A filtered feedthrough, comprising:

• a) a hermetic feedthrough, comprising:
• i) an insulator comprising an insulator perimeter surface extending to an insulator body fluid side opposite an insulator device side, wherein the insulator perimeter surface supports an insulator perimeter metallization;
• ii) at least one insulator active via hole extending to the insulator body fluid and device sides;
• and
• iii) an adhered and agglomerated body of platinum particles disposed in and hermetically sealing the at least one insulator active via hole, wherein closed pores reside between the platinum particles in the adhered and agglomerated body;
• b) at least one capacitor disposed adjacent to the insulator device side, the capacitor comprising:
• i) at least one capacitor active electrode plate and at least one capacitor ground electrode plate disposed in a spaced and interleaved relationship within a capacitor dielectric body, wherein the capacitor ground electrode plate extends to an outer perimeter surface of the capacitor dielectric body;
• ii) a capacitor active passageway extending through the capacitor dielectric body;
• and
• iii) a capacitor active metallization disposed in the capacitor active passageway and being electrically connected to the at least one capacitor active electrode plate;
• and
• c) an active electrical connection electrically connecting the capacitor active metallization in the capacitor active passageway electrically connected to the at least one capacitor active electrode plate to the adhered and agglomerated body of platinum particles in the insulator active via hole.