Patent Description:
Implantable medical devices such as an implantable pacemaker can deliver pacing pulses to a patient's heart and monitor conditions of the patient's heart. In some examples, the implantable pacemaker includes a pulse generator and one or more electrical leads. The pulse generator may, for example, be implanted in a small pocket in the patient's chest. The electrical leads can be coupled to the pulse generator, which may contain circuitry that generates pacing pulses and/or senses cardiac electrical activity. The electrical leads may extend from the pulse generator to a target site (e.g., an atrium and/or a ventricle) such that electrodes at the distal ends of the electrical leads are positioned at the target site. The pulse generator may provide electrical stimulation to the target site and/or monitor cardiac electrical activity at the target site via the electrodes.

Other implantable pacemakers are configured to be implanted entirely within a chamber of the heart. Such pacemakers can be referred to as intracardiac pacing devices or leadless pacing devices and can include one or more electrodes on their outer housings to deliver therapeutic electrical signals and/or sense intrinsic depolarizations of the heart. Such pacemakers can be positioned within or outside of the heart and, in some examples, can be anchored to a wall of the heart via a fixation mechanism.

<CIT> relates to a leadless device with overmolded components.

<CIT> relates to a biostimulator having a flexible circuit assembly.

The techniques of this disclosure generally relate to a feedthrough header assembly and an electronics module that utilizes such feedthrough header assembly. The electronics module can include a feedthrough header assembly and an electronic layer. The assembly can include a conductive header that includes a conductive inner surface and a contact disposed on the inner surface and electrically connected to the header. The assembly can also include a feedthrough pin that is electrically isolated from the header. The electronic layer can include a substrate and an electronic component disposed on or within the substrate, were the electronic component is electrically connected to the contact of the conductive header. A major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header. The feedthrough pin extends through the dielectric substrate and the header and beyond an outer surface of the header while maintaining isolation from the header.

In one example, aspects of this disclosure relate to an electronics module that includes a feedthrough header assembly. The assembly includes a conductive header having a conductive inner surface, an outer surface, and a contact disposed on the inner surface and electrically connected to the header; and a feedthrough pin disposed within a via that extends through the header between the inner surface and the outer surface of the header. The feedthrough pin is electrically isolated from the header and includes a first end adjacent to the inner surface of the header and a second end adjacent to the outer surface of the header. The electronics module further includes an electronic layer having a substrate and an electronic component disposed on or within the substrate. The electronic component is electrically connected to the contact of the conductive header such that the electronic component is electrically connected to the header. A major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header.

In another example, aspects of this disclosure relate to an implantable medical device that includes a power source and an electronics module electrically connected to the power source. The electronics module includes an electronic layer and a feedthrough header assembly electrically connected to the electronic layer. The electronic layer includes a substrate and an electronic component disposed on the substrate. Further, the feedthrough header assembly includes a conductive header having a conductive inner surface, an outer surface, and a contact disposed on the inner surface and electrically connected to the header; and a feedthrough pin disposed within a via that extends through the header between the inner surface and the outer surface of the header. The feedthrough pin is electrically isolated from the header and includes a first end adjacent to the inner surface of the header and a second end adjacent to the outer surface of the header. The electronic component is connected to the contact of the conductive header such that the electronic component is electrically connected to the header. Further, a major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header.

In another example, aspects of this disclosure relate to a method that includes disposing a feedthrough pin through a via of a conductive header, where a first end of the feedthrough pin is adjacent to a conductive inner surface of the header and a second end of the feedthrough pin is adjacent to an outer surface of the header. The method further includes disposing a contact on the inner surface of the header such that it is electrically connected to the header; and electrically connecting an electronic component of an electronic layer to the contact such that the electronic component is electrically connected to the header. The electronic component is disposed on or within a substrate of the electronic component. Further, a major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header.

The techniques of this disclosure generally relate to a feedthrough header assembly and an electronics module that utilizes such feedthrough header assembly. The electronics module can include a feedthrough header assembly and an electronic layer. The assembly can include a conductive header that includes a conductive inner surface and a contact disposed on the inner surface and electrically connected to the header. The assembly can also include a feedthrough pin that is electrically isolated from the header. The electronic layer can include a substrate and an electronic component disposed on or within the substrate, were the electronic component is electrically connected to the contact of the conductive header. A major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header. The feedthrough pin extends through the header and beyond an outer surface of the header while maintaining isolation from the header.

Typical header assemblies of implantable medical devices can include a feedthrough pin that is electrically connected to an electronics module disposed within a housing of the device. The feedthrough pin can extend from inside the housing and beyond a header that is connected to the housing. Because one or both of the housing or the header can be electrically active, the feedthrough pin is typically electrically isolated from both the header and the housing. An opening in the header and the housing through which the feedthrough pin extends must be sealed such that body fluids and contaminants do not flow into an interior of the housing where they can damage electronic components.

One or more embodiments of the present disclosure can provide a feedthrough header assembly that includes a feedthrough pin that can be connected to an electronics module disposed within a housing of a device, where the feedthrough pin is electrically connected to the module in a reliable manner while efficiently utilizing space within the housing. The feedthrough header assembly can be a solderable component or subassembly that is compatible with various standard surface mount processing and connects to an integrated circuit or die stack in a reliable and volumetrically efficient manner.

<FIG> is a schematic view of one embodiment of an implantable medical device <NUM> (IMD) disposed within a body of a patient <NUM>. The IMD <NUM> can include any suitable medical device, e.g., a pacing device, pressure sensing device, cardiac monitor, other physiologic sensor, etc. The IMD <NUM> can include an arrangement of an electronics module and a feedthrough header assembly as is further described herein. IMD <NUM> can be, for example, an implantable leadless pacing device that is configured for implantation entirely within one of the chambers of a heart <NUM> and that provides electrical signals to the heart beneath a sternum <NUM> via electrodes carried on the housing of the pacing device.

IMD <NUM> is generally described as being attached within a chamber of the heart <NUM> as an intracardiac pacing device. In one or more embodiments, IMD <NUM> can be attached to an external surface of the heart <NUM> such that the device is disposed outside of the heart but can pace a desired chamber. In one or more embodiments, IMD <NUM> is attached to an external surface of the heart <NUM>, and one or more components of the device can be in contact with an epicardium of the heart. The IMD <NUM> is schematically shown in <FIG> attached to a wall of a ventricle of the heart <NUM> via one or more fixation elements (e.g., tines, helix, etc.) that penetrate the tissue. These fixation elements can secure the IMD <NUM> to the cardiac tissue and retain an electrode (e.g., a cathode or an anode) in contact with the cardiac tissue. IMD <NUM> can be implanted at or proximate to the apex of the heart. In one or more embodiments, a pacing device may be implanted at other ventricular locations, e.g., on the free-wall or septum, an atrial location, or any location on or within the heart <NUM>.

<FIG> is a schematic side view of the IMD <NUM> of <FIG>. In one or more embodiments, the IMD <NUM> is adapted to be implanted within a chamber of the heart <NUM> of the patient <NUM>, e.g., to monitor electrical activity of the heart and/or provide electrical therapy to the heart. In the example shown in <FIG>, the IMD <NUM> includes a housing <NUM>, fixation tines <NUM>, and electrodes <NUM> and <NUM>.

The housing <NUM> of the IMD <NUM> can include any suitable dimensions and take any suitable shape or shapes. The housing <NUM> extends between a first end <NUM> and a second end <NUM> along a longitudinal axis <NUM>. In one or more embodiments, the housing <NUM> can have a cylindrical (e.g., pill-shaped) form factor. In one or more embodiments, the housing <NUM> includes an elongated tubular housing. Further, the housing <NUM> can include any suitable material or materials as is further described herein.

The IMD <NUM> can include a fixation mechanism adapted to fix pacing device <NUM> to tissue within the body of the patient <NUM>. For example, in the embodiment illustrated in <FIG>, the IMD <NUM> includes fixation tines <NUM> extending from the housing <NUM> that are adapted to engage with tissue to substantially fix a position of the housing within the patient <NUM>. In one or more embodiments, the fixation tines <NUM> are adapted to anchor housing <NUM> to the cardiac tissue such that pacing device <NUM> moves along with the cardiac tissue during cardiac contractions. Fixation tines <NUM> can include any suitable material or materials, e.g., a shape memory material (e.g., Nitinol). Although the IMD <NUM> includes a plurality of fixation tines <NUM> that are adapted to anchor the device to tissue, in one or more embodiments, the device can be fixed to tissue using other types of fixation mechanisms, such as, but not limited to, barbs, coils, and the like.

Housing <NUM>, also referred to as an elongated housing, houses electronic components of the IMD <NUM>, e.g., sensing circuitry for sensing electrical activity via electrodes <NUM> and <NUM> and therapy generation circuitry for delivering electrical stimulation therapy via the electrodes. Electronic components can include any discrete and/or integrated electronic circuit components that implement analog and/or digital circuits capable of producing the functions attributed to the IMD <NUM> described herein. In one or more embodiments, housing <NUM> can also house components for sensing other physiological parameters, such as acceleration, pressure, sound, and/or impedance. Although shown with two electrodes <NUM> and <NUM>, the device <NUM> can include any suitable number of electrodes disposed in any suitable portion or portions of the housing.

Additionally, the housing <NUM> can also house a memory that includes instructions that, when executed by processing circuitry housed within housing, cause the IMD <NUM> to perform various functions attributed to the device herein. In one or more embodiments, the housing <NUM> can house communication circuitry that enables the IMD <NUM> to communicate with other electronic devices, such as a medical device programmer. In one or more embodiments, the housing <NUM> can house an antenna for wireless communication. The housing <NUM> can also house a power source, such as a battery.

The housing <NUM> can be hermetically or near-hermetically sealed using any suitable technique or techniques to help prevent fluid ingress into housing. For example, in one or more embodiments, one or more portions of the housing <NUM> can be hermetically sealed together utilizing one or more laser diffusion bonding techniques described in co-owned <CIT>, entitled KINETICALLY LIMITED NANOSCALE DIFFUSION BOND STRUCTURES AND METHODS.

The IMD <NUM> include the electrodes <NUM>, <NUM> that can be connected to the housing utilizing any suitable technique or techniques. In one or more embodiment, at least one of the electrodes <NUM>, <NUM> can be mechanically connected to housing <NUM>. In one or more embodiments, at least one of the electrodes <NUM>, <NUM> can be defined by an outer portion of the housing <NUM> that is electrically conductive. For example, electrode <NUM> can be defined by a tissue-exposed conductive portion of housing <NUM>.

Electrodes <NUM>, <NUM> are electrically isolated from each other. Electrode <NUM> can be referred to as a tip electrode, and fixation tines <NUM> can be adapted to anchor the IMD <NUM> to tissue such that electrode <NUM> maintains contact with the tissue. In one or more embodiments, fixation tines <NUM> can also be electrically connected to one or more electronic components such that the tines are adapted to direct an electrical signal to tissue of the patient and/or receive an electronic signal from the tissue. In one or more embodiments, a portion of housing <NUM> can be covered by, or formed from, an insulative material to isolate electrodes <NUM> and <NUM> from each other and/or to provide a desired size and shape for one or both of electrodes.

Electrode <NUM> can be a portion of housing <NUM>, e.g., second portion <NUM>, that does not include such insulative material. Electrode <NUM> can be most or all of housing <NUM>, but most of the housing (other than electrode <NUM>) can be covered with an insulative coating. In one or more embodiments, electrode <NUM> may be coated with materials to promote conduction. In one or more embodiments, electrode <NUM> can be part of a separate ring portion of housing <NUM> that is conductive. Electrodes <NUM>, <NUM>, which may include conductive portion(s) of the first portion <NUM> of housing <NUM>, can be electrically connected to at least some electronics of pacing device <NUM> (e.g., sensing circuitry, electrical stimulation circuitry, or both). In one or more embodiments, the housing <NUM> can include an end cap <NUM> that can house or enclose a feedthrough header assembly (e.g., feedthrough header assembly <NUM> of <FIG>) to electrically connect the electrode <NUM> to the electronics within the housing <NUM> while electrically isolating the electrode from the housing <NUM>, e.g., including electrode <NUM> or other conductive portions of the housing.

In the embodiment illustrated in <FIG>, the housing <NUM> includes the first portion <NUM> and the second portion <NUM>. The first portion <NUM> can be disposed adjacent to the first end <NUM> of the housing <NUM>, and the second portion <NUM> can be disposed adjacent to the second end <NUM> of the housing. As used herein, the term "adjacent to the first end" means that an element or component is disposed closer to the first end <NUM> of the housing <NUM> than to the second end <NUM> of the housing. Further, the term "adjacent to the second end" means that an element or component is disposed closer to the second end <NUM> of the housing <NUM> than to the first end <NUM> of the housing. The second portion <NUM> can, in one or more embodiments, define at least part of a power source case that houses a power source (e.g., a battery) of the IMD <NUM>. In one or more embodiments, the second portion <NUM> can include the conductive portion of the housing <NUM> that forms the electrode <NUM>.

The first portion <NUM> of the housing <NUM> can be connected to the second portion <NUM> of the housing using any suitable technique or techniques. In one or more embodiments, the first portion <NUM> of the housing <NUM> can be connected to the second portion <NUM> of the housing using laser bonding. For example, electromagnetic radiation (e.g., light) can be directed through an outer surface of the first portion <NUM> and focused at an interface between the first portion and the second portion <NUM> to form a laser bond.

Any suitable electromagnetic radiation can be utilized to form a bond between the first portion <NUM> and the second portion <NUM> of the housing <NUM>. In one or more embodiments, the electromagnetic radiation can include laser light that can include any suitable wavelength or range of wavelengths. In one or more embodiments, the laser light can include light having a wavelength of at least <NUM>. In one or more embodiments, the laser light can include a wavelength of no greater than <NUM>,<NUM>. For example, laser light can include UV light, visible light, IR light, and combinations thereof. In one or more embodiments, a UV laser can be utilized to provide light having a wavelength of about <NUM> and a pulse width of about <NUM> ns. In one or more embodiments, the materials for the first and second portions <NUM>, <NUM> of the housing <NUM>, and the power level and wavelength of the light used may be selected such that the light may not directly damage, ablate, warp, or cut the housing, and such that the first and second portions of the housing retain their bulk properties.

In general, light can be provided by any suitable laser or laser system. For example, the laser may generate light having a relatively narrow set of wavelengths (e.g., a single wavelength). The light emitted by the laser may form a collimated beam that may not be focused at a particular point. The light emitted by the laser may be focused at interfaces between the first portion <NUM> and the second portion <NUM> of the housing <NUM> to generate a laser bond.

Although the laser may provide light that has a narrow range of wavelengths, in one or more embodiments, the laser may represent one or more devices that emit light having a wider range of wavelengths than a single typical laser. A wide variety of devices may be used to emit light having a narrow or wide range of wavelengths. In one or more embodiments, the laser may include one or more laser devices including diode and fiber lasers. Laser sources may also include, e.g., TI sapphire, argon ion, Nd:YAG, XeF, HeNe, Dye, GaAs/AlGaAs, CO<NUM>, Alexandrite, InGaAs, InGaAsP, Nd:glass, Yb:YAG, or Yb fiber lasers. The laser device may also include one of continuous wave, modulated, or pulsed modes. Accordingly, a wide variety of laser devices may be used in the bonding process. In one or more embodiments, a power level of the laser may be set to approximately <NUM> W, distributed across the approximate focused beam diameter of <NUM>, with a top hat or Gaussian spatial energy profile.

In the embodiment of <FIG>, the IMD <NUM> can also include a flange <NUM> connected to the second portion <NUM> of the housing <NUM> at the second end <NUM> of the housing that defines an opening. The flange <NUM> can enable medical instruments to attach to the IMD <NUM>, e.g., for delivery and/or extraction of the device. For example, a tether that extends through a catheter inserted into the heart <NUM> (<FIG>) can be attached to the flange <NUM> and/or threaded through the opening to implant or extract the IMD <NUM>.

<FIG> is a schematic block diagram of one embodiment of the IMD <NUM> including a power source <NUM> (e.g., battery), an electronics module <NUM>, and an electrical contact assembly <NUM>. Although the IMD of <FIG> is described as IMD <NUM>, the structures shown in <FIG> can also be used in other implantable or external medical devices, such as cardioverter-defibrillators, physiological monitors, or neurostimulators, or any other electronic devices.

The housing <NUM> includes the first and second portions <NUM>, <NUM> and a side wall <NUM> disposed within the housing between the battery <NUM> and the electrical contact assembly <NUM>. The side wall <NUM> can be disposed within the first and second housing portions <NUM>, <NUM> or at the boundary of first and second housing portions. In one or more embodiments, the first and second housing portions <NUM>, <NUM> are common with a ground terminal of battery <NUM>. In one or more embodiments, one or both of the first and second housing portions <NUM>, <NUM> is non-conductive. For example, first housing portion <NUM> can be formed of a non-conductive material, such as sapphire, which may allow easier transmission of electromagnetic signals into and out of the housing <NUM> than a metal or other conductive material would allow.

As shown in the embodiment illustrated in <FIG>, the side wall <NUM> extends across housing <NUM> between the battery <NUM> on one side and electrical contact assembly <NUM> on the other side. The side wall <NUM> can include at least one feedthrough (not shown) to allow for electrical connection between the battery <NUM> and the electronics module <NUM>. As discussed herein, feedthrough header assembly <NUM> can also include at least one feedthrough to allow for an electrical connection between electrode <NUM> and electronic layers <NUM>. Electronics module <NUM> is disposed between the electrode <NUM> and electrical contact assembly <NUM>. In one or more embodiments, electrical contact assembly <NUM> can be fixed to side wall <NUM> to provide mechanical support for the electronics module <NUM>. The electronic contact assembly <NUM> provides an electrical connection between the battery <NUM> and the electronics module <NUM>.

The IMD <NUM> can also include a battery header <NUM> disposed between the battery <NUM> and the electrical contact assembly <NUM>. The side wall <NUM> can form part or all of the battery header <NUM>. The battery header <NUM>, the side wall <NUM>, and the electrical contact assembly <NUM> can be electrically connected to the electronics module <NUM> using any suitable technique or techniques. In one or more embodiments, the battery header <NUM>, the side wall <NUM>, and/or electrical contact assembly <NUM> can include feedthroughs and/or openings for creating an electrical connection between the battery <NUM> and electronics module <NUM>.

The electrical contact assembly <NUM> can include any suitable assembly for electrically connecting the electronics module <NUM> and the battery <NUM>, e.g., one or more embodiments of electrical contact assemblies described in co-owned <CIT>, entitled ELECTRONICS ASSEMBLY FOR IMPLANTABLE MEDICAL DEVICE. In one or more embodiments, the electrical contact assembly <NUM> can include a spring contact for holding electronics module <NUM> in place and for providing electrical connections between the electronics module and the battery <NUM>.

The IMD <NUM> can be manufactured utilizing a single tube for the first housing portion <NUM> or as two tube sections for such housing portion. Using a single tube for the housing portion <NUM>, in contrast to two sections, e.g., two half-pipes, may lower the cost and complexity of the encasement for pacing device <NUM>. A single tube opens up new encasement options and can be manufactured from alternate materials. For example, a single sapphire tube utilized for the first housing portion <NUM> can allow for wireless charging of the battery <NUM> even when the IMD <NUM> is implanted within a patient.

In one or more embodiments, at least one of the first and second portions <NUM>, <NUM> of the housing <NUM> can include a substantially transparent material. As used herein, the phrase "substantially transparent" means that the portion <NUM>, <NUM> of the housing <NUM> transmits greater than <NUM>% of electromagnetic radiation incident on the portion for a selected wavelength or range of wavelengths, assuming no reflection at the air-substrate boundaries. In one or more embodiments, at least one of the first and second portions <NUM>, <NUM> can be substantially transmissive to electromagnetic radiation having a wavelength of at least <NUM>. In one or more embodiments, at least one of the first and second portions <NUM>, <NUM> can be substantially transmissive to electromagnetic radiation having a wavelength of greater than <NUM>,<NUM>. In one or more embodiments, at least one of the first and second portions <NUM>, <NUM> can be substantially transmissive to electromagnetic radiation having a wavelength in a range of <NUM> to <NUM>,<NUM>. In one or more embodiments, at least one of the first and second portions <NUM>, <NUM> can be substantially transmissive to at least one of UV light, visible light, or IR light. The substantially transparent material can include at least one of glass, quartz, silica, sapphire, silicon carbide, diamond, or gallium nitride.

In one or more embodiments, the first housing portion <NUM> can include a substantially transparent material such that one or more sensors, emitters, or detectors can be disposed within the first housing portion and transmit or receive electromagnetic radiation through such portion. For example, <FIG> is a perspective view of the IMD <NUM> of <FIG> with a transparent first portion <NUM> partially removed for clarity. As shown in <FIG>, the electronics module <NUM> is disposed within the first portion <NUM>.

The electronics module <NUM> can include any suitable elements or components. For example, as shown in <FIG>, the electronics module <NUM> includes one or more electronic layers <NUM> and a feedthrough header assembly <NUM> electrically connected to the one or more electronic layers <NUM>. The electronics module <NUM> can also include one or more coils <NUM> electrically connected to the electronic layers <NUM>.

<FIG> are various schematic views of the electronics module <NUM> of the pacing device <NUM> of <FIG>. The module <NUM> includes electronic layers <NUM> and the feedthrough header assembly <NUM> electrically connected to the electronic layers.

The electronic layers <NUM> include a first electronic layer <NUM>, a second electronic layer <NUM>, and a third electronic layer <NUM>. Although illustrated as including three electronic layers, the electronic layers <NUM> can include any suitable number of layers, e.g., one, two, three, four, five, or more layers. Each layer of the electronic layers <NUM> can include a substrate. For example, first electronic layer <NUM> includes a substrate <NUM> having a first major surface <NUM> and a second major surface <NUM>.

The electronic layers <NUM> can be disposed in any suitable relationship relative to the feedthrough header assembly <NUM> and the battery <NUM>. In one or more embodiments, the electronic layers <NUM> can be disposed such that they are substantially orthogonal to the longitudinal axis <NUM> (<FIG>) of the IMD <NUM>, where the housing <NUM> of the device extends along the longitudinal axis. For example, the first major surface <NUM> of the substrate <NUM> of the first electronic layer <NUM> is substantially orthogonal to the longitudinal axis <NUM> of the housing <NUM>. As used herein, the term "substantially orthogonal" means that the longitudinal axis <NUM> forms an angle with a substrate of one or more of the electronic layers <NUM> of no greater than <NUM> degrees.

The electronic layers <NUM> can be electrically connected together using any suitable technique or techniques. In or more embodiments, one or more of the electronic layers <NUM> can include one or more conductive vias that are disposed through the respective substrate of one or more of the electronic layers. Further, one or more conductive pads <NUM> can be disposed on one or more of the electronic layers <NUM> to provide electrical connections between the feedthrough header assembly <NUM> and the electronic layers, between one or more of the electronic layers, and between the electronic layers and the electrical contact assembly <NUM>. For example, conductive pad <NUM> is disposed between (e.g., between conductive surfaces of) the feedthrough header assembly <NUM> and the first electronic layer <NUM> to provide an electrical connection between the feedthrough header assembly and the first electronic layer. In one or more embodiments, this connection can be between the housing <NUM> and the first electronic layer <NUM> or between one or more of the feedthrough pin <NUM> of the assembly and the first electronic layer. The conductive pads <NUM> can include any suitable conductive contact, e.g., solder bumps, solder balls, conductive epoxy, braze alloys, etc..

One or more of the electronic layers <NUM> can include an electronic component disposed on its respective substrate. For example, first electronic layer <NUM> includes electronic component <NUM> disposed on the first major surface <NUM> of the substrate <NUM>. The electronic component <NUM> can be disposed on at least one of the first major surface <NUM> or second major surface <NUM> of the substrate <NUM>. Any suitable number of electronic components can be disposed on one or both major surfaces <NUM>, <NUM> of the substrate <NUM>. Further, the electronic component <NUM> can be electrically connected to one or more additional electronic components disposed on the substrate <NUM> or on the second or third electronic layers <NUM>, <NUM> using any suitable technique or techniques. In one or more embodiments, the electronic component <NUM> can be disposed on a patterned conductive layer (not shown) disposed on the substrate <NUM> using any suitable technique or techniques. One or more conductive vias can be disposed between the first and second major surfaces <NUM>, <NUM> of the substrate <NUM> to provide one or more conductive pathways between the patterned conductive layer and other elements or components disposed on an opposite side of the substrate <NUM> from the electronic component <NUM>. Further, one or more conductive pads <NUM> can be directly connected to the electronic component <NUM> to electrically connect the component to one or more additional components or devices.

Electrically connected to one or more of the electronic layers <NUM> is the coil <NUM>. Such coil <NUM> can include any suitable number of coils disposed on or within a housing <NUM> and one or more electronic components also disposed within the housing. The coil <NUM> can be utilized to inductively couple the IMD <NUM> with an external inductive charging system for charging the device when it is implanted within the body of the patient <NUM> or for telemetry or other types of communication with a transceiver that is external to the patient's body. The coil <NUM> can be electrically connected to the electronic layers <NUM> using any suitable technique or techniques. Further, the coil <NUM> can be electrically connected, e.g., to third electronic layer <NUM> using any suitable technique or techniques. The housing <NUM> of the coil <NUM> can provide one or more electrical pathways between the battery <NUM> and the electronic layers <NUM> using any suitable technique or techniques. In one or more embodiments, one or more conductors <NUM> (<FIG>) can be disposed on or within the housing <NUM> to provide one or more of these electrical pathways.

Also electrically connected to one or more of the electronic layers <NUM> is the feedthrough header assembly <NUM>. As shown in <FIG>, the assembly <NUM> includes a conductive header <NUM> that has an inner surface <NUM>, an outer surface <NUM>, and one or more contacts <NUM> disposed on the inner surface and electrically connected to the header. The assembly <NUM> further includes a feedthrough pin <NUM> disposed within a via <NUM> (<FIG>) that extends through the header <NUM> between the inner surface <NUM> and the outer surface <NUM> of the header. The feedthrough pin <NUM> is electrically isolated from the header <NUM> and includes a first end <NUM> adjacent to the inner surface <NUM> of the header and a second end <NUM> adjacent to the outer surface <NUM> of the header. As used herein, the term "adjacent to the inner surface" means that an element or component is disposed closer to the inner surface <NUM> of the header <NUM> than to the outer surface <NUM> of the header. Further, as is also used herein, the term "adjacent to the outer surface" means that an element or component is disposed closer to the outer surface <NUM> of the header <NUM> than to the inner surface <NUM>.

The assembly <NUM> can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the assembly <NUM> can include an elliptical cross-section in a plane substantially parallel to the inner surface <NUM> of the header <NUM>.

The header <NUM> can also take any suitable shape or shape and have any suitable dimensions. Further, the header <NUM> can include any suitable material or materials, e.g., at least one of titanium, copper, niobium, tantalum, or alloys thereof. In one or more embodiments, the header <NUM> is electrically conductive.

The header <NUM> can include a flange <NUM> that at least in part forms the outer surface <NUM> of the header. The flange <NUM> can be adapted to connect the header <NUM> to the end cap <NUM> (<FIG>).

The feedthrough header assembly <NUM> can further include one or more conductive contacts <NUM> disposed on the inner surface <NUM> of the header <NUM> and electrically connected to the header. Any suitable number of contacts <NUM> can be disposed on the inner surface <NUM> in any suitable arrangement or array. The contacts <NUM> can include any suitable conductive structure, e.g., at least one of a solder bump, solder paste, conductive epoxy, or conductive joint.

For example, <FIG> is a schematic cross-section view of one embodiment of a contact <NUM>. The contact <NUM> can include a seed or adhesion layer <NUM> disposed on an inner surface of a conductive header (e.g., inner surface <NUM> of conductive header <NUM> of <FIG>), a conductive layer <NUM> disposed on the seed layer, and a solder ball <NUM> disposed on the conductive layer such that the conductive layer and the seed layer are between the solder ball and the conductive inner surface of the header. The seed layer <NUM> and the conductive layer <NUM> can include any suitable conductive material or materials, e.g., a material that improves adhesion of subsequent metal layers such as nickel, nickel-vanadium, titanium, zirconium, etc. The conductive layer <NUM> can be additional metallization to provide enhanced conduction and solderability such as copper, gold, tin-lead, or other solderable conductive materials. The seed layer <NUM> and conductive layer <NUM> can include the same materials or different materials. Further, the seed layer <NUM> and the conductive layer <NUM> can be disposed using any suitable technique or techniques, e.g., plating, sputtering, sintering, vapor deposition, etc. In one or more embodiments, the seed layer <NUM> can be disposed on the inner surface of the header followed by deposition of the conductive layer <NUM> on the seed layer. The seed and conductive layers <NUM>, <NUM> can be patterned using any suitable technique or techniques to form contacts. The solder ball <NUM> can also include any suitable conductive material or materials, e.g., the same materials described herein regarding contacts <NUM>, can be disposed on the conductive layer using any suitable technique or techniques, e.g., physical masking of non-target areas during vapor deposition or plating, laser defined patterns by removal of undesired material after full deposition, etc..

Returning to <FIG>, the contacts <NUM> can be disposed on the inner surface <NUM> of the header <NUM> using any suitable technique or techniques, e.g., sputtering, plating, etc. For example, a conductive material can be disposed on the inner surface <NUM> and then patterned to form the contacts <NUM>. In one or more embodiments, the contacts <NUM> can be integral with the header <NUM>, i.e., the contacts and the header are formed as a single entity.

The contacts <NUM> can be adapted to electrically connect the header <NUM> to one or more of the electronic layers <NUM> of the electronics module <NUM>. In one or more embodiments, the contacts <NUM> can provide redundant connections between the header <NUM> and other components of the IMD <NUM>, e.g., one or more of the electronic layers <NUM>. The electronic components <NUM> of the electronic layers <NUM> can be electrically connected to the one or more contacts <NUM> of the conductive header <NUM> such that the electronic components are electrically connected to the header <NUM>. In one or more embodiments, the major surface of the substrate of an electronic layer of the layers <NUM> faces the conductive inner surface <NUM> of the header <NUM> without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface <NUM> of the header <NUM>. For example, as shown in <FIG>, the second major surface <NUM> of the substrate <NUM> of the first electronic layer <NUM> faces the conductive inner surface <NUM> of the header <NUM> without any intervening nonconductive layers disposed between the second major surface of the substrate and the conductive inner surface of the header. Conductive pads <NUM> of the first electronic layer <NUM> that are disposed on the second major surface <NUM> of the substrate <NUM> are spaced apart from the conductive inner surface <NUM> of the header <NUM> and isolated from the header by a gap that is formed between the electronic layers <NUM> and the header. No nonconductive layers are, therefore, required between the electronic layers <NUM> and the header <NUM> to isolate the electronic layers from the header.

Disposed through the header <NUM> between the inner surface <NUM> and the outer surface <NUM> is the via <NUM>. The via <NUM> can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the via <NUM> can have a cross-sectional area in a plane parallel to the inner surface <NUM> of the header <NUM> that is greater than a cross-sectional area of the feedthrough pin <NUM> in the same plane.

The feedthrough pin <NUM> is disposed within the via <NUM> of the header <NUM> and includes the first end <NUM> that is adjacent to the inner surface <NUM> of the header <NUM> and the second end <NUM> that is adjacent to the outer surface <NUM> of the header. The feedthrough pin <NUM> can include any suitable material or materials, e.g., the same materials described herein regarding the header <NUM>. Further, the feedthrough pin <NUM> can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the first end <NUM> of the feedthrough pin <NUM> can extend beyond the inner surface <NUM> of the header <NUM> any suitable length. In one or more embodiments, the first end <NUM> of the feedthrough pin <NUM> can be flush with the inner surface <NUM> of the header <NUM> such that an end surface at the first end of the feedthrough pin <NUM> is in a plane defined by the inner surface <NUM> of the header <NUM>, or the first end can be recessed from the inner surface such that the first end is disposed within the via <NUM>.

As mentioned herein, the feedthrough pin <NUM> can be electrically isolated from the header <NUM> using any suitable technique or techniques. For example, insulating material <NUM> can be disposed within the via <NUM>. As shown in <FIG>, insulating material <NUM> can be disposed within the via <NUM> between a wall portion <NUM> of the via and the feedthrough pin <NUM> and at least a portion <NUM> of the via <NUM> such that the feedthrough pin is electrically isolated from the header. Any suitable insulating material <NUM> can be utilized to isolate the feedthrough pin <NUM> within the via <NUM>, e.g., glass, sapphire, epoxy, or other non-conductive material that provides a seal, etc..

The feedthrough pin <NUM> can be adapted to be electrically connected to one or more of the electronic layers <NUM> of the electronics module <NUM>. In one or more embodiments, the feedthrough pin <NUM> can include a contact <NUM> disposed at the first end <NUM> of the pin. The contact <NUM> can include any suitable contact or contacts, e.g., contact <NUM>. The contact <NUM> can be disposed at the first end <NUM> of the pin <NUM> using any suitable technique or techniques. In one or more embodiments, the contact <NUM> is integral with the first end <NUM> of the pin <NUM> and can take any suitable shape or shapes, e.g., the pin and contact can form a nail head at the first end of the pin. Further, in one or more embodiments, a conductive pad or pads can be electrically connected to the feedthrough pin <NUM> to provide an electrical connection between the feedthrough pin and one or more of the electronic layers <NUM>.

For example, <FIG> are schematic perspective and cross-section views of another embodiment of a feedthrough header assembly <NUM>. All of the design considerations and possibilities described herein regarding feedthrough header assembly <NUM> of <FIG> apply equally to feedthrough header assembly <NUM> of <FIG>. The assembly <NUM> includes a header <NUM> that has a conductive inner surface <NUM>, an outer surface <NUM>, and one or more contacts <NUM> disposed on the inner surface and electrically connected to the header. The assembly further includes a feedthrough pin <NUM> disposed within a via <NUM> that extends through the header to <NUM> between the inner surface <NUM> and the outer surface <NUM> of the header. The feedthrough pin <NUM> is electrically isolated from the header <NUM> and includes a first end <NUM> adjacent to the inner surface <NUM> of the header <NUM> and a second end <NUM> adjacent to the outer surface <NUM> of the header.

One difference between the feedthrough header assembly <NUM> of <FIG> and the assembly <NUM> of <FIG> is that the assembly <NUM> includes a conductive pad <NUM> disposed at the first end <NUM> of the feedthrough pin <NUM>. The conductive pad <NUM> is electrically connected to the feedthrough pin <NUM> using any suitable technique or techniques, e.g., the conductive pad can be welded to the feedthrough pin. In one or more embodiments, the conductive pad <NUM> is integral with the feedthrough pin <NUM>. The conductive pad <NUM> can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, one or more contacts <NUM> can be disposed on the conductive pad <NUM> that are electrically connected to the conductive pad using any suitable technique or techniques. The conductive pad <NUM> can electrically connect the feedthrough pin <NUM> and one or more electronic layers of an electronic module (e.g., electronic layers <NUM> of electronic module <NUM> of <FIG>). Further, the conductive pad can include any suitable conductive material or materials, e.g., at least one of copper, niobium, titanium, platinum, or platinum-iridium.

In one or more embodiments, the conductive pad <NUM> can be disposed within a recessed surface <NUM> disposed in the inner surface <NUM> of the header <NUM>. The recessed surface <NUM> can take any suitable shape or shapes and have any suitable dimensions. In one or more embodiments, the recessed surface <NUM> can have a depth that is substantially equal to a thickness of the conductive pad <NUM> such that the pad is substantially flush with the inner surface <NUM> of the header <NUM>. The conductive pad <NUM> can be electrically isolated from the header <NUM> using any suitable technique or techniques. In one or more embodiments, the conductive pad <NUM> is electrically isolated from the header <NUM> by a nonconductive layer <NUM> disposed between the conductive pad on the recessed surface <NUM>. The nonconductive layer <NUM> can include any suitable nonconductive material or materials. In one or more embodiments, the nonconductive layer <NUM> is a ceramic disk disposed within the recessed surface <NUM> of the inner surface <NUM> of the header <NUM>. Further, in one or more embodiments, insulative material <NUM> can be disposed between the conductive pad <NUM> and one or more side portions <NUM> of the recessed surface. The insulative material <NUM> can include any suitable material or materials, e.g., at least one of glass, sapphire, ceramic, or epoxy or other insulative polymer. In one or more embodiments, the insulative material <NUM> and the nonconductive layer <NUM> can be the same material or materials. In one or more embodiments, the insulative material <NUM> and the nonconductive layer <NUM> are integral.

The assembly <NUM> also includes a housing <NUM> disposed within the via <NUM> between a wall portion <NUM> of the via and the feedthrough pin <NUM>. The housing <NUM> can include any suitable material or materials. Insulative material <NUM> can also be disposed between the feedthrough pin <NUM> and the housing <NUM>.

The various feedthrough header assemblies described herein can further include one or more electronic devices. For example, <FIG> is a schematic perspective view of another embodiment of a feedthrough header assembly <NUM>. All of the design considerations and possibilities described herein regarding feedthrough header assemblies 12and <NUM> apply equally to feedthrough header assembly <NUM>. One difference between assembly <NUM> and assemblies <NUM> and <NUM> is that assembly <NUM> includes a header electronic device <NUM> disposed at a first end <NUM> of feedthrough pin <NUM>. The header electronic device <NUM> is electrically connected to feedthrough pin <NUM> using any suitable technique or techniques. Further, the header electronic device <NUM> can include any suitable electronic device or devices, e.g., at least one of a capacitor, inductor, or other electrically filtering components. In one or more embodiments, the header electronic device is electrically isolated from header <NUM> using any suitable technique or techniques.

Another difference between assembly <NUM> and assemblies <NUM> and <NUM> is that a capacitor <NUM> is disposed within via <NUM> of the header <NUM>. The capacitor <NUM> can include any suitable capacitor and can be electrically connected to the pin <NUM> and the header <NUM> using any suitable technique or techniques. In one or more embodiments, an inner surface <NUM> of the capacitor <NUM> can be electrically connected to the pin <NUM>, and an outer surface <NUM> of the capacitor can be electrically connected to the header <NUM>.

<FIG> is a schematic cross-section view of another embodiment of a feedthrough header assembly <NUM>. All of the design considerations and possibilities described herein regarding feedthrough header assemblies <NUM>, <NUM>, <NUM>, and <NUM> apply equally to feedthrough header assembly <NUM>. One difference between assembly <NUM> and assemblies <NUM>, <NUM>, <NUM>, and <NUM> is that feedthrough pin <NUM> and contact <NUM> are integral. An insulating layer or disk <NUM> can be disposed between the contact <NUM> and a recessed surface <NUM> of header <NUM> to electrically isolate the contact <NUM> from the header. In one or more embodiments, disk <NUM> can be a ceramic disk. Further, an insulative material <NUM> such as glass can be disposed between one or more portions of the feedthrough pin <NUM> and via <NUM> to electrically isolate the feedthrough pin from the header <NUM>. In one or more embodiments, insulative material <NUM> can instead be disposed between the recessed sidewalls of the recessed surface <NUM> and the contact <NUM>.

The various embodiments of feedthrough header assemblies described herein can include any suitable number of feedthrough pins, e.g., two, three, four, five, or more feedthrough pins. For example, <FIG> are various views of another embodiment of a pacing device <NUM>. All of the design considerations and possibilities described herein regarding implantable medical device <NUM> of <FIG> apply equally to the implantable medical device <NUM> of <FIG>.

One difference between device <NUM> and device <NUM> is that device <NUM> includes four feedthrough pins <NUM> that extend from an endcap <NUM> of the device. Each of the feedthrough pins <NUM> can be electrically connected to an electronic layer or layers of an electronics module (e.g., one or more electronic layers <NUM> of electronics module <NUM> of <FIG>). For example, each of the feedthrough pins <NUM> can have a solder joint <NUM> that connects the pin to an electronic layer. Further, each of the feedthrough pins <NUM> can be disposed within a via <NUM> that extends through header <NUM>. In one or more embodiments, two or more of the feedthrough pins <NUM> can be disposed in the same via <NUM> and electrically isolated using an insulating material. In one or more embodiments, each feedthrough pin <NUM> can be disposed in its own respective via <NUM>. Further, each of the feedthrough pins <NUM> can extend beyond an outer surface of the header <NUM> as shown in <FIG> regarding feedthrough pin <NUM> and header <NUM>.

The various embodiments of pacing devices, electronic modules, and feedthrough header assemblies described herein can be manufactured utilizing any suitable technique or techniques. For example, <FIG> is a flowchart of one embodiment of a method <NUM> for forming the pacing device <NUM>. Although described regarding pacing device <NUM> of <FIG>, the method can be utilized to form any suitable implantable medical device.

At <NUM>, the feedthrough pin <NUM> can be disposed through the via <NUM> of the conductive header <NUM> using any suitable technique or techniques. In one or more embodiments, a portion of the feedthrough pin <NUM> adjacent to the inner surface <NUM> of the conductive header <NUM> can be removed such that an end surface at the first end <NUM> of the feedthrough pin is in a plane defined by the inner surface <NUM> of the conductive header. Any suitable technique or techniques can be utilized to remove the portion of the feedthrough pin <NUM>, e.g., the first end <NUM> can be planarized. In one or more embodiments, the inner surface <NUM> can also be planarized along with the first end <NUM> of the feedthrough pin <NUM>.

At <NUM>, one or more contacts <NUM> can be disposed on the inner surface <NUM> of the header <NUM> such that it is electrically connected to the header. Any suitable technique or techniques can be utilized to dispose the one or more contacts <NUM> on the inner surface <NUM>. In one or more embodiments, a seed layer (e.g., seed layer <NUM> of <FIG>) can be disposed on the conductive inner surface <NUM> of the conductive header <NUM>, and a conductive layer (e.g., conductive layer <NUM> of <FIG>) can be disposed on the seed layer (e.g., by sputtering), the seed layer and conductive layer can be patterned using any suitable technique or techniques, and a solder ball or contact pad (e.g., solder ball <NUM> of <FIG>) can be disposed on the patterned conductive layer. In one or more embodiments, the seed layer can be patterned prior to deposition of the conductive layer. In one or more embodiments, the seed layer and conductive layer can be patterned together.

At <NUM> one or more electronic components <NUM> of one or more electronic layers <NUM> can be electrically connected to the contact <NUM> such that the electronic component is electrically connected to the header <NUM>. The major surface <NUM> of the substrate <NUM> of the electronic layer <NUM> (i.e., the second major surface) faces the conductive inner surface <NUM> of the header <NUM> without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header. The feedthrough pin <NUM> can also be electrically connected to one or more electronic layers <NUM> using any suitable technique or techniques.

At <NUM>, the header <NUM> can be connected to the first end <NUM> of the elongated tubular housing <NUM> such that the electronics module <NUM> (e.g., one or more electronic layers <NUM>) is disposed within the housing. Any suitable technique or techniques can be utilized to connect the header <NUM> to the first end <NUM> of the housing <NUM>. In one or more embodiments, the endcap <NUM> is connected to the header <NUM>, where the end cap defines the first end <NUM> of the housing <NUM>.

At <NUM>, a power source (e.g., battery <NUM>) can be electrically connected to one or more of the electronic layers <NUM>, e.g., by pressing a first side of the electronics module <NUM> against the electrical contact assembly <NUM>. The first portion <NUM> of the housing <NUM> can be disposed over the electronics module <NUM> and connected to the second portion <NUM> of the housing <NUM> using any suitable technique or techniques, e.g., laser bonding. Further, the end cap <NUM> can be connected to the header <NUM> of the feedthrough assembly <NUM> of the electronics module <NUM> using any suitable technique or techniques, e.g., welding.

Computer-readable media may include computer-readable storage media, which corresponds to a tangible medium such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

Claim 1:
An electronics module comprising:
a feedthrough header assembly (<NUM>) comprising:
a conductive header (<NUM>) comprising a conductive inner surface (<NUM>), an outer surface (<NUM>), and a contact disposed on the inner surface and electrically connected to the header; and
a feedthrough pin (<NUM>) disposed within a via (<NUM>) that extends through the header between the inner surface and the outer surface of the header, wherein the feedthrough pin is electrically isolated from the header and comprises a first end (<NUM>) adjacent to the inner surface of the header and a second end (<NUM>) adjacent to the outer surface of the header; and
an electronic layer (<NUM>) comprising a substrate and an electronic component (<NUM>) disposed on or within the substrate, wherein the electronic component is electrically connected to the contact of the conductive header such that the electronic component is electrically connected to the header, and further wherein a major surface of the substrate of the electronic layer faces the conductive inner surface of the header without any intervening nonconductive layers disposed between the major surface of the substrate and the conductive inner surface of the header.