Conductive substrate with filtering function, carrier board wiring structure and manufacturing method thereof

Abstract

The application discloses a manufacturing method of a through substrate with a filtering function, which comprises the following steps: preparing a core layer, forming a first through hole and a second through hole in the core layer, forming a sacrificial copper layer on the inner wall of the first through hole and the surface of the core layer and a metal layer on the inner wall of the second through hole, forming a metal column in the first through hole, forming a lower insulating layer covering the bottom end of the metal column on the lower surface of the core layer and a lower insulating column in the second through hole, forming a magnet between the inner wall of the first through hole and the metal column to wrap the metal column in the axial direction to obtain a first through column, forming an upper insulating layer covering the top end of the metal column on the upper surface of the core layer and an upper insulating column in the second through hole to obtain a second through column, and removing the upper insulating layer, the lower insulating layer and the residual sacrificial copper column layer and grinding the end portions of the first through column and the second through column respectively. A through substrate with a filtering function, a carrier board wiring structure and a manufacturing method thereof are also provided.

Description

Technical Field

[0001] This invention relates to the field of semiconductor packaging, specifically to a conductive substrate with filtering function, a carrier board wiring structure, and a method for manufacturing the same. Background Technology

[0002] With the rapid development of electronic technology, the size of various electronic products is constantly decreasing, the operating frequency is constantly increasing, and the size of inductive devices is also becoming smaller and more integrated. Although embedded wiring has been widely adopted, the existing manufacturing methods for magnetic wiring are complex, have long production cycles, low quality yields, and high production costs. The complex magnet formation process results in low wiring density, which cannot meet the requirements of high integration, miniaturization, and high-density wiring. Summary of the Invention

[0003] The embodiments of the present invention relate to providing a conductive substrate with filtering function, a carrier board wiring structure, and a method for manufacturing the same.

[0004] The first aspect of this invention relates to a method for manufacturing a conductive substrate with filtering function, comprising the following steps:

[0005] (a) Prepare a core layer and form at least one first through hole and at least one second through hole in the core layer, respectively penetrating the core layer along the height direction; (b) A sacrificial copper layer is formed on the inner wall of the at least one first via and on the surface of the core layer, and a metal layer is formed on the inner wall of the at least one second via. (c) A metal pillar is formed within the at least one first through hole; (d) Etching a portion of the sacrificial copper layer on the lower surface of the core layer to expose the bottom end of the metal pillar, forming a lower insulating layer on the lower surface of the core layer covering the bottom end of the metal pillar, and forming a lower insulating pillar within the at least one second via. (e) Etch a portion of the sacrificial copper layer on the upper surface of the core layer and the sacrificial copper layer on the inner wall of the at least one first via, and form a magnet that wraps around the metal pillar along the axial direction between the inner wall of the at least one first via and the metal pillar to obtain the first via pillar layer. (f) Continue etching a portion of the sacrificial copper layer on the upper surface of the core layer, forming an upper insulating layer on the upper surface of the core layer that covers the top of the metal pillar, and forming an upper insulating pillar in the at least one second via. The upper insulating pillar and the lower insulating pillar together form an insulating pillar that fills the second via, thus obtaining a second via layer. (g) Remove the sacrificial copper layer remaining on the upper insulating layer, the lower insulating layer and the upper and lower surfaces of the core layer, and grind the ends of the first conductive pillar layer and the second conductive pillar layer flat, so that the ends of the first conductive pillar layer and the second conductive pillar layer are respectively flush with the core layer, to obtain a conductive substrate with filtering function.

[0006] In some implementations, step (d) includes: (d1) A first photoresist layer and a second photoresist layer are applied to the upper and lower surfaces of the core layer, respectively, and the second photoresist layer is exposed and developed to form a second feature pattern; (d2) Etch a portion of the sacrificial copper layer on the exposed lower surface of the core layer in the second feature pattern to expose the bottom end of the metal pillar; (d3) Remove the first photoresist layer and the second photoresist layer; (d4) An insulating material is laminated on the lower surface of the core layer to form a lower insulating layer covering the bottom end of the metal pillar, and a lower insulating pillar is formed in the at least one second through hole.

[0007] In some implementations, step (e) includes: (e1) A third photoresist layer is applied to the upper surface of the core layer, and the third photoresist layer is exposed and developed to form a third feature pattern that exposes the top of the at least one first via. (e2) Etch a sacrificial copper layer on the inner wall of the at least one first via in the third feature pattern; (e3) Remove the third photoresist layer; (e4) A magnet is formed between the inner wall of the at least one first through hole and the metal pillar, which wraps around the metal pillar in an axial direction; (e5) Grind the magnet and the metal pillar to obtain the first conductive pillar layer.

[0008] In some embodiments, step (e4) includes forming a magnet that axially wraps around the metal post between the inner wall of the at least one first through hole and the metal post by screen printing.

[0009] In some implementations, step (f) includes: (f1) A fourth photoresist layer is applied to the upper and lower surfaces of the core layer respectively, and the fourth photoresist layer is exposed and developed to form a fourth feature pattern; (f2) Etching a portion of the sacrificial copper layer on the exposed upper surface of the core layer in the fourth feature pattern; (f3) Remove the fourth photoresist layer; (f4) An insulating material is laminated on the upper surface of the core layer to form an upper insulating layer covering the top of the metal pillar, and an upper insulating pillar is formed in the at least one second through hole. The upper insulating pillar and the lower insulating pillar together form an insulating pillar that fills the second through hole, thus obtaining a second through pillar layer.

[0010] A second aspect of the present invention relates to a method for fabricating a carrier board wiring structure, comprising the following steps: (a) A conductive substrate with filtering function is prepared by the method for manufacturing a conductive substrate with filtering function according to the first aspect of the present invention; (b) A first circuit layer and a second circuit layer are formed on the upper and lower surfaces of the conductive substrate, respectively, and the first circuit layer and the second circuit layer are connected through the first conductive post layer or the second conductive post layer.

[0011] In some implementation schemes, it also includes: (c) Following step (b), a first augmentation layer and a second augmentation layer are formed on the first circuit layer and the second circuit layer, respectively. A first copper pillar layer and a second copper pillar layer are formed in the first augmentation layer and the second augmentation layer, respectively. A third circuit layer and a fourth circuit layer are formed on the surfaces of the first augmentation layer and the second augmentation layer, respectively. The first circuit layer and the third circuit layer are connected through the first copper pillar layer, and the second circuit layer and the fourth circuit layer are connected through the second copper pillar layer. (j) A third augmentation layer and a fourth augmentation layer are formed on the third circuit layer and the fourth circuit layer, respectively. A third copper pillar layer and a fourth copper pillar layer are formed in the third augmentation layer and the fourth augmentation layer, respectively. A fifth circuit layer and a sixth circuit layer are formed on the surface of the third augmentation layer and the fourth augmentation layer, respectively. The third circuit layer and the fifth circuit layer are connected through the third copper pillar layer. The fourth circuit layer and the sixth circuit layer are connected through the fourth copper pillar layer.

[0012] The third aspect of the present invention relates to a conductive substrate with filtering function, which is prepared by the method for manufacturing a conductive substrate with filtering function described in the first aspect of the present invention.

[0013] In some implementations, the system includes a core layer, a first conductive post layer and a second conductive post layer that extend through the core layer along the height direction. The conductive post in the first conductive post layer includes a metal post and a magnet that wraps around the metal post along the axial direction. The conductive post in the second conductive post layer includes an insulating post and a metal layer that wraps around the insulating post along the axial direction. The first conductive post layer has a filtering function.

[0014] In some implementations, the end of the first conductive post layer is flush with or higher than the core layer, and the end of the second conductive post layer is flush with or higher than the core layer.

[0015] In some embodiments, the insulating post is selected from pure resin or resin containing glass fiber.

[0016] In some embodiments, the core layer comprises polyimide, epoxy resin, bismaleimide / triazine resin, polyphenylene ether, polyacrylate, prepreg, film-like organic resin, or combinations thereof.

[0017] In some embodiments, the metal pillar comprises a hybrid metal that is etch-resistant and has low resistivity and high thermal conductivity.

[0018] A fourth aspect of the present invention provides a carrier board wiring structure, including the conductive substrate with filtering function described in the first aspect of the present invention.

[0019] In some embodiments, the system further includes a first circuit layer on a first side of the conductive substrate and a second circuit layer on a second side of the conductive substrate, wherein the first circuit layer and the second circuit layer are electrically connected through the first conductive post layer or the second conductive post layer.

[0020] In some embodiments, the system further includes a first augmentation layer on the first circuit layer, a first copper pillar layer within the first augmentation layer, a third circuit layer on the surface of the first augmentation layer, a third augmentation layer on the third circuit layer, a third copper pillar layer within the third augmentation layer, and a fifth circuit layer on the third augmentation layer, wherein the first circuit layer and the third circuit layer are electrically connected through the first copper pillar layer, and the third circuit layer and the fifth circuit layer are electrically connected through the third copper pillar layer.

[0021] In some embodiments, the system further includes a second augmentation layer on the second circuit layer, a second copper pillar layer within the second augmentation layer, a fourth circuit layer on the surface of the second augmentation layer, a fourth augmentation layer on the fourth circuit layer, a fourth copper pillar layer within the fourth augmentation layer, and a sixth circuit layer on the fourth augmentation layer, wherein the second circuit layer and the fourth circuit layer are electrically connected through the second copper pillar layer, and the fourth circuit layer and the sixth circuit layer are electrically connected through the fourth copper pillar layer.

[0022] As can be seen from the above, the conductive substrate with filtering function, the carrier board wiring structure, and the manufacturing method thereof provided by the present invention do not require the addition of an insulating layer when wiring inside the magnet. A magnetic cavity is directly formed around the metal pillar, increasing the density of the magnetic wiring and meeting the development trend of high integration, miniaturization, and micro-miniaturization. The metal pillars inside the magnet are made of a low resistivity, high thermal conductivity hybrid metal material, which reduces the resistance of the conductive pillar and can quickly conduct heat out of the magnet, improving the reliability of embedded magnetic products. The manufacturing method of the conductive substrate with filtering function shortens the manufacturing process of the magnetic substrate, simplifies the production process, improves the production yield, and reduces the production cost. Attached Figure Description

[0023] To better understand the present invention and to illustrate embodiments thereof, reference is made below purely by way of example to the accompanying drawings.

[0024] When referring specifically to the accompanying drawings, it must be emphasized that the particular illustrations are exemplary and intended only to illustrately discuss preferred embodiments of the invention, and are presented for the purpose of providing illustrations that are considered most useful and readily understood for describing the principles and concepts of the invention. In this regard, no attempt is made to illustrate the structural details of the invention to a degree beyond what is necessary for a basic understanding of the invention; the description with reference to the drawings enables those skilled in the art to recognize how various forms of the invention can be practically embodied. In the drawings: Figure 1 This is a cross-sectional schematic diagram of a conductive substrate 100 with filtering function according to an embodiment of the present invention; Figure 2 This is a cross-sectional schematic diagram of a carrier board wiring structure 200 according to an embodiment of the present invention; Figures 3(a) to 3(m) show cross-sectional schematic diagrams of the intermediate structures in each step of the manufacturing method of the carrier wiring structure 200 of one embodiment of the present invention. Detailed Implementation

[0025] With the rapid development of electronic technology, the size of various electronic products is constantly decreasing, the operating frequency is constantly increasing, and the size of inductive devices is also becoming smaller and the integration is becoming higher and higher.

[0026] In existing technologies, the fabrication of magnetic wiring is achieved by embedding. For example, openings are made on the substrate using mechanical drilling, mechanical milling, and laser cutting as needed. Magnetic material is then filled into the openings of the substrate using a filling method. After curing, excess carriers protruding or attached to the surface are removed using mechanical grinding to form the required magnet. A first through-hole is formed on the magnet using mechanical drilling or laser processing. Insulating material is then filled into the first through-hole using a filling method. The same grinding process is used to remove surface protrusions or excess insulating material attached to the surface. A second through-hole is then fabricated. The second through-hole is electroplated to form an internal conductor of the magnet, and then the insulation material for the second through-hole is filled.

[0027] However, the existing technology for completing the magnetic wiring on the substrate is complex: filling the magnet to create substrate openings, creating through-holes within the magnet to fill with an insulating layer, creating conductors within the insulating layer, and then filling with insulating material again, forming through-holes multiple times, requiring high alignment precision, making dense wiring impossible, and resulting in complex processes, long production cycles, and high production costs. Furthermore, the multiple grinding processes during the fabrication of the magnetic wiring substrate increase substrate expansion, contraction, and deformation, directly affecting substrate quality and yield, increasing production capacity pressure, and further increasing production costs.

[0028] To address this problem, the present invention provides a method for fabricating a conductive substrate with filtering function, comprising: preparing a core layer and forming at least one first via and at least one second via within the core layer; forming a sacrificial copper layer on the inner wall of the first via and the surface of the core layer; forming a metal layer on the inner wall of the second via; forming a metal pillar within the first via; forming a lower insulating layer covering the bottom of the metal pillar on the lower surface of the core layer; forming a lower insulating pillar within the second via; forming a magnet axially enclosing the metal pillar between the inner wall of the first via and the metal pillar to obtain a first conductive pillar; forming an upper insulating layer covering the top of the metal pillar on the upper surface of the core layer; forming an upper insulating pillar within the second via; the upper and lower insulating pillars together forming an insulating pillar filling the second via to obtain a second conductive pillar; removing the upper and lower insulating layers and the remaining sacrificial copper layer; and grinding the ends of the first and second conductive pillars respectively to obtain the final product.

[0029] This invention eliminates the need for an additional insulating layer when wiring inside the magnet, directly forming a magnetic cavity around the conductive posts, increasing the density of the magnetic wiring and meeting the development trends of high integration, miniaturization, and micro-miniaturization. The use of low-resistivity, high-thermal-conductivity hybrid metal materials to fabricate the conductive posts within the magnet reduces their resistance, enabling rapid heat dissipation from the magnet and improving the reliability of embedded magnetic products. Furthermore, the method for fabricating a conductive substrate with filtering capabilities shortens the fabrication process of the magnetic substrate, simplifies the manufacturing process, improves production yield, and reduces production costs.

[0030] Reference Figure 1The diagram shows a cross-sectional schematic of a conductive substrate 100 with filtering function. The conductive substrate 100 includes a core layer 101, which typically includes polyimide, epoxy resin, bismaleimide / triazine resin, polyphenylene ether, polyacrylate, prepreg, film-like organic resin, or combinations thereof.

[0031] The core layer 101 is provided with a first conductive post layer and a second conductive post layer that penetrate the core layer along the height direction. The conductive post in the first conductive post layer includes a metal post 1015 and a magnet 1019 that wraps around the metal post 1015 along the axial direction. The first conductive post has a filtering function.

[0032] The metal pillar 1015 may include an etch-resistant mixed metal with low resistivity and high thermal conductivity; for example, a silver mixture or a gold mixture, without limitation.

[0033] Typically, the first conductive post layer may include multiple conductive posts, whose cross-sectional dimensions and shapes may be the same or different. Preferably, the cross-sectional shape of the first conductive post layer is circular with uniform dimensions from top to bottom, which is more advantageous for filtering and improves the reliability of buried magnetic products by dissipating heat from the magnet.

[0034] The end of the first conductive pillar layer can be flush with the core layer 101 or it can be higher than the core layer 101; preferably, the end of the first conductive pillar layer is flush with the core layer 101.

[0035] The conductive pillars in the second conductive pillar layer include insulating pillars 1022 and a metal layer 1014 that wraps around the insulating pillars 1022 along the axial direction; wherein, the insulating pillars can be selected from pure resin or resin containing glass fiber.

[0036] Typically, the second conductive pillar layer may also include multiple conductive pillars, whose cross-sectional dimensions and shapes may be the same or different. Preferably, the cross-sectional shape of the second conductive pillar layer is circular and the dimensions are uniform from top to bottom, which is more advantageous for stable signal transmission.

[0037] The end of the second conductive pillar layer can be flush with the core layer or extend above the core layer; preferably, the end of the second conductive pillar layer is flush with the core layer.

[0038] Reference Figure 2 The diagram shows a cross-sectional view of the carrier board wiring structure 200. The carrier board wiring structure 200 includes, as shown below... Figure 1 The conductive substrate 100 with filtering function shown also includes a first circuit layer 2011 on a first side of the conductive substrate 100 and a second circuit layer 3011 on a second side of the conductive substrate 100. The first circuit layer 2011 and the second circuit layer 3011 are conductively connected through a first conductive pillar layer or a second conductive pillar layer.

[0039] A first extension layer 201 is provided on the first line layer 2011, a first copper pillar layer 2012 is provided inside the first extension layer 201, and a third line layer 4011 is provided on the surface of the first extension layer 201. The first line layer 2011 and the third line layer 4011 are connected through the first copper pillar layer 2012.

[0040] A third extension layer 401 is provided on the third circuit layer 4011, a third copper pillar layer 4012 is provided inside the third extension layer 401, and a fifth circuit layer 4013 is provided on the surface of the third extension layer 401. The third circuit layer 4013 and the fifth circuit layer 4013 are connected through the third copper pillar layer 4012.

[0041] A second extension layer 301 is provided on the second line layer 3011, a second copper pillar layer 3012 is provided inside the second extension layer 301, and a fourth line layer 5011 is provided on the surface of the second extension layer 301. The second line layer 3011 and the fourth line layer 5011 are connected through the second copper pillar layer 3012.

[0042] A fourth extension layer 501 is provided on the fourth circuit layer 5011, a fourth copper pillar layer 5012 is provided inside the fourth extension layer 501, and a sixth circuit layer 5013 is provided on the surface of the fourth extension layer 501. The fourth circuit layer 5011 and the sixth circuit layer 5013 are connected through the fourth copper pillar layer 5012.

[0043] A first solder mask layer 601 is provided outside the fifth circuit layer 4013, and a first solder mask opening 6011 is provided inside the first solder mask layer 601. A second solder mask layer 701 is provided outside the sixth circuit layer 5013, and a second solder mask opening 7011 is provided inside the second solder mask layer 701.

[0044] Referring to Figures 3(a) to 3(m), a cross-sectional schematic diagram of the intermediate structure of each step in the fabrication method of the carrier wiring structure 200 of one embodiment of the present invention is shown.

[0045] The manufacturing method includes the following steps: preparing a core layer 101, and forming at least one first through hole 1011 and at least one second through hole 1012 that penetrate the core layer 101 along the height direction—step (a), as shown in Figure 3(a).

[0046] Typically, the core layer 101 can be a double-sided copper-clad core board or a double-sided copper-free core board.

[0047] The core layer 101 may include polyimide, epoxy resin, bismaleimide / triazine resin, polyphenylene ether, polyacrylate, prepreg, film-like organic resin, or a combination thereof.

[0048] The core layer mentioned in this implementation plan can be a double-sided copper-clad core board or a double-sided copper-free core board, whichever needs to be selected. The subsequent process will only be demonstrated using a double-sided copper-free core board, but it is not limited to this method only.

[0049] Next, a sacrificial copper layer 1013 is formed on the inner wall of the first via 1011 and on the surface of the core layer 101, and a metal layer 1014 is formed on the inner wall of the second via 1012—step (b), as shown in Figure 3(b).

[0050] Typically, metal seed layers can be formed on the inner wall of the first via 1011, the surface of the core layer 101, and the inner wall of the second via 1012 by chemical plating or sputtering, respectively. Then, the metal seed layers are electroplated to the required copper thickness to obtain the sacrificial copper layer 1013 and the metal layer 1014.

[0051] Then, a metal pillar 1015 is formed in the first through hole 1011—step (c), as shown in Figure 3(c).

[0052] Typically, a mixed metal material that is etch-resistant and has low resistivity and high thermal conductivity can be selected to make the metal pillar 1015; the mixed metal material can be a silver mixture or a gold mixture, etc., and there is no specific limitation.

[0053] In this implementation scheme, a low resistivity, high thermal conductivity hybrid metal material is used to make the metal pillar inside the magnet, which reduces the resistance of the metal pillar and enables rapid heat dissipation from the magnet, thereby improving the reliability of the embedded magnet product.

[0054] In this embodiment, a metal pillar 1015 can first be formed in the first through hole 1011 by screen printing, then cured, and finally mechanically ground to make the end of the metal pillar 1015 flush with the core layer 101.

[0055] Next, a first photoresist layer 1016 and a second photoresist layer 1017 are applied to the upper and lower surfaces of the core layer 101, respectively. The second photoresist layer 1017 is exposed and developed to form a second feature pattern. A portion of the sacrificial copper layer on the exposed lower surface of the core layer 101 is etched in the second feature pattern to expose the bottom end of the metal pillar 1015—step (d), as shown in Figure 3(d).

[0056] Typically, photoresist layers can be applied by laminating or coating.

[0057] Then, the first photoresist layer 1016 and the second photoresist layer 1017 are removed, and an insulating material is laminated on the lower surface of the core layer 101 to form a lower insulating layer 1021b covering the bottom end of the metal pillar 1015, and a lower insulating pillar 1022b is formed in the second through hole 1012—step (e), as shown in FIG3 (e).

[0058] Typically, insulating materials can be selected from pure resins or resins containing glass fibers, depending on the requirements.

[0059] Alternatively, the insulating material can be laminated by coating or lamination.

[0060] Next, a third photoresist layer 1018 is applied to the upper surface of the core layer 101, and the third photoresist layer 1018 is exposed and developed to form a third feature pattern that exposes the top of the first via 1011. The sacrificial copper layer on the inner wall of the first via 1011 is etched in the third feature pattern—step (f), as shown in Figure 3 (f).

[0061] Then, the third photoresist layer 1018 is removed, and a magnet 1019 is formed between the inner wall of the first through hole 1011 and the metal pillar 1015 along the axial direction to wrap around the metal pillar 1015—step (g), as shown in Figure 3 (g).

[0062] Typically, magnets 1019 can be formed by screen printing.

[0063] In this implementation scheme, the internal wiring of the magnet does not require an additional insulation layer. A magnetic cavity is directly formed around the metal pillar, increasing the density of the wiring with magnets and meeting the development trend of high integration, miniaturization, and micro-miniaturization.

[0064] Next, the magnet 1019 and the metal pillar 1015 are ground smooth to obtain the first conductive pillar layer—step (h), as shown in Figure 3 (h). Typically, the top of the first conductive pillar layer can be flush with the sacrificial copper layer 1013.

[0065] Then, a fourth photoresist layer is applied to the upper and lower surfaces of the core layer 101, and the fourth photoresist layer is exposed and developed to form a fourth feature pattern. A portion of the sacrificial copper layer on the exposed upper surface of the core layer 101 is etched in the fourth feature pattern. The fourth photoresist layer is removed, and an insulating material is laminated on the upper surface of the core layer 101 to form an upper insulating layer 1021a covering the top of the metal pillar 101. An upper insulating pillar is formed in the second via 1012. The upper insulating pillar and the lower insulating pillar 1022b together form an insulating pillar 1022 filling the second via 1012. The metal layer 1014 and the insulating pillar 1022 together form the second via layer—step (i), as shown in Figure 3(i).

[0066] Next, the sacrificial copper layers remaining on the upper insulating layer 1021a, the lower insulating layer 1021b, and the upper and lower surfaces of the core layer 101 are removed, and the ends of the first and second conductive pillar layers are ground flat respectively. The ends of the first and second conductive pillar layers are flush with the core layer 101, thus obtaining the conductive substrate 100 with filtering function—step (j), as shown in Figure 3 (j).

[0067] Typically, the sacrificial copper layer remaining on the upper insulating layer 1021a, lower insulating layer 1021b, and the upper and lower surfaces of the core layer 101 can be removed by mechanical grinding.

[0068] In this embodiment, the fabrication process of the magnetic substrate is shortened, the production process is simplified, the production yield is improved, and the production cost is reduced.

[0069] Then, a first circuit layer 2011 and a second circuit layer 3011 are formed on the upper and lower surfaces of the conductive substrate 100, respectively. The first circuit layer 2011 and the second circuit layer 3011 are connected through a first conductive post layer or a second conductive post layer to obtain a carrier board wiring structure with filtering function—step (k), as shown in Figure 3 (k).

[0070] Typically, it can be prepared through the following steps: A first metal seed layer and a second metal seed layer are formed on the upper and lower surfaces of the conductive substrate 100, respectively. A fifth photoresist layer and a sixth photoresist layer are applied on the first metal seed layer and the second metal seed layer, respectively, and the fifth feature pattern and the sixth feature pattern are formed by exposure and development. The first circuit layer 2011 and the second circuit layer 3011 are formed by electroplating in the fifth feature pattern and the sixth feature pattern, respectively; Remove the fifth and sixth photoresist layers, and etch the exposed first and second metal seed layers.

[0071] Next, a first augmentation layer 201 and a second augmentation layer 301 are formed on the first circuit layer 2011 and the second circuit layer 3011, respectively. A first copper pillar layer 2012 and a second copper pillar layer 3012 are formed in the first augmentation layer 201 and the second augmentation layer 301, respectively. A third circuit layer 4011 and a fourth circuit layer 5011 are formed on the surfaces of the first augmentation layer 201 and the second augmentation layer 301, respectively. The first circuit layer 2011 and the third circuit layer 4011 are connected through the first copper pillar layer 2012, and the second circuit layer 3011 and the fourth circuit layer 5011 are connected through the second copper pillar layer 3012—step (l), as shown in Figure 3(l).

[0072] Typically, an addendum, a copper pillar layer within the addendum, and a circuit layer on the surface of the addendum can be prepared by the following process: laser drilling within the addendum → creating a seed layer on the surface of the addendum and the sidewalls and bottom of the hole → applying a photoresist layer on the seed layer → exposure and development to form a feature pattern → electroplating in the feature pattern to form a circuit layer and a copper pillar layer → removing the photoresist layer and etching the exposed seed layer.

[0073] Finally, a third add-on layer 401 and a fourth add-on layer 501 are formed on the third circuit layer 4011 and the fourth circuit layer 5011, respectively. A third copper pillar layer 4012 and a fourth copper pillar layer 5012 are formed inside the third add-on layer 4011 and the fourth add-on layer 5011, respectively. A fifth circuit layer 4013 and a sixth circuit layer 5013 are formed on the surfaces of the third add-on layer 401 and the fourth add-on layer 501, respectively. The third circuit layer 4011 and the fifth circuit layer 4013 are connected through the third copper pillar layer 4012, and the fourth circuit layer 5011 and the sixth circuit layer 5013 are connected through the fourth copper pillar layer 5012. A first solder mask layer 601 is formed outside the third add-on layer 401, and a 6011 is formed inside the first solder mask layer 601. A second solder mask layer 701 is formed outside the fourth add-on layer 501, and a 7011 is formed inside the second solder mask layer 701, resulting in the carrier board wiring structure 200—step (m), as shown in Figure 3 (m). Those skilled in the art will recognize that the present invention is not limited to the specific illustrations and descriptions in the context. Furthermore, the scope of the invention is defined by the appended claims, including combinations and sub-combinations of the various technical features described above, as well as variations and modifications thereof, which will be foreseen by those skilled in the art upon reading the foregoing description.

[0074] In the claims, the term "comprising" and its variations, such as "including" or "containing," means that the listed components are included, but generally do not exclude other components.

Claims

1. A method for fabricating a conductive substrate with filtering function, comprising the following steps: (a) Prepare a core layer and form at least one first through hole and at least one second through hole in the core layer, respectively penetrating the core layer along the height direction; (b) A sacrificial copper layer is formed on the inner wall of the at least one first via and on the surface of the core layer, and a metal layer is formed on the inner wall of the at least one second via. (c) A metal pillar is formed within the at least one first through hole; (d) Etching a portion of the sacrificial copper layer on the lower surface of the core layer to expose the bottom end of the metal pillar, forming a lower insulating layer on the lower surface of the core layer covering the bottom end of the metal pillar, and forming a lower insulating pillar within the at least one second via. (e) Etch a portion of the sacrificial copper layer on the upper surface of the core layer and the sacrificial copper layer on the inner wall of the at least one first via, and form a magnet that wraps around the metal pillar axially between the inner wall of the at least one first via and the metal pillar to obtain the first via layer. (f) Continue etching a portion of the sacrificial copper layer on the upper surface of the core layer, forming an upper insulating layer covering the top of the metal pillar on the upper surface of the core layer, and forming an upper insulating pillar in the at least one second via. The upper insulating pillar and the lower insulating pillar together form an insulating pillar filling the second via, thus obtaining the second via layer. (g) Remove the sacrificial copper layer remaining on the upper insulating layer, the lower insulating layer and the upper and lower surfaces of the core layer, and grind the ends of the first conductive pillar layer and the second conductive pillar layer respectively, so that the ends of the first conductive pillar layer and the ends of the second conductive pillar layer are flush with the core layer, to obtain a conductive substrate with filtering function.

2. The manufacturing method according to claim 1, wherein step (d) comprises: (d1) A first photoresist layer and a second photoresist layer are applied to the upper and lower surfaces of the core layer, respectively, and the second photoresist layer is exposed and developed to form a second feature pattern; (d2) Etch a portion of the sacrificial copper layer on the exposed lower surface of the core layer in the second feature pattern to expose the bottom end of the metal pillar; (d3) Remove the first photoresist layer and the second photoresist layer; (d4) An insulating material is laminated on the lower surface of the core layer to form a lower insulating layer covering the bottom end of the metal pillar, and a lower insulating pillar is formed in the at least one second through hole.

3. The manufacturing method according to claim 1, wherein step (e) comprises: (e1) A third photoresist layer is applied to the upper surface of the core layer, and the third photoresist layer is exposed and developed to form a third feature pattern that exposes the top of the at least one first via. (e2) Etch a sacrificial copper layer on the inner wall of the at least one first via in the third feature pattern; (e3) Remove the third photoresist layer; (e4) A magnet is formed between the inner wall of the at least one first through hole and the metal pillar, which wraps around the metal pillar in an axial direction; (e5) Grind the magnet and the metal pillar to obtain the first conductive pillar layer.

4. The manufacturing method according to claim 3, wherein step (e4) includes forming a magnet that axially wraps around the metal pillar between the inner wall of the at least one first through hole and the metal pillar by screen printing.

5. The manufacturing method according to claim 1, wherein step (f) comprises: (f1) A fourth photoresist layer is applied to the upper and lower surfaces of the core layer respectively, and the fourth photoresist layer is exposed and developed to form a fourth feature pattern; (f2) Etching a portion of the sacrificial copper layer on the exposed upper surface of the core layer in the fourth feature pattern; (f3) Remove the fourth photoresist layer; (f4) An insulating material is laminated on the upper surface of the core layer to form an upper insulating layer covering the top of the metal pillar, and an upper insulating pillar is formed in the at least one second through hole. The upper insulating pillar and the lower insulating pillar together form an insulating pillar filling the second through hole, and the metal layer and the insulating pillar together form a second through pillar layer.

6. A method for fabricating a carrier board wiring structure, comprising the following steps: (a) A conductive substrate with filtering function is prepared by the method of fabricating a conductive substrate with filtering function according to any one of claims 1 to 5; (b) A first circuit layer and a second circuit layer are formed on the upper and lower surfaces of the conductive substrate, respectively, and the first circuit layer and the second circuit layer are connected through the first conductive post layer or the second conductive post layer.

7. The manufacturing method according to claim 6 further includes: (c) Following step (b), a first augmentation layer and a second augmentation layer are formed on the first circuit layer and the second circuit layer, respectively. A first copper pillar layer and a second copper pillar layer are formed in the first augmentation layer and the second augmentation layer, respectively. A third circuit layer and a fourth circuit layer are formed on the surfaces of the first augmentation layer and the second augmentation layer, respectively. The first circuit layer and the third circuit layer are connected through the first copper pillar layer, and the second circuit layer and the fourth circuit layer are connected through the second copper pillar layer. (j) A third augmentation layer and a fourth augmentation layer are formed on the third circuit layer and the fourth circuit layer, respectively. A third copper pillar layer and a fourth copper pillar layer are formed in the third augmentation layer and the fourth augmentation layer, respectively. A fifth circuit layer and a sixth circuit layer are formed on the surface of the third augmentation layer and the fourth augmentation layer, respectively. The third circuit layer and the fifth circuit layer are connected through the third copper pillar layer. The fourth circuit layer and the sixth circuit layer are connected through the fourth copper pillar layer.

8. A conductive substrate with filtering function, which is prepared by the method of manufacturing a conductive substrate with filtering function according to any one of claims 1 to 5.

9. The conductive substrate with filtering function according to claim 8, comprising a core layer, a first conductive post layer and a second conductive post layer that penetrate the core layer along the height direction, wherein the conductive post in the first conductive post layer comprises a metal post and a magnet that wraps around the metal post along the axial direction, and the conductive post in the second conductive post layer comprises an insulating post and a metal layer that wraps around the insulating post along the axial direction, wherein the first conductive post layer has a filtering function.

10. The conductive substrate with filtering function according to claim 9, wherein the end of the first conductive pillar layer is flush with or higher than the core layer, and the end of the second conductive pillar layer is flush with or higher than the core layer.

11. The conductive substrate with filtering function according to claim 9, wherein the insulating pillar is selected from pure resin or resin containing glass fiber.

12. The conductive substrate with filtering function according to claim 9, wherein the core layer comprises polyimide, epoxy resin, bismaleimide / triazine resin, polyphenylene ether, polyacrylate, prepreg, film-like organic resin or a combination thereof.

13. The conductive substrate with filtering function according to claim 9, wherein the metal pillar comprises a hybrid metal that is etch-resistant and has low resistivity and high thermal conductivity.

14. A carrier board wiring structure, comprising a conductive substrate with filtering function as described in any one of claims 8 to 12.

15. The carrier board wiring structure according to claim 14 further includes a first circuit layer on the first side of the conductive substrate and a second circuit layer on the second side of the conductive substrate, wherein the first circuit layer and the second circuit layer are conductively connected through the first conductive post layer or the second conductive post layer.

16. The carrier board wiring structure according to claim 15 further includes a first augmentation layer on the first circuit layer, a first copper pillar layer within the first augmentation layer, a third circuit layer on the surface of the first augmentation layer, a third augmentation layer on the third circuit layer, a third copper pillar layer within the third augmentation layer, and a fifth circuit layer on the third augmentation layer, wherein the first circuit layer and the third circuit layer are electrically connected through the first copper pillar layer, and the third circuit layer and the fifth circuit layer are electrically connected through the third copper pillar layer.

17. The carrier board wiring structure according to claim 15 further includes a second layer on the second circuit layer, a second copper pillar layer within the second layer, a fourth circuit layer on the surface of the second layer, a fourth layer on the fourth circuit layer, a fourth copper pillar layer within the fourth layer, and a sixth circuit layer on the fourth layer, wherein the second circuit layer and the fourth circuit layer are electrically connected through the second copper pillar layer, and the fourth circuit layer and the sixth circuit layer are electrically connected through the fourth copper pillar layer.

Images