Implantable medical device

Abstract

The present invention relates to an implantable medical device (1), comprising: an electronic circuit (2), a housing (3) accommodating the electronic circuit (2), and a three-dimensional electrically insulating body (4) carrying the electronic circuitry (2) and forming a portion of the housing (3).

Description

[0001] Applicant: BIOTRONIK SE & Co. KG

[0002] Date: 12.11.2025

[0003] Our Reference: 23.147P-WO

[0004] Implantable medical device

[0005] The present invention relates to an implantable medical device and to a method for producing such an implantable medical device.

[0006] Current active implantable medical devices use a metallic housing (usually titanium) on the one hand to encapsulate the electrical components and on the other hand as the return electrode for an electrode for sensing / stimulation. During sensing / stimulation, a vector is generated between the housing and the electrode. A hermetically sealed electrical feedthrough is required to conduct the electrical currents out of the housing. In case of implantable leadless pacemakers or implantable (e.g. cardiac) monitoring devices, the housing is usually partially insulated (usually with Parylene or silicone) so that a sufficiently large vector may be generated for sensing / stimulation. The metal housings are usually deepdrawn. In other solutions, they are turned. Other solutions sometimes include glass or ceramic housings that serve as insulation. The hermetically sealed electrical feedthroughs are typically produced by high-temperature soldering, in which insulators (e.g. ceramics) are brazed into a titanium flange and electrical conductors (pins) are brazed into the insulators.

[0007] However, metallic housings made of titanium, which are manufactured in a deep-drawing process, often have strong tolerance fluctuations. This is due to the residual stresses of the material, which make processing difficult and expansive. Furthermore, the shape of the housings is severely restricted by the manufacturing process (deep-drawing or turning). The components inside the titanium housing need to be protected against mechanical stress. Thus, plastic mounting frames are generally used for this purpose or the internal structure is molded. Furthermore, hermetically sealed feedthroughs are complex components that require a great deal of development work and are very expensive to procure. In addition, often quality problems arise with feedthroughs. The main reason for this is the strong effect of heat when welding a feedthrough into the housing, which may lead to cracks in the brazing or the insulators.

[0008] Further, as the metallic housing typically serves as an electrical pole (e.g., a return electrode), the components in the internal structure are typically insulated from the housing. This usually requires insulating foils or coatings in the internal structure of the implantable medical device.

[0009] In order to be able to selectively apply the coating to the housing of an implantable cardiac monitor or of a leadless pacemaker, the areas that are excluded from the coating must be masked in advance. This is usually realized using a plastic or silicone cover cap. The coating process itself is a batch process in a vacuum with long process times, which prevents a one- piece flow in production. The housings must be cleaned, treated with a primer and activated with plasma prior to coating.

[0010] Based on the above, the problem to be solved by the present invention is to provide an implantable medical device that alleviates at least some of the difficulties described above. Particularly, it is an objective of the present invention to provide an implantable medical device in which metallic housings and feedthroughs may be dispensed with.

[0011] This problem is solved by an implantable medical device having the features of claim 1 and a method for producing such an implantable medical device having the features of claim 15. Appropriate embodiments of these aspects of the present invention are stated in the corresponding dependent claims and are described below.

[0012] According to claim 1, an implantable medical device is disclosed comprising:

[0013] - an electronic circuitry, particularly comprising a conductor pattern, particularly formed by conductive tracks

[0014] - a housing accommodating the electronic circuitry, and

[0015] 23.147P-WO 12.11.2025 - a three-dimensional electrically insulating body forming a substrate for carrying the electronic circuit and forming at least a portion of the housing, wherein particularly the conductor pattern, particularly the conductive tracks, is arranged on the three- dimensional electrically insulating body.

[0016] Particularly, in an embodiment, the three-dimensional electrically insulating body forms at least a portion of a wall of the housing, particularly of a circumferential lateral wall, which portion of the wall may carry a conductive layer forming e.g. a stimulation and / or sensing electrode, an antenna, a counter pole to the antenna or a return electrode to said electrode.

[0017] Particularly, the electronic circuitry is formed by a conductor pattern, particularly formed by conductive tracks, and one or more electronic components, e.g., an integrated circuit, particularly an ASIC, a capacitor, a transformer, a resistor, a battery, etc., wherein the conductor pattern is arranged on the three-dimensional electrically insulating body. In one embodiment, the conductor pattern comprises one or more conductive pads, wherein the one or more pads are configured to be electrically connected to the one or more electronic components, e.g., by soldering or wire bonding. Particularly, the one or more electronic components may comprise solder bump for electrically connecting the one or more electronic components to the one or more conductive pads. In one embodiment, the electronic circuitry may further comprise one or more vias (vertical interconnect access) extending through the electrically insulating body, e.g., from a first surface to a second surface of the electrically insulating body. Particularly, the one or more vias may be formed by one or more through-going holes extending through the electrically insulating body filled with an electrically conductive material, e.g., a metallic material. In one embodiment, the conductor pattern comprises a first portion arranged on a first surface of the electrically insulating body and a second portion arranged on a second surface of the electrically insulating body, wherein the first portion and the second portion of the conductors patterns are electrically interconnected by one or more vias.

[0018] Particularly, the three-dimensional electrically insulating body may be metallized, i.e. applied with one or several electrically conductive layer(s) comprising a metal, at selected points or surface portions of the electrically insulating body using specific processes. The

[0019] 23.147P-WO 12.11.2025 metallization allows the three-dimensional electrically insulating body to be used as a circuit carrier. Particularly, the three-dimensional electrically insulating body takes on additional functions of the implantable medical device. This achieves a high level of functional integration and allows various components and processes to be saved as a result. Furthermore, providing a completely metallic housing may be avoided. Furthermore, due to the specific design of the three-dimensional body, there is also no need for a hermetically sealed electrical feedthrough as they are typically used in conjunction with full metallic housings. As the three-dimensional electrically insulating body as well as metallizations thereon particularly are biocompatible, there is also no need to apply coatings to the housing. Furthermore, as the three-dimensional electrically insulating body may provide a structural load bearing function (as part of the housing), the implantable medical device may be manufactured in a cost-effective manner using a high degree of automation.

[0020] According to an embodiment of the implantable medical device, the three-dimensional electrically insulating body, particularly with the electronic circuitry, is a mechatronic interconnect device (MID) also denoted as molded interconnect device in case the MID, particularly the electrically insulating body, is formed by molding, e.g., injection molding; however, the body of the MID may also be formed by 3D printing or other additive manufacturing processes.

[0021] In contrast to usual printed circuit boards that comprise flat electrically insulating substrates or boards having a planar top and bottom side, the three-dimensional electrically insulating body, particularly MID, of the present invention comprises an outside having at least one surface, e.g., a top surface, bottom surface or lateral surface, that is non-planar, i.e., extends in all three dimensions in contrast to the surfaces of usual printed circuit boards that are planar and only extend in two dimensions.

[0022] In one embodiment, the three-dimensional insulating body is a plastic body. In one embodiment, the three-dimensional insulating body is made from a thermoplastic material, particularly an injection-moldable thermoplastic material. In one embodiment, three- dimensional electrically insulating body comprises or consists of one of the following

[0023] 23.147P-WO 12.11.2025 materials: a biocompatible polymer, poly ether ether ketone (PEEK), a liquid crystal polymer (LCP), a polycarbonate (PC), a polybutylene terephthalate (PBT), polyamide (PA).

[0024] In another embodiment, the electrically insulating body is made from a ceramic material e.g., alumina (AI2O3).

[0025] Within the meaning of the present invention, the term "liquid crystal polymer" (or LCP) is used in the meaning known to and commonly used by a person skilled in the art. A "liquid crystal polymer" refers in particular to an aromatic polymer, which has highly ordered or crystalline regions in the molten state or in solution. Non-limiting examples include aromatic polyamides such as aramid (Kevlar) and aromatic polyesters of hydroxybenzoic acid, such as a polycondensate of 4-hydroxybenzoic acid and 6-hydroxynaphthalene-2-carboxylic acid (Vectran).

[0026] In an embodiment of the implantable medical device according to the invention, the three- dimensional electrically insulating body comprises an outside having a first (e.g. bottom) surface, an opposing second (e.g. top) surface, and a circumferential lateral surface, the lateral surface connecting the first surface and the second surface to one another, wherein at least one of the first surface, the second surface, the lateral surface is non-planar. Particularly, several or all of said first surface, second surface, lateral surface can be non-planar, i.e. extend in all three dimensions of space. Particularly, the first surface and / or the second surface and / or the lateral surface is / are non-planar. In one embodiment, the first surface is curved or rounded. In one embodiment, the second surface is curved or rounded. In one embodiment, the first surface and the second surface are curved or rounded.

[0027] Furthermore, in an embodiment of the implantable medical device, the electronic circuitry comprises a plurality of electronic components carried by the electrically insulating body and interconnected in an electrically conducting fashion by electrically conductive tracks arranged on the three-dimensional electrically insulating body, and optionally by one or more vias extending through the electrically insulating body.

[0028] 23.147P-WO 12.11.2025 Furthermore, in one embodiment of the implantable medical device, the first surface forms or comprises a first recess for accommodating at least one electronic component, particularly in a form-fitting manner, or for accommodating multiple electronic components of said plurality of electronic components.

[0029] According to a further embodiment of the implantable medical device, the at least one electronic component is one of: a battery, a capacitor, a resistor, a dump resistor, a transformer, an integrated circuit.

[0030] According to one embodiment, one or more electrically conductive tracks form an antenna.

[0031] Furthermore, in an embodiment of the implantable medical device, the implantable medical device comprises a fastening structure integrally formed with the three-dimensional electrically insulating body configured to mechanically fasten the at least one electronic component to the three-dimensional electrically insulating body. Particularly, the fastening structure act as a mounting frame integrally formed with the three-dimensional electrically insulating body, particularly being configured to receive and to position the at least one electronic component. Particularly, the fastening structure is formed by one or more bars protruding form a surface of the electrically insulating body, the one or more bars being configured as or providing a stop surface. Particularly, the fastening structure is formed by two bars, the two bars forming a receptacle for the at least one electronic component.

[0032] Particularly, in an embodiment, the at least one electronic component is electrically contacted by a spring or a plug-in contact integrated into the three-dimensional electrically insulating body. In one embodiment, the spring contact or the plug-in contact comprises an electrically conductive sleeve, particularly accommodating an electrically conductive spring element, the conductive sleeve being integrated into the three-dimensional electrically insulating body. Particularly the conductive sleeve by be arranged in on opening of the three- dimensional electrically insulating body and electrically contacted by one or more conductive tracks. Particularly, the spring contact or the plug-in contact is configured to receive a pin of an electronic component (e.g., a battery or a capacitor).

[0033] 23.147P-WO 12.11.2025 Furthermore, in an embodiment of the implantable medical device, the second surface forms or comprises a second recess for accommodating at least one electronic component, particularly in a form-fitting manner, or for accommodating multiple electronic components of said plurality of electronic components. Particularly the first recess may accommodate a battery while the second recess may accommodate further electronic components such as an integrated circuit, a capacitor and / or a dump resistor. In one embodiment, at least one electronic component accommodated in the first recess is electrically interconnected to at least one electronic component in the second recess by one or more vias extending through the electrically insulating body, particularly, between the first recess and the second recess.

[0034] Furthermore, according to yet another embodiment of the implantable medical device, an electrically conductive first layer is arranged on the three-dimensional electrically insulating body, particularly contacts the three-dimensional electrically insulating body, and forms a first portion of an outside of the implantable medical device.

[0035] Furthermore, in an embodiment of the implantable medical device, the electrically conductive first layer forms an antenna or an electrode, particularly an electrode configured for stimulation and / or sensing, of the implantable medical device, or a counter pole of an antenna or a return electrode of a stimulation and / or sensing electrode of the implantable medical device.

[0036] According to a further embodiment, the first layer (e.g. said antenna or said electrode) is arranged on the lateral surface of the three-dimensional electrically insulating body.

[0037] Furthermore, in an embodiment of the implantable medical device, an electrically conductive second layer is arranged on the three-dimensional electrically insulating body and particularly contacts the three-dimensional electrically insulating body and forms a second portion of an outside of the housing of the implantable medical device.

[0038] In an embodiment, the electrically conductive second layer is arranged on the lateral surface of the three-dimensional electrically insulating body.

[0039] 23.147P-WO 12.11.2025 Furthermore, in an embodiment of the implantable medical device, the second layer forms a counter pole or return electrode, particularly of the antenna or of a stimulation and / or sensing electrode of the implantable medical device.

[0040] Particularly, the second layer may be arranged opposite the first layer, particularly on opposing sides of the lateral surface of the three-dimensional electrically insulating body to maximize a sensing vector in case the first and second layer form an antenna / counter pole pair or an electrode / return electrode pair as described above.

[0041] Furthermore, in an embodiment of the implantable medical device, at least one electrode contacting layer is arranged on the three-dimensional electrically insulating body, which electrode contacting layer is electrically connected to at least one connector (e.g. a socket) integrated into the three-dimensional electrically insulating body, which connector is configured to be connected to an electrode lead (particularly to a plug of the electrode lead, the plug being insertable into the socket). In one embodiment, the at least one electrode contacting layer is electrically connected to the at least one connector by wire bonding.

[0042] Particularly, according to an embodiment, one or more electrically conductive tracks and / or the electrically conductive first layer and / or the electrically conductive second layer and / or the electrode contacting layer(s) comprises or is formed out of one of the following materials: copper, nickel, gold, platinum, palladium, titanium.

[0043] Furthermore, according to an embodiment, one or more electrically conductive tracks and / or the electrically conductive first layer and / or the electrically conductive second layer and / or the electrode contacting layer(s) comprise(s) a metal base layer arranged on the three- dimensional electrically insulating body, and a coating layer with an intermediary layer comprising nickel arranged on the metal base layer, and a top layer comprising gold, the top layer being arranged on top of the intermediary layer. Particularly, the metal base layer may comprise or may be formed out of copper. Particularly, the top gold layer renders the respective conductive track or layer biocompatible and chemically inert. The intermediary nickel layer prevents the copper atoms from migrating to the surface of the gold layer. Other

[0044] 23.147P-WO 12.11.2025 coatings (e.g. platinum, palladium, etc., instead of gold) may also be used to further increase the long-term stability of the metallization.

[0045] According to an embodiment, the three-dimensional electrically insulating body serves as an electrical insulator, particularly between said first and said second layer and / or said electrode contacting layer(s).

[0046] According to yet another embodiment, the three-dimensional electrically insulating body serves as a mounting frame configured to position and / or fix one or several components of the implantable medical device, particularly one or several electronic components of said plurality of electronic components.

[0047] Furthermore, in an embodiment of the implantable medical device, the first recess of the three-dimensional electrically insulating body is filled with a potting compound (e.g. an epoxy resin or silicone or the like) forming a portion of an outside of the housing of the implantable medical device in particular to hermetically encapsulate the at least one electronic component or said multiple electronic components. In an alternative embodiment, the first recess is covered with a plastic cover (e.g. in form of a plate) to hermetically seal the first recess Particularly, the plastic cover may be connected to the three-dimensional electrically insulating body by means of one of: laser welding, ultrasonic welding, gluing, heated riveting, etc.

[0048] Furthermore, in an embodiment of the implantable medical device, the second recess of the three-dimensional electrically insulating body is filled with a potting compound (e.g. an epoxy resin or silicone etc.) forming a portion of an outside of the housing of the implantable medical device in particular to hermetically encapsulate the at least one electronic component or said multiple electronic components. In an alternative embodiment, the second recess is covered with a plastic cover (e.g. in form of a plate) to hermetically seal the second recess. Particularly, the plastic cover may be connected to the three-dimensional electrically insulating body by means of one of the processes described above with respect to the plastic cover of the first recess.

[0049] 23.147P-WO 12.11.2025 According to a further aspect of the present invention, a method for producing an implantable medical device, particularly according to the invention, is disclosed, the method comprising the steps of: forming a three-dimensional electrically insulating body by injection molding or 3D printing so that the three-dimensional electrically insulating body forms a portion of a housing of the implantable medical device, forming electrically conductive tracks on an outside of the three-dimensional electrically insulating body for interconnecting electronic components of an electronic circuitry, and arranging electronic components on the three-dimensional electrically insulating body for forming the electronic circuit.

[0050] Particularly, the electronic components may be soldered to the respective associated electrically conductive tracks.

[0051] Particularly, a plurality of electrically conductive tracks is formed on an outside of the three- dimensional electrically insulating body, the plurality of electrically conductive tracks forming a conductor pattern, wherein the conductor pattern further comprises one or more conductive pads configured to electrically contact one or more electronic components, particularly by soldering, particularly reflow-soldering. Alternatively, one or more components may be electrically connected to the conductor pattern by an electrically conductive adhesive. In one embodiment, the method comprises the step of forming one or more vias extending through the electrically insulating body.

[0052] Particularly, the features and embodiments described in conjunction with the implantable medical device may also be used to further characterize the method according to the invention. This applies in particular to the materials selected for the three-dimensional electrically insulating body, the conductive tracks, the first and second layer and the electrode contacting layer(s), see also above.

[0053] Particularly, as described above, in an embodiment of the method, the three-dimensional electrically insulating body is generated so as to form a portion of a wall of the housing,

[0054] 23.147P-WO 12.11.2025 particularly of a circumferential lateral wall, on which portion of the wall a conductive layer may be formed, e.g. a stimulation and / or sensing electrode, an antenna, a counter pole to the antenna or a return electrode to said electrode.

[0055] Furthermore, in an embodiment of the method, the three-dimensional electrically insulating body is formed to comprise an outside having a first (e.g. bottom) surface, an opposing second (e.g. top) surface, and a circumferential lateral surface, the lateral surface connecting the first surface and the second surface to one another, wherein at least one of the first surface, the second surface, the lateral surface is non-planar. Particularly, the first surface and / or the second surface and / or the lateral surface is non-planar.

[0056] Further, according to an embodiment of the method, a first recess is provided in the first surface and at least one electronic component is accommodated therein, particularly in a form-fitting manner, or multiple electronic components are accommodated therein. Particularly, the at least one electronic component is one of: a battery, a capacitor, a resistor, a dump resistor. In one embodiment, an antenna is formed by an electrically conductive track.

[0057] According to one embodiment of the method, a fastening structure is integrally formed with the three-dimensional electrically insulating body and the at least one electronic component is particularly fastened therewith to the three-dimensional electrically insulating body.

[0058] Particularly, in an embodiment of the method, the at least one electronic component is electrically contacted by a spring or a plug-in contact integrated into the three-dimensional electrically insulating body.

[0059] According to a further embodiment of the method, the second surface forms a second recess for accommodating at least one electronic component or multiple electronic components of said plurality of electronic components. Particularly, as an example, a battery may be arranged in the first recess, while the second recess may accommodate electronic components such as capacitors and a dump resistor. In one embodiment, the method

[0060] 23.147P-WO 12.11.2025 comprises forming one or more vias extending through the electrically insulating body, particularly between the first recess and the second recess.

[0061] Furthermore, according to an embodiment of the method, an electrically conductive first layer is arranged on the three-dimensional electrically insulating body and particularly contacts the three-dimensional electrically insulating body. The electrically conductive first layer particularly forms a first portion of an outside of the housing of the implantable medical device.

[0062] According to a further embodiment of the method, the first layer forms an antenna of the implantable medical device or a counter pole of an antenna or stimulation and / or sensing electrode or return electrode of a stimulation and / or sensing electrode of the implantable medical device.

[0063] In an embodiment of the method, the electrically conductive first layer is arranged on the lateral surface of the three-dimensional electrically insulating body.

[0064] According to one embodiment of the method, an electrically conductive second layer is arranged on the three-dimensional electrically insulating body and particularly contacts the three-dimensional electrically insulating body and forms a second portion of an outside of the housing of the implantable medical device. Particularly, the second layer may be arranged opposite the electrically conductive first layer.

[0065] In an embodiment of the method, the electrically conductive first second layer is arranged on the lateral surface of the three-dimensional electrically insulating body.

[0066] Furthermore, according to an embodiment of the method, the second layer forms a counter pole, particularly of the antenna or a return electrode of a stimulation and / or sensing electrode of the implantable medical device.

[0067] According to a further embodiment of the method, electrode contacting layers are arranged on the three-dimensional electrically insulating body (e.g. in the first or second recess),

[0068] 23.147P-WO 12.11.2025 which electrode contacting layers are electrically connected to at least one connector (e.g. a socket) integrated into the three-dimensional electrically insulating body, which at least one connector is configured to be connected to an electrode lead (particularly to a plug of the electrode lead, the plug being insertable into the socket).

[0069] Further, according to an embodiment of the method, the first recess of the three-dimensional electrically insulating body is filled with a potting compound (e.g. an epoxy resin or silicone or the like) and particularly forms a portion of an outside of the housing of the implantable medical device, and particularly hermetically encapsulates the at least one electronic component or said multiple electronic components. Alternatively, in an embodiment of the method the first recess is covered with a plastic cover to hermetically seal the first recess. Particularly, the plastic cover may be connected to the three-dimensional electrically insulating body by means of one of laser welding, ultrasonic welding, gluing, heated riveting, etc.

[0070] Furthermore, in an embodiment of the method, the second recess of the three-dimensional electrically insulating body is filled with a potting compound (e.g. an epoxy resin or silicone or the like) and particularly forms a portion of an outside of the housing of the implantable medical device, too, and particularly hermetically encapsulates the at least one electronic component or said multiple electronic components. Alternatively, the second recess is covered with a plastic cover to hermetically seal the first recess. Particularly, the plastic cover can be connected to the three-dimensional electrically insulating body by means of one of laser welding, ultrasonic welding, gluing, heated riveting, etc.

[0071] Furthermore, in an embodiment of the method, the respective electrically conducting structure, i.e., the conductive tracks and / or the first layer and / or the second layer and / or the electrode contacting layer(s) may be formed by one of the following processes: laser direct structuring (LDS), two-component injection molding, MID hot stamping, direct conductor drawing.

[0072] 23.147P-WO 12.11.2025 Particularly, in LDS, additives may be mixed into the plastic. These additives may then be activated with laser energy. Particularly, metallic nuclei are formed through a physicalchemical reaction. Copper may then be built up on these nuclei in de-energized baths.

[0073] Further, in two-component injection molding, a pre-molded body is overmolded with another electrically insulating body. One of the two bodies may be metallized and the other cannot. The catalysts in the metallizable component may be exposed by wet chemical pretreatment. Metallization then takes place in currentless baths. The advantage of this method, especially for high volumes, lies in the shorter process times.

[0074] Furthermore, in MID hot stamping, an electrically conductive film may be applied to a electrically insulating body using hot stamping.

[0075] Further, in direct conductor drawing, the electrically conducting layers are additively applied to an electrically insulating body. Various processes are available for this. These include the Flamecon process, the Plasmadust process and the Aerosol-Jet process. Adhesion to the electrically insulating body may be ensured by primer or plasma activation.

[0076] As described above, the respective electrically conducting structure, e.g., the electrically conductive tracks, the electrically conductive first and / or second layer, the electrode contacting layer, which is also termed metallization, may then be coated with a nickel layer and gold layer. The gold layer renders the metallization area biocompatible and chemically inert. The nickel layer prevents the copper atoms from migrating to the surface of the gold layer. Other coatings (e.g. platinum, palladium, etc.) may also be used to further increase the long-term stability of the respective metallization.

[0077] In the following, embodiments of the present invention as well as further features and advantages of embodiments of the present invention shall be described with reference to the Figures, wherein

[0078] 23.147P-WO 12.11.2025 Fig. 1 shows a schematic cross-sectional view of an embodiment of an implantable medical device according to the invention, particularly in form of a cardiac monitoring device (ICM);

[0079] Fig. 2 shows a modification of the embodiment shown in Fig. 1, and

[0080] Fig. 3 shows an alternative embodiment of an implantable medical device according to the present invention, particularly in form of an implantable pulse generator (IPG)

[0081] Fig. 1 shows an embodiment of an implantable medical device 1 according to the present invention. Particularly, the device 1 may be a monitoring device such as an implantable cardiac monitoring device. As indicated in Fig. 1, the implantable medical device 1 comprises an electronic circuitry 2, and a power source, e.g., a battery 51, i.e., it is an active device, a housing 3 for enclosing the electronic circuit 2, and a three-dimensional electrically insulating body 4 forming a substrate for carrying the electronic circuitry 2 and forming a at least a portion of the housing 3. Preferably, the three-dimensional electrically insulating body 4 is a mechatronic or molded interconnect device MID that is e.g. formed by molding, e.g., injection molding, or 3D printing (or based on other additive manufacturing processes). The electronic circuitry 2 is particularly formed by a plurality of electrically conductive tracks 6 (forming a conductor structure), one or more vias extending through the electrically insulating body (not shown) and a plurality of electronic components 50, 51 interconnected by the plurality of electrically conductive tracks 6. The electrically conductive tracks may be arranged on the surface of the electrically insulating body 4 by selectively metallizing the body 4, e.g., with metal such as copper. The electrically conductive tracks 6 may further comprise a coating layer, comprising an intermediary layer, particularly comprising or consisting of nickel, and a top layer arranged on the intermediary layer, particularly comprising a noble metal, particularly gold, platinum or palladium. Particularly, the electrically insulating body is formed from a plastic material, particularly a thermoplastic material, particularly a injection-moldable thermoplastic material. Alternatively, the electrically insulating body 4 may be formed from a ceramic material, e.g., alumina (AI2O3).

[0082] 23.147P-WO 12.11.2025 Particularly, the three-dimensional electrically insulating body 4, particularly MID, comprises an outside having at a first (e.g. bottom) surface 41, a second (e.g. top) surface 42, and a circumferential lateral surface 43 that connects the first and second surfaces 41, 42 to one another, wherein the first and second surfaces 41, 42 are arranged on opposite sides of body 4. Particularly, at least one of these surfaces 41, 42, 43 is non-planar, particularly all of them.

[0083] Here, particularly, the three-dimensional electrically insulating body (e.g. MID) 4 serves as a circuit carrier but provides an additional function, particularly as a structural component of the housing 3. Furthermore, the implantable medical device 1 comprises a sensing electrode 60 and an electrically conductive return electrode 61 for sensing physiological signals of a person having the device 1 implanted. Particularly the sensing electrode 60 and return electrode 61 may be utilized to sense heart signals of the person. The sensing electrode 60 and the return electrode 61 may be created on two opposing ends of the body (e.g. MID) 4 by selectively metallizing the body 4 as described above and may comprise as coating as described above. A battery 51 for powering the electronic circuitry 2 may be arranged at or in the electrically insulating body 4, wherein an electrical contact to the circuitry 2 may be made via spring or plug contacts.

[0084] In detail, the three-dimensional electrically insulating body 4 may comprise a first recess 410 formed by the first surface 42 wherein the battery 51 may be arranged in the first recess 42 and held therein by a fastening structure 400 integrally formed with the three-dimensional electrically insulating body 4 which fastening structure 400 may comprise two protruding portions on opposing sides of the battery 51 to mechanically interact with the battery 51. Other components such as a capacitor and / or a resistor may be housed in the same fashion.

[0085] Furthermore, the three-dimensional electrically insulating body 4 may comprise a further second recess 420 defined by the second (e.g. top) surface 42, wherein multiple electronic components 50 may be arranged in the second recess 42 and may be connected to one another by the electrically conductive tracks 6 provided on the three-dimensional electrically insulating body 4. Particularly, the multiple electronic components 50 arranged in the second recess 42 are connected to electronic components arranged in the first recess 410, e.g., the

[0086] 23.147P-WO 12.11.2025 battery 51, by one or more vias extending through the electrically insulating body 4, particularly between the first recess 410 and the second recess 42, or from the first recess 410 to the second recess 42 (not shown).

[0087] Further, an electrically conductive first layer 60 forming the afore-mentioned sensing electrode may be arranged on the lateral surface 43 of the three-dimensional electrically insulating body 4 thereby forming a portion of the outside of the housing 3 of the implantable medical device 1. In the same manner, an electrically conductive second layer 61 forming said return electrode may be arranged on said lateral surface 43, too, so that it is arranged opposite the sensing electrode 60 and forms a portion of the outside of the housing 3 as well. Particularly, the circumferential lateral surface 43 may be formed by a circumferential lateral wall formed by the three-dimensional electrically insulating body 4 that may have a larger thickness (e.g. normal to the first and second surface 41, 42) than a middle portion of the body 4 that is located between said recesses 410, 420. Thus, the lateral surface 43 is structurally reinforced and contributes to the stability of the housing 3. Furthermore, by arranging the first and second layer (antenna and counter pole) 60, 61 on opposing portions of the lateral surface 43 of body 4, a relatively large sensing vector may be realized as indicated by the double arrow in Fig. 1.

[0088] Furthermore, for achieving a hermetically sealed housing 3, the first recess 410 may be covered by a plastic cover 90 (e.g. in form of a plate). Further, the second recess 420 may be filled by a potting compound 81 that encapsulates the conductive tracks 6 and the electronic components 50 arranged in the second recess 420.

[0089] Alternatively, as shown in Fig. 2, both recesses 410, 420 may be filled with a potting compound 81, 82 as an alternative to using the plastic cover 90. As further alternatives the potting compounds 81, 82 shown in Fig. 2 may be replaced by two plastic covers 90 of the kind shown in Fig. 1.

[0090] Fig. 3 shows an illustration of a further embodiment of an implantable medical device 1, particularly in form of an implantable pulse generator (IPG). Here too, the three-dimensional plastid body (particularly MID) 4 forms the circuit carrier on which the electronic

[0091] 23.147P-WO 12.11.2025 components 50 of the electronic circuitry 2 are placed. The battery 51 is inserted into a first recess 410 defined by the first surface 42 of the body 42. Particularly, the battery 51 may be inserted into the first recess 410 in a form -fitting manner and may be covered by a plastic cover 90 (e.g. in form of a flat plate) that hermetically seals the first recess 410 with the battery 51 therein.

[0092] Furthermore, the body 4 may comprise integrated connectors (e.g. in form of sockets) 71 for insertion of plugs of corresponding electrode leads. These connectors 71 may be contacted through an electrode connecting layer 52 that may be provided on the body 4, here in the second recess 420 formed by the second surface 42 that is arranged opposite the first surface 41. Particularly, the connectors 71 may be injected directly into the three-dimensional electrically insulating body 4, wherein the electrode connecting layers 52 may be formed adjacent the connectors. Particularly, each of the connectors 71 particularly comprise a connection surfaces 54. The electrode connector 71, particularly the connector surfaces 54, may be connected to electronic circuitry 2 via electrode connecting layer 52. A bonding process, particularly a wire bonding process may used here. Alternatively, the electrical connection may be realized using wiring ribbons and a subsequent welding process. The electrode connecting layer 52 may be formed by selective metallization as described above. Furthermore, the electrode connecting layer as well as the connecting surfaces 54 of the connectors 71 may also be coated with a gold / nickel layer when the electrically insulating body 4 is metallized as described above.

[0093] Furthermore, a return electrode 61 to the electrodes of the electrode leads may in turn be provided in form of an electrically conductive layer 61 on the lateral surface 43 of the three- dimensional electrically insulating body 4. An antenna 53 may be integrated (e.g. in the second recess 420) directly onto the electrically insulating body 4 as an additional metallization / electrically conductive layer 53.

[0094] The second recess 420 accommodating the electronic circuitry 2, particularly the electrically conductive track 6 and electronic components 50, the antenna 53, and the electrode connecting layers 52 may be filled in turn with a potting compound 81 to encapsulate these components and hermetically seal the housing 3.

[0095] 23.147P-WO 12.11.2025 The present invention achieves a high level of functional integration. The number of components of the implantable medical device 1 may be greatly reduced. Advantageously, a metallic housing can be dispensed with. The (e.g. MID) three-dimensional electrically insulating body 4 forms the outer contour of the housing of the implantable medical device. The electrically insulating body 4 can be manufactured using 3D printing or injection molding. Compared to the turning and deep-drawing processes used to manufacture current housings, the design freedom is greater. Almost any complex shape with varying wall thicknesses can be produced. It is possible to design the outer housing shape to suit the patient and the inner housing shape to suit the assembly of components. Compared to the deep-drawing process, there is also the advantage of low tolerance fluctuations. This facilitates the production of implantable medical devices and reduces rejects. The unit costs of plastic components are also more favorable than metal components. This results in miniaturized, more patient-friendly, more cost-effective housing shapes that can be manufactured reliably. Furthermore, the (e.g. MID) electrically insulating body 4 also functions as a circuit carrier. The circuit components can be assembled in a pick & place process as with conventional PCBs and then soldered using a reflow process. A conventional circuit can therefore be dispensed with.

[0096] Furthermore, regarding the implantable medical device shown Figs. 1 and 2 (e.g. ICM), the metallization may be used directly as an sensing electrode. With the implantable medical device shown in Fig. 3 (e.g. IPG), the electrode connections may be made directly from the electrically insulating body (via wiring or bonding). In both cases, this eliminates the need for an electrical feedthrough of the usual kind.

[0097] The integration of appropriate fixing elements for the components (battery, possibly capacitors, possibly dump resistor) in the three-dimensional electrically insulating body 4 also eliminates the need for a mounting frame, as used in current active implants.

[0098] As the three-dimensional electrically insulating body 4 is only selectively metallized, there is no need for measures to insulate the components of the internal structure. The use of corresponding components (insulating film) or processes (coatings) is no longer necessary.

[0099] 23.147P-WO 12.11.2025 Furthermore, the selective metallization of the electrically insulating body 4 eliminates the need for selective coating on the housing surface for ICMs and leadless pacemakers. The elimination of the listed components and processes can be directly translated into a significant reduction in group manufacturing costs.

[0100] For metallization and coating of MID components, the process chain of the PCB industry can be used, which is characterized by a high degree of standardization and a high-volume scope.

[0101] 23.147P-WO 12.11.2025

Claims

Claims1. An implantable medical device (1), comprising:- an electronic circuitry (2), particularly comprising a conductor pattern formed by conductive tracks (6),- a housing (3) accommodating the electronic circuit (2), and- a three-dimensional electrically insulating body (4) carrying the electronic circuitry (2) and forming a portion of the housing (3), wherein particularly the conductive tracks (6) are arranged on the three-dimensional electrically insulating body (4).

2. The implantable medical device according to claim 1, wherein the three-dimensional electrically insulating body (4) and the electronic circuitry (2) form a mechatronic interconnect device (MID).

3. The implantable medical device according to claim 1 or 2, wherein the three- dimensional electrically insulating body (4) comprises an outside having a first surface (41), an opposing second surface (42), and a circumferential lateral surface (43), the lateral surface (43) connecting the first surface (41) and the second surface (42) to one another, wherein at least one of: the first surface (41), the second surface (42), the lateral surface (43) is non-planar, particularly curved or rounded.

4. The implantable medical device according to one of the preceding claims, wherein the electronic circuitry (2) comprises a plurality of electronic components (50, 51) carried by the three-dimensional electrically insulating body (4) and interconnected by electrically conductive tracks (6) arranged on the three-dimensional electrically insulating body (4), and optionally by one or vias extending through the electrically insulating body (4).

5. The implantable medical device according to claims 3 and 4, wherein the first surface (41) forms a first recess (410) for accommodating at least one electronic component (51) or multiple electronic components of said plurality of electronic components.23.147P-WO 12.11.20256. The implantable medical device according to claim 5, wherein the at least one electronic component is one of: a battery (51), a capacitor, a resistor, or a dump resistor, a transformer, an integrated circuit.

7. The implantable medical device according to claim 5 or 6, wherein the implantable medical device (1) comprises a fastening structure (400) integrally formed with the three-dimensional electrically insulating body (4) configured to fasten the at least one electronic component (51) to the three-dimensional plastic body (4).

8. The implantable medical device according to claim 3 or according to one of the claims 4 to 7 insofar referring to claim 3, wherein the second surface (42) forms a second recess (420) for accommodating at least one electronic component (50) or multiple electronic components of said plurality of electronic components.

9. The implantable medical device according one of the preceding claims, wherein an electrically conductive first layer (60) is arranged on the three-dimensional electrically insulating body (4) and forms a first portion of an outside of the housing (3) of the implantable medical device (1).

10. The implantable medical device according to claim 9, wherein the first layer (60) forms an antenna, a stimulation electrode, or a sensing electrode of the implantable medical device (1).

11. The implantable medical device according to one of the preceding claims, wherein an electrically conductive second layer (61) is arranged on the three-dimensional plastic body (4) and forms a second portion of an outside of the housing (3) of the implantable medical device (1), wherein particularly the second layer (61) forms a counter pole or return electrode, particularly of the antenna or of a stimulation and / or sensing electrode of the implantable medical device (1).

12. The implantable medical device according to one of the preceding claims, wherein at least one (52) is arranged on the three-dimensional plastic body (4), which at least one23.147P-WO 12.11.2025electrode contacting layer (52) is electrically connected to at least one connector (71) integrated into the three-dimensional plastic body (4), which connector (71) is configured to receive and to be connected to an electrode lead.

13. The implantable medical device according to claim 5 or one of the claims 6 to 12 insofar referring to claim 5, wherein the first recess (410) of the three-dimensional electrically insulating body (4) is filled with a potting compound (81) to encapsulate the at least one electronic component (51) or said multiple electronic components, or wherein the first recess (410) is covered with a plastic cover (90) to hermetically seal the first recess (410).

14. The implantable medical device according to claim 8 or one of the claims 9 to 13 insofar referring to claim 8, wherein the second recess (420) of the three-dimensional electrically insulating body (4) is filled with a potting compound (82) to encapsulate the at least one electronic component or said multiple electronic components, or wherein the second recess (420) is covered with a plastic cover (90) to hermetically seal the second recess (420).

15. A method for producing an implantable medical device, particularly according to one of the preceding claims, the method comprising the steps of forming a three-dimensional insulating body (4) by injection molding or 3D printing so that the three-dimensional electrically body (4) forms a portion of a housing (3) of the implantable medical device (1), forming electrically conductive tracks (6) on an outside of the three-dimensional electrically insulating body (4) for interconnecting electronic components (50) of an electronic circuitry (2) of the implantable medical device (1), and arranging electronic components (50) on the three-dimensional electrically insulating body (4) for forming the electronic circuit (2).23.147P-WO 12.11.2025

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