Component carrier and method of manufacturing a component carrier

Abstract

A component carrier and a method of manufacturing a component carrier are provided. The component carrier comprises: a stack (102) having a front side (104) and a rear side (106) and comprising a plurality of electrically conductive layer structures, and a plurality of stacked electrically insulating layer structures (108); a through-hole (110) connecting two conductive layer structures (130) of the plurality of conductive layer structures, the through-hole (110) being narrower at an inner portion (185) of the through-hole (110) than at an outer portion (187, 189) of the through-hole (110), and the through-hole (110) extending through the plurality of electrically insulating layer structures (108), such that a sidewall (154) of each of the plurality of electrically insulating layer structures (108) defines a respective portion of the via (110); and a conductive filling medium (112), wherein at least one part of the through hole (110) is filled with the conductive filling medium (112).

Description

[0001] This application is a divisional application of an invention patent application with an application date of September 27, 2019, application number 2019109229199, and invention name “Component carrier with through holes extending through multiple dielectric layers”. Technical Field

[0002] The invention relates to a component carrier and a method for producing a component carrier. Background Art

[0003] In the context of the increasing product functionality of component carriers equipped with one or more electronic components and the increasing miniaturization of such components as well as the increasing number of components to be mounted on component carriers such as printed circuit boards, more powerful array-like components or packages with several components having a plurality of contacts or connections with decreasing spacing between these contacts are increasingly being used. Removing the heat generated by such components and the component carriers themselves during operation is becoming an increasingly prominent problem. At the same time, the component carriers should be mechanically strong and electrically reliable in order to be able to operate even under harsh conditions. All these requirements are closely related to the continuous miniaturization of component carriers and their construction.

[0004] Furthermore, it may be advantageous to effectively contact conductive layer structures and / or components embedded in the component carrier with suitable quality.For this purpose and others, it may be advantageous to form vias that can be filled with copper. Summary of the invention

[0005] It may be necessary to manufacture component carriers with suitable electrical reliability.

[0006] According to an exemplary embodiment of the present invention, a component carrier is provided, which comprises: a stack having a front side and a back side and comprising a plurality of stacked electrically insulating layer structures (wherein different electrically insulating layer structures in the electrically insulating layer structures may be made of the same material or may be made of different materials); a through hole (in particular a through hole made by laser processing, or alternatively by any other suitable method such as plasma processing), which is narrower (in particular the narrowest) in its inner (inner, inside) part than in its outer (outer, outside) part and extends through the plurality of electrically insulating layer structures (in particular completely extends through all of the plurality of electrically insulating layer structures). This can be achieved in the following way: the side walls of each of the electrically insulating layer structures define a corresponding part of the through hole (in particular in such a way that each of the electrically insulating layer structures directly contributes to the formation and definition of the through hole), and a conductive filling medium (which may be composed of one or more plated substructures, for example made of copper) fills at least a part of the through hole.

[0007] According to another exemplary embodiment of the present invention, a method for manufacturing a component carrier is provided, wherein the method comprises: providing a stack having a front side and a rear side and comprising a plurality of stacked electrically insulating layer structures; performing a first laser drilling from the front side into the electrically insulating layer structures (in particular into a first portion of the electrically insulating layer structures), thereby forming a blind hole in the stacked electrically insulating layer structures; thereafter performing a second laser drilling from the rear side into the electrically insulating layer structures (in particular into a second portion of the electrically insulating layer structures), thereby extending the blind hole into a laser via. The laser via may be formed to be narrower at its inner portion than at its outer portion. Furthermore, the laser via may extend through the plurality of electrically insulating layer structures such that the sidewalls of each electrically insulating layer structure of the electrically insulating layer structures define a corresponding portion (or portion or section) of the laser via. The method may further comprise at least partially filling the laser via with a conductive filling medium.

[0008] In the context of the present application, the term "component carrier" may particularly denote any support structure on which and / or in which one or more components can be accommodated for providing mechanical support and / or electrical connection. In other words, the component carrier may be configured as a mechanical and / or electronic carrier for the components. In particular, the component carrier may be one of a printed circuit board, an organic interposer and an IC (integrated circuit) substrate. The component carrier may also be a hybrid board combining different component carriers of the above-mentioned types of component carriers.

[0009] In the context of the present application, the term "layer structure" may particularly denote a continuous layer, a patterned layer or a plurality of non-continuous islands in a common plane.

[0010] In the context of the present application, the term "stack" may particularly denote an arrangement of a plurality of planar layer structures mounted in parallel one on top of the other.

[0011] In the context of the present application, the term "through hole" may particularly denote a hole that extends completely through the entire layer structure, and the hole may be particularly and preferably formed by laser processing. Therefore, the through hole may be a laser through hole. Such a through hole may have, for example, two opposite tapered portions extending from two opposite main surfaces of the electrically insulating layer structure. For example, a through hole may be manufactured by a combination of laser irradiation from the front and back sides of the layer structure, i.e., from two opposite main surfaces of the layer structure. One or more laser irradiations may be performed from each of these sides. It is also possible to form a through hole by laser processing from only one main surface. In addition, the formation of the through hole may also be achieved by other methods other than laser processing, for example, by plasma processing.

[0012] According to an exemplary embodiment of the present invention, a through hole (preferably a laser through hole) partially or completely filled with a conductive filling medium can be manufactured, which extends through a plurality of different electrical insulating layer structures. Unexpectedly, stacking different electrical insulating layer structures made of even different materials and / or different thicknesses will not hinder the formation of a common through hole extending through all of the electrical insulating layer structures, especially by first drilling from the front side of the multi-dielectric layer stack with a corresponding laser beam and then from the back side. Therefore, it has been demonstrated that through holes can be formed even in a stack of electrical insulating layer structures with heterogeneous properties. This is very advantageous because forming a single through hole running through a plurality of dielectric layers and filling the through hole with a conductive filling medium significantly increases the design freedom of the circuit designer to configure or adjust the characteristics of the component carrier. For example, each dielectric layer can be functionalized separately for adjusting the desired characteristics of the component carrier and the through hole. This can include, for example, functionalizing the dielectric layer by enhancing heat removal during drilling (preferably laser drilling), reducing carbonization, improving the irradiation of the stack with a laser beam or the like, etc. Very advantageously, the produced through-hole can be narrower in its inner part than in its outer part, i.e. can deviate from a completely cylindrical shape. By utilizing such a locally narrowed bottleneck of the inner part of the through-hole, it can be ensured that the procedure of filling the through-hole with the conductive filling medium properly creates a bridge structure around the narrowed (or even the narrowest) part of the through-hole inside the stack. It has been proven that such a geometry properly prevents the formation of undesirable voids in the conductive filling medium. Such voids may degrade the electrical and / or thermal properties of such conductive filling medium. In addition, advantageously, the inner sidewalls of each of the opened (particularly laser-drilled) electrically insulating layer structures can contribute to directly defining or limiting the corresponding part of the through-hole in the stack. Therefore, in particular, it is possible to directly laser drill through the stacked electrically insulating layer structure to form a through-hole during through-hole formation (particularly laser drilling), without the need to form a dielectric inlay or the like in the stack through which the laser (or any other through-hole forming entity) extends. Directly drilling (preferably with a laser beam) through the stacked electrically insulating layer structure to form inner sidewalls of the electrically insulating layer structure, which then completely define respective vertical portions of the through-holes, may significantly simplify the manufacturing process and may reduce complexity.

[0013] Next, further exemplary embodiments of the component carrier and the method will be explained.

[0014] In one embodiment, the stack comprises a core, which in particular comprises a fully cured dielectric material. Such a core may be made, for example, of FR4 material. The core may be a thick dielectric layer of a fully cured material that no longer solidifies when the temperature rises or mechanical pressure is applied.

[0015] In one embodiment, the core is free of copper foil. Thus, a pure dielectric core can be the basis for forming the vias.

[0016] In one embodiment, the dielectric material of any electrical insulating layer structure of the stack includes one or more of the following:

[0017] - resins (especially epoxy resins) and reinforcing particles (especially glass fibers), especially prepreg materials;

[0018] - Epoxy derivatives (especially Laminated film);

[0019] -Glass;

[0020] -ceramics.

[0021] From this list it can be deduced that extremely different dielectric materials can be combined in a plurality of dielectric layer stacks through which common vias are formed. Thus, the high degree of freedom in selecting the stack material also allows the properties of the component carrier to be appropriately adjusted without compromising the freedom to form plated vias even through the plurality of dielectric layers as a whole.

[0022] In one embodiment, the stack additionally includes an adhesion promoting layer. Such an adhesion promoting layer may be configured to promote adhesion between two electrically insulating layers and / or conductive layers of the stack connected by the adhesion promoting layer. Such an adhesion promoting layer may also be electrically insulating and may be one of a plurality of electrically insulating layer structures through which a common through hole is formed. The adhesion promoting layer may have a thickness in a range between 0.2 μm and 2 μm.

[0023] In one embodiment, the stack comprises a core composed of FR4, the core composed of FR4 being covered on its two opposite major surfaces with The FR4 core can provide stability. In particular, an ABF layer connected to such a core can be very advantageous as one of a plurality of electrically insulating layer structures through which a common via is formed. ABF can have excellent electrical insulation properties and thermal conductivity properties and can be appropriately compatible with high frequency applications. In addition, such ABF material can be free of glass fibers, which can simplify the formation of vias extending through such ABF layers.

[0024] In an embodiment, the total thickness of the electrically insulating layer structure of the stack considered together is in the range between 30 μm and 250 μm, in particular in the range between 70 μm and 200 μm. Thus, even with relatively thick multiple dielectric layers, a single common via can be formed.

[0025] In an embodiment, each individual electrically insulating layer structure of the stack has a thickness of at least 10 μm, in particular at least 20 μm. Thus, the different electrically insulating layer structures may be relatively thin, but may preferably be thicker than 10 μm or even 20 μm.

[0026] In one embodiment, the stack is formed by an electrically insulating layer structure at least in a first region, which extends around the through hole from the front side to the back side. In other words, the entire through hole can be formed in the entire dielectric part of the stack, which is only formed by the electrically insulating layer structure through which the through hole extends.

[0027] Still referring to the aforementioned embodiment, in the second region (different from the first region), the electrically insulating layer structure can be separated by at least one electrically conductive layer structure. Therefore, one or more second regions of the stack can also be provided with an electrically conductive layer structure to improve the electrical connection function of the component carrier, to improve thermal performance and / or to improve mechanical stability.

[0028] In one embodiment, the component carrier comprises a component embedded in the stack. Taking into account the possibility of combining different dielectric materials in the stack through which the common through hole is formed, the characteristics of the component carrier can also be adjusted so that the components can be embedded simultaneously. The laser via formation may affect the embedding of the component. However, the component can, for example, be surrounded by elastic material of one or more of the electrically insulating layer structures, so that the component can more easily withstand the pressure applied during the through hole formation.

[0029] In one embodiment, the material of at least one of the electrically insulating layer structures is functionalized. For example, the material of at least one of the electrically insulating layer structures is functionalized to be at least one of the group consisting of: a mechanical buffer (which may have a low Young's modulus value, such as less than 10 GPa), a heat removal structure (which may have a high thermal conductivity, such as greater than 2 W / mK), and a low-loss high-frequency dielectric (which may have a low DK value). Therefore, different functionalized dielectric materials can be combined to define a stack through which a common through hole is formed. This increases the functionality of the component carrier obtained.

[0030] In one embodiment, the interface between the connected electrically insulating layer structures of the stack does not contain conductive material. For example, the stack can be arranged so that at least two electrically insulating layer structures of the plurality of stacked electrically insulating layer structures are at least partially directly connected to each other. In particular, the dielectric materials of different electrically insulating layer structures of different materials can be directly connected to each other without metal material between them.

[0031] In one embodiment, the first laser drilling may form a blind hole extending from the front side through at least a portion of at least two of the electrically insulating layer structures (e.g., the upper electrically insulating layer structure and the central electrically insulating layer structure). Then, the second laser drilling may extend through at least a portion of at least two of the electrically insulating layer structures (e.g., the lower electrically insulating layer structure and the central electrically insulating layer structure), thereby completing the through hole by connecting to the blind hole from the back side. Thus, each of the first laser drilling and the second laser drilling may extend through more than one electrically insulating layer structure.

[0032] In one embodiment, the method comprises: performing a first laser drilling extending through the entire first electrically insulating layer structure and into a portion of the second electrically insulating layer structure; and performing a second laser drilling extending through the entire third electrically insulating layer structure and into another portion of the second electrically insulating layer structure in order to complete the through hole. It is thus possible that the laser drilling passes through three (or even more) different electrically insulating layer structures. During the first drilling process from the front side, the laser irradiation can extend through the entire first electrically insulating layer and into a portion of the second electrically insulating layer structure. With the second laser irradiation from the back side, the laser through hole can extend through the entire third electrically insulating layer structure and the remaining portion of the second electrically insulating layer structure. By taking this measure, for example, a laser through hole can be formed through a central prepreg material or FR4 layer, which is covered with ABF layers on its two opposite main surfaces.

[0033] In one embodiment, the method includes covering the electrically insulating layer structure with a first conductive layer structure on the front side, and forming a first window extending through the first conductive layer structure, in particular by laser drilling or by a conformal mask. In the context of the present application, the term "window" may particularly refer to a through hole extending through the conductive layer structure as a result of processing the conductive layer structure, in particular a circular through hole. Descriptively speaking, the energy of the laser beam can remove the material of the conductive layer structure in the window area. The formation of the first window can be achieved by the same laser beam that also creates a blind hole in the first drilling procedure. Alternatively, the window can be formed by etching a through hole through the conductive layer structure. Using a laser to form a window has the advantage that no additional procedures are required for window formation. Using an etched window has the advantage that the conductive layer structure that overhangs beyond the electrically insulating layer structure can be reduced or even eliminated.

[0034] In one embodiment, the method comprises: covering the electrically insulating layer structure with a second electrically conductive layer structure at the back side, and forming a second window extending through the second electrically conductive layer structure, in particular by laser drilling or by a conformal mask. Thus, the second window on the back side can be formed in a corresponding manner to the first window on the front side, i.e. as described above.

[0035] As already mentioned, the component carrier may include a conductive filling medium that fills at least a portion of the through-hole. Preferably, the conductive filling medium may include or consist of copper. In one embodiment, the entire through-hole is filled with copper. In another embodiment, only a portion of the through-hole is filled with copper. Filling the through-hole with a conductive material may be achieved by first forming a thin seed layer of conductive material on the side walls of the electrically insulating layer structure that defines the through-hole. Such a seed layer may be formed, for example, by electroless deposition or sputtering in order to prepare the through-hole for a subsequent plating procedure. Subsequently, one or more plating procedures may be performed to first thicken the sidewalls with a conductive material, followed by forming a bridge connecting the opposite sidewalls in a substantially horizontal direction. This is followed by successively filling the remaining recesses above and below the bridge structure with further conductive filling medium such as copper.

[0036] In particular, the conductive filling material may include a bridge structure connecting the opposite side walls of the through hole defined by the electrical insulating layer structure. In the context of the present application, the term "bridge structure" may particularly refer to the following conductive structure: the conductive structure extends approximately horizontally between the opposite side walls of the through hole defined by the electrical insulating layer structure, particularly at or near the narrowest part of the through hole. For example, such a bridge structure may be formed by plating after the through hole is formed. After such a plating procedure, the previously formed through hole is only partially filled with the conductive material constituting the bridge structure, so that the bridge structure is defined by the first boundary surface in the upward direction and by the second boundary surface on the lower side. Both the first boundary surface and the second boundary surface may have a concave shape. By molding a through hole having a narrower section in the inner part compared to the outer part of the through hole, the proper formation of such a bridge structure can be promoted without undesirable gaps in its interior.

[0037] In an embodiment, the component carrier is configured as an interposer. However, since the stack with a plurality of (in particular different) electrically insulating layer structures is relatively thin, a component carrier with a stable shape can be obtained, which is optimally suitable for being configured as an interposer. For example, a plurality of through holes of the above-mentioned type extending parallel to each other and each extending through a plurality of electrically insulating layer structures and at least partially filled with a conductive filling medium can be formed in the stack to obtain an interposer with a plurality of vertical conductive paths.

[0038] In one embodiment, the first laser drilling comprises one laser shot and the second laser drilling comprises only one laser shot. This may be an advantageous approach for thinner electrically insulating layer structures and may result in an X-shaped laser via. Thus, at least a portion of the laser via is substantially X-shaped in a cross-sectional view. The substantially X-shaped laser via may be obtained by performing a single laser shot during the front side drilling and a single laser shot during the back side drilling.

[0039] In another embodiment, the first laser drilling includes one laser irradiation and the second laser drilling includes two laser irradiations. This is preferred for thicker electrically insulating layer structures and can result in two outer tapered portions being connected by a straight inner portion of the laser via. The straight portion can have different vertical lengths on different side walls. In this embodiment, at least a portion of the laser via can have a central, substantially cylindrical portion between two opposite tapered sections. With this alternative approach, the narrowest section of the laser via can be melted wider or wider by an additional third laser irradiation from the back side. In other words, a laser via having the described geometry can be obtained by first performing one laser irradiation on the front side drilling and then performing two laser irradiations during the back side drilling. This method can further improve electrical reliability.

[0040] In one embodiment, the component carrier comprises a stack of an electrically insulating layer structure and at least one electrically conductive layer structure. For example, the component carrier can be a laminate of the mentioned electrically insulating layer structure and the electrically conductive layer structure, in particular formed by applying mechanical pressure and / or heat. The mentioned stack can provide a plate-shaped component carrier that can provide a large mounting surface for the components and still be very thin and compact.

[0041] In one embodiment, the component carrier is formed as a plate. This contributes to a compact design, wherein the component carrier still provides a large base for mounting components thereon. Furthermore, a bare chip, in particular as an example of an embedded or surface mounted electronic component, can be easily assembled into or mounted on a thin plate, such as a printed circuit board, due to its small thickness.

[0042] In an embodiment, the component carrier is configured as one of the group consisting of a printed circuit board and a substrate, in particular an IC substrate.

[0043] In the context of the present application, the term "printed circuit board" (PCB) may particularly refer to a plate-like component carrier, which is formed by laminating several conductive layer structures with several electrically insulating layer structures, for example, by applying pressure and / or by applying heat. As a preferred material for PCB technology, the conductive layer structure is made of copper, and the electrically insulating layer structure may include resin and / or glass fiber, so-called prepreg materials such as FR4 materials. Through holes through the laminate are formed, for example, by laser drilling and / or mechanical drilling, and through holes are filled with conductive materials (particularly copper), thereby forming vias as through-hole connections, so that each conductive layer structure can be connected to each other in a desired manner. In addition to one or more components that can be embedded in the printed circuit board, the printed circuit board is generally configured to accommodate one or more components on one surface or two opposite surfaces of the plate-like printed circuit board. The components can be connected to the corresponding main surface by welding. The dielectric part of the PCB can be composed of a resin with reinforcing fibers (such as glass fibers).

[0044] In the context of the present application, the term "substrate" may particularly refer to a small component carrier. A substrate may be a component carrier as small as a PCB, on which one or more components may be mounted, and the substrate may serve as a connection medium between one or more chips and another PCB. For example, a substrate may have substantially the same size as a component (particularly an electronic component) to be mounted thereon (for example, in the case of a chip size package (CSP)). More particularly, a substrate may be understood as a carrier for electrical connection or electrical network, and a component carrier comparable to a printed circuit board (PCB), but the substrate has a relatively high density of lateral and / or vertically arranged connections. A lateral connection is, for example, a conductive path, and a vertical connection may be, for example, a drill hole. These lateral and / or vertical connections are arranged in the substrate, and may be used to provide electrical and / or mechanical connections between accommodated components or unaccommodated components (such as a bare wafer), particularly an IC chip and a printed circuit board or an intermediate printed circuit board. Therefore, the term "substrate" also includes an "IC substrate". The dielectric portion of the substrate may be composed of a resin having reinforcing balls (such as glass balls).

[0045] In one embodiment, the electrically insulating layer structure comprises at least one of the group consisting of: resin (such as reinforced or non-reinforced resin, for example epoxy resin or bismaleimide-triazine resin); cyanate ester; polyphenylene derivative; glass (especially glass fiber, multilayer glass, glass-like material); prepreg material (such as FR-4 or FR-5); polyimide; polyamide; liquid crystal polymer (LCP); epoxy-based laminated film; polytetrafluoroethylene (Teflon); ceramic and metal oxide. Reinforcement materials such as meshes, fibers or spheres made of glass (multilayer glass) may also be used. Although prepreg materials, especially FR4, are generally preferred for rigid PCBs, other materials may also be used, especially epoxy-based laminated films for substrates. For high-frequency applications, high-frequency materials such as polytetrafluoroethylene, liquid crystal polymers and / or cyanate ester resins, low-temperature co-fired ceramics (LTCC) or other low, very low or ultra-low DK materials may be implemented as electrically insulating layer structures in component carriers.

[0046] In one embodiment, at least one conductive layer structure comprises at least one of the group consisting of: copper, aluminum, nickel, silver, gold, palladium and tungsten. Although copper is generally preferred, other materials or coated forms of other materials are also possible, in particular coated with superconducting materials such as graphene.

[0047] At least one component may be surface mounted and / or may be embedded and may be selected from the group consisting of: a non-conductive inlay, a conductive inlay (such as a metal inlay, preferably comprising copper or aluminum), a heat transfer unit (such as a heat pipe), a light-conducting element (such as an optical waveguide or light conductor connection, an electronic component or a combination thereof). For example, the component may be an active electronic component, a passive electronic component, an electronic chip, a storage device (such as a DRAM or other data storage), a filter, an integrated circuit, a signal processing component, a power management component, an optoelectronic interface element, a light emitting diode, an optocoupler, a voltage converter (such as a DC / DC converter or an AC / DC converter), a cryptographic component, a transmitter and / or a receiver, an electromechanical transducer, a sensor, an actuator, a micro-electromechanical system (MEMS), a microprocessor, a capacitor, a resistor, an inductor, a battery, a switch, a camera, an antenna, a logic chip and an energy harvesting unit. However, other components may also be embedded in the component carrier. For example, a magnetic element may be used as a component. Such a magnetic element may be a permanent magnetic element (such as a ferromagnetic element, an antiferromagnetic element, a multiferroic element or a ferrimagnetic element, for example a ferrite core) or may be a paramagnetic element. However, the component may also be a substrate, an insert or another component carrier, for example a component carrier in a board-in-board configuration. The component may be surface mounted on a component carrier and / or may be embedded in the interior of the component carrier.

[0048] In one embodiment, the component carrier is a laminated component carrier. In such an embodiment, the component carrier is a composite of multiple layers stacked and connected together by applying pressure and / or heat.

[0049] The substrate or interposer may be composed of: at least one layer of glass; silicon (Si); or a photosensitive or dry-etchable organic material, like an epoxy-based laminate film or a polymeric compound, like polyimide or benzocyclobutene.

[0050] After processing the internal layer structure of the component carrier, one or two of the opposite main surfaces of the processed layer structure can be covered (especially by lamination) symmetrically or asymmetrically with one or more further electrically insulating layer structures and / or electrically conductive layer structures. In other words, the stacking can be continued until the desired number of layers is obtained.

[0051] After the formation of the stack of electrically insulating layer structures and electrically conductive layer structures has been completed, the resulting layer structure or component carrier may be subjected to a surface treatment.

[0052] In particular, in terms of surface treatment, an electrically insulating solder resist may be applied to one or both of the opposite main surfaces of the layer stack or component carrier. For example, a layer such as a solder resist may be formed over the entire main surface and then the solder resist layer may be patterned so as to expose one or more conductive surface portions that will be used to electrically couple the component carrier to the electronic periphery. Surface portions of the component carrier that remain covered with the solder resist, in particular surface portions containing copper, may be effectively protected from oxidation or corrosion.

[0053] In terms of surface treatment, a surface coating can also be selectively applied to the exposed conductive surface portions of the component carrier. Such a surface coating can be a conductive covering material on the conductive layer structures (such as pads, conductive tracks, etc., particularly including copper or consisting of copper) exposed on the surface of the component carrier. If such exposed conductive layer structures are left unprotected, the exposed conductive component carrier material (particularly copper) may oxidize, making the component carrier unreliable. The surface coating can then be formed as an interface between the surface mounted element and the component carrier, for example. The surface coating has the function of protecting the exposed conductive layer structures (particularly copper circuits) and enables connection processing with one or more components, for example by welding. Examples of suitable materials for surface coatings are OSP (organic solderability preservative), ENIG (electroless nickel immersion gold), gold (particularly hard gold), chemical tin plating, nickel-gold, nickel-palladium, etc.

[0054] The aspects described above and further aspects of the invention are apparent from the examples of embodiment to be described hereinafter and are explained with reference to these examples of embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A cross-sectional view of a component carrier according to an exemplary embodiment of the present invention is illustrated.

[0056] Figures 2 to 5 1 illustrates a cross-sectional view of a structure obtained during the execution of a method according to an exemplary embodiment of the present invention for manufacturing a structure having a conductive material by multiple laser irradiation processes from opposite sides and by a subsequent procedure of filling the laser vias with a conductive material. Figure 5 A component carrier with a plated laser via is shown in FIG.

[0057] Figure 6 A cross-sectional view of a component carrier according to a further exemplary embodiment of the present invention is illustrated. DETAILED DESCRIPTION

[0058] The illustration in the drawings is schematic. In different drawings, similar or identical elements are provided with the same reference signs.

[0059] Before describing the exemplary embodiments in further detail with reference to the accompanying drawings, some basic considerations upon which the exemplary embodiments of the present invention are based will be summarized.

[0060] According to an exemplary embodiment of the present invention, a through hole can be provided through multiple dielectric layers, in particular through a multilayer core. Each of the electrically insulating layer structures in the electrically insulating layer structure can be made of a homogeneous dielectric material, which can be the same or different from the dielectric material of another electrically insulating layer structure in the electrically insulating layer structure. Therefore, compared with conventional methods, through-hole drilling (especially laser through-hole drilling) can extend through more than one core dielectric layer. This can contribute to the reduction of the thickness of the package and the flexibility of the material (for example, different materials can be mixed in the core stack). Therefore, through-hole drilling can be performed through multiple core layers, and each of the multiple core layers can form a part of the side wall of the common through hole.

[0061] In particular, this can provide a core package in which a low CTE (coefficient of thermal expansion) core is combined with other dielectric materials such as ABF materials. Functionalization of each electrically insulating layer structure is possible. In particular, when the electrically insulating layer structure includes a low Young's modulus material (such as ABF), a laser via can be formed that passes through multiple electrically insulating layer structures and embeds the component in the stack. Descriptively speaking, this low Young's modulus material can act as a mechanical buffer for preventing the component from being stressed during laser processing. Moreover, in order to produce ultra-flat component carriers, the implementation of one or more ABF layers is advantageous because it suppresses warping. Therefore, the formation of the laser via is completely unaffected. It is also feasible that one of the electrically insulating layer structures through which the common laser via is formed is particularly configured for heat removal, i.e., made of a material with high thermal conductivity. Functionalized materials with high heat dissipation can also be implemented. This material with high heat dissipation due to high thermal conductivity can, for example, have a thermal conductivity greater than 0.8W / mK, particularly a thermal conductivity greater than 5W / mK. For example, a material having high thermal conductivity that may be implemented according to an exemplary embodiment of the present invention is a Rogers material, in particular a Rogers 92ML series of dielectric materials.

[0062] The laser via drilling may even extend through the entire package. This may enable the provision of a component carrier with a thinner core package. When the diameter of the narrowest portion of the laser via is appropriately chosen, providing a narrower portion in the interior of the laser via may simplify filling the laser via with a conductive filling medium, which may in particular include horizontal bridge structures connecting opposite side walls in the narrowed portion, without the risk of voids and cracks forming in the conductive filling medium.

[0063] Advantageously, such laser through-hole drilling through multiple electrically insulating layer structures can be advantageously combined with embedding components into such stacks. Another advantage is the combination of a mixed material system in a core package, and the combination of the core material with, for example, a primer resin layer. The concepts according to exemplary embodiments of the present invention can provide further core thickness reduction, particularly in packages. In exemplary embodiments, the core can use a primer resin or several (different or identical) prepreg material layers.

[0064] Advantageously, a common laser via can be formed extending through a plurality of directly or indirectly stacked electrically insulating layer structures. For example, a FR4 core can be covered with corresponding ABF layers on its two opposing major surfaces. A laser via extending through all three electrically insulating layers can be formed using front-side drilling and back-side drilling. During laser drilling, the stack of multiple electrically insulating layer structures can be covered with copper foil or not on one major surface or on two opposing major surfaces.

[0065] When there is a conductive layer structure such as a copper foil on a stack comprising a plurality of electrically insulating layer structures, a window may be first formed in the conductive layer structure before forming a laser via extending through the plurality of dielectric layer structures. Such a window may be formed by the laser drilling process itself, or may be formed by patterning the conductive layer structure, for example by etching.

[0066] Although the through-holes of the component carrier according to exemplary embodiments of the invention can also be created by other processes than laser drilling, for example by plasma processing, the exemplary embodiments described below with reference to the accompanying drawings show laser through-holes:

[0067] Figure 1 A cross-sectional view of a component carrier 100 according to an exemplary embodiment of the present invention is illustrated.

[0068] The illustrated component carrier 100 comprises a laminate stack 102 having a front side 104 and a back side 106. The stack 102 comprises a plurality (three in the embodiment shown) of stacked electrically insulating layer structures 108, which may be made of the same or different dielectric materials. Each of the planar layered electrically insulating layer structures 108 may be made of a homogeneous dielectric material. As shown, a common single laser through hole 110 extends through the plurality of electrically insulating layer structures 108. As shown in FIG. Figure 1 As shown, the through hole 110 is substantially X-shaped.

[0069] As shown, the laser through hole 110 is narrower at its inner portion 185 (e.g., the central portion, i.e., the center in the vertical direction) than at its outer portions 187, 189 (i.e., the portions of the laser through hole 110 at the front side 104 and at the rear side 106). This shape of the laser through hole 110 can be illustrated, for example, by referring to Figure 2 and Figure 3 The conductive filling medium 112 such as copper fills the laser via 110. With particular reference to Figure 5 , it will also be described how to fill the conductive filling medium 112 into the laser via 110 without excessive voids (voids that may degrade electrical and / or thermal conductivity and may promote the formation of undesirable cracks). Descriptively speaking, filling the laser via 110 with the conductive filling medium 112 specifically involves forming a bridge structure (compare Figure 5 Providing the narrowest portion for the laser via 110 in the center of the stack 102 significantly simplifies the proper shaping of the bridge structure 181 and thus facilitates substantially void-free filling of the laser via 110 with the conductive filling medium 112.

[0070] An electrically conductive layer structure 130 (eg copper foil) may be connected (eg laminated or plated) on the top side and the bottom side of the component carrier 100 .

[0071] You can also Figure 1 As can be seen in FIG. 1 , the laser via 110 extends through the plurality of electrical insulating layer structures 108, such that the sidewall 154 of each of the electrical insulating layer structures 108 defines a corresponding portion of the laser via 110. Descriptively, different dielectric materials of different electrical insulating layer structures 108 (each of the electrical insulating layer structures is made of a homogeneous dielectric material) can define different portions of the sidewall 154 of the laser via 110. In other words, the laser via 110 can be formed by irradiation with a laser (compare FIG. 1 ). Figure 2 and Figure 3 ) is directly formed in the planar electrically insulating layer structure 108 by directly removing the dielectric material of the electrically insulating layer structure 108. Very advantageously, it may not be necessary to tediously form a dielectric inlay in the electrically insulating layer structure 108 before starting the laser drilling. This can significantly simplify the production of component carriers by forming laser through-holes extending through a plurality of electrically insulating layer structures 108.

[0072] In the illustrated embodiment, the stack 102 includes a core 114 made of a fully cured dielectric material such as FR4. The material of the core 114 includes a fully cured (i.e., cross-linked) epoxy resin with reinforcing particles such as glass fibers therein. As shown, the core 114 does not contain copper foil and is only composed of dielectric material. Therefore, the dielectric material of the central electrical insulation layer structure 108 of the stack 102 can include a cured prepreg material, i.e., FR4.

[0073] In contrast, the two outer conductive layer structures 108 may be made of epoxy derivatives such as However, other materials of the electrically insulating layer structure 108 may be glass or ceramic. Between adjacent ones of the electrically insulating layer structures 108 , the stack 102 may include one or more adhesion promoting layers 116 (as shown in detail 183 ).

[0074] As shown, the stack 102 thus comprises a core 114 made of, for example, FR4 as a central electrically insulating layer structure 108, which is covered on its two opposite main surfaces with respective further electrically insulating layer structures 108, for example made of Made of laminated film.

[0075] For example, the total thickness D of the electrically insulating layer structures 108 of the stack 102 when considered together can preferably be in the range between 70 μm and 200 μm. Each individual electrically insulating layer structure in the electrically insulating layer structures 108 of the stack 102 has a thickness d1, d2, d3 in turn. For example, d2 can be in the range between 50 μm and 100 μm. In contrast, d1 and d3 (in particular d1=d3) can be in the range between 10 μm and 50 μm, but can be less than d2.

[0076] As shown, component 122 is embedded in stack 102. For example, component 122 can be a semiconductor wafer. In the embodiment shown, component 122 is embedded in core 114. For example, component 122 can be surrounded by a flexible mechanical buffer structure 179, i.e., a dielectric material with a low Young's modulus value (e.g., below 10 GPa). This can reduce the stress applied to component 122 during, for example, laser drilling.

[0077] The material of at least one of the electrically insulating layer structures 108 may also be functionalized. Preferably, different electrically insulating layer structures 108 may be functionalized in different ways. For example, the material of one electrically insulating layer structure 108 may be configured as a mechanical buffer. Another electrically insulating layer structure 108 may be functionalized to facilitate heat removal. Yet another electrically insulating layer structure 108 may be functionalized to achieve low losses at high frequencies. A single electrically insulating layer structure 108 may also include more than one function.

[0078] Figure 1 The component carrier shown in has the advantage that the laser through-hole 110 is formed through three directly connected electrically insulating layer structures 108. For example, the central and thickest electrically insulating layer structure 108 can be a core 114 made of FR4. The two thinner electrically insulating layer structures 108 attached to the two opposite main surfaces of the thickest central electrically insulating layer structure 108 can be, for example, ABF layers. For example, an RCC (resin coated copper) layer with a filler of less than 5 μm in size can be used. Laser drilling processing (see below) Figures 2 to 4 1) and the process of filling the laser via 110 with the conductive filling medium 112 (see below). Figure 5 The core is described in more detail herein without being damaged by the three electrically insulating layer structures 108, which are made of different dielectric materials and thus form dielectric material interfaces between them. Very advantageously, drilling can be performed first through the ABF layer and then through the FR4 layer (or vice versa) to implement the ABF layer for stability and buffering. However, using a material with the same properties for the entire core may make the creation of the through-holes more energy-consuming, time-consuming and / or wasteful.

[0079] Figures 2 to 4 A cross-sectional view of a structure obtained during the execution of a method according to an exemplary embodiment of the present invention for manufacturing a structure having a plurality of laser irradiations from opposite sides is illustrated. Figure 3 and Figure 4 Component carrier 100 is shown in FIG. 1 , which has a laser via 110 extending through two stacked electrically insulating layer structures 108 . Figure 5 The correspondingly formed component carrier 100 is shown after filling the laser via 110 with an electrically conductive filling medium 126 , preferably copper.

[0080] Reference Figure 2 , a first laser irradiation corresponding to a first laser beam 168 is directed from the front side 104 onto a double-layer electrically insulating layer structure 108, which is covered on its two opposite main surfaces with a corresponding conductive layer structure 130. The dielectric materials of the individual electrically insulating layer structures 108 directly connected to each other at the interface can be different or the same.

[0081] Thus, a double-layer, two electrically insulating layer structures 108 are provided, which may include a resin (such as an epoxy resin) and optional reinforcing particles such as glass fibers or glass balls. The electrically insulating layer structure 108 may, for example, be made of a fully cured FR4 material, i.e. a material having a resin that has been fully cross-linked (or at least substantially fully cross-linked, e.g. cross-linked by at least 95%) and cannot be re-melted or become flowable by applying mechanical pressure and / or heat. The electrically insulating layer structure 108 is covered on the front side 104 by a first conductive layer structure 130. The first conductive layer structure 130 may be a metal layer such as a copper foil. The electrically insulating layer structure 108 may be covered on the rear side 106 by a second conductive layer structure 130. The second conductive layer structure 130 may also be a metal layer such as a copper foil.

[0082] The vertical thickness D of the electrically insulating layer structure 108 together can be relatively small, for example, can be less than 100 μm (more specifically can be in the range between 40 μm and 60 μm). The individual electrically insulating layer structures 108 can have even smaller individual thicknesses d1 and d2. It has been found that forming laser vias through such thin electrically insulating layer structures 108 is particularly difficult in terms of reliability issues, which may be caused by phenomena such as excessive overhang 152, which will be described in further detail below. The first conductive layer structure 130 on the front side and the second conductive layer structure 130 on the back side can be metal layers, each having a thickness l1 and l2, for example, less than 5 μm, in particular between 2 μm and 4 μm.

[0083] The stack 102 consisting of the layer structures 108, 130 may be subjected to a first laser drilling from the front side 104 through the first electrically conductive layer structure 130, through the entire upper electrically insulating layer structure 108 and into the lower electrically insulating layer structure 108. More specifically, the first laser drilling extends through the entire upper electrically insulating layer structure 108 and into a portion of the lower electrically insulating layer structure 108. As a result, a first window 138 is formed as a through hole in the first electrically conductive layer structure 130. Alternatively, the first window 138 may also be formed by etching, in particular using a conformal mask. Furthermore, a blind hole 134 is formed in the electrically insulating layer structure 108 in a region adjacent to the first window 138. The blind hole 134 is delimited by a side wall 154 of the electrically insulating layer structure 108. This first laser drilling may be performed using a first laser beam 168 having a diameter or width 148, which is preferably in the range between 65 μm and 120 μm. As a result of the first laser drilling, a lateral overhang schematically indicated with reference numeral 152 may be created as a beak-shaped recess in the blind hole 134. The overhang 152 is located at the interface between: the first window 138 formed in the patterned first conductive layer structure 130, and the upper portion of the upper electrically insulating layer structure 108. Descriptively speaking, the patterned first conductive layer structure 130 with its first window 138 may extend laterally beyond the electrically insulating layer structure 108 by an amount corresponding to the overhang 152.

[0084] like Figure 2 , a through hole is formed in the first electrically conductive layer structure 130 as a first window 138 having a lateral width 150, for example, between 65 μm and 120 μm, by a first laser beam 168 having a width 148 and generated by a laser source. This first laser irradiation also forms a blind hole 134 in the electrically insulating layer structure 108. During the laser processing from the front side 104, care should be taken to select a sufficiently small laser power and / or to make the first laser irradiation sufficiently short so that the blind hole 134 does not extend as far as the second electrically conductive layer structure 130. In this case (the case where the blind hole extends as far as the second electrically conductive layer structure), undesirable phenomena such as reflections of the laser on the second electrically conductive layer structure 130 may occur, which may deteriorate the electronic properties of the manufactured component carrier 100.

[0085] Reference Figure 3, a second laser irradiation can be performed using a laser source to emit a second laser beam 170 toward the bottom side of the stack 102 for opening the second conductive layer structure 130 from the bottom side and for further removing the dielectric material of the lower electrically insulating layer structure 108. Thus, the second laser drilling extends from the back side 106 into the electrically insulating layer structure 108, thereby extending the blind hole 134 into a laser through-hole 110, which extends through the two electrically insulating layer structures 108. In other words, the second laser drilling extends to the lower part of the lower electrically insulating layer structure 108 to complete the through-hole 110.

[0086] Although not shown in the figure, Figure 2 After the described process, the stack 102 can be flipped over (i.e., can be rotated 180°) before performing a second laser drilling from the back side 106 through the second conductive layer structure 130 and through the electrically insulating layer structure 108. By taking this measure, it can be prevented that the laser source has to be moved from the top side to the bottom side of the stack 102.

[0087] By the second laser irradiation, a second window 140 extending through the second conductive layer structure 130 is formed. Alternatively, the second window 140 may be formed by etching, for example using a conformal mask. Furthermore, additional material of the electrically insulating layer structure 108 may be removed by the second laser irradiation so that the blind hole 134 is extended to a laser through hole 110 extending through the entire thickness of the electrically insulating layer structure 108. As shown, the second window 140 has a lateral width 148 that is smaller than the lateral width 150 of the first window 138. This is due to the fact that the second laser beam 170 has a lateral width 180 that is smaller than the lateral width 148 of the first laser beam 168. For example, the width 148 and the width 180 may each be in a range between 45 μm and 100 μm.

[0088] Advantageously, a second laser drilling (reference Figure 3 The first laser beam 168 with a width of 100 mm is used to perform the first laser drilling (see Figure 2 ), the second laser drilling is performed using a narrower second laser beam 170. The difference between the widths 148, 180 of the first laser beam 168 performing the first laser drilling and the second laser beam 170 performing the second laser drilling may preferably be in the range between 10 μm and 30 μm. Correspondingly, the difference between the widths 150, 148 of the first window 138 in the first conductive layer structure 130 and the second window 140 in the second conductive layer structure 130 may preferably be in the range between 10 μm and 30 μm. Advantageously, the width 180 of the second laser beam 170 may be smaller than the width 148 of the first laser beam 168. Correspondingly, the width 150 of the first window 138 may be larger than the width 148 of the second window 140.

[0089] As a result of the described manufacturing process, a certain overhang 152 may also be produced in the region of the second window 140 at the interface between the second electrically conductive layer structure 130 on the one hand and the lower electrically insulating layer structure 108 on the other hand. The overhang 152 of the first electrically conductive layer structure 130 and of the second electrically conductive layer structure 130 beyond the side walls 154 of the electrically insulating layer structure 108 which delimit the laser via 110 may preferably be no greater than 10 μm.

[0090] Furthermore, a lateral offset may be generated as a lateral distance between the center of the first window 138 and the center of the second window 140. Such a lateral offset may also exist between the center of the first tapered section 126 located in the electrically insulating layer structure 108 and caused by the first laser drilling and the center of the second tapered section 128 located in the electrically insulating layer structure 108 and caused by the second laser drilling.

[0091] It has been shown that when the second window 140 is formed to have a width 150 that is smaller than the width 148 of the first window 138, even a certain offset does not result in excessive overhang 152, especially at the first conductive layer structure 130. Therefore, in the case of performing backside laser drilling with the second laser beam 170 having a width 180 that is smaller than the width 148 of the laser beam 168 used for frontside drilling, after filling the laser via 110 with the conductive filling medium 112 (see Figure 5 ), a high electrical reliability of the manufactured component carrier 100 can be obtained (the electrical reliability may be negatively affected by the excessive overhang 152).

[0092] Surprisingly, in attempting to keep the overhang 152 small, it has proven to be very useful when the first laser drilling is performed with a lower laser power than the second laser drilling.

[0093] After the first laser irradiation has been completed with one laser irradiation from the front side (see Figure 2 ) and a second laser drilling is completed with only one additional laser shot from the back side (see Figure 3 ) thereafter, the conductive filling medium 112 may be partially or completely filled as in Figure 3 The substantially X-shaped laser aperture 110 shown in FIG. Figure 5 ). Can be used in Figure 3 The structure shown in FIG. 1 is used as a starting point to form a conductive fill medium 112 by combining electroless deposition with plating. When a simple manufacturing method is desired, Figure 3 The embodiment of is particularly advantageous because only two laser shots are sufficient to form a substantially X-shaped laser via 110 .

[0094] Alternatively, a second laser irradiation may be performed from the bottom side, thereby obtaining Figure 4 The shape of the laser via 110 is shown in FIG. This structure can be used as a basis for filling the laser via 110 with a conductive filling medium 112 in an alternative embodiment. The formation of the laser via 110 having this geometry will be referred to below. Figure 4 Described in further detail.

[0095] Reference Figure 4 , an additional third laser shot may be performed from the bottom side (or a second laser shot from the back side 106) to further open the middle diameter of the laser via 110. Descriptively, the third laser shot may be used to widen Figure 3 The narrowest section of the laser via 110, such as Figure 4 This can help to further improve electrical reliability because it simplifies filling the laser via 110 with the conductive filling medium 112. Figure 4 In the embodiment, the first laser drilling from the front side 104 (see Figure 2 ) comprises or consists of only one laser irradiation and a second laser drilling from the rear side 106 (see Figure 3 and Figure 4 ) includes or consists of two laser irradiations. Figure 4 With the additional third laser shot illustrated in , the resulting laser via 110 has a central substantially cylindrical section 124 between two opposite tapered sections 126 , 128 .

[0096] therefore, Figure 4 The implementation method and Figure 3 The embodiment of is different in that an additional third laser irradiation is performed from the rear side 106. This third laser irradiation has the following effects: Figure 3 The general X-shape shown in FIG. Figure 4 , in which a substantially cylindrical central section 124 of the laser via 110 is connected to two opposite tapered sections 126 , 128 on the front side 104 and on the rear side 106 , respectively.

[0097] Figure 5 For example, based on Figure 4 , a cross-sectional view of the component carrier 100 obtained after filling the laser via 110 with the conductive filling medium 112. Although reference will be made to Figure 4 The procedure for filling the laser via 110 with the conductive filling medium 112 is described with reference to the geometry of the laser via 110 shown in FIG. 1 , but alternatively a method according to Figure 3The X-shaped laser through hole 110 serves as the basis for this filling procedure in a corresponding manner. Therefore, the following will describe how to Figure 4 A conductive filling medium 112, preferably copper, is formed in the laser via 110 shown in FIG.

[0098] To achieve this, an electroless deposition process is preferably first performed to form a thin seed layer 144 of copper directly covering the sidewalls 154 of the electrically insulating layer structure 108 that define the laser vias 110. This can be done at Figure 5 121 in detail. The thickness of the seed layer 144 can be, for example, 0.5 μm. However, the seed layer 144 can also have a thickness of more than 1 μm and / or several cumulative seed layers can also be provided. For example, the thickness of a seed layer or the cumulative thickness of multiple seed layers can be in the range between 0.5 μm and 5 μm. When multiple seed layers are provided, they may include organic (e.g., polymer) layers, palladium layers, and / or copper layers. The formation of the seed layer 144 can facilitate subsequent electroplating procedures, as described below.

[0099] Subsequently, a further conductive material, such as copper, may be deposited by a plating procedure, in particular by electroplating or galvanic plating, on the seed layer 144. Thus, the seed layer 144 and the conductive layer structure 130 on the sidewalls 154 may be covered by a plated layer 146 of a conductive filling medium 112, such as copper. For example, the plated layer 146 may have a minimum thickness of 10 μm.

[0100] During the described plating procedure to form the plated layer 146, a conductive bridge structure 181 may be formed integrally with the plated layer 146 as a substantially horizontal portion connecting opposing sidewalls 154 of the electrically insulating layer structure 108 that define the laser via 110. As shown, the conductive bridge structure 181 is formed to be defined by a concave upper first interfacing surface 182 oriented upward or facing the front side 104, and a concave lower second interfacing surface 184 oriented downward or facing the back side 106. Forming the conductive bridge structure 181 may be performed by galvanic plating together with the plated layer 146, preferably after forming the seed layer 144. The bridge structure 181 forms a substantially horizontal bridge between opposing sidewalls 154 of the electrically insulating layer structure 108 that define the laser via 110 in the narrowest portion of the laser via 110.

[0101] Preferably, the narrowest vertical thickness w of the bridge structure 181 is at least 20 μm. In particular, when the thickness D of the electrically insulating layer structure 108 is relatively small (in particular below 100 μm), a minimum vertical thickness w of the bridge structure 181 of 20 μm ensures adequate reliability of the resulting component carrier 100 .

[0102] In addition, a first conductive bulk structure 186 is formed to fill a major portion between the first interface surface 182 and the front side 104, and a second conductive bulk structure 188 is formed to fill a major portion between the second interface surface 184 and the back side 106. This can be accomplished by performing one or more additional current plating procedures after the previous plating procedure for forming the bridge structure 181.

[0103] Therefore, it is possible to obtain the coating according to the following method by performing one or more additional plating procedures. Figure 5 Component carrier 100. Block structures 186, 188, which can be made of copper, for example, can thereby be obtained. In the embodiment shown, smaller recesses 190, 192 remain on the upper side or lower side of the component carrier 100 shown, respectively. In other embodiments, the block structures 186, 188 almost completely fill the remaining recesses above the first boundary surface 182 and below the second boundary surface 184. It should be said that it is known to the person skilled in the art that the boundary surfaces 182, 184 are clearly visible when imaging a cross section of the component carrier 100.

[0104] As a result of the described manufacturing procedure and Figure 5 The component carrier 100 illustrated in FIG. 1 thus comprises an electrically insulating layer structure 108 between a front side 104 and a rear side 106, a patterned first electrically conductive layer structure 130 covering the upper electrically insulating layer structure 108 on the front side 104, a patterned second electrically conductive layer structure 130 covering the lower electrically insulating layer structure 108 on the rear side 106, and a laser via 110 extending from a first window 138 of the first electrically conductive layer structure 130 through the electrically insulating layer structure 108 and as far as a second window 140 of the second electrically conductive layer structure 130. The laser via 110 is filled with an electrically conductive filling medium 112.

[0105] Although the description has been made based on two electrically insulating layer structures 108 through which the laser via 110 and the conductive filling medium 112 extend, Figures 2 to 5 However, a person skilled in the art will understand that such a process can also be performed with any other number of three or more electrically insulating layer structures 108 of the same or different materials and / or the same and / or different thicknesses. The free choice of the material and thickness of the individual electrically insulating layer structures 108 can allow the function of the component carrier 100 to be appropriately adjusted.

[0106] Figure 6 A cross-sectional view of a component carrier 100 according to a further exemplary embodiment of the present invention is illustrated.

[0107] Figure 6 The implementation method is different from Figure 1 Embodiments, in particular, according to Figure 6, the stack 102 is composed of the electrically insulating layer structure 108 only in the first region 197. The first region 197 extends vertically from the front side 104 to the rear side 106 and extends laterally around the laser via 110 and its conductive filling medium 112. Therefore, the entire via 110 can be formed in the entire dielectric part of the stack 102, which in the first region 197 is composed only of the electrically insulating layer structure 108 through which the via 110 extends. In addition, in a second region 199 different from the first region 197, the electrically insulating layer structure 108 is separated by a conductive layer structure 195 (here embodied as a patterned copper foil). Therefore, the second region 199 is provided with a conductive layer structure 195 to facilitate the electrical connection function of the component carrier 100, etc.

[0108] It should be noted that the term "comprising" does not exclude other elements or steps and the article "a" or "an" does not exclude a plurality. Elements described in relation to different embodiments may also be combined.

[0109] It should also be noted that reference signs in the claims should not be construed as limiting the scope of the claims.

[0110] The implementation of the invention is not limited to the preferred embodiments shown in the drawings and described above. On the contrary, various modifications using the solutions shown and according to the principle of the invention are possible, even in the case of substantially different embodiments.

Claims

1. A component carrier (100), wherein: The component carrier (100) comprises: A stack (102), the stack (102) having a front side (104) and a back side (106) and comprising a plurality of electrically conductive layer structures and a plurality of stacked electrically insulating layer structures (108); a through hole (110) connecting two electrically conductive layer structures (130) of the plurality of electrically conductive layer structures, the through hole (110) being narrower at an inner portion (185) of the through hole (110) than at an outer portion (187, 189) of the through hole (110), and the through hole (110) extending through the plurality of electrically insulating layer structures (108) such that a side wall (154) of each of the plurality of electrically insulating layer structures (108) defines a respective portion of the through hole (110); and A conductive filling medium (112) fills at least a portion of the through hole (110).

2. The component carrier (100) according to claim 1, in, The stack (102) is formed of the plurality of electrically insulating layer structures (108) at least in a first region (197), the first region extending around the through hole (110) from the front side (104) to the rear side (106); Therein, in the second region (199), the plurality of electrically insulating layer structures (108) are separated by at least one further electrically conductive layer structure (195).

3. The component carrier (100) according to claim 1 or 2, in, The through hole (110) has a cylindrical section (124) between two opposite tapered sections (126, 128); There is a lateral offset between the center of a first tapered section of the two opposite tapered sections (126, 128) in the plurality of electrical insulation layer structures (108) and the center of a second tapered section of the two opposite tapered sections (126, 128) in the plurality of electrical insulation layer structures (108).

4. The component carrier (100) according to claim 1 or 2, wherein: The conductive filling medium (112) includes a bridge structure (181) that forms a substantially horizontal bridge between opposing side walls (154) of the plurality of electrically insulating layer structures (108) that define the through hole (110) in a narrower inner portion (185) of the through hole (110).

5. The component carrier (100) according to claim 4, wherein: in, The bridge structure (181) is delimited by a concave first boundary surface (182) facing the front side (104) and a concave second boundary surface (184) facing the rear side (106).

6. The component carrier (100) according to claim 5, in, A first conductive bulk structure (186) fills a portion between the first interface surface (182) and the front side (104).

7. The component carrier (100) according to claim 5 in, A second conductive block-like structure (188) fills the portion between the second interface surface (184) and the rear side (106), so that recessed portions (190, 192) remain at the upper side and the lower side of the component carrier (100), respectively.

8. The component carrier (100) according to claim 1 or 2, in, At least one further conductive layer structure (195) of the plurality of conductive layer structures is arranged between the two conductive layer structures (130) of the plurality of conductive layer structures and in the plurality of electrically insulating layer structures (108), the through hole (110) extending through the plurality of electrically insulating layer structures (108).

9. The component carrier (100) according to claim 1 or 2, in, Different dielectric materials of different electrically insulating layer structures (108) define different portions of the sidewall (154) of the through hole (110).

10. The component carrier (100) according to claim 1 or 2, in, The through hole (110) extends through a plurality of core layers of the stack (102), each of the plurality of core layers forming a portion of a side wall of the through hole (110).

11. The component carrier (100) according to claim 10, in, The via (110) extends through more than one dielectric layer.

12. The component carrier (100) according to claim 1 or 2, in, The stacked plurality of electrically insulating layer structures (108) are made of different materials and / or the stacked plurality of electrically insulating layer structures (108) have different thicknesses.

13. The component carrier (100) according to claim 12, in, The dielectric materials of different electrically insulating layer structures (108) of different materials are directly connected to each other without metallic materials between the dielectric materials of the different electrically insulating layer structures.

14. The component carrier (100) according to claim 1 or 2, in, The stacked plurality of electrically insulating layer structures (108) are made of the same material and / or the stacked plurality of electrically insulating layer structures (108) have the same thickness.

15. The component carrier (100) according to claim 1 or 2, in, The plurality of electrically insulating layer structures (108) are separated by at least one further electrically conductive layer structure (195) of the plurality of electrically conductive layer structures.

16. The component carrier (100) according to claim 1 or 2, in, The stack (102) is provided with at least two electrically insulating layer structures of the plurality of stacked electrically insulating layer structures (108) which are at least partially directly connected to each other.

17. The component carrier (100) according to claim 1 or 2, in, The straight portion of the through hole (110) has different vertical lengths on different sidewalls formed by different electrically insulating layer structures (108).

18. The component carrier (100) according to claim 1 or 2, in, The stack (102) is covered with a copper foil on one of the opposite main surfaces, wherein the copper foil is one of the two conductive layer structures (130) in the plurality of conductive layer structures.

19. The component carrier (100) according to claim 1 or 2, in, The stack (102) is covered with two copper foils on two opposite main surfaces, wherein the two copper foils are the two conductive layer structures (130) among the plurality of conductive layer structures.

20. A method of manufacturing a component carrier (100), wherein: The method comprises: Providing a stack (102) having a front side (104) and a back side (106) and comprising a plurality of electrically conductive layer structures, and a plurality of electrically insulating layer structures (108) stacked; performing a first laser drilling from the front side (104) into the plurality of electrically insulating layer structures (108) to form blind vias (134) in the stacked plurality of electrically insulating layer structures (108); Thereafter, performing a second laser drilling from the back side (106) into the plurality of electrically insulating layer structures (108) to extend the blind hole (134) into a laser via (110), wherein the laser via (110) is narrower at an inner portion (185) of the laser via (110) than at an outer portion (187, 189) of the laser via (110), and wherein the laser via (110) extends through the plurality of electrically insulating layer structures (108) such that a side wall (154) of each of the plurality of electrically insulating layer structures (108) defines a respective portion of the laser via (110); and The laser via (110) is at least partially filled with a conductive filling medium (112) such that two conductive layer structures (130) of the plurality of conductive layer structures are connected by the laser via (110).

21. The method according to claim 20, wherein: The method comprises: performing the first laser drilling to extend through an entire first one of the plurality of electrically insulating layer structures (108) and into a portion of a second one of the plurality of electrically insulating layer structures (108); The second laser drilling is performed to extend through an entire third electrically insulating layer structure of the plurality of electrically insulating layer structures (108) and into another portion of the second electrically insulating layer structure to complete the laser via (110).

22. The method according to claim 20 or 21, wherein: The method comprises: covering the plurality of electrically insulating layer structures (108) at the front side (104) with a first electrically conductive layer structure of the two electrically conductive layer structures (130); and A first window (138) is formed extending through the first conductive layer structure.

23. The method according to claim 22, wherein: The method comprises: covering the plurality of electrically insulating layer structures (108) at the rear side (106) with a second electrically conductive layer structure of the two electrically conductive layer structures (130); and A second window (140) is formed extending through the second conductive layer structure.

24. The method according to claim 23, in, A lateral offset is formed as a lateral distance between a center of the first window (138) and a center of the second window (140).

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