Component carrier with anti-migration structure and method of manufacture

Abstract

A component carrier (100) is described, comprising a stack (101) having at least one electrically insulating layer structure (102) and at least one electrically conductive layer structure (104), and comprising the following features: i) the at least one electrically conductive layer structure (104) comprises a patterned conductive structure (110) disposed on one of the surfaces of the at least one electrically insulating layer structure (102); ii) the patterned conductive structure (110) defines a contact interface (115) between the patterned conductive structure (110) and the surface (103) of the at least one electrically insulating layer structure (102) such that the surface (103) is separated into at least one contact interface portion (120) and at least one free surface portion (130); iii) the property of the metal portion (150) at the at least one free surface portion (130) is such that migration of an electrically conductive material, in particular copper, between adjacent portions of the patterned conductive structure (110) is prevented; and iv) the patterned conductive structure (110) comprises at least one lateral wall (111) defining a lateral edge (112) of the contact interface (115) wherein the lateral wall (111) extends vertically such that, at a contact with the contact interface (115), the lateral wall (111) is at least partially recessed towards a material of the patterned conductive structure (110) relative to an overall vertical extension of the lateral edge (112).

Description

Technical Field

[0001] This disclosure relates to a component carrier having a stack, the stack including at least one electrically insulating layer structure and at least one electrically conductive layer structure. The electrically conductive layer structure includes a patterned conductive structure such that the surface portion of the electrically insulating layer structure is a contact interface portion or a free surface portion. Here, the free surface portion includes a metal portion, which is preferably configured to prevent (copper) migration, and / or portions of the patterned conductive structure may include a specific shape reflecting the manufacturing process. Furthermore, this disclosure relates to a method of manufacturing said component carrier.

[0002] Therefore, this disclosure relates to the technical field of component carriers such as printed circuit boards or IC substrates and their manufacture. Background Technology

[0003] With the increasing functionality of products equipped with component carriers containing one or more electronic components, the miniaturization of such electronic components, and the growing number of electronic components to be mounted on component carriers such as printed circuit boards, there is a growing trend towards more robust array-shaped components or packages with multiple electronic components and numerous contacts or connections with increasingly smaller spacing between them. Removing heat generated by such electronic components and the component carrier itself during operation has become an increasingly important issue. Furthermore, effective protection against electromagnetic interference (EMI) is also becoming increasingly important. Simultaneously, the component carrier must be mechanically robust and electrically and magnetically reliable to operate even under harsh conditions.

[0004] In particular, establishing effective and reliable electrical connections within component carriers may still be considered a challenge. Electrical connections within component carriers are achieved, for example, via metal (typically copper) traces. Within the industry, there is a continuous trend towards smaller structures on one hand, and a continuous trend towards higher signal rates / frequencies on the other. Therefore, the quality and performance of electrical connections within component carriers, such as metal traces, can be critical.

[0005] Conventionally, metal traces can be fabricated using a subtractive process. For example, an electrically conductive layer is placed on a dielectric layer and then patterned by etching. Thus, after etching, the electrically conductive trace remains on top of the dielectric layer. In particular, metal traces can be fabricated using a so-called modified semi-additive process (mSAP). Here, an electrically insulating layer with an (ultra)th thin copper foil (3µm to 5µm) is applied as a raw material. A photoresist is applied by photolithography in areas not covered by the metal trace. The areas not covered by the photoresist are then filled with copper plating to form the trace, after which the photoresist is removed (stripped off). Finally, (fast) etching is performed to remove the thin copper foil.

[0006] Figure 3 A microscopic image of a cross-section through a conventional circuit board 200 is shown. The circuit board 200 includes a dielectric layer 202 and a conductive layer 204 located on top. After patterning the conductive layer 204 by etching, the metal traces 210 of the conductive layer 204 can exhibit, depending on the etching configuration and process settings, as shown... Figure 3 The illustrated elephant-foot shape (wide trace bottom) is shown, wherein the bottom portion of each trace is larger than the corresponding opposite top portion. Furthermore, the contact area 212 between the lateral wall 211 and the dielectric layer surface can have a convex shape and protrude away from the lateral wall 211. Therefore, the vertical extensions of the lateral wall 211 are not straight. It can also be seen that the sidewalls 211 and top of the patterned conductive layer 210 are quite smooth.

[0007] Specific drawbacks of conventional electrical connections can be seen in the electrochemical or ionic migration of the materials used in the connection (in dielectric materials). For example, the metal (especially copper) in a metal trace can be prone to migration, particularly under humid conditions. Due to migration issues, the quality (especially reliability) of the electrical connection can be significantly degraded. In particular, metal traces may suffer from short circuits, especially during long-term operation (e.g., more than a month). A major reason for copper migration may be the combination of a very compact design (small linewidth / spacing ratio) and the amount of current applied. Summary of the Invention

[0008] It may be necessary to prevent the migration of metals (especially copper) in the component carrier in an efficient and reliable manner.

[0009] This article describes a component carrier and its manufacturing method.

[0010] According to one aspect of this disclosure, a component carrier (e.g., a printed circuit board or IC substrate) is described, the component carrier comprising: a (multilayer) stack having at least one electrically insulating layer structure (e.g., a reinforced or unreinforced resin layer) and at least one electrically conductive layer structure (e.g., a metal layer).

[0011] The at least one electrically conductive layer structure includes a patterned conductive structure (particularly a metal trace) disposed on one of the (main) surfaces of the at least one electrically insulating layer structure (the surface being specifically oriented perpendicular to the stacking direction) (preferably, the at least one electrically conductive layer structure and the at least one electrically insulating layer structure may be in direct contact with each other).

[0012] The patterned conductive structure defines a contact interface (e.g., a contact surface) between the patterned conductive structure and the surface of at least one electrically insulating layer structure, such that the surface is divided into at least one contact interface portion (where the surface of the electrically insulating layer structure is covered by a portion of the patterned conductive structure) and at least one free surface portion (where the surface of the electrically insulating layer structure is not (not covered by) a portion of the patterned conductive structure).

[0013] According to one aspect of this disclosure, the properties of the metal portion located at the at least one free surface portion (in particular the amount of metal portion, the distribution of the metal portion, and the type / variety of the metal portion) prevent the migration of an electrically conductive material (metal) between adjacent portions (e.g., metal traces) of the patterned conductive structure, and in particular, the electrically conductive material is copper.

[0014] According to one aspect of this disclosure, the patterned conductive structure includes at least one lateral wall (sidewall) defining a lateral edge of the contact interface (at the contact area), wherein the lateral wall extends vertically (e.g., along Z) such that at the contact portion that contacts the contact interface, the lateral wall is at least partially recessed toward the material of the patterned conductive structure relative to the overall vertical extension of the lateral edge (in other words, a recess is formed in the lateral wall and at the contact interface that contacts the surface of the electrically insulating layer structure; further in other words, the bottom portion (in the vertical direction) of a part of the patterned conductive structure is narrower than the upper portion of said part of the patterned conductive structure).

[0015] According to one aspect of this disclosure, the contact interface includes a metal portion, particularly wherein the metal portion is made of a different material than the material of the patterned conductive structure.

[0016] According to another aspect of this disclosure, a method for manufacturing a component carrier (e.g., as described above) is described, the method comprising: i) Provide at least one electrically insulating layer structure; ii) Arrange at least one electrically conductive layer structure on the (main) surface of the electrically insulating layer structure; iii) Patterning the conductive layer structure to form a patterned conductive structure (e.g., using subtractive processing, SAP process, or mSAP process) so that: The patterned conductive structure defines a contact interface between the patterned conductive structure and the surface of at least one electrically insulating layer structure, such that the surface is divided into at least one contact interface portion and at least one free surface portion. (Specifically, the patterned conductive structure includes at least one lateral wall defining a lateral edge of the contact interface, wherein the lateral wall extends vertically such that: at the contact portion contacting the contact interface, the entire vertical extension of the lateral wall relative to the lateral edge is at least partially recessed toward the material of the patterned conductive structure; and) (iv) (by adjusting the (manufacturing) properties of the metal portion) remove at least a portion of the metal portion located at the at least one free surface portion, thereby preventing the migration of the electrically conductive material between adjacent portions of the patterned conductive structure, in particular, the electrically conductive material is copper.

[0017] Preferably, method steps i) to iv) can be consecutive steps, specifically starting with i), ii) following i), iii) following ii), and iv) following iii).

[0018] In this context, the term "component carrier" can refer to both the final component carrier product and component carrier prefabrications (i.e., component carriers in production, in other words, semi-finished products). In the example, a component carrier prefabrication can be a panel comprising multiple semi-finished component carriers manufactured together. In the final stage, the panel can be separated into multiple final component carrier products.

[0019] In embodiments, the “stack” of the component carrier includes at least one electrically insulating layer structure and at least one electrically conductive layer structure. For example, the component carrier can be a laminate of the aforementioned electrically insulating and electrically conductive layer structures, particularly a laminate formed by applying mechanical pressure and / or heat. The aforementioned stack can provide a plate-like component carrier capable of providing a large mounting surface for other components. In one example, the stack can still be very thin and compact. In another example, for high-density products, the stack can be very thick. The stacking direction (height / thickness) can be arranged along the vertical direction z. Furthermore, the stacking direction can be perpendicular to two directions (along x and y) of the main extension of the (plate-like) component carrier. In one example, all layers of the component carrier can form the stack. In another example, only a portion of the layers of the component carrier forms the stack.

[0020] In this context, the term "layer structure" can specifically refer to continuous or discontinuous layers (or separated islands in the same plane) of electrically conductive or electrically insulating materials. Multiple such layers stacked vertically and parallel to each other can form a stack.

[0021] In this context, the term "patterned conductive structure" can refer to an electrically conductive structure (e.g., a metal, particularly copper, more particularly copper foil; or, for example, carbon, particularly graphene, as a layer) that has been patterned—for example, by subtractive etching, such as wet or plasma etching). After patterning, the electrically conductive structure may, for example, include multiple electrically conductive (metal, such as copper) traces and / or pads and / or interconnects, and / or conductive paths / regions. In this way, electrical connections can be provided within a component carrier.

[0022] In this context, the term "metal portion (located at a free surface portion)" can refer to the presence of a metallic substance (metallic material) at / arranged on the free surface portion of an electrically insulating layer structure (on top of the surface). The presence of a metallic portion at the free surface portion can be significant because the layer structure comprises a dielectric material and the free surface portion (substantially) does not contain the material of the electrically conductive layer structure (patterned conductive structure). The metallic portion can exist as metallic particles / residues, particularly as surface-distributed particles or residues (e.g., resulting in porous layers, discontinuous layers, heterogeneous layers, and in any case, interrupted layers / structures to prevent physical and electrical connections between the two ends of the layer / structure, e.g., physical and electrical connections between adjacent portions of a patterned conductive structure). The metallic portion can differ from the metal of the electrically conductive layer structure, where the metal of the electrically conductive layer structure can primarily comprise copper, while the metallic portion can particularly comprise metals that do not aggravate / intensify / act on (copper) migration. For example, the metallic portion (particles / residues) can include or be composed of chromium. Chromium does not aggravate / intensify / act on copper migration. Alternatively or additionally, the metal portion may include a metal salt, such as a metal oxide. Thus, the metal portion can be in a positively charged state, such as +1 or +2. Optionally, the metal portion may include a shell-like structure, which may be open or closed and is disposed on the outer surface of the metal portion (particle). The shell-like structure may include an electrically insulating material, such as an organic material and / or an inorganic material, where the organic material is (epoxy) resin and the inorganic material is glass. Preferably, the metal portion is located on the surface of the electrically insulating layer structure. In this context, the metal portion (material) should not be construed as part of the electrically insulating layer structure.

[0023] In this context, the term "lateral edge" can refer to the area where the lateral wall of a portion of the patterned conductive structure can contact the contact interface of the (upper main) surface of the electrical insulating layer structure at one (vertical) end and contact the upper portion / surface of the trace at the opposite (vertical) end. In a preferred example, at the lateral edge, a concave extension (towards the material of the portion / part of the patterned conductive structure) may be present in the vertical region above the area where the lateral wall contacts the contact interface. Furthermore or alternatively, the lateral wall may have a convex portion in shape in the area where it is recessed at least partially towards the patterned conductive structure material. In other words, one or more lateral walls may taper towards the surface of the electrical insulating layer structure at the area where the lateral wall is recessed towards the patterned conductive structure material, and preferably, the area above the area where the lateral wall contacts the contact interface tapers away from the surface of the electrical insulating layer structure. This structure can be similar to one of the conventional trace root shapes (see...). Figure 3 In contrast, in the traditional trace root shape, there is a protrusion rather than a concave part at the contact interface (the bottom of the trace), i.e., the "elephant foot" shape.

[0024] In this context, the term "metal portion made of a different material than the material of the patterned conductive structure (and / or electrically conductive layer structure)" can refer to a clear distinction between the metal portion at the contact interface and the material of the patterned conductive structure. In an example, a phase interface may exist between the metal portion and the material of the patterned conductive structure, separating the composition of the metal portion from that of the patterned conductive structure. Preferably, the metal portion may include elements different from one or more elements of the patterned conductive structure, or may be composed of elements different from one or more elements of the patterned conductive structure. Alternatively or additionally, the metal portion may include elements identical to one or more elements of the patterned conductive structure, or may be composed of one or more elements of the patterned conductive structure. Preferably, the crystal structure of the metal portion may differ from the crystal structure of the patterned conductive structure.

[0025] In this context, the term "metal portion" can refer to a portion of metallic material (e.g., chromium) disposed on / on the free surface portion (and / or contact interface portion) of the surface of the electrically insulating layer structure as described above. In contrast, the term "metal migration" can refer to the migration of metal from the electrically conductive layer structure, particularly the patterned conductive structure (e.g., copper). Furthermore, the term "another metallic portion" can refer to a portion of metallic material (e.g., zinc / nickel) located on / on / on the free surface portion and / or contact interface portion that is different from the (described) metallic portion (material). In this context, the metallic portion may have a smaller effect on metal migration compared to the other metallic portion (see above).

[0026] According to exemplary embodiments, this disclosure may be based on the following concept: i) When the properties of the metal portion disposed on the free surface portion of the insulating layer structure—where the insulating layer structure is not covered by a patterned conductive structure (e.g., a metal trace)—are adjusted to prevent the migration of electrically conductive material, and / or ii) When a portion of the patterned conductive structure (especially a trace) has a recess (rather than a protrusion) at the bottom, and / or iii) When the contact interface (located between the patterned conductive structure and the electrically insulating layer structure) includes a metal portion—wherein the metal portion is made of a different material than the material of the patterned conductive structure (particularly copper)— It can efficiently and reliably reduce or even prevent the migration of metals (especially copper) in the component carrier.

[0027] In other words, in a specific example, the space between adjacent portions of a patterned conductive structure (particularly a metal trace) on an insulating layer may include a distribution and / or structure to prevent material migration from the patterned conductive structure (e.g., a copper metal trace). Furthermore, the adjacent portions of the patterned conductive structure may include a specific shape to prevent the migration of electrically conductive material.

[0028] When improving the quality and performance of component carriers, the migration of metals and metal-containing materials (i.e., metal ions) in electrically conductive layer structures, especially patterned conductive structures, can be considered an important problem to be solved. However, the process of metal migration is not well understood, and improving component carriers in this regard may be considered a challenge.

[0029] The present discloser has now unexpectedly discovered that the manufacturing conditions of the component carrier can be adjusted such that the distribution and / or structure of the metal portion prevents material migration from the patterned (metallic) conductive structure located on the insulating layer structure and prevents electrical conduction between adjacent portions of the patterned conductive structure. For example, the metal portion can be a residue retained after patterning, for example, by flash etching. Such metal residues can be very small (the corresponding metal (porous) layer can be very thin). In many cases, the metal portion may only be detectable using a high-resolution electron microscope, such as a transmission electron microscope.

[0030] Metallic material portions can often be so small / thin that they are no longer considered. However, the present discloser has unexpectedly discovered that said metallic portions located at free surface portions can have a significant influence on metal (particularly copper) migration. Therefore, depending on the nature of the metallic portion (e.g., type, amount, distribution), migration can be reduced, prevented, or promoted. In a specific example, it has been found that chromium located at free surface portions (as particles and / or as layers) does not exacerbate / intensify / act on copper migration between metal traces. In another specific example, it has been found that zinc / nickel located at free surface portions (as particles and / or as layers) promotes copper migration between metal traces.

[0031] Based on the understanding that (copper) migration can occur along extremely thin metal structures (e.g., made of particles, residues) between adjacent portions of a patterned conductive structure, it has been found that migration, particularly with respect to ultrathin metal structures, can be further prevented by increasing the distance between said adjacent portions. A particularly effective way to achieve this advantage is to form recesses at the contact area between the lateral walls of a portion of the patterned conductive structure and the contact interface of the insulating layer structure.

[0032] The described metal section configuration can further provide additional heat transfer capabilities (i.e., efficient temperature management within the stack / component carrier).

[0033] According to the described method, using a well-regulated manufacturing process, (copper) migration can be prevented in an efficient and reliable manner. The described method can be implemented directly in existing component carrier manufacturing processes, such as etching.

[0034] Exemplary Implementation In this implementation, the at least one free surface portion is (substantially) free of metal. Even if a metal portion (i.e., in the form of a layer / structure) is provided / required between the electrically conductive layer structure and the corresponding electrically insulating layer structure (and then generated at the contact interface after the electrically conductive layer structure is patterned), no such metal residue remains in that portion because processing is performed at the portion corresponding to the at least one free surface portion on the surface of the electrically insulating layer portion. This can have the advantage of minimizing the chance of migration events, since only insulating material, such as an electrically insulating layer structure or gas, may be present between two adjacent patterned conductive structures (in the main extension direction of the stack).

[0035] In this embodiment, the properties of the metal portion include at least one of the amount of metal portion, the type of metal portion, and the distribution of the metal portion. These properties can be adjusted depending on the desired application; in particular, they can be adjusted by adjusting the process parameters used in manufacturing.

[0036] The term "amount" can refer to the volume and / or concentration of the metal portion at the free surface portion. Alternatively, amount can refer to the metal load located at the free surface portion, such as the mass or volume per free surface portion. In one example, a low amount can be intentionally maintained to prevent migration. In another example, the amount of a first metal (particularly a metal that prevents migration, such as chromium) can be increased while the amount of a second metal (particularly a metal that promotes migration, such as zinc / nickel) can be decreased.

[0037] The term "type" can refer to the type of metal, such as the corresponding chemical element. Therefore, the types of metals can include copper, iron, tungsten, tin, etc. Furthermore, the term "type" can refer to chemical composition, such as the phases present in the metal. Other (physical / chemical) properties of the metal can also be considered. In the examples, type can include different modifications or crystal structures of the metal. In various examples, type can include (macroscopic) shapes, such as cubic, spherical, or needle-like shapes.

[0038] The term "distribution" can refer to the overall location of metal, such as the location of particles, residues, or other metallic structures. For example, Figure 5 shows examples of the distribution of different types of metals on the surface of an electrically insulating layer structure. In the examples, there may be contact interfaces, particularly portions of free surface areas, that are (completely) covered by metal portions. In different examples, there may be contact interfaces, particularly portions of free surface areas, that are either devoid of metal or have a low amount of metal associated with the corresponding surface portions.

[0039] Depending on the combination of the quantity, type, and distribution of the metal particles, migration can be influenced, and in particular prevented. Advantageous properties in this regard could be, for example, a higher quantity of chromium particles and a lower quantity of zinc / nickel particles. Migration can be further prevented if the distribution is chosen such that the particles (essentially) do not come into direct contact.

[0040] In one embodiment, the amount of metal on at least one free surface portion (and / or the particles / residues of the metal portion are spaced apart from each other) causes the resistance generated between adjacent portions of the patterned conductive structure to prevent electrical conduction between said adjacent portions of the patterned conductive structure.

[0041] In embodiments, the metal portion exists in the form of at least one of particles, residues, or layers. The metal portion exists as surface-distributed particles / residues, thereby forming a porous layer, and / or a discontinuous layer, a heterogeneous layer. In cases where the metal portion on the free surface portion is an interrupted layer / structure, physical and electrical connections between the two ends of the layer / structure are prevented, particularly physical and electrical connections between two adjacent portions of a patterned conductive structure. This can reflect a manufacturing process in which the metal portion is retained after a subtractive process such as etching. In other words, the metal portion is equivalent to a residue from a previous layer, such as an electrically conductive layer structure (before patterning), located on the free surface portion. In an example, the metal portion may include or be composed of material from or made of the electrically conductive layer structure. In another example, the metal portion may include or be composed of material from or made of a chemical solution from a manufacturing process (e.g., an etching process). This can provide the advantage that the migration of metal and / or material can be further prevented because the free metal portion can affect the migration ability of the metal or material.

[0042] In one example, the metal parts can exist as individual particles that are (at least partially) interconnected. In another example, the metal parts can exist as layers, particularly porous layers. In yet another example, the metal parts can exist as continuous or discontinuous (e.g., separated islands) layered structures. In yet another example, the metal parts can exist as planar or non-planar layered structures.

[0043] In this embodiment, the metal portion forms a metal structure. As described above, the metal portion can exist as individual particles / residues or as a (porous / heterogeneous) layer structure. The metal portion can also be formed as interconnected particles / residues forming a metal structure, for example, as a (thin, particularly ultrathin) structure. For example, it can be... Figure 5AAs seen in the diagram, the metallic structure can reflect (follow) the rough surface of the electrical insulation layer structure and includes multiple corrugated sections, edges, or corners. This can provide the advantage of reduced migration in the spatial direction, as the metallic structure follows the contours of adjacent electrical insulation layer structures.

[0044] In this embodiment, the metal structure is non-planar. The surface distribution of the metal structure corresponds to the roughness of the free surface portion of the electrical insulating layer structure. In the example, the roughness of the metal structure in the free surface portion ranges from 1 nm to 10 μm. Therefore, the metal structure can be formed directly on top of the electrical insulating layer structure and follows the shape of the peaks and valleys of the electrical insulating layer structure. This provides the advantage of a stable metal / dielectric connection. In many applications, the dielectric layer surface is roughened to improve adhesion to the metal layer.

[0045] In this implementation, the thickness of the metal (layer) structure ranges from 10 nm to 150 nm. This provides the advantage that an extremely thin (ultra-thin) metal structure is provided, yet it still effectively reduces / prevents migration. Because the structure can be so thin, its impact on the component's load-bearing function and / or overall thickness is negligible.

[0046] In this embodiment, the particles of the metal portion are distributed and / or connected to each other to form a discontinuous, particularly heterogeneous structure. This structure can reflect a manufacturing step (e.g., etching) that removes electrically conductive material from the free surface portion. Unlike a continuous layer (e.g., an initial electrically conductive layer structure), the metal portion can include multiple particles / residues that can be distributed in a fairly random manner, forming a partially connected particle structure. This discontinuous / heterogeneous distribution of the particles further prevents (copper) migration because there is no direct interconnection between (all) the particles.

[0047] In this implementation, the particles / residues of the metal portion are arranged in a spaced-apart manner, such that the resistance generated between adjacent portions of the patterned conductive structure prevents electrical conduction between said adjacent portions. This can further provide the advantage of reliably creating electrically conductive traces spaced apart from each other, for example, by a distance of 1 μm or more, because short circuits can be eliminated.

[0048] In this implementation, the sidewalls of the patterned conductive structure have vertical, straight extensions (z) above the contact portion that contacts the contact interface. This uniformity of the sidewalls improves signal transmission. Furthermore, this structure can further support and prevent migration. The (substantially) straight sidewalls can further reflect the manufacturing process, such as (rapid) etching.

[0049] In one embodiment, the sidewalls of the patterned conductive structure have tapered extensions in the region above the contact portion that contacts the contact interface. Specifically, the tapered extensions taper in a direction oriented away from the surface of the at least one electrically insulating layer structure. This tapering at the top portion can reflect manufacturing steps, such as the etch subtraction steps used to create the patterned conductive structure. This offers the advantage of reliably patterning the electrically conductive layer structure while reducing the likelihood of metal migration.

[0050] In an implementation, the taper at the bottom portion of the patterned conductive structure and the taper at the top portion of the patterned conductive structure can be symmetrical. Similarly, the taper around the bottom portion and / or the top portion can be symmetrical. Additionally, this feature can reflect manufacturing steps, such as a two-step subtractive etching step. This can further reduce migration due to the symmetrical shape.

[0051] In one embodiment, the side walls of the patterned conductive structure (part / section) have concave vertical extensions in the region above the contact portion that contacts the contact interface. Specifically, the concave vertical extensions are concave towards the patterned conductive structure material. Depending on the manufacturing process, the side edges may include not only recesses but also concave-shaped portions. Furthermore, the recesses may include portions with convex shapes. This allows for even more efficient prevention of migration. Dielectric materials, such as resins from other electrically insulating layer structures, can infiltrate / flow into the concave-shaped portions, thereby increasing stability.

[0052] In this embodiment, the roughness of the sidewalls and the roughness of the patterned conductive structure at the contact interface are within a comparable, particularly similar, numerical range. A comparable, particularly similar, roughness range means that the deviation of the average roughness value (i.e., Ra value) is no greater than 10%, preferably no more than 5%. This characteristic indicates that the two roughened surfaces have been created in the same process step, particularly during the etching process that roughens the surfaces. Roughened metal surfaces can increase adhesion to the corresponding dielectric layer.

[0053] In one embodiment, the component carrier further includes an additional electrically insulating layer structure that contacts the at least one free surface portion (and the patterned conductive structure) to form a dielectric contact surface, wherein a metal portion is at least partially disposed at the dielectric contact surface. This can provide the advantage of providing multilayer stacks in an efficient and stable manner. The metal portion at the interface (dielectric contact surface) between the electrically insulating layer structures can enhance connection stability. In the example, the metal portion is (at least partially) embedded (partially enclosed) in the dielectric material of the electrically insulating layer structure.

[0054] In this implementation, the patterned conductive structure is embedded (enclosed) within the dielectric material of the electrically insulating layer structure. This increases the robustness (and protection) of the electrical connection.

[0055] In this embodiment, the metal portion is at least partially disposed between the electrically insulating layer structure and another electrically insulating layer structure. In this embodiment, the electrically insulating layer structure and the other electrically insulating layer structure are in direct contact with the metal portion. In other words, the metal portion (metal structure) can be sandwiched between the electrically insulating layer structures. Therefore, the metal portion is well protected, while improving the overall performance of the component carrier.

[0056] In this embodiment, the metal portion (at the free surface portion) is at least partially arranged (partially sandwiched) between an electrically insulating layer structure and another electrically insulating layer structure. This provides the advantage of increased stability of the component carrier. Furthermore, migration can be further prevented when the metal portion is encapsulated in a dielectric material.

[0057] In this embodiment, at least a portion of the contact area of ​​the contact interface, recessed towards the patterned conductive structure, is in direct contact with an additional electrically insulating layer structure. This can provide the advantage of increased stability of the component carrier. Furthermore, migration can be further prevented when the material of the patterned conductive structure is encapsulated in a dielectric material.

[0058] In this implementation, at least one portion of the patterned conductive structure includes electrically conductive traces, particularly adjacent electrically conductive traces. Therefore, the described method can be directly applied to economically important electrical connections. Such traces can be arranged adjacent to each other, for example, (at least partially) parallel to each other.

[0059] Preferably, the term "adjacent" refers to a (planar) distance of at least 1 μm, more preferably at least 2 μm, and more preferably at least 5 μm between two portions. This provides the advantage that high-quality conductive traces can be formed, wherein migration between conductive traces is reduced / prevented (and therefore there is no performance degradation between conductive traces).

[0060] In one embodiment, at least one portion of the patterned conductive structure includes at least one pad / protrusion, particularly wherein the at least one pad / protrusion is adjacent to another portion of the patterned conductive structure, the other portion specifically including at least one electrically conductive trace. Thus, efficient and robust electrical connections conforming to proven methods can be directly applied, thereby simultaneously ensuring prevention of metal migration and electrical conduction between two adjacent portions (pad-trace) of the patterned conductive layer structure.

[0061] In an embodiment, the patterned conductive structure includes at least one additional electrically conductive (layer) structure, specifically, this additional electrically conductive (layer) structure is made of a different material (e.g., zinc and / or nickel) than the material of the patterned conductive structure. This additional electrically conductive (layer) structure can provide surface properties to the patterned conductive structure, such as adhesion to one of the electrically insulating layer structures, or protection against external chemical compositions / environments. In an embodiment, the additional layer structure is in contact with the electrically insulating layer structure and / or another electrically insulating layer structure. The additional electrically conductive layer structure can define the interaction between one or both of the electrically insulating layer structure and the electrically conductive layer structure.

[0062] In an embodiment, an additional electrically conductive layer structure is disposed at the contact interface between the surfaces of the patterned conductive structure and the electrically insulating layer structure. Preferably, the additional electrically conductive layer structure is in the form of a layer and / or a layer structure (e.g., having a thickness between 5 nm and 100 nm). Preferably, the additional electrically conductive layer structure is made of a material comprising at least one (chemical) component identical to one of the metal portions located on the free surface portion; more preferably, the amount per unit volume of the chemical component common to one of the metal portions in the additional electrically conductive layer structure is greater than the amount per unit volume of the component in the metal portion (located on at least one free surface portion of the electrically insulating layer structure), and more preferably, the amount is greater than at least 30%, particularly greater than 50%, of the amount of the component in the metal portion. Chemical component refers to the type of metal itself, and / or the type of metal component contained in the composition of the additional electrically conductive layer structure, and / or the type of metal located on at least the free surface portion.

[0063] This is a trace of the fact that even when a metal layer / metal structure is provided / required between an electrically conductive layer structure and a corresponding electrically insulating layer structure (e.g., for adhesion reasons), due to the treatment at the portion corresponding to at least one free surface portion of the surface of the electrically insulating layer portion, some metal remains (which then have the same chemical composition as the other electrically insulating layer), but has the property of preventing the electrically conductive material from migrating between adjacent portions of the patterned conductive structure (resulting in a discontinuity-disruption of the resulting metal layer-structure).

[0064] In this embodiment, the metal portion comprises a material different from the material of the electrically conductive layer structure (e.g., copper). For example, the metal portion (or another metal portion) may include at least one of chromium, nickel, zinc, titanium, manganese, tungsten, iron, and tin. Preferably, the manufacturing conditions may be adjusted such that the properties of the metal portion prevent rather than promote migration.

[0065] In this embodiment, the contact area (recess) where the lateral wall contacts the contact interface is (substantially) free of metal (preferably filled with a dielectric material). Thus, the material of the patterned conductive structure can be protected and physically shielded against migration.

[0066] In an embodiment, the surface of the at least one electrically insulating layer structure includes an irregular shape; in particular, the surface of the at least one electrically insulating layer structure includes roughness; more specifically, the surface of the at least one electrically insulating layer structure includes at least one of edges, corners, and corrugations (in other words, any structure that is not planar / flat in a plane). This can provide the advantage of ensuring good adhesion between the at least one electrically insulating layer structure and the at least one other electrically insulating layer structure or patterned conductive structure because the surface area is increased compared to a flat structure.

[0067] In one embodiment, the metal portion comprises aggregates of at least two particles, and more particularly, the metal portion comprises aggregates of at least four particles. These aggregates can be spatially separated from each other, thereby inhibiting the migration path of electrically conductive materials such as copper due to the interruption between the individual aggregates.

[0068] In implementations, patterning includes etching, particularly wet or plasma etching, and more particularly, flash etching. This provides the advantage of being able to directly apply pre-formed subtractive processes (especially semi-additive processes (SAP) or modified semi-additive processes (mSAP)). Furthermore, the applied additives (e.g., for flash etching) can promote the formation of the metal portion. Thus, the metal portion can be formed in a planned manner. In examples, flash etching can use H2O2 and / or H2SO4, along with one or more additives. Such additives can include rheology modifiers, surfactants, inhibitors, leveling agents, accelerators, brighteners, etc.

[0069] In one embodiment, at least a portion of the metal portion is removed by adjusting the process parameters (used for manufacturing). In another embodiment, the method specifically includes adjusting the process parameters such that the properties of the metal portion located at at least one free surface portion prevent the migration of electrically conductive material—particularly copper—between adjacent portions of the patterned conductive structure. In yet another embodiment, the method further includes adjusting the process parameters such that the metal portion comprises or is composed of a metal—particularly chromium—that does not (substantially) aggravate / exacerbate / act on the migration of the electrically conductive material. In this way, the manufacturing process can be designed so that the migration problem can be overcome efficiently.

[0070] Adjustable process parameters may include: - Provide process parameters for one or more nozzles of the etching solution. - Process parameters for etching rate (e.g., 8.6 μm per pass through the flash etching line). - The chemical composition of the etching solution, especially the additives in the etching solution. Preferably, appropriate parameters (e.g., etching settings) can be selected to achieve the desired properties and minimize the risk of electrochemical migration.

[0071] In a specific example, the metallic portion may (at least partially) be a residue from the anti-discoloration / adhesion-promoting layer of the (ultra-thin) copper foil (mSAP process). The copper foil is typically removed by (rapid) etching. However, depending on the adjustment of process parameters, this layer of (metallic) residue can prevent or promote migration.

[0072] In one example, the metal parts may exist as individual particles that may be (at least partially) interconnected. In another example, the metal parts are formed as a continuous or discontinuous (e.g., separated islands) layered structure. In yet another example, the metal parts are arranged in the form of a planar or non-planar layered structure.

[0073] In this implementation, the patterned conductive structure is embedded (encapsulated) within the dielectric material of the electrically insulating layer structure. This improves the robustness (and protection) of the electrical connection.

[0074] In this embodiment, the electrically insulating layer structure and other electrically insulating layer structures are in direct contact with the metal portion. In other words, the metal portion (structure) can be sandwiched (arranged) between the electrically insulating layer structures. This provides good protection for the metal portion (e.g., preventing eventual oxidation) while improving the overall performance of the component carrier.

[0075] In this implementation, the metal portion comprises or is composed of chromium. It has been unexpectedly found that chromium (especially in appropriate amounts) does not exacerbate or aggravate the migration of material acting on the patterned conductive structure; furthermore, chromium has been identified as having good adhesive properties. Therefore, process parameters can be selected to make the amount of chromium in the metal portion (structure) particularly high. In the example, the chromium content can be (very) low and / or the chromium can be encapsulated or isolated by a (dielectric) polymer matrix, such that the resistance of the dielectric layer supports and prevents migration.

[0076] In this embodiment, the thickness of the chromium layer is in the range of 10 nm to 150 nm. This allows for particularly efficient prevention of migration while having almost no impact on the overall thickness of the stack.

[0077] In this implementation, the amount of anti-migration metal portion per unit area—particularly including chromium or metal portion made of chromium—is greater than the amount of other types of additional metal portions (materials)—such as nickel or zinc. Specifically, the amount of anti-migration metal portion per unit area—particularly including chromium or metal portion made of chromium—is two times or more than the amount of other types of additional metal portions (materials)—such as nickel or zinc. More specifically, the amount of anti-migration metal portion per unit area—particularly including chromium or metal portion made of chromium—is five times or more than the amount of other types of additional metal portions (materials)—such as nickel or zinc. Even more specifically, the amount of anti-migration metal portion per unit area—particularly including chromium or metal portion made of chromium—is ten times or more than the amount of other types of additional metal portions (materials)—such as nickel or zinc. Because a larger amount of metal portion (compared to other migration-promoting metal portions) is less likely to promote or aggravate / intensify / act on metal migration, migration—particularly the migration of materials in the electrically conductive layer structure—can be efficiently reduced.

[0078] In this embodiment, at least two different types of metal portions are provided on the free contact portion; in particular, a metal portion and an additional metal portion are provided on the free contact portion. This provides the advantage of preventing migration, particularly copper migration, through the metal portions, and the advantage of ensuring reliable bonding between adjacent layers having a contact interface through the adhesive-promoting properties of the additional metal portions.

[0079] In an embodiment, an additional metal portion—particularly zinc and / or nickel—is adjacent to a metal portion—particularly including chromium or a metal portion made of chromium.

[0080] In the embodiments, metal portions and / or additional metal portions are arranged on the surface of the electrical insulation layer structure, and in particular, metal portions and / or additional metal portions are arranged on the free surface portion and / or the contact interface portion.

[0081] For example, as can be seen in Figure 5, different chemical elements (metals) can follow different distribution patterns. To achieve favorable performance, the manufacturing process can be appropriately modified.

[0082] In embodiments, the nature of the metal portion at the at least one free surface portion prevents the migration of electrically conductive material—particularly copper—between adjacent portions of the patterned conductive structure, or the metal portion does not facilitate metal migration, and / or the patterned conductive structure includes at least one lateral wall defining a lateral edge of the contact interface, wherein the lateral wall extends vertically such that at the contact portion contacting the contact interface, the entire vertical extension of the lateral wall relative to the lateral edge is at least partially recessed toward the material of the patterned conductive structure (see, for example...). Figure 2 This architecture of patterned conductive structures (e.g., fabricated using specific (fast) etching schemes) can further reduce / prevent the migration of patterned conductive structure material.

[0083] In one embodiment, the amount of metal on the at least one free surface portion causes the resistance generated between adjacent portions of the patterned conductive structure to prevent electrical conduction between the adjacent portions of the patterned conductive structure.

[0084] In one embodiment, the particles / residues of the metal portion are arranged in a spaced-apart manner, such that the resistance generated between adjacent portions of the patterned conductive structure prevents electrical conduction between the adjacent portions of the patterned conductive structure.

[0085] This can further provide the following advantages: reliably creating electrical conduction traces that are spaced apart from each other, for example, by a distance of 1 μm or more, because short circuits can be eliminated.

[0086] In this implementation, the electrical insulation layer structure includes an inorganic layer structure (e.g., a glass (core) layer). This can increase stability and / or allow for the direct application of economically important materials.

[0087] In this embodiment, the electrical conductivity of the metal portion is lower than that of the material of the patterned electrically conductive structure—such as copper (but approximately the conductivity of chromium)—making the metal portion different from the metal of the electrically conductive structure. For example, the metal portion may have a conductivity less than 2 × 10⁻⁶. 7 The conductivity of S / m (e.g., zinc, nickel) is preferably less than 9 × 10⁻⁶. 6 The conductivity of S / m (chromium) is preferably less than 1000 S / m. In particular, the difference between the conductivity of the material of the conductive layer structure / trace and the conductivity of the material of the metal part is greater than 300%. This ensures that the migration of materials, especially metals, is prevented.

[0088] In embodiments, the metal portion (structure) may also include sulfur and / or phosphorus. While phosphorus is common in resin materials (e.g., FR4) (see...) Figure 5GHowever, sulfur may actually be a contaminant. These elements can prevent migration problems or affect the migration behavior of metals in the conductive layer structure, so their presence at the metal site may be beneficial.

[0089] In this implementation, the component carrier is shaped as a plate. This contributes to a compact design, where the component carrier still provides a large base for mounting components. Furthermore, bare wafers, particularly as examples of embedded electronic components—due to their small thickness—can be conveniently embedded in thin plates such as printed circuit boards.

[0090] In one embodiment, the component carrier is configured as one of a printed circuit board, a substrate (particularly an IC substrate), and an interposer.

[0091] In the context of this application, the term "printed circuit board" (PCB) can specifically refer to a plate-shaped component carrier formed by laminating multiple electrically conductive layer structures with multiple electrically insulating layer structures (e.g., by applying pressure and / or by supplying heat). As preferred materials for PCB technology, the electrically conductive layer structures are made of copper, while the electrically insulating layer structures may include resin and / or glass fiber, i.e., so-called prepreg or FR4 material. The individual electrically conductive layer structures can be connected to each other in a desired manner by forming holes through the laminate (e.g., by laser drilling or mechanical drilling) and by partially or completely filling these holes with an electrically conductive material (particularly copper), thereby forming vias or any other through-hole connections. The filled holes either connect the entire stack (through-hole connections extending through multiple layers or the entire stack) or connect at least two electrically conductive layers, referred to as vias. Similarly, optical interconnects can be formed through the individual layers of the stack to accommodate electro-optical circuit boards (EOCBs). In addition to one or more components that can be embedded within a printed circuit board, printed circuit boards are typically configured to house one or more components on one or two opposite surfaces of a board-shaped printed circuit board. They can be soldered to the respective main surfaces. The dielectric portions of the PCB may consist of resin with reinforcing fibers, such as glass fiber.

[0092] In the context of this application, the term "substrate" can specifically refer to a small component carrier. Compared to a PCB, a substrate can be a relatively small component carrier on which one or more components can be mounted, and which can serve as a connection medium between one or more chips and another PCB. For example, a substrate can have substantially the same size as the components (especially electronic components) to be mounted thereon (e.g., in the case of chip-scale packaging (CSP)). More specifically, a substrate can be understood as a carrier for electrical connections or electrical grids and a component carrier similar to a printed circuit board (PCB), but with a higher density of lateral and / or vertically arranged connections. Lateral connections are, for example, conductive paths, while vertical connections can be, for example, drilled holes. These lateral and / or vertical connections are arranged within the substrate and can be used to provide electrical, thermal, and / or mechanical connections between packaged or unpackaged components (e.g., bare wafers), especially IC chips, and printed circuit boards or intermediate printed circuit boards. Therefore, the term "substrate" also includes "IC substrate". The dielectric portion of the substrate can be composed of resin with reinforcing particles (e.g., reinforcing spheres, particularly glass spheres).

[0093] In the context of this application, the term "inorganic layer structure" may specifically refer to a layer structure comprising inorganic materials (e.g., inorganic compounds). In particular, the dielectric material of the inorganic layer structure, or even the entire inorganic layer structure, may be made of only or at least substantially only inorganic materials. In another embodiment, the inorganic layer structure may include inorganic dielectric materials and additional dielectric materials. The inorganic compound may be a compound lacking carbon-hydrogen bonds or a compound that is not an organic compound. In one example, the inorganic layer structure may include glass, such as silicon-based glass, particularly soda-lime glass and / or borosilicate glass and / or aluminosilicate glass and / or lithium silicate glass and / or non-alkaline glass. In another example, the inorganic layer structure may include ceramic materials, such as aluminum nitride and / or alumina and / or silicon nitride and / or boron nitride and / or tungsten-containing ceramic materials. In yet another example, the inorganic layer structure may include semiconductor materials, such as silicon and / or germanium and / or silicon oxide and / or germanium oxide and / or silicon carbide and / or gallium nitride. In another embodiment, the inorganic layer structure may include (elemental) metals and / or metal alloys, such as copper and / or tin and / or bronze. In yet another embodiment, the inorganic layer structure may include inorganic materials not listed in the above examples, such as: MoS2, CuGaO2, AgAlO2, LiGaTe2, AgInSe2, CuFeS2, BeO.

[0094] The substrate or interlayer may include or consist of at least one layer of glass, silicon (Si), and / or photo-imageable or dry-etchable organic material such as epoxy-based laminated material (e.g., epoxy-based laminated film), or polymeric composite (which may or may not include photosensitive and / or thermosensitive molecules) such as polyimide or polybenzoxazole.

[0095] In embodiments, the at least one electrically insulating layer structure (and / or curable dielectric element) comprises at least one of the following: resins or polymers, such as epoxy resins, cyanate ester resins, benzocyclobutene resins, bismaleimide-triazine resins, polyphenylene derivatives (e.g., polyphenylene ether-based, PPE), polyimide (PI), polyamide (PA), liquid crystal polymers (LCP), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and / or combinations thereof. Reinforcing structures, such as webs, fibers, spheres, or other types of filler particles, made of glass (multilayer glass), may also be used to form a composite. The semi-cured resin combined with a reinforcing agent (e.g., fibers impregnated with the aforementioned resins) is called a prepreg. These prepregs are typically named for their properties, such as FR4 or FR5, which describe their flame-retardant properties. While prepregs, particularly FR4, are generally preferred for rigid PCBs, other materials may also be used, particularly epoxy-based stacking materials (e.g., stacked films) or photo-imageable dielectric materials. For high-frequency applications, high-frequency materials such as polytetrafluoroethylene, liquid crystal polymers, and / or cyanate resins are preferred. In addition to these polymers, low-temperature co-fired ceramics (LTCC) or other low, very low, or ultra-low DK materials can be used as electrical insulation structures in component carriers.

[0096] In an embodiment, the at least one electrically conductive layer structure comprises at least one of the following: copper, aluminum, nickel, silver, gold, palladium, tungsten, carbon, platinum, (doped) silicon, and magnesium. While copper is generally preferred, other materials or coated versions thereof are also possible, particularly those coated with superconducting materials or conductive polymers, such as graphene or poly(3,4-ethylenedioxythiophene) (PEDOT).

[0097] At least one component may be embedded in and / or surface-mounted on a component carrier. Such a component may be selected from the following: non-electrically conductive inlays, electrically conductive inlays (e.g., metallic inlays, preferably copper or aluminum), heat transfer units (e.g., heat pipes), optical guiding elements (e.g., optical waveguides or optical conductor connectors), electronic components, or combinations thereof. The inlay may be, for example, a metal block with or without an insulating material coating (IMS-inlay), which may be embedded or surface-mounted to facilitate heat dissipation. Suitable materials are defined by their thermal conductivity, which should be at least 2 W / mK. These materials are typically based on, but not limited to, metals, metal oxides, and / or ceramics, such as copper, alumina (Al₂O₃), or aluminum nitride (AlN). Other geometries with increased surface area are also frequently used to improve heat exchange capacity. In addition, components can be active electronic components (implemented with at least one pn junction), passive electronic components such as resistors, inductors, or capacitors, electronic chips, storage devices (e.g., DRAM or other data memories), filters, integrated circuits (e.g., field-programmable gate arrays (FPGAs), programmable array logic (PALs), general-purpose array logic (GALs), and complex programmable logic devices (CPLDs)), signal processing components, power management components (e.g., field-effect transistors (FETs), metal-oxide-semiconductor field-effect transistors (MOSFETs), complementary metal-oxide-semiconductor (CMOS) transistors, junction field-effect transistors (JFETs), or insulated transistors). Infinity-gate field-effect transistors (IGFETs), all based on semiconductor materials such as silicon carbide (SiC), gallium arsenide (GaAs), gallium nitride (GaN), gallium oxide (Ga2O3), indium gallium arsenide (InGaAs), and / or any other suitable inorganic compound, include optoelectronic interface elements, light-emitting diodes, optocouplers, voltage converters (e.g., DC / DC converters or AC / DC converters), cryptographic components, transmitters and / or receivers, electromechanical transducers, sensors, actuators, microelectromechanical systems (MEMS), microprocessors, capacitors, resistors, inductors, batteries, switches, cameras, antennas, logic chips, and energy harvesting units. However, other components can be embedded within component carriers. For example, magnetic elements can be used as components. Such magnetic elements can be permanent magnetic elements (e.g., ferromagnetic, antiferromagnetic, multiferroic, or ferrimagnetic elements, such as ferrite cores) or paramagnetic elements. However, components can also be IC substrates, interposers, or other component carriers, such as in a board-in-board configuration. Components may be surface-mounted on a component carrier and / or embedded therein. Additionally, other components may be used, particularly those that generate and emit electromagnetic radiation and / or are sensitive to electromagnetic radiation propagating from the environment.

[0098] In one embodiment, the component carrier is a laminated component carrier. In this embodiment, the component carrier is a multilayer composite structure that is stacked and connected together by applying pressure and / or heat.

[0099] After processing the internal layer structure of the component carrier, one or two opposite main surfaces of the processed layer structure can be symmetrically or asymmetrically covered with one or more additional electrically insulating and / or electrically conductive layer structures (particularly by lamination). In other words, stacking can continue until the desired number of layers is obtained.

[0100] After the stacked components of the electrical insulation layer structure and the electrical conductivity layer structure are formed, the obtained layer structure or component carrier can be surface treated.

[0101] In particular, regarding surface treatment, an electrically insulating solder resist can be applied to one or two opposite main surfaces of the laminate or component carrier. For example, such a solder resist can be formed across the entire main surface, and the solder resist layer can then be patterned to expose one or more electrically conductive surface portions that will be used to electrically connect the component carrier to electronic peripherals. The surfaces of the component carrier that remain covered by the solder resist (especially copper-containing surfaces) can be effectively protected against oxidation or corrosion.

[0102] In terms of surface treatment, surface treatment can also be selectively applied to the exposed electrically conductive surface portions of the component carrier. Such surface treatment can be an electrically conductive covering material on the exposed electrically conductive layer structure (e.g., pads, conductive traces, etc., particularly including or composed of copper) on the surface of the component carrier. If such exposed electrically conductive layer structure is not protected, the exposed electrically conductive component carrier material (especially copper) may oxidize, reducing the reliability of the component carrier.

[0103] The surface-treated section can then be formed, for example, as a joint between a surface-mount component and a component carrier. The surface-treated section protects the exposed conductive layer structure (particularly copper circuitry) and enables bonding processes with one or more components (e.g., by soldering). Examples of suitable materials for the surface-treated section include organic solderable corrosion inhibitors (OSP), electroless nickel immersion gold (ENIG), electroless nickel immersion palladium immersion gold (ENIPIG), gold (particularly hard gold), electroless tin, nickel-gold, nickel-palladium, etc. Attached Figure Description

[0104] The foregoing limitations and other aspects of this disclosure will become apparent from the examples of embodiments described below, and will be described with reference to these examples of embodiments.

[0105] Figure 1A cross-section through a component carrier according to an exemplary embodiment of the present disclosure is shown.

[0106] Figure 2 A microscopic image is shown through a cross section of a component carrier according to an exemplary embodiment of the present disclosure.

[0107] Figure 3 A microscopic image of a cross-section through a conventional circuit board is shown.

[0108] Figure 4A A top view of a conventional circuit board is shown, while Figure 4B A top view of a component carrier according to an exemplary embodiment of the present disclosure is shown.

[0109] Figures 5A to 5G The results of elemental analysis of cross sections of the component carrier according to exemplary embodiments of the present disclosure are shown respectively. Detailed Implementation

[0110] Figure 1 A schematic cross-sectional view through a component carrier 100 according to an exemplary embodiment of the present disclosure is shown. The component carrier 100 includes a stack 101 having an electrically insulating layer structure 102 and an additional electrically insulating layer structure 160 located on top. At the interface between the two electrically insulating layer structures 102, 160, an electrically conductive layer structure 104 is formed, which is patterned during manufacturing such that a patterned conductive structure 110 is disposed on the upper main surface 103 of the electrically insulating layer structure 102.

[0111] The patterned conductive structure 110 defines a contact interface 115 between the patterned conductive structure 110 and the surface 103 of the electrically insulating layer structure 102, such that the surface 103 is divided into a contact interface portion 120 (partially covered by the patterned conductive structure) and a free surface portion 130 (partially not covered by the patterned conductive structure).

[0112] As can be seen, the free surface portion 130 correspondingly includes a metal portion 150 located on top. The metal portion 150 may be provided in the form of particles / residues; in particular, the metal 150 may be provided in the form of surface-distributed particles or residues, thereby forming a porous layer and / or a discontinuous heterogeneous layer, which in any case is an interrupted layer / structure (indicated by reference numeral 154), thereby preventing physical and electrical connections between the two ends of the layer / structure (particularly between two adjacent portions of the patterned conductive structure 110). The metal 150 may not be provided as a continuous and uniform layer. Alternatively, at least a portion of the metal 150 may be provided as a continuous and uniform layer.

[0113] An additional electrically insulating layer structure 160 contacts the free surface portion 130 and the patterned conductive structure 110 to form a dielectric contact surface, wherein a metal portion 150 is at least partially disposed at the dielectric contact surface. The electrically insulating layer structure 102 and the additional electrically insulating layer structure 160 are at least partially in direct contact with the metal portion 150. Alternatively, the metal portion 150 may be completely enclosed by the electrically insulating layer structure 102 or the additional electrically insulating layer structure 160. Preferably, the metal portion 150 is configured to reduce / prevent and / or degrade or interfere with copper migration of the material of the patterned conductive structure 110 (e.g., between traces) and / or electrical conduction between adjacent portions of the patterned conductive structure 110. In a specific example, the metal portion 150 comprises or is composed of chromium. In another example, the metal portion 150 comprises a metal salt, wherein the metal is positively charged, for example, divalent or trivalent; in particular, the metal portion 150 comprises a metal oxide, i.e., chromium oxide. Additionally or alternatively, the metal portion includes at least one of nickel, zinc, titanium, manganese, tungsten, iron, sulfur, phosphorus, or tin. Optionally, the metal portion may include a shell-like structure, which may be open or closed and disposed on the outer surface of the metal material (particles). The shell-like structure may include an electrically insulating material, such as an organic material (epoxy) resin and / or an inorganic material (glass), which may have an additional effect on the migration of the metal, such as hindering migration.

[0114] The component carrier 100 may include an additional (conductive, particularly metallic) layer 155 on the patterned conductive structure 110, the additional layer 155 being made of a material different from that of the patterned conductive structure 110 and / or different from that of the metallic portion 150. The metallic portion 150 and / or the additional metallic portion 151 may include a non-metallic electrically conductive material, such as carbon, and particularly graphene. In examples, the additional metallic portion 151 includes nickel, zinc, iron, lead, manganese, and aluminum.

[0115] In an exemplary embodiment, the patterned conductive structure 110 (e.g., configured as a metallic trace) comprises copper, the metallic portion 150 comprises chromium, and the additional (metallic) layer 155 comprises zinc and / or nickel. Like the metallic portion 150, the additional layer 155 is in contact with the electrically insulating layer structure 102 and / or the additional electrically insulating layer structure 160. In other words, at least two different types of metallic portions (metallic portion 150 and additional metals 155 of the additional layer structures) are provided on the free surface portion 130. Alternatively, the free surface portion 130 may be provided such that it comprises only one of the metallic portions 150 and the additional metallic portion 155; preferably, the free surface portion 130 comprises only the metallic portion 150. The additional (conductive) layer 155 is in contact with the electrically insulating layer structure 102 and / or the additional electrically insulating layer structure 160. In the example, an additional (electrically conductive) layer structure 155 may be arranged at the side wall 111 of a portion of the patterned conductive structure 110.

[0116] The amount of metal portion 150 located on the free surface portion 130 preferably prevents the migration of electrically conductive material, particularly copper, between adjacent portions / parts of the patterned conductive structure 110. Additionally or alternatively, the migration of other electrically conductive materials, such as nickel, titanium, or gold, can be prevented. Additionally or alternatively, the particles / residues of the metal portion 150 are arranged to be spaced apart from each other such that the migration of electrically conductive material between adjacent portions of the patterned conductive structure 110 is prevented. To achieve this result, it is preferable that the amount of migration-preventing metal portion 150 (e.g., including chromium or metal portion made of chromium) per unit area is greater than the amount of other types of additional metal portion 155 (e.g., including nickel / zinc) that promote migration; for example, the amount of migration-preventing metal portion 150 (e.g., including chromium or metal portion made of chromium) per unit area is ten times the amount of other types of additional metal portion 155 (e.g., including nickel / zinc) that promote migration. On the other hand, preferably, the amount of metal portion 150 on the free surface portion 130 is such that the resistance generated between adjacent portions of the patterned conductive structure prevents electrical conduction between said adjacent portions. Additionally or alternatively, the particles / residues of the metal portion 150 are spaced apart from each other such that the resistance generated between adjacent portions of the patterned conductive structure prevents electrical conduction between said adjacent portions. In embodiments, the amount of metal portion 150 (per unit area) and / or additional metal portion 155 (per unit area) in the contact interface portion 120 is higher than that in the free surface portion 130. This may be related to the corresponding manufacturing method and thus can provide good electrical conductivity in the contact interface portion 120.

[0117] The patterned conductive structure 110 includes a lateral wall 111 defining a lateral edge 112 of the contact interface 115. The lateral wall 111 extends vertically (along the Z-axis) such that at the contact portion contacting the contact interface 115, the lateral wall 111 is at least partially recessed into the material of the patterned conductive structure 110 relative to the overall vertical extension of the lateral edge 112. A recess is formed at the corresponding bottom portion (trace root) of the patterned conductive structure 110. This recess can be filled with a dielectric material from a separate electrically insulating layer structure 160. In this way, migration of material from the patterned conductive structure 110 can be further prevented.

[0118] The recess may have a concave shape. Alternatively, the recess may have a convex portion. Preferably, the recessed portion may be metal-free (particles). Alternatively, the recessed portion may include metal.

[0119] The contact interface portion includes an additional metal portion (nickel, zinc), while the free surface portion may not contain an additional metal portion. Alternatively, the contact interface portion and the free surface portion may not contain any metal portion or additional metal portion, or may include metal portion and additional metal portion.

[0120] A structure 152 may also be provided, comprising a metal portion 150 (e.g., chromium) and an additional metal portion 151 (e.g., zinc / nickel). The structure 152 may be located at the contact interface portion 120 and / or the free surface portion 130 (not shown).

[0121] Furthermore, the contact interface 115 may include a metal portion 150, which is made of a different material 153 than the material of the patterned conductive structure 110 (i.e., not copper, but for example, chromium). It can be seen that, on the right side, a free surface portion 130 without the metal portion is provided (adjacent to the metal portions 152 / 153 arranged below a portion of the patterned conductive structure 110) (nevertheless, some metal residue may still remain on the free surface portion 130).

[0122] The metal portions 150 and 153 located below the portion of the patterned conductive structure 110 can be provided in the form of layers or particles. In addition, surface treatment portions (e.g., solder resist layer, gold layer) (not shown) can be applied.

[0123] Figure 2 A microscopic image of a cross section through the component carrier 100 according to an exemplary embodiment of the present disclosure is shown. Figure 2A patterned conductive structure 110 is shown on top of the surface 103 of the electrically insulating layer structure 102, thereby defining the contact interface portion 120 and the free surface portion 130. However, for clarity, the additional electrically insulating layer structure 160 is omitted in this figure. The properties of the metal portion 150 located at the free surface portion 130 prevent the migration of electrically conductive material, particularly copper, between adjacent portions of the patterned conductive structure 110, as well as electrical conduction between adjacent portions of the patterned conductive structure 110. Additionally, the metal portion 150 located at the contact interface portion 120 can prevent or reduce the migration of material from the electrically conductive layer structure 104 into the electrically insulating layer structure 102.

[0124] As can be seen, each portion (trace) of the patterned conductive structure 110 includes a sidewall (lateral wall) 111 and an edge portion (lateral edge) 112 located at the contact interface 115. The patterned conductive structure 110 thus includes a lateral wall 111 defining the lateral edge 112 of the contact interface 115, wherein the lateral wall 111 extends vertically such that at the contact portion that contacts the contact interface 115, the lateral wall 111 is at least partially penetrating the material of the patterned conductive structure 110 relative to the overall vertical extension of the lateral edge 112.

[0125] In other words, the vertical extension of the lateral wall 111 tapers toward the contact interface portion 120, thereby forming a concave lateral edge 112 between the lateral wall 111 and the contact interface 115. Therefore, the lateral wall 111 of the patterned conductive structure 110 has a concave vertical extension in the region directly above the contact portion that contacts the contact interface 115. In particular, the lateral wall 111 of the patterned conductive structure 110 has a concave vertical extension toward the patterned conductive structure material 110 in the region directly above the contact portion that contacts the contact interface 115.

[0126] The sidewalls 111 of the patterned conductive structure 110 also have straight vertical extensions in the region above the contact portion with the contact interface 115. The sidewalls 111 of the patterned conductive structure 110 may also have tapered extensions in the region above the contact portion with the contact interface 115, for example, tapering extensions oriented away from the surface 103 of the electrically insulating layer structure 102. The bottom / top and / or left / right tapering can be symmetrical. The trace roots are etched to a certain extent, i.e., the trace roots are etched to a certain extent at the edge 112, and the dielectric material of the additional electrically insulating material can extend beyond the vertical extensions of the sidewalls 111. The specific shape of the trace roots (and particularly the surface roughness) can further prevent the migration of material from the patterned conductive structure 110.

[0127] It can also be seen that the roughness of the side walls 111 (and the top wall) is in a similar numerical range to the roughness of the patterned conductive structure 110 at the contact interface 115. The surface 103 of the electrically insulating layer structure 102 also includes an irregular shape due to surface roughness. The roughness can reflect the fabrication steps of applying an aggressive (rapid) etch solution. In this example, the side walls 111 are straight (except for the side edges 112). The roughness (Rz) of the side walls 111 and / or the top of the patterned conductive structure 110 can be in the range between 50 nm and 2 µm, and in particular, the roughness (Rz) of the side walls 111 and / or the top of the patterned conductive structure 110 can be in the range between 300 nm and 1 µm.

[0128] Figure 4A A conventional circuit board 200 is shown (see Figure 3 The circuit board 200 is shown in top view, having a contact interface portion 220 and a free surface portion 230. An etching step has been performed, resulting in a fairly low surface roughness. Such a structure may actually promote the migration of copper trace material.

[0129] Figure 4B A component carrier 100 according to an exemplary embodiment of the present disclosure is shown (e.g., Figure 2 A top view of the component (the carrier). (and) Figure 4A In contrast, two etching steps have already been performed, resulting in a higher surface roughness, which further prevents migration. Furthermore, due to the second etching step, a heterogeneous layer of metal portion 150 is formed on the free surface portion 130, comprising individual particles of metal portion 150 and / or aggregates of at least two spaced-apart particles of metal portion 150. Additionally, a further heterogeneous layer of another metal portion 151 is formed on the free surface portion 130, comprising individual particles of another metal portion 151 and / or aggregates of at least two spaced-apart particles of another metal portion 151.

[0130] Figures 5A to 5G Chemical elemental analysis results for cross-sections of the component carrier 100 according to exemplary embodiments of the present disclosure are shown. Scanning transmission electron microscopy (STEM) was applied to these measurements. Each figure shows the distribution of a specific chemical element.

[0131] Figure 5AThe interface between the electrically insulating layer structure 102 and another electrically insulating layer structure 160 is shown. The interface is rough in shape, as can be seen from its corrugated portions, edges, and corners. The interface includes particles / residues of the metal portion 150 and other metal portions. The metal structure 150 is non-planar, wherein the roughness of the metal structure corresponds to the roughness of the free surface portion of the electrically insulating layer structure 102.

[0132] Figure 5B The distribution of elemental copper is shown.

[0133] Figure 5C The distribution of elemental nickel is shown. At the contact interface portion 120, a region with a lower amount / concentration of nickel particles can be observed compared to the remaining (other) metallic material. This is evident from the darker / lower intensity markings. This may indicate a discontinuous metallic structure, thus inhibiting / preventing migration.

[0134] Figure 5D The distribution of elemental sulfur is shown.

[0135] Figure 5E The distribution of elemental zinc is shown. At the contact interface portion 120, a region with a lower amount / concentration of zinc particles can be observed compared to the remaining (other) metallic material. This is evident from the darker / lower intensity markings. This may indicate a discontinuous metallic structure, thus inhibiting / preventing migration.

[0136] Figure 5F The distribution of elemental chromium is shown. At the contact interface portion 120, a region with a higher amount / concentration of chromium particles can be observed. This is evident from the brighter / higher intensity markings. This may indicate a continuous metallic structure; however, even so, migration phenomena can be mitigated / prevented.

[0137] Figure 5G The distribution of element phosphorus is shown.

[0138] As can be seen, each element follows a different distribution pattern, allowing the anti-migration metal portions (e.g., chromium) and the migration-promoting metal portions (e.g., zinc / nickel) to be distributed in different ways. In this regard, process parameters can be adjusted to prevent rather than promote (copper) migration, thereby enabling the production of high-performance component carriers.

[0139] Industrial applicability This disclosure provides a component carrier and a method for manufacturing the same. The component carrier includes a stack having at least one electrically insulating layer structure and at least one electrically conductive layer structure, and includes the following features: i) the at least one electrically conductive layer structure includes a patterned conductive structure disposed on one surface of the surface of the at least one electrically insulating layer structure; ii) the patterned conductive structure defines a contact interface between the patterned conductive structure and the surface of the at least one electrically insulating layer structure, such that the surface is divided into at least one contact interface portion and at least one free surface portion; iii) the nature of the metal portion at the at least one free surface portion prevents the migration of electrically conductive material, particularly copper, between adjacent portions of the patterned conductive structure; and iv) the patterned conductive structure includes at least one lateral wall defining a lateral edge of the contact interface, wherein the lateral wall extends vertically such that at the contact portion with the contact interface, the lateral wall is at least partially recessed toward the material of the patterned conductive structure relative to the overall vertical extension of the lateral edge.

[0140] Furthermore, it is understood that the component carrier and its manufacturing method in this disclosure are reproducible and can be used in various industrial fields, such as the technical field of printed circuit boards or IC substrates.

[0141] Figure Labels 100 component carriers 101 Stacked Components 102 Electrical insulation layer structure 103 Surface of the electrical insulation layer structure 104 Electrically Conductive Layer Structure 110 Graphical Transmission Structure 111 Lateral wall 112 Lateral edge 115 Contact Interface 120 Contact Interface Section 130 Free Surface Section 150 Metal parts, metal structures 151 Other metal parts 152 Structure of the metal parts and other metal parts 153 Other materials that differ from those used in patterned conductive structures 154. Gap, discontinuous region.

Claims

1. A component carrier (100) comprising a stack (101) having at least one electrically insulating layer structure (102) and at least one electrically conductive layer structure (104). in, The at least one electrically conductive layer structure (104) includes a patterned conductive structure (110) disposed on one of the surfaces (103) of at least one of the electrically insulating layer structures (102); The patterned conductive structure (110) defines a contact interface (115) between the patterned conductive structure (110) and the surface (103) of at least one of the electrically insulating layer structures (102), such that the surface (103) is divided into at least one contact interface portion (120) and at least one free surface portion (130). The metal portion (150) located at the at least one free surface portion (130) has properties that prevent the migration of electrically conductive material between adjacent portions of the patterned conductive structure (110); and The patterned conductive structure (110) includes at least one lateral wall (111) that defines a lateral edge (112) of the contact interface (115), wherein the lateral wall (111) extends vertically such that at a contact portion that contacts the contact interface (115), the lateral wall (111) is at least partially recessed toward the material of the patterned conductive structure (110) relative to the overall vertical extension of the lateral edge (112).

2. A component carrier (100) comprising a stack (101) having at least one electrically insulating layer structure (102) and at least one electrically conductive layer structure (104). in, The at least one electrically conductive layer structure (104) includes a patterned conductive structure (110) disposed on one of the surfaces (103) of at least one of the electrically insulating layer structures (102); The patterned conductive structure (110) defines a contact interface (115) between the patterned conductive structure (110) and the surface (103) of at least one of the electrically insulating layer structures (102), such that the surface (103) is divided into at least one contact interface portion (120) and at least one free surface portion (130). The contact interface (115) includes a metal part (150), wherein the metal part (150) is made of another material (153), which is different from the material of the patterned conductive structure (110).

3. The component carrier (100) according to claim 2, wherein, The at least one free surface portion (130) is free of metal.

4. The component carrier (100) according to claim 1. in, The properties of the metal part (150) include one of the following: the amount of the metal part (150), the type of the metal part (150), and the distribution of the metal part (150).

5. The component carrier (100) according to claim 1 or 4. in, The amount of metal portion (150) located on the at least one free surface portion (130) is such that the resistance generated between adjacent portions of the patterned conductive structure (110) prevents electrical conduction between the adjacent portions of the patterned conductive structure (110).

6. The component carrier (100) according to claim 1, 4 or 5. in, The particles / residues of the metal part (150) are arranged in a spaced-apart manner, such that the resistance generated between adjacent portions of the patterned conductive structure (110) prevents electrical conduction between the adjacent portions of the patterned conductive structure (110).

7. The component carrier (100) according to any one of the preceding claims. in, The metal portion (150) exists in the form of at least one of particles and residues, particularly, the metal portion (150) exists in the form of at least one of surface-distributed particles and residues; and / or The metal part (150) forms a metal structure.

8. The component carrier (100) according to any one of the preceding claims. in, The side wall (111) of the graphic conductive structure (110) has a vertical straight extension (z) in the region above the contact portion that contacts the contact interface (115).

9. The component carrier (100) according to any one of the preceding claims. in, The side wall (111) of the patterned conductive structure (110) has a tapered extension in the region above the contact portion that contacts the contact interface (115). In particular, the tapering extension tapers toward a direction oriented away from the surface of at least one of the electrically insulating layer structures (102).

10. The component carrier (100) according to any one of the preceding claims. in, The side wall (111) of the patterned conductive structure (110) has a vertical extension in the region above the contact portion that contacts the contact interface (115), the vertical extension being concave, and in particular, the vertical extension being concave in the material of the patterned conductive structure (110).

11. The component carrier (100) according to any one of the preceding claims. in, The roughness of the side wall (111) is within a comparable range to the roughness of the patterned conductive structure (110) at the contact interface (115). In particular, the roughness of the side wall (111) is within a similar range to the roughness of the patterned conductive structure (110) at the contact interface (115).

12. The component carrier (100) according to any one of the preceding claims, wherein the component carrier (100) further comprises: An additional electrical insulating layer structure (160) is in contact with the free surface portion (130) and the patterned conductive structure (110).

13. The component carrier (100) according to claim 12. in, The metal portion (150) is at least partially disposed between the electrical insulating layer structure (102) and the additional electrical insulating layer structure (160).

14. The component carrier (100) according to any one of the preceding claims. in, At least a portion of the contact area of ​​the contact interface (115) that is recessed toward the patterned conductive structure (110) is in direct contact with the additional electrical insulating layer structure (160).

15. The component carrier (100) according to any one of the preceding claims. in, At least one portion of the patterned conductive structure (110) includes an electrical conductive trace, and in particular, at least one portion of the patterned conductive structure (110) includes adjacent electrical conductive traces.

16. The component carrier (100) according to any one of the preceding claims. in, At least one portion of the patterned conductive structure (110) includes at least one pad / protrusion, particularly wherein, The at least one pad / protrusion is adjacent to another portion of the patterned conductive structure (110), and in particular, the other portion includes at least one electrically conductive trace.

17. The component carrier (100) according to any one of the preceding claims. in, The patterned conductive structure (110) includes at least one additional electrically conductive layer structure (155), which is made of a material different from that of the patterned conductive structure (110). Specifically, the additional electrically conductive layer structure (155) is in contact with the electrically insulating layer structure (102) and / or the additional electrically insulating layer structure (160).

18. The component carrier (100) according to claim 17. in, The additional electrically conductive layer structure (155) includes the metal portion (150) disposed at the contact interface (115) located between the surface (103) of the patterned conductive structure (110) and the electrically insulating layer structure (102). In particular, the additional electrically conductive layer structure (155) is made of a material comprising at least one chemical composition as the metal portion (150) located on the free surface portion (130).

19. The component carrier (100) according to any one of the preceding claims. in, The metal portion (150) comprises a material different from that of the electrically conductive layer structure (110), and in particular, the metal portion (150) comprises at least one of chromium, nickel, zinc, titanium, manganese, tungsten, iron, and tin.

20. The component carrier (100) according to any one of the preceding claims. in, The contact area where the side wall (111) contacts the contact interface (115) does not include the metal part (150).

21. The component carrier (100) according to any one of the preceding claims. in, The surface of the at least one electrically insulating layer structure (102) includes an irregular shape. In particular, the surface of the at least one electrically insulating layer structure (102) includes roughness. More particularly, the surface of the at least one electrically insulating layer structure (102) includes at least one of an edge portion, a corner portion, and a corrugated portion.

22. The component carrier (100) according to any one of the preceding claims. in, The metal portion (150) comprises an agglomeration of at least two particles, and in particular, the metal portion (150) comprises an agglomeration of at least four particles.

23. A method for manufacturing a component carrier (100), the method comprising: Provides an electrical insulation layer structure (102); The electrically conductive layer structure (104) is arranged on the surface (103) of the electrically insulating layer structure (102); and The electrically conductive layer structure (104) is patterned to form a patterned electrically conductive structure (110) such that: The patterned conductive structure (110) defines a contact interface (115) between the patterned conductive structure (110) and the surface (103) of the at least one electrically insulating layer structure (102), such that the surface (103) is divided into at least one contact interface portion (120) and at least one free surface portion (130). The patterned conductive structure (110) includes at least one lateral wall (111) defining a lateral edge (112) of the contact interface (115), wherein the lateral wall (111) extends vertically such that: at a contact portion contacting the contact interface (115), the lateral wall (111) is at least partially recessed into the material of the patterned conductive structure (110) relative to the entire vertical extension of the lateral edge (112); and At least a portion of the metal portion (150) located at the at least one free surface portion (130) is removed, thereby preventing the migration of the electrically conductive material between adjacent portions of the patterned conductive structure (110), in particular, the electrically conductive material is copper.

24. The method according to claim 23, in, Patterning includes etching, and in particular, the etching is flash etching.

25. The method according to claim 23 or 24, in, At least a portion of the metal part (150) can be removed by adjusting the process parameters.

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