CN115643676A - Component carrier and method for producing a component carrier - Google Patents

Abstract

A component carrier (100) is provided, comprising: a stack comprising at least one electrically conductive layer structure (102) and at least one electrically insulating layer structure (104); an electrically conductive polymer structure (110) located on a portion of the at least one electrically insulating layer structure (104); and a metal structure (120) located on the electrically conductive polymer structure (110); wherein the upper portion (104 u) of the electrically insulating layer structure (104), at least part of the electrically conductive polymer structure (110), and the metal structure (120) form a common laterally confined layer sequence (130). Furthermore, a method of manufacturing a component carrier (100), a further component carrier (100) and a further method of manufacturing a component carrier (100) are provided.

Description

Component carrier and method for producing a component carrier

Technical Field

The present invention relates to a component carrier, and a method of manufacturing a component carrier.

Background

Against the background of the growing product functionality of component carriers equipped with one or more components and the increasing miniaturization of such components and the increasing number of components to be mounted on component carriers such as Printed Circuit Boards (PCBs), increasingly powerful array-like components or packages with several components are used, which have a plurality of contacts or connections, the spacing between which is increasingly smaller. The PCB industry is particularly faced with the task of adjusting the dimensions of the printed circuit boards produced to meet the miniaturization requirements. In addition to this, this may involve generating a fine line structure of the circuit path, for example by a Semi Additive Process (SAP).

Conventional SAP processes typically require a metal layer as a seed layer for subsequent pattern plating. Such processes also typically require flash etching (flash etching) in order to finally remove the metal seed layer, however this process step tends to affect the conductor shape and width, and limits the line and space characteristics.

Disclosure of Invention

It may be desirable to manufacture the component carrier allowing for a fine structure of the circuit path to be generated without affecting the shape and width of the conductors and the corresponding component carrier.

According to an exemplary embodiment of the invention, a component carrier is provided, comprising: a stack comprising at least one electrically conductive layer structure and at least one electrically insulating layer structure; an electrically conductive polymer structure located on a portion of the at least one electrically insulating layer structure; and a metal structure located on the electrically conductive polymer structure; wherein the upper part of the electrically insulating layer structure, the at least part of the electrically conductive polymer structure and the metal structure form a common laterally confined layer sequence.

According to another exemplary embodiment of the invention, a method of manufacturing a component carrier is provided, wherein the method comprises: providing a stack comprising at least one electrically conductive layer structure and at least one electrically insulating layer structure; forming an electrically conductive polymer structure on the at least one electrically insulating layer structure; and forming a metal structure on the electrically conductive polymer structure; wherein the upper part of the electrically insulating layer structure, the at least part of the electrically conductive polymer structure and the metal structure are formed as a common laterally confined layer sequence.

According to a further exemplary embodiment of the present invention, a component carrier is provided, comprising: a stack comprising at least one electrically insulating layer structure and a plurality of electrically conductive layer structures, the electrically conductive layer structures comprising a metal vertical through-connection (such as an at least partially tapered metal vertical through-connection) and a horizontal metal structure on the metal vertical through-connection; and an electrically conductive polymer structure at least partially between the at least one electrically insulating layer structure and the horizontal metal structure.

According to a further exemplary embodiment of the invention, a method of manufacturing a component carrier is provided, wherein the method comprises: providing a stack comprising at least one electrically insulating layer structure and a plurality of electrically conductive layer structures comprising a metal vertical through-connection (e.g. an at least partially tapered metal vertical through-connection) and a horizontal metal structure on the metal vertical through-connection; and forming an electrically conductive polymer structure at least partially between the at least one electrically insulating layer structure and the horizontal metal structure.

In the context of the present application, the term "component carrier" may particularly denote any support structure capable of accommodating one or more components thereon and/or therein to provide mechanical support and/or electrical connectivity. In other words, the component carrier may be configured as a mechanical and/or electronic carrier for the component. 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, which mixes different types of the component carriers of the above-mentioned type.

In the context of the present application, the term "electrically conductive polymer structure" may particularly denote any structure which is electrically conductive and comprises or consists of a (preferably organic) polymer material. In the latter case, i.e. in case the electrically conductive polymer structure consists of a polymer material, the polymer material itself is electrically conductive. However, it may also be advantageous in case the electrically conductive polymer structure comprises a polymer material, if any, in addition to the optional other component(s), if the polymer material itself is electrically conductive, or if the electrically conductive polymer structure comprises another electrically conductive material, such as a metal or carbon-based material (e.g. graphene or graphite), e.g. metal particles or non-metal particles (e.g. carbon (nano-) particles) embedded in the polymer material. In one embodiment, the electrically conductive polymer may be doped (i.e., the atomic structure of the polymer may be modified by chemical or electrochemical reactions to significantly enhance the conductivity of the electronically conductive polymer). Conductivity can also be increased by realizing electrically conductive (nano) particles (thus the atomic structure of the polymer and the particles remains unchanged and the overall conductivity of the composite is increased by adding particles that are more conductive than the polymer). In one embodiment, the electrically conductive polymer structure exhibits electrical conductivity sufficient to allow plating of a metal (such as copper) on the electrically conductive polymer structure. In other words, the electrical conductivity of the electrically conductive polymer structure is preferably such that the electrically conductive polymer structure can act as a seed layer for metal plating.

In the context of the present application, the term "common laterally confined layer sequence" may particularly denote a plurality of layers arranged on top of each other, such as a layer stack, which are flush with each other at least at one side of the layer stack and/or wherein no one of the layers protrudes at least at one side of the layer stack.

According to an exemplary embodiment of the invention, a method of manufacturing a component carrier is provided, wherein a conductive polymer layer is used as a seed layer for subsequent pattern plating, instead of a metal seed layer, compared to a conventional SAP process. Thus, the metal seed layer may be replaced with a conductive polymer. The conductive polymer can be eliminated ultimately (i.e., after plating of the metal structures forming the fine line structures, e.g., circuit paths) without affecting the metal structures and their traces. As a result, a very fine circuit path structure can be generated without affecting the conductor shape and width and without being limited by line and space features.

Detailed description of exemplary embodiments

In the following, further exemplary embodiments of the component carrier and of the method of manufacturing a component carrier will be explained. However, the present invention is not limited to the following detailed description of the exemplary embodiments, but they are for illustrative purposes only.

It should be noted that features described in connection with one exemplary embodiment or exemplary aspect may be combined with any other exemplary embodiment or exemplary aspect, in particular features described in connection with any exemplary embodiment of the component carrier may be combined with any other exemplary embodiment of the component carrier and any exemplary embodiment of the method of manufacturing the component carrier, and vice versa, unless specifically stated otherwise.

If an indefinite or definite article is used when referring to a singular term, such as "a", "an" or "the", the plural of that term is also included and vice versa, unless specifically stated otherwise, and "a" or the number "1", as used herein, usually refers to "only one" or "exactly one".

It should be noted that the term "comprising" does not exclude other elements or steps and, as used herein, not only includes the meaning of "comprising", "including" or "containing", but also covers the meaning of "consisting essentially of 8230; \8230, composition" and "consisting of 8230; \8230, composition".

As used herein, unless otherwise specifically indicated, the expression "at least partially", "at least part" or "at least part of" may mean at least 1% thereof, in particular at least 5% thereof, in particular at least 10% thereof, in particular at least 15% thereof, in particular at least 20% thereof, in particular at least 25% thereof, in particular at least 30% thereof, in particular at least 35% thereof, in particular at least 40% thereof, in particular at least 45% thereof, in particular at least 50% thereof, in particular at least 55% thereof, in particular at least 60% thereof, in particular at least 65% thereof, in particular at least 70% thereof, in particular at least 75% thereof, in particular at least 80% thereof, in particular at least 85% thereof, in particular at least 90% thereof, in particular at least 95% thereof, in particular at least 98% thereof, and may also include 100% thereof.

In one embodiment, the layer sequence can have undercuts (undercuts) at the electrically conductive polymer structure. When the electrically conductive polymer structure not covered by the metal structure is removed, for example by dry etching or wet etching, some of the material of the electrically conductive polymer structure covered by the metal structure may also be etched to a slight extent, so that undercuts are formed at the electrically conductive polymer structure of the layer sequence. This may especially occur if the etching technique is an isotropic rather than an anisotropic etching technique. However, it may be advantageous if the undercuts at the electrically conductive polymer structure are as small as possible.

In one embodiment, the layer sequence has an undercut at an upper part of the electrically insulating layer structure. When removing the electrically conductive polymer structure not covered by the metal structure, for example by dry etching or wet etching, not only the electrically conductive polymer structure but also, at least to some extent, the underlying (underlying) electrically insulating layer structure may also be partially etched, more particularly the upper part of the electrically insulating layer structure. Due to this partial etching of the electrically insulating layer structure, not only the upper part of the electrically insulating layer structure forms part of the common laterally confined layer sequence together with at least part of the electrically conductive polymer structure and the metal structure, but also undercuts can be formed at the upper part of the electrically insulating layer structure, in particular if the etching technique is isotropic, rather than an anisotropic etching technique. The undercut at the upper portion of the electrically insulating layer structure may serve as a mechanical interconnection region (anchoring effect). When the copper trace is laminated with another resin sheet after the trace is formed, the resin may flow in the area under the trace, e.g., filling the undercut. The tracks will be reliably stabilized and the adhesion will be increased. The undercut may in particular have a depth of not more than 7 μm. However, it may also be advantageous if the undercut at the upper portion of the electrically insulating layer structure is as small as possible. For example, if a plasma etch is used to remove the electrically conductive polymer structure, the undercut is less pronounced and may not be visible at all.

In one embodiment, the layer sequence has no undercuts at the metal structure. Thus, although some materials of the electrically conductive polymer structure and some materials of the electrically insulating layer structure may be etched to a slight extent, thereby forming undercuts at an upper portion of the electrically insulating layer structure and at the electrically conductive polymer structure of the layer sequence, the metal structure may not be influenced by the etching, so that the layer sequence may not have undercuts at the metal structure. This is particularly advantageous for maintaining the shape of the conductive traces or conductors that may ultimately be caused by the metal structure in general.

In one embodiment, the bottom part of the electrically insulating layer structure projects laterally beyond the (upper) part of the electrically insulating layer structure forming the laterally confined layer sequence. As mentioned above, when removing the electrically conductive polymer structure not covered by the metal structure, for example by dry etching or wet etching, it is possible that not only the electrically conductive polymer structure, but also, at least to some extent, the underlying (underlying) electrically insulating layer structure is also partially etched, more particularly the upper part of the electrically insulating layer structure, while the bottom part of the electrically insulating layer is not etched, thus projecting laterally beyond the (upper) part of the portion of the electrically insulating layer structure forming the laterally confined layer sequence.

In one embodiment, at least one of the at least one electrically-conductive layer structure is located under the laterally confined layer sequence (e.g., at another major surface of the component carrier opposite the major surface of the component carrier on which the at least one electrically-conductive layer structure is located) and electrically coupled with the laterally confined layer sequence. In particular, at least one of the at least one electrically conductive layer structure that is located below and electrically coupled to the laterally confined layer sequence may comprise a horizontal pad (pad) connected to the vertical through connection. As a result, electrical connections extending vertically through the component carrier can be realized.

In one embodiment, the electrically conductive polymer structure comprises at least one organic polymer material.

In one embodiment, the electrically conductive polymer structure comprises at least one polymer material selected from the group consisting of: polyfluorenes (polyfluorenes), polyphenylenes (polyphenylenes), polypyrenes (polypyrenes), polyazulenes (polyazulenes), polynaphthalenes (polynaphthalenes), polyacetylenes (polyacetylenes, PAC), poly (p-phenylene vinylene), PPV, polypyrroles (PPY), polycarboksAzoles (polycarbozoles), polyindoles (polyindoles), polyazazoles

Polyazepines, polyanilines (PANI), polythiophenes (PT), poly (3, 4-ethylenedioxythiophene) (PEDOT), poly (p-phenylene sulfide) (PPS), polyisothianaphthene (PITN), poly (benzo [ c ])]Thiophene) (poly (c)]thiophene), poly (dithiophene 3,2-b:2, 3-d-thiophene) (poly (dithieno 3,2-b:2, 3-d-thiophene)), poly (s-aminophenethiol), poly (o-aminophenol), phthalocyanine-based polymers, bipyridine-based polymers, or mixtures, combinations, or hybrids thereof.

In one embodiment, the electrically conductive polymer structure comprises at least one polymer material selected from the group consisting of: polyaniline (PANI), poly (3, 4-ethylenedioxythiophene) (PEDOT), poly (p-phenylene sulfide) (PPS), or mixtures thereof. These polymeric materials are particularly suitable for the purposes of the present invention.

In one embodiment, the electrically conductive polymer structure (110) comprises poly (3, 4-ethylenedioxythiophene) (PEDOT), a blend of PEDOT and poly (p-phenylene sulfide) (PPS) (PEDOT: PPS), or a blend of PEDOT and polystyrene sulfonate (PSS) (PEDOT: PSS).

In one embodiment, the electrically conductive polymer structure comprises at least one inorganic polymer material, such as, for example, a sulfur nitride.

In one embodiment, the electrically conductive polymer structure comprises a polymer material and (mixed or doped with) metal (nano) particles, such as copper (nano) particles. In this embodiment, the polymeric material itself need not be electrically conductive, but it may be advantageous if the polymeric material itself is electrically conductive, for example at least one of the polymeric materials exemplified above. For example, metal (nano) particles may be embedded in (a matrix of) a polymer material. The average particle size (or average particle diameter) of the metal (nano) particles may be in the range of from 1nm to less than 200nm, in particular in the range of from 5nm to 100 nm. The determination of the average particle size (or average particle diameter) is known to the person skilled in the art and can be carried out, for example, by visual microscopic observation with appropriate magnification, for example by using an electron microscope (such as transmission electron microscope, TEM) and by randomly selecting an appropriate number of particles and calculating the average of the individual particle diameters. The determination of the average particle size (or average particle diameter) can also be performed, for example, using light diffraction of an appropriate sample size and particle concentration, such as dynamic light scattering, for example using X-ray diffraction. By adding metal (nano) particles to the polymer material, the electrical conductivity of the electrically conductive polymer structure may be increased, which may improve the intended subsequent metal plating of the electrically conductive polymer structure. On the other hand, it is preferred to limit the amount of metal (nano) particles in the electrically conductive polymer structure, in particular to an amount in which the electrically conductive polymer structure can be subsequently selectively removed, i.e. without affecting any plated metal structure, e.g. such that flash etching is not required for the final removal of the electrically conductive polymer structure.

In one embodiment, the electrically conductive polymer structure has a thickness of from 0.01 μm up to less than 0.4 μm, such as from 0.02 μm up to 0.3 μm, in particular from 0.05 μm up to 0.2 μm. If the electrically conductive polymer structure is less than 0.01 μm thick, its function as a conductive seed layer for metal plating may be compromised. If the electrically conductive polymer structure has a thickness of 0.4 μm or more, further improvement in its function as a conductive seed layer for metal plating may not be achieved and/or it may be difficult to finally remove the electrically conductive polymer structure without affecting any plated metal structure.

In one embodiment, the method further comprises forming holes in the stack before and/or after forming the electrically conductive polymer structure. In particular, the hole may extend through at least one electrically insulating layer structure of the stack. The holes may be formed by laser drilling, for example by one or more laser shots from one major surface of the component carrier (typically resulting in a hole bounded by tapered sidewalls, e.g. a hole having a truncated cone shape) or from both major surfaces of the component carrier (typically resulting in a hole having an hourglass shape).

In one embodiment, the pores are formed prior to forming the electrically conductive polymer structure. By taking this measure, the main surface of the electrically insulating layer structure as well as the side walls and/or the bottom of the holes can be provided with an electrically conductive polymer structure in one process step.

In an alternative or additional embodiment, the pores may also be formed after the formation of the (first) electrically conductive polymer structure. For example, it is possible to first form the electrically conductive polymer structure on the electrically insulating layer structure, then form a hole through the (first) electrically conductive polymer structure and in or through the electrically insulating layer structure, and then form the (second) electrically conductive polymer structure on the sidewalls and/or bottom of the hole. By this two-step method for forming an electrically conductive polymer structure, the thickness of the electrically conductive polymer structure can be adjusted or controlled as desired, for example by providing (second) electrically conductive polymer structures on the sidewalls and/or bottom of the holes, which (second) electrically conductive polymer structures have a thickness which is smaller than the thickness of the (first) electrically conductive polymer structures remaining on the major surface of the electrically insulating layer structure. After filling the hole with a metallic copper structure (e.g., by plating), this configuration may effectively allow copper to diffuse in the via thus formed, which may improve the reliability of the electrical connection.

In one embodiment, the method comprises forming the electrically conductive polymer structure by sputtering, chemical coating, dispensing a paste, spin coating or printing (such as inkjet printing or 3D printing). Among other things, sputtering may be particularly advantageous for forming electrically conductive polymer structures, especially when the surface is completely covered, since the thickness of the electrically conductive polymer structure can be easily controlled or adjusted. Furthermore, printing may also be advantageous for reasons that it allows for the local application of polymers, which may render unnecessary an etching step after plating, and thus allows for a reduction in raw material consumption, such as the polymer itself, as well as chemicals used for etching. In one embodiment, the method includes forming the metal structure by plating, such as by an electrolytic or electrochemical process. Such plating processes allow for the deposition of large amounts of metal, such as copper or copper alloys, on the electrically conductive polymer structure in a very cost effective manner and may effectively fill any previously formed holes in order to provide vias or through connections through the electrically insulating layer structure. Alternatively, the electrical interconnects may also be filled with a conductive paste.

In one embodiment, the method includes removing the electrically conductive polymer structure (which is not covered or exposed by the metal structure) by dry etching and/or wet etching (such as plasma and/or chemical wet etching) after forming the metal structure (and after removing the sacrificial material, if any). In particular, the electrically conductive polymer structure may be removed by plasma etching, which has proven to be particularly suitable for selectively removing the electrically conductive polymer structure, but without substantially affecting the metal structure. Furthermore, by using plasma etching, undercuts at the electrically insulating layer structure may be kept very small or may be substantially avoided. In the context of the present application, the term "plasma etching" may particularly denote a dry etching technique which may combine a physical etching and a chemical reaction and which may include Reactive Ion Etching (RIE). If the electrically conductive polymer structure contains metal particles, these particles may need to be removed separately by wet etching (i.e. an additional wet etching step).

In an embodiment, the dry etch and/or the wet etch for removing the electrically conductive polymer structure is configured to selectively etch (only) the electrically conductive polymer structure (and the portion of the electrically insulating layer structure), but not substantially etch the metal structure. To this end, the dry etching or the wet etching may include plasma etching.

In one embodiment, the method includes forming a laterally confined layer sequence using a patterned mask of sacrificial material. To this end, a sacrificial material such as a dry film is applied (as a patterned mask or as a continuous film and then patterned) on the electrically conductive polymer structure prior to forming the metal structure and is removed, for example by stripping, after forming the metal structure.

In one embodiment, the method comprises heat treating the laterally confined layer sequence (at least one layer sequence of the metal structure and the electrically conductive polymer structure) to trigger diffusion of the metal material into or through the electrically conductive polymer structure. For example, the heat treatment may comprise heating to a temperature in the range from 50 ℃ to 300 ℃ for a period of time from 5 minutes to 120 minutes. This may be particularly advantageous at the bottom of vias filled with metallic copper structures, where, for example, diffusion of copper may effectively improve the reliability of the electrical connection between the via and the underlying electrically conductive layer structure, such as a horizontal pad.

In one embodiment, the component carrier comprises: an at least partially tapered metal vertical through-connection and a horizontal metal structure on the metal vertical through-connection; and an electrically conductive polymer structure at least partially between the at least one electrically insulating layer structure and the horizontal metal structure.

In one embodiment, another portion of the electrically conductive polymer structure is located between the at least one electrically insulating layer structure and the metal vertical through connection.

In one embodiment, a further portion of the electrically conductive polymer structure is located between the metal vertical through connection and the horizontal pad (located below the metal vertical through connection).

In one embodiment, the interface region between the metal vertical through connection and the horizontal pad comprises a mixture of a metal material and an electrically conductive polymer material. To this end, the interface region between the metal vertical through-connection and the horizontal pad may be subjected to a heat treatment, such that the metal material diffuses into or through the electrically conductive polymer structure.

In one embodiment, the metal vertical through-connection is an at least partially tapered metal vertical through-connection. For example, the at least partially tapered metal vertical through-connection has a truncated cone shape or an hourglass shape. To this end, the partially tapered metal vertical through-connection having a truncated cone shape may be obtained by forming a hole through the at least one electrically insulating layer structure by one or more laser shots from one main surface of the component carrier and then filling the hole with a metal material (e.g. by metal plating), or the partially tapered metal vertical through-connection having an hourglass shape may be obtained by forming a hole through the at least one electrically insulating layer structure by laser shots from both main surfaces of the component carrier and then filling the hole with a metal material.

In one embodiment, the method includes forming the metal vertical through-connection by at least one of mechanical drilling and laser drilling or via a photo-sensitive medium (PID), and subsequent metallization.

In one embodiment, the method comprises: an at least partially tapered metal vertical through-connection is formed by laser drilling and subsequent metal plating.

In one embodiment, the component carrier comprises a stack of at least one electrically insulating layer structure and at least one electrically conductive layer structure. For example, the component carrier may be a laminate of the mentioned electrically insulating layer structure(s) and electrically conductive layer structure(s), in particular formed by applying mechanical pressure and/or thermal energy. The mentioned stack may provide a plate-shaped component carrier which is able to provide a large mounting surface for further components and which is still very thin and compact. The term "layer structure" may particularly denote a plurality of non-continuous islands, patterned layers or continuous layers in a common plane.

In one embodiment, the component carrier is shaped as a plate. This contributes to a compact design, wherein the component carrier still provides a large base for mounting components thereon. Further, in particular, a bare die, which is an example of an embedded electronic component, can be easily embedded in a thin board such as a printed circuit board due to its small thickness.

In one embodiment, the component carrier is configured as one of the following: printed circuit boards, substrates (particularly IC substrates) and interposers.

In the context of the present application, the term "printed circuit board" (PCB) may particularly denote a plate-shaped component carrier, which is formed by laminating a number of electrically conductive layer structures with a number of electrically insulating layer structures, for example by applying pressure and/or by providing thermal energy. As a preferred material for PCB technology, the electrically conductive layer structure is made of copper, while the electrically insulating layer structure may comprise resin and/or glass fibres, so-called prepreg or FR4 material. The various electrically conductive layer structures can be connected to each other in a desired manner by: the through-holes through the laminate are formed, for example, by laser drilling or mechanical drilling, and the vias are formed as through-hole connections by filling them with an electrically conductive material, in particular copper. In addition to one or more components that may be embedded in a printed circuit board, printed circuit boards are typically configured to receive one or more components on one surface or two opposing surfaces of a plate-shaped printed circuit board. They may be attached to the respective major surfaces by welding. The dielectric portion of the PCB may be composed of a resin with reinforcing fibers, such as glass fibers.

In the context of the present application, the term "substrate" may particularly denote a small component carrier. The substrate may be a relatively small component carrier with respect to the PCB, on which one or more components may be mounted, and which may serve as a connection medium between the chip(s) and the further PCB. For example, the substrate may have substantially the same size as the component (particularly, the electronic component) to be mounted thereon (for example, in the case of a Chip Scale Package (CSP)). More specifically, a baseplate can be understood as a carrier for electrical connections or electrical networks and a component carrier comparable to a Printed Circuit Board (PCB), but with a comparatively high density in laterally and/or vertically arranged connections. The lateral connections are, for example, conductive paths, while the vertical connections may be, for example, boreholes. These lateral and/or vertical connections are arranged within the substrate and may be used to provide electrical, thermal and/or mechanical connection of a packaged or unpackaged component (such as a bare die), in particular an IC chip, to a printed circuit board or an intermediate printed circuit board. Thus, the term "substrate" also includes "IC substrate". The dielectric part of the substrate may be composed of a resin with reinforcing particles, for example reinforcing spheres, in particular glass spheres.

The substrate or interposer may comprise or consist of at least one layer of: glass, silicon (Si) and/or a photosensitive or dry-etchable organic material, such as an epoxy-based build-up material (such as an epoxy-based build-up film) or a polymer compound, such as a polyimide, polybenzoxazole or benzocyclobutene functionalized polymer.

In one embodiment, the at least one electrically insulating layer structure comprises at least one of: a resin (such as a reinforced or non-reinforced resin, such as epoxy resin or bismaleimide-triazine resin), cyanate ester resin, 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 laminate film, polytetrafluoroethylene (PTFE, PTFE-V-E, or the like), and the like,

) Ceramics and metal oxides. Reinforcing structures, such as meshes, fibers or spheres, for example made of glass (multiple layers of glass) may also be used. While prepregs, particularly FR4, are generally preferred for rigid PCBs, other materials, particularly epoxy-based laminates or photosensitive dielectric materials, may be used. 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 can be implemented in the component carrier as an electrically insulating layer structure.

In one embodiment, the at least one electronically conductive layer structure comprises at least one of: copper, aluminum, nickel, silver, gold, palladium, and tungsten. Although copper is generally preferred, other materials or coated forms thereof are possible, particularly coated with superconducting materials such as graphene.

The at least one component may be selected from: a non-electrically conductive inlay, an electrically conductive inlay (e.g., a metal inlay, preferably comprising copper or aluminum), a heat transfer unit (e.g., a heat pipe), a light guide element (e.g., a light guide or light guide connector), an optical element (e.g., a lens), 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 (e.g., 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 opto-coupler, a voltage converter (e.g., a DC/DC converter or an AC/DC converter), a cryptographic component, a transmitter and/or receiver, an electromechanical converter, a sensor, an actuator, a micro-electro-mechanical system (MEMS), a microprocessor, a capacitor, a resistor, an inductance, 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 the component. Such a magnetic element may be a permanent magnetic element (e.g. a ferromagnetic element, an antiferromagnetic element, a multiferroic element or a ferrimagnetic element, such as a ferrite core) or may be a paramagnetic element. However, the component may also be a substrate, interposer or other component carrier, for example in a board-in-board (midplane) configuration. The component may be surface mounted on the component carrier and/or may be embedded within it. Furthermore, other components may also be used as components, in particular those generating and emitting electromagnetic radiation and/or being sensitive to electromagnetic radiation propagating from the environment.

In one embodiment, the component carrier is a laminate type component carrier. In such embodiments, the component carrier is a composite of multiple layers that are stacked and joined together by the application of pressure and/or heat.

After treatment of the inner layer structure of the component carrier, one or both of the opposite major surfaces of the treated layer structure may be covered (in particular by lamination) symmetrically or asymmetrically with one or more further electrically insulating layer structures and/or electrically conductive layer structures. In other words, lamination may continue until the desired number of layers is achieved.

After completion of the formation of the stack of the electrically insulating layer structure and the electrically conductive layer structure, the obtained layer structure or component carrier may be subjected to a surface treatment.

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 the component carrier. For example, a solder resist, for example, may be formed over the entire major surface and then patterned to expose one or more electrically conductive surface portions that will be used to electrically couple the component carrier to the electronic periphery. The surface portion of the component carrier, in particular the surface portion comprising copper, which remains covered with the solder resist, can be effectively protected from oxidation or corrosion.

In the case of a surface treatment, a surface finish may also be selectively applied to exposed electrically conductive surface portions of the component carrier. Such a surface modification may be an electrically conductive covering material on exposed electrically conductive layer structures (e.g. pads, conductive tracks, etc., in particular comprising or consisting of copper) on the surface of the component carrier. If such exposed electrically conductive layer structures are not protected, the exposed electrically conductive component carrier material (in particular copper) may be oxidized, thereby reducing the reliability of the component carrier. The surface finish may then for example be formed as an interface between the surface mounted component and the component carrier. The surface modification has the function of protecting the exposed electrically conductive layer structure (in particular the copper circuit) and enabling the joining process with one or more components (for example by soldering). Examples of suitable materials for surface modification are Organic Solderability Preservative (OSP), chemical nickel immersion gold (ENIG), chemical nickel immersion palladium immersion gold (ENIPIG), gold (in particular hard gold), chemical tin, nickel-gold, nickel-palladium, etc.

The aspects defined above and further aspects of the invention are apparent from the exemplary embodiments to be described hereinafter and are explained with reference to these exemplary embodiments.

Drawings

Fig. 1A to 1G show an exemplary embodiment of a method of manufacturing a component carrier according to the present invention.

Fig. 2 shows an enlarged partial view of a component carrier according to an exemplary embodiment of the present invention.

Detailed Description

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

Before referring to the drawings, which will describe exemplary embodiments in more detail, some basic considerations will be summarized based on the exemplary embodiments in which the present invention has been developed.

According to an exemplary embodiment of the present invention, there is provided a component carrier of a fine structure allowing a circuit path to be generated without affecting a conductor shape and width, and a method of manufacturing the same. Conventionally, the SAP process requires a metal seed layer for pattern plating. However, this process requires a flash etch to eventually remove the metal seed layer, affecting the trace shape, width, and limiting the line and space characteristics. The basic idea of the invention is to replace the metal layer with a conductive polymer. The conductive polymer can be eliminated ultimately without affecting the metal conductor. Conductive polymer removal can be achieved by dry or wet processes (RIE, plasma, chemical wet etching, ion milling, lift-off processes). The conductive polymer (lamination or deposition of the conductive layer) can be applied in a controlled thickness in one step (after the via formation process) or two steps, then the via formation and finally sputtering of a very thin conductive polymer layer, which can later allow copper diffusion in the micro-vias to improve reliability. The conductive polymer layer may finally be removed by dry or wet etching in the following manner: the copper surface and thus the conductive tracks or generally the conductors are not affected but retain their shape, allowing a finer space to be obtained. As an example of a conductive polymer material, poly 3,4-ethylenedioxythiophene (PEDOT), optionally doped with copper nanoparticles, may be mentioned. In particular, electrically conducting polymers may be doped (i.e. the atomic structure of the polymer may be modified by chemical or electrochemical reactions, thereby significantly improving the conductivity of the electronically conducting polymer). The conductivity of the polymer can also be enhanced by implementing electrically conductive (nano) particles (whereby the atomic structure of the polymer and the particles remains unchanged and the overall conductivity of the composite is enhanced by adding particles that are more conductive than the polymer).

Briefly, in accordance with one exemplary embodiment of the invention, a method of manufacturing a component carrier is provided in which a conductive polymer layer is used as a seed layer for subsequent pattern plating, rather than a metal seed layer, as compared to a conventional SAP process. In other words, the metal seed layer may be replaced with a conductive polymer layer. The conductive polymer can be removed ultimately (i.e., after plating of the metal structures forming the fine line structures, e.g., circuit paths) without affecting the metal structures and their traces. As a result, a very fine structure of the circuit path can be generated without affecting the conductor shape and width and without being limited by line and space features.

Fig. 1A to 1G show an exemplary embodiment of a method of manufacturing a component carrier 100 according to the present invention.

Initially, as shown in fig. 1A, a laminate layer is provided having a dielectric material or electrically insulating layer structure 104 (e.g., an ajinomoto laminate film (ABF) layer) and one or more cores of an electrically conductive layer structure 102.

As shown in fig. 1B, the hole 108 is formed in the electrically insulating layer structure 104, for example, by: laser drilling is performed from one main surface of the component carrier, so that in the depicted embodiment a hole defined in the shape of a truncated cone is formed. The holes may extend through the entire thickness of the electrically insulating layer structure 104 and may be bounded at the bottom by the electrically conductive layer structure 102, such as a horizontal pad 106.

Subsequently, as shown in fig. 1C, electrically conductive polymer structures 110 are formed on electrically insulating layer structure 104 and on the tapered sidewalls of apertures 108 and on the exposed upper surface of electrically insulating layer structure 102. In the depicted embodiment, the electrically conductive polymer structure 110 is formed, for example, by sputtering in one process step. Alternatively, although not shown in fig. 1A to 1G, the electrically insulating layer structure may also be formed in two steps, i.e. first forming the electrically conductive polymer structure on the non-porous electrically insulating layer structure, then forming the hole through the (first) electrically conductive polymer structure and in or through the electrically insulating layer structure, and then forming the (second) electrically conductive polymer structure on the side walls and/or the bottom of the hole.

As shown in fig. 1D, a patterned mask of sacrificial material 140 is formed on the electrically conductive polymer structure 110. For example, the dry film may be applied as a patterning mask or a continuous film, followed by exposure and development, thereby patterning the dry film.

Next, as shown in fig. 1E, the metal structure 120 is formed on the electrically conductive polymer structure 110 at the following locations: wherein the electrically conductive polymer structures 110 are exposed from (not covered by) a patterned mask of the sacrificial material 140. The metal structure 120 may particularly be formed by electroplating, and the exposed electrically conductive polymer structure 110 may thus act as a seed layer for the metal plating. The metal structure 120 may fill the hole 108, forming an at least partially tapered metal vertical through connection 122 and a horizontal metal structure 124 thereon.

Subsequently, the patterned mask of sacrificial material 140 may be removed by stripping, as shown in fig. 1F.

As shown in fig. 1G, the electrically conductive polymer structure 110 not covered by the metal structure 120 or exposed from the metal structure 120 may then be removed by dry etching or wet etching, in particular by plasma etching. Thus, the exposed electrically conductive polymer structure 110 and the upper portion 104u of the electrically insulating layer structure 104 are etched, but the metal structure 120 is not etched. As a result, a component carrier 100 is obtained having a common laterally confined layer sequence 130, which common laterally confined layer sequence 130 consists of the metal structure 120, at least part of the electrically conductive polymer structure 110, and the upper portion 104u of the electrically insulating layer structure 104, while the bottom portion 104b of the electrically insulating layer structure 104 protrudes laterally beyond the upper portion 104u of the electrically insulating layer structure 104, which portion forms the laterally confined layer sequence 130.

Although not shown in fig. 1A-1G, the laterally confined layer sequence 130 and the tapered metal vertical through-connection 122, electrically conductive polymer structure 110 and horizontal pad 106 layer sequence may be heat treated to trigger diffusion of metal material into or through electrically conductive polymer structure 110 to improve interconnect reliability. In particular, an interface region comprising a mixture of a metallic material and an electrically conductive polymer material may thereby be formed between the metallic vertical through connection 122 and the horizontal pad 106, which further improves the reliability of the electrical connection.

Fig. 2 shows an enlarged partial view of a component carrier according to an exemplary embodiment of the invention.

Fig. 2 shows two common laterally confined layer sequences 130 consisting of the metal structure 120, the electrically conductive polymer structure 110 and the upper portion 104u of the electrically insulating layer structure 104. Both common laterally confined layer sequences 130 are located on the bottom portion 104b of the electrically insulating layer structure 104.

The common laterally confined layer sequence 130 depicted on the left-hand side of fig. 2 shows an ideal configuration of the common laterally confined layer sequence 130, wherein the metal structure 120, the electrically conductive polymer structure 110 and the upper portion 104u of the electrically insulating layer structure 104 are substantially flush.

However, since the electrically conductive polymer structure 110, (and at least to some extent) the underlying electrically insulating layer structure 104 may be (partially) etched, undercuts may be formed at the electrically conductive polymer structure 110 of the layer sequence 130 and at the upper portion 104u of the electrically insulating layer structure 104, as shown by the common laterally limited layer sequence 130 depicted on the right-hand side of fig. 2, when the electrically conductive polymer structure 110 not covered by the metal structure 120 is removed by dry etching or wet etching, in particular in the case of an isotropic etching technique. However, since the metal structure 120 is not affected by the etching, the layer sequence 130 may not have undercuts at the metal structure 120 also in this case, as further illustrated by the common laterally limited layer sequence 130 depicted on the right-hand side of fig. 2, so that the shape of the conductive tracks or in general the conductors which may ultimately result from the metal structure may be preserved.

It should be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.

The implementation of the invention is not limited to the preferred embodiments shown in the drawings and described above. On the contrary, even in the case of substantially different embodiments, numerous variants are possible which use the solution shown and the principle according to the invention.

Reference numerals

100. Component carrier

102. Electrically conductive layer structure

104. Electrical insulation layer structure

104b bottom portion of the electrically insulating layer structure

104u electrically insulating layer Structure Upper part

106. Pad

108. Hole(s)

110. Electrically conductive polymer structures

120. Metal structure

122. Vertical through connection

124. Horizontal metal structure

130. Layer sequence

140. A sacrificial material.

Claims (28)

1. A component carrier (100), the component carrier (100) comprising:

a stack comprising at least one electrically conductive layer structure (102) and at least one electrically insulating layer structure (104);

an electrically conductive polymer structure (110) located on a portion of the at least one electrically insulating layer structure (104); and

a metal structure (120) on the electrically conductive polymer structure (110);

wherein an upper portion (104 u) of the electrically insulating layer structure (104), at least a portion of the electrically conductive polymer structure (110), and the metal structure (120) form a common laterally confined layer sequence (130).

2. The component carrier (100) according to claim 1, wherein the layer sequence (130) has undercuts at the electrically conductive polymer structure (110).

3. The component carrier (100) according to claim 1 or 2, wherein the layer sequence (130) has an undercut at the upper portion (104 u) of the electrically insulating layer structure (104), for example, the layer sequence (130) has an undercut with a depth of not more than 7 μ ι η at the upper portion (104 u) of the electrically insulating layer structure (104).

4. The component carrier (100) according to claim 1 or 2, wherein the layer sequence (130) has no undercuts at the metal structure (120).

5. The component carrier (100) according to claim 1 or 2, wherein a bottom portion (104 b) of the electrically insulating layer structure (104) protrudes laterally beyond the upper portion (104 u) of the portion of the electrically insulating layer structure (104) forming the laterally confined layer structure (130).

6. The component carrier (100) according to claim 1 or 2, wherein at least one of the at least one electrically conductive layer structure (102) is located below the laterally confined layer sequence (130) and electrically coupled with the laterally confined layer sequence (130).

7. The component carrier (100) of claim 6, wherein the at least one of the at least one electrically-conductive layer structure (102) that is located below the laterally constrained layer sequence (130) and that is electrically coupled with the laterally constrained layer sequence (130) comprises a horizontal pad (106) connected with a vertical through-connection (122).

8. The component carrier (100) according to claim 1 or 2, wherein the electrically conductive polymer structure (110) comprises at least one polymer material selected from: polyfluorene, polyphenyl, polypyrene, polyazulene, polynaphthalene, polyacetylene (PAC), poly (p-phenylene vinylene) (PPV), polypyrrole (PPY), polycarbazole, polyindole, polyaza

Polyaniline (PANI), polythiophene (PT), poly (3, 4-ethylenedioxythiophene) (PEDOT), poly (p-phenylene sulfide) (PPS), polyisothianaphthene (PITN), poly (benzene)And [ c ]]Thiophene), poly (dithiophene 3,2-b:2,3-d thiophene), poly (s-aminophenethiol), poly (o-aminophenol), phthalocyanine-based polymers, bipyridine-based polymers, or mixtures thereof.

9. The component carrier (100) according to claim 1 or 2, wherein the electrically conductive polymer structure (110) comprises at least one polymer material selected from: polyaniline (PANI), poly (3, 4-ethylenedioxythiophene) (PEDOT), poly (p-phenylene sulfide) (PPS), or mixtures thereof.

10. The component carrier (100) according to claim 1 or 2, wherein the electrically conductive polymer structure (110) comprises poly (3, 4-ethylenedioxythiophene) (PEDOT).

11. The component carrier (100) according to claim 1 or 2, wherein the electrically conductive polymer structure (110) comprises a polymer material and metal particles or a doped polymer.

12. The component carrier (100) according to claim 1 or 2, wherein the electrically conductive polymer structure (110) has a thickness of from 0.01 μ ι η to less than 0.4 μ ι η.

13. A method of manufacturing a component carrier (100), wherein the method comprises:

providing a stack comprising at least one electrically conductive layer structure (102) and at least one electrically insulating layer structure (104);

forming an electrically conductive polymer structure (110) on at least one of the at least one electrically insulating layer structure (104); and

forming a metal structure (120) on the electrically conductive polymer structure (110);

wherein an upper portion (104 u) of the electrically insulating layer structure (104), at least a portion of the electrically conductive polymer structure (110), and the metal structure (120) are formed as a common laterally confined layer sequence (130).

14. The method of manufacturing a component carrier (100) according to claim 13, wherein the method further comprises:

forming holes (108) in the stack before and/or after forming the electrically conductive polymer structures.

15. The method of manufacturing a component carrier (100) according to claim 13 or 14, wherein the method comprises forming the electrically conductive polymer structure (110) by sputtering, chemical coating, dispensing a paste, spin coating or printing.

16. The method of manufacturing a component carrier (100) according to claim 13 or 14, wherein the method comprises forming the metal structure (120) by plating or via a conductive paste.

17. The method of manufacturing a component carrier (100) according to claim 13 or 14, wherein the method comprises: after forming the metal structure (120), the electrically conductive polymer structure (110) is removed by dry etching and/or wet etching.

18. The method of manufacturing the component carrier (100) according to claim 17, wherein the dry etch and/or the wet etch for removing the electrically conductive polymer structure (110) is configured to selectively etch the electrically conductive polymer structure (110) but not substantially etch the metal structure (120).

19. Method of manufacturing a component carrier (100) according to claim 13 or 14, wherein the method comprises forming the laterally confined layer sequence (130) using a patterned mask of sacrificial material (140).

20. The method of manufacturing a component carrier (100) according to claim 13 or 14, wherein the method comprises: -heat treating the laterally confined layer sequence (130) to trigger diffusion of a metallic material into or through the electrically conductive polymer structure (110).

21. A component carrier (100), the component carrier (100) comprising:

a stack comprising at least one electrically insulating layer structure (104) and a plurality of electrically conductive layer structures (102) comprising a metal vertical through-connection (122) and a horizontal metal structure (124) on the metal vertical through-connection (122); and

an electrically conductive polymer structure (110), the electrically conductive polymer structure (110) being at least partially located between the at least one electrically insulating layer structure (104) and the horizontal metal structure (124).

22. The component carrier (100) according to claim 21, wherein another part of the electrically conductive polymer structure (110) is located between the at least one electrically insulating layer structure (104) and the metal vertical through-connection (122).

23. The component carrier (100) according to claim 21 or 22, wherein a further portion of the electrically conductive polymer structure (110) is located between the metal vertical through connection (122) and a horizontal pad (106).

24. The component carrier (100) according to claim 21 or 22, wherein an interface region between the metal vertical through-connection (122) and the horizontal pad (106) comprises a mixture of a metal material and an electrically conductive polymer material.

25. The component carrier (100) according to claim 21 or 22, wherein the metal vertical through-connection (122) is an at least partially tapered metal vertical through-connection (122), in particular having a truncated cone shape or having an hourglass shape.

26. A method of manufacturing a component carrier (100), wherein the method comprises:

providing a stack comprising at least one electrically insulating layer structure (104) and a plurality of electrically conductive layer structures (102) comprising a metal vertical through-connection (122) and a horizontal metal structure (124) on the metal vertical through-connection (122); and

forming an electrically conductive polymer structure (110), the electrically conductive polymer structure (110) being located at least partially between the at least one electrically insulating layer structure (104) and the horizontal metal structure (124).

27. The method of manufacturing a component carrier (100) according to claim 26, wherein the method comprises: the metal vertical through-connection (122) is formed by at least one of mechanical drilling and laser drilling or via a photosensitive medium (PID), and subsequent metal plating.

28. The method of manufacturing a component carrier (100) according to claim 26 or 27, wherein the method comprises: an at least partially tapered metal vertical through-connection (122) is formed by laser drilling followed by metal plating.

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