Frame layer manufacturing method, frame layer, embedded packaging substrate and circuit board

Abstract

The invention discloses a manufacturing method of a frame layer, the frame layer, an embedded packaging substrate and a circuit board, and relates to the technical field of substrate manufacturing, and the method comprises the steps: selecting a metal plate as a core plate of the frame layer, manufacturing a pattern on a first surface of the core plate, and then pressing a prepreg and a metal layer on the first surface, manufacturing the same pattern on the second surface of the core plate, then laminating a prepreg and a metal layer on the second surface on which the pattern is newly manufactured to obtain a semi-finished product frame layer, then processing blind holes in the front and back surfaces of the semi-finished product frame layer respectively, and electroplating the blind holes to obtain the semi-finished product frame layer. And the electroplated blind hole can be conducted with the non-insulating region of the core plate, so that the conduction between the two surfaces of the semi-finished product frame layer is realized. And finally, in the surface mounting process, performing groove milling and device embedding on the semi-finished product frame layer with the two sides being conducted to obtain the frame layer. The metal plate is utilized to provide better heat dissipation performance, and the process is simple and convenient to implement, so that the processing cost is reduced on the whole.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of substrate manufacturing, in particular to a frame layer manufacturing method, a frame layer, a buried packaging substrate and a circuit board. BACKGROUND

[0002] The buried packaging process refers to a substrate manufacturing process in which components and devices are directly buried in the substrate. The buried devices will inevitably generate heat during operation, and therefore the substrate carrying the devices needs to have certain heat dissipation performance. When the components and devices have large current transmission requirements, the heat dissipation performance of the substrate needs to be higher.

[0003] At present, the substrate carrying the devices mainly uses an organic frame, which is mainly filled with resin and glass fibers inside. Due to the limitation of the heat conduction performance of the organic material, the heat dissipation effect of the traditional organic frame is not high. In order to improve the heat dissipation effect of the organic frame, the metal content of the organic frame is usually improved by improving the processing technology of the substrate, such as X-hole filling process, pattern etching or thinning process, etc. However, the new process is relatively complex and not mature, and has a high risk, so it is easy to increase the processing cost. SUMMARY

[0004] Therefore, it is necessary to provide a frame layer manufacturing method, a frame layer, a buried packaging substrate and a circuit board to improve the heat dissipation performance of the frame layer at low cost in view of the above technical problems.

[0005] In a first aspect, a frame layer manufacturing method is provided, including: cutting a metal plate to obtain a core plate; performing pattern manufacturing on a first surface of the core plate according to a target pattern, the pattern manufactured on the first surface including a first metal removal area; pressing a prepreg and a metal layer on the first surface after pattern manufacturing; performing pattern manufacturing on a second surface of the core plate according to the target pattern, the pattern manufactured on the second surface including a second metal removal area; the second metal removal area being in communication with the corresponding first metal removal area to form an insulating area penetrating through the core plate; pressing a prepreg and a metal layer on the second surface after pattern manufacturing to obtain a semi-finished frame layer; machining blind holes on the front and back surfaces of the semi-finished frame layer respectively, and electroplating the blind holes to conduct the front and back surfaces of the semi-finished frame layer and the non-insulating area of the core plate through the electroplated blind holes; in a mounting process, milling grooves and burying devices on the semi-finished frame layer to obtain a frame layer.

[0006] In the embodiments of the present application, the metal plate is a copper plate, and / or the metal layer is a copper layer.

[0007] In the embodiments of the present application, the difference between the thickness of the device and the thickness of the metal plate is 20-30 μm.

[0008] In an embodiment of the present application, blind holes are respectively processed on the front and back sides of the semi-finished frame layer, and the blind holes are electroplated to connect the front and back sides of the semi-finished frame layer and the non-insulating area of ​​the core board through the electroplated blind holes, including: laser drilling is respectively performed at the same position on the front and back sides to process the blind holes, and the bottom of the blind hole is in contact with the non-insulating area of ​​the inner core board; copper is deposited on the hole wall of the blind hole by using a leveling hole process; and the blind hole after copper is deposited on the hole wall is electroplated to connect the two sides of the semi-finished frame layer and the non-insulating area of ​​the inner core board through the electroplated blind hole.

[0009] In an embodiment of the present application, blind holes are respectively processed on the front and back sides of the semi-finished frame layer, and the blind holes are electroplated so that the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the core board are connected through the electroplated blind holes. The method also includes: processing the same circuit patterns on the front and back sides of the semi-finished frame layer so that the circuits on the front and back sides are connected through the electroplated blind holes, and the blind holes are blind holes correspondingly arranged on the front and back sides.

[0010] In an embodiment of the present application, before laminating the semi-cured sheet and the metal layer on the first surface after the pattern is produced, the method further includes: performing a browning treatment on the first surface; and / or; before laminating the semi-cured sheet and the metal layer on the second surface after the pattern is produced, the method further includes: performing a browning treatment on the second surface.

[0011] In an embodiment of the present application, the pattern production on the first surface according to the target pattern includes: pasting a dry film on the first surface; producing an exposure film according to the target pattern; the exposure film is used to block the area where metal needs to be retained and expose the area where metal needs to be removed; superimposing the exposure film on the dry film and exposing the core board; removing the exposure film after exposure, and performing development, etching and stripping processes on the core board in sequence to complete the pattern production on the first surface; and / or; the pattern production on the second surface according to the target pattern includes: pasting a dry film on the second surface; superimposing the exposure film on the dry film and exposing the core board; removing the exposure film after exposure, and performing development, etching and stripping processes on the core board in sequence to complete the pattern production on the second surface.

[0012] In a second aspect, a frame layer is proposed, which is obtained according to the manufacturing method of the frame layer described in the first aspect.

[0013] In a third aspect, an embedded packaging substrate is provided, wherein the embedded packaging substrate includes the frame layer described in the second aspect.

[0014] In a fourth aspect, a printed circuit board is provided, wherein the printed circuit board includes the embedded package substrate described in the third aspect.

[0015] In any of the solutions provided above, a metal plate is selected as the core plate of the frame layer. Compared with the use of double-sided copper clad laminates in the prior art, the present application can increase the content of metals with higher thermal conductivity in the core plate. Then, a pattern is first made on the first surface of the core plate. After the pattern is made, a first metal removal area is formed on the first surface. Then, a semi-cured sheet and a metal layer are pressed on the first surface, so that the semi-cured material will be filled into the first metal removal area, as well as between the core plate and the metal layer, thereby ensuring the overall rigidity of the metal plate and avoiding deformation during subsequent processing. Then, the same pattern is made on the second surface of the core board, so that the first metal removal area processed on the first surface and the second metal removal area processed on the second surface can be connected up and down, thereby forming an insulating area in which no metal exists in the core board, and then the semi-cured sheet and the metal layer are pressed on the second surface of the newly completed pattern to obtain a semi-finished frame layer, thereby further improving the overall rigidity of the semi-finished frame layer, and at the same time, the insulating area of ​​the core board can be completely filled with semi-cured material, so that multiple insulating areas can be used to isolate multiple mutually insulated conductive areas in the inner core board, that is, non-insulating areas, to avoid the occurrence of short circuits in the entire board, and then blind holes are processed on the front and back sides of the semi-finished frame layer respectively, and the blind holes are electroplated so that the electroplated blind holes can be connected to the non-insulating area of ​​the core board, thereby achieving conduction between the two sides of the semi-finished frame layer. Finally, in the mounting process, the semi-finished frame layer that can be conductive on both sides is milled and the device is embedded to obtain the final frame layer. In the process of making the frame layer, the pattern production process, lamination process, blind hole processing process, slot milling and device embedding process used in this application are all traditional processes, mature and easy to operate. In addition, this application uses a metal plate as the core plate of the frame layer, so that the embedded devices can use the complete pure metal block around the device for heat transfer. Compared with double-sided copper clad laminates with a large amount of resin stacked in the middle layer, the frame layer made by this application can provide better heat dissipation performance. The process is simple and easy to implement, which can reduce the risk of scrapping, thereby reducing the overall processing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is a flow chart of a method for manufacturing a frame layer according to an exemplary embodiment of the present application; Figure 2 A cross-sectional view of a core board after patterning the first surface is shown in an exemplary embodiment of the present application; Figure 3 For Figure 2 The cross-sectional view of the core board obtained after the prepreg and metal layer are pressed together; Figure 4 For Figure 3 A cross-sectional view of the panel obtained after patterning the second surface of the core panel of the panel; Figure 5 For Figure 4 The cross-sectional view of the plate obtained after the prepreg and metal layer are pressed together; Figure 6 For Figure 5 The cross-section of the semi-finished frame layer obtained after blind hole electroplating and patterning of the plate shown; Figure 7 This is a flow chart of a method for manufacturing a frame layer shown in another exemplary embodiment of the present application.

[0018] The reference numerals in the specification are as follows: 1. Core board; 11. First surface; 12. First metal removal area; 13. Second surface; 14. Second metal removal area; 2. Insulation layer; 3. Metal layer; 4. Blind hole. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0020] It should be understood that the embodiments set forth below represent the necessary information to enable those skilled in the art to implement the embodiments and to illustrate the best mode of implementing the embodiments. After reading the following description in light of the accompanying drawings, those skilled in the art will understand the concepts of the present disclosure and will recognize applications of these concepts not specifically mentioned herein. It should be understood that these concepts and applications fall within the scope of the present disclosure and the appended claims.

[0021] It should also be understood that the terms "upper", "lower", "left", "right", "front", "back", "bottom", "middle", "top", etc. may be used in this document to describe various elements, and the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, so these elements should not be restricted by these terms.

[0022] It is further understood that the terms “comprises” and “includes” when used in this document specify the presence of stated features, integers, steps, operations, components and / or devices, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, devices and / or groups thereof.

[0023] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that the terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0024] The method for making a frame layer proposed in the embodiment of the present application can be applied in the production process of an embedded packaging substrate to make a frame layer for the embedded packaging substrate. The current embedded packaging substrate mostly adopts an organic frame, that is, the frame layer is obtained by repeatedly pressing copper foil and semi-cured sheets. The interior of the semi-cured sheet is mainly filled with resin and glass fiber. Usually, the thermal conductivity of the semi-cured material is 1-7W / (mk), while the thermal conductivity of copper can reach 401W / (mk). Therefore, in the traditional organic frame, in order to ensure the heat dissipation effect of the frame layer, the copper content in the frame layer is usually increased by an X-hole filling process or a pattern or thinning process. However, the X-hole filling process is not mature and there is a risk of hole filling depression, and the pattern or thinning process needs to be repeated, and the process is complicated. These factors have increased the processing cost of the high heat dissipation performance frame layer.

[0025] To solve the above problems, an embodiment of the present application provides a method for manufacturing a frame layer, which reduces process complexity and improves the heat dissipation performance of the frame layer at a lower cost.

[0026] Figure 1 This is a flow chart of a method for manufacturing a frame layer according to an exemplary embodiment of the present application.

[0027] like Figure 1 As shown, the method for manufacturing the frame layer may include the following steps: S101, cutting the metal plate to obtain a core plate.

[0028] For example, the metal plate is cut out according to the required size and thickness. The metal plate can be a pure metal plate or a composite metal plate, which is not limited in this application.

[0029] In one example, the metal plate may be a copper plate. The thermal conductivity of copper at 20°C is 401W / (m·K), which is higher than most other metals such as gold, aluminum, and iron. The thermal conductivity of silver is higher than that of copper, but its cost is higher. Therefore, using a copper plate as the core plate 1 of the frame layer can better balance thermal conductivity and material cost.

[0030] In one example, the thickness of the metal plate can be determined based on the thickness of the components to be embedded in the frame layer and the thickness of the insulation layer 2 required to ensure the rigidity of the core board 1. The insulation layer 2 can be understood as a structural layer formed between the surface of the core board 1 and the metal layer 3 after the prepreg is pressed together.

[0031] The specific value of the thickness of the metal plate can be determined through multiple tests. It is necessary to ensure that the difference between the total thickness of the frame layer and the thickness of the device is within the preset range during the test. The preset range can be determined based on the thickness range that the glue filling process can support after the device is embedded, so as to avoid the height difference between the two being too large after the device is embedded in the frame layer, which is inconvenient for glue filling and fixing. After determining the total thickness of the frame layer, it is also possible to determine through experiments the maximum thickness of the metal plate and the maximum thickness of the insulating layer 2, while ensuring that the rigidity of the core board 1 meets the requirements after the single-sided graphics are produced and the semi-cured sheet is pressed.

[0032] In one example, the thickness of the metal plate can be calculated by subtracting 20-30 μm from the thickness of the device. This allows the thickness of the metal plate to be increased while ensuring the rigidity requirements of the core board 1 and without affecting subsequent processes such as glue filling. This increases the metal content in the frame layer, improving the thermal conductivity of the frame layer with a simple process.

[0033] S102 , performing pattern production on the first surface of the core board according to the target pattern, wherein the pattern produced on the first surface includes a first metal removal area.

[0034] For example, a target pattern may be used to indicate areas where metal should be removed and areas where metal should be retained.

[0035] For example, Figure 2 As shown, patterning is performed on the first surface 11 of the core board 1. The pattern produced on the first surface 11 includes a first metal-removed area 12. The depth of the first metal-removed area 12 is less than the thickness of the core board 1. In this way, after patterning, the various parts of the core board 1 can still be maintained as a whole without falling apart.

[0036] S103, laminating a prepreg and a metal layer on the first surface after patterning.

[0037] After the first surface 11 of the inner core board 1 is patterned, the prepreg and the metal layer 3 are laminated on the first surface 11 .

[0038] like Figure 3 As shown, after lamination, the semi-cured material will fill the first metal removal area 12 processed during the pattern making process, as well as between the metal layer 3 and the first surface 11 of the core board 1.

[0039] The semi-cured material has a strong bonding ability, thereby bonding the various parts of the core panel 1 together, and utilizing the glass fiber in the semi-cured material to enhance the overall rigidity of the core panel 1 .

[0040] The metal layer 3 may be a pure metal layer or a mixed metal layer, which is not limited in this application.

[0041] In one example, the metal layer 3 may be a copper layer, thereby improving the thermal conductivity of the frame layer at a lower cost.

[0042] S104 , patterning is performed on the second surface of the core board according to the target pattern; the pattern produced on the second surface includes a second metal removal area; and the second metal removal area is connected to the corresponding first metal removal area.

[0043] Similarly, patterning is performed on the second surface 13 of the core plate 1 according to the target pattern, thereby symmetrically processing the same pattern on the first surface 11 and the second surface 13 of the core plate 1. Through the two patterning processes, the first metal removal area 12 processed on the first surface 11 and the second metal removal area 14 processed on the second surface 13 can be connected vertically.

[0044] like Figure 4 As shown, the total depth of the first metal removal area 12 and the second metal area that can communicate with each other up and down is the thickness of the core board 1, thereby forming an insulating area in the core board 1 that can penetrate the core board 1 and cannot conduct electricity.

[0045] S105, laminating a prepreg and a metal layer on the second surface after patterning to obtain a semi-finished frame layer.

[0046] On the second surface 13 with the newly completed pattern, the prepreg and the metal layer 3 are pressed together. After pressing, the prepreg material will fill the second metal removal area 14 processed on the second surface 13 and the space between the core board 1 and the metal layer 3.

[0047] like Figure 5As shown, the insulating area in the core panel 1 is filled with semi-cured material. This not only achieves insulation between two adjacent conductive areas, but also bonds two adjacent metal blocks together, thereby utilizing the glass fiber in the semi-cured material to ensure the overall rigidity of the inner core panel 1.

[0048] S106, processing blind holes on both sides of the semi-finished frame layer, and electroplating the blind holes, so that the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the inner core board are connected through the electroplated blind holes.

[0049] For example, blind holes 4 may be processed on both the front and back sides of the semi-finished frame layer processed in step S105 , and each blind hole 4 penetrates deep into the core board 1 .

[0050] After the blind hole 4 is processed, the blind hole 4 is electroplated. Conductive material can be deposited in the blind hole 4 by electroplating. The conductive material deposited in the blind hole 4 is used to connect the surface metal layer 3 of the semi-finished frame layer and the non-insulated area of ​​the core board 1, thereby achieving conduction on both sides of the semi-finished frame layer.

[0051] The location where the blind hole processing is performed can be determined according to the design requirements of the substrate. For example, the blind hole 4 is processed at the location where the upper and lower surfaces need to be connected in the semi-finished frame layer.

[0052] In one example, when the front and back sides of the semi-finished frame layer need to be processed with the same circuit pattern, it can be determined that the positions of the blind holes opened on the front and back sides of the semi-finished frame layer are the same. In this case, after the above step S106, the same circuit pattern is further processed on the front and back sides of the semi-finished frame layer, so that the circuits on both sides are connected through the blind holes after electroplating. Figure 6 The frame layer shown has the same circuit pattern processed on both sides.

[0053] S107, in the mounting process, the semi-finished frame layer is milled and the components are embedded to obtain the frame layer.

[0054] When implementing device mounting, grooves are milled at the device embedding positions on the semi-finished frame layer, and the devices are embedded in the processed grooves. After the devices are embedded, subsequent processes such as filling with glue can be implemented to fix the embedded devices and finally obtain the frame layer.

[0055] In summary, the embodiment of the present application provides a method for manufacturing a frame layer, which selects a metal plate as the core plate of the frame layer. Compared with the use of double-sided copper clad plates in the prior art, the present application can increase the content of metals with higher thermal conductivity in the core plate. Then, a pattern is first made on the first surface of the core plate. After the pattern is made, a first metal removal area will be formed on the first surface. Then, a semi-cured sheet and a metal layer are pressed on the first surface, so that the semi-cured material will be filled in the first metal removal area, as well as between the core plate and the metal layer, thereby ensuring the overall rigidity of the metal plate and avoiding deformation during subsequent processing. Then, the same pattern is made on the second surface of the core board, so that the first metal removal area processed on the first surface and the second metal removal area processed on the second surface can be connected up and down, thereby forming an insulating area in which no metal exists in the core board, and then the semi-cured sheet and the metal layer are pressed on the second surface of the newly completed pattern to obtain a semi-finished frame layer, thereby further improving the overall rigidity of the semi-finished frame layer, and at the same time, the insulating area of ​​the core board can be completely filled with semi-cured material, so that multiple insulating areas can be used to isolate multiple mutually insulated conductive areas in the inner core board, that is, non-insulating areas, to avoid the occurrence of short circuits in the entire board, and then blind holes are processed on the front and back sides of the semi-finished frame layer respectively, and the blind holes are electroplated so that the electroplated blind holes can be connected to the non-insulating area of ​​the core board, thereby achieving conduction between the two sides of the semi-finished frame layer. Finally, in the mounting process, the semi-finished frame layer that can be conductive on both sides is milled and the device is embedded to obtain the final frame layer. In the process of making the frame layer, the pattern production process, lamination process, blind hole processing process, slot milling and device embedding process used in this application are all traditional processes, mature and easy to operate. In addition, this application uses a metal plate as the core plate of the frame layer, so that the embedded devices can use the complete pure metal block around the device for heat transfer. Compared with double-sided copper clad laminates with a large amount of resin stacked in the middle layer, the frame layer made by this application can provide better heat dissipation performance. The process is simple and easy to implement, which can reduce the risk of scrapping, thereby reducing the overall processing cost.

[0056] In one embodiment, if Figure 7 As shown, the above step S106 of "processing blind holes on both sides of the semi-finished frame layer, and electroplating the blind holes, so as to connect the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the inner core plate through the electroplated blind holes" includes: S701, laser drilling is performed at the same position on both the front and back sides to form blind holes, and the bottom of the blind hole contacts the non-insulating area of ​​the core board.

[0057] Axially arranged blind holes 4 are respectively processed on the front and back surfaces of the frame layer, wherein the axis is perpendicular to the front and back surfaces of the frame layer.

[0058] When processing blind holes, a laser drilling process is used to drill holes on both sides of the frame layer, and the holes are stopped after the holes are drilled down to the metal contact with the core board 1.

[0059] S702: Using the horizontal hole process, copper is deposited on the hole wall of the blind hole.

[0060] For example, the blind hole 4 hole wall can be pretreated to remove hole wall contaminants, roughen the insulating surface, and provide a clean, rough attachment base for copper deposition. Then, activation and sensitization treatments are performed to adsorb palladium catalysts on the hole wall to activate the chemical copper deposition reaction, and then a continuous conductive copper layer is formed on the hole wall by chemical plating.

[0061] S703, electroplating the blind holes after copper plating on the hole walls, so as to connect the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the core board through the electroplated blind holes.

[0062] The blind hole 4 after copper deposition is electroplated on the hole wall to increase the thickness of the copper layer, and the blind hole 4 is filled with copper material.

[0063] After the electroplating is completed, the blind holes 4 can connect the front and back sides of the semi-finished frame layer to the non-insulated area of ​​the core board 1, thereby achieving the connection between the front and back sides of the semi-finished frame layer.

[0064] In this embodiment, blind holes 4 with relative positions are processed on the front and back sides of the semi-finished frame layer. If the front and back sides are to be conductive, it is only necessary to use the blind holes 4 to connect each side to the core board 1. Therefore, it is only necessary to process blind holes that penetrate the surface metal layer 3 and the insulating layer 2, thereby improving the processing efficiency. Then, the horizontal hole process is used to first deposit copper on the hole wall in the blind hole. The horizontal hole process improves the uniformity of copper deposition in the blind hole through horizontal fluid control and precise catalytic deposition. On this basis, the copper layer is thickened by electroplating, thereby ensuring the conductivity of the blind hole after electroplating, and then ensuring the conductive effect on the front and back sides of the semi-finished frame layer.

[0065] In some embodiments, the process of producing a pattern on either the first surface 11 or the second surface 13 according to the target pattern may include the following steps: A dry film is pasted on the surface; an exposure film is prepared according to the target pattern; the exposure film is used to block the areas where the metal needs to be retained and expose the areas where the metal needs to be removed; then, the exposure film is superimposed on the dry film and the inner core board 1 is exposed; after exposure, the exposure film is removed and the inner core board 1 is sequentially developed, etched and stripped to complete the patterning of the surface.

[0066] Exemplarily, the dry film comprises a photosensitive material and a plastic film. When patterning the first surface 11, the dry film can be applied to the first surface 11, and then an exposure film can be superimposed on the dry film. During exposure, both the exposure film and the second surface 13 of the core board 1 are exposed to light. During the development phase, the dry film applied to the unexposed areas under the exposure film is removed using a developer. These areas are then etched to create the first metal removal area 12 on the first surface 11. Finally, the remaining dry film on the first surface 11 is removed.

[0067] The process of producing the pattern on the second surface 13 may refer to the above description of producing the pattern on the first surface 11 and will not be repeated here.

[0068] Based on the above embodiment, before the semi-cured sheet is pressed on any of the first surface 11 and the second surface 13, the surface can be browned to increase the roughness of the surface, thereby improving the bonding force between the insulating layer 2 obtained after pressing and the surface, thereby improving the rigidity of the core board 1.

[0069] In general, the method for making the frame layer provided by this application uses thick copper foil as the core board 1. Compared with the organic frame layer made based on the ordinary core board 1, the frame layer made by this application has a high copper content and better heat dissipation performance. Moreover, since the core board 1 of the frame layer itself is a conductor, there is no need to make through holes like the ordinary core board 1 and then electroplate the through holes to achieve conduction on both sides of the frame layer. This application directly processes blind holes in the outer layer to connect to the core board 1 and electroplates the blind holes, shortening the processing flow. The processing technology is simple and easy to operate, thereby reducing processing risks and overall processing costs.

[0070] The present application also proposes a frame layer, and the circuit board is obtained according to the method for manufacturing the frame layer described in any of the above embodiments.

[0071] It can be understood that based on the corresponding beneficial effects of the above embodiments, the frame layer of this embodiment is obtained based on the manufacturing method of the frame layer described in any of the above embodiments, and should also have corresponding technical effects. In order to avoid repetition, it will not be repeated here.

[0072] The present application also proposes an embedded packaging substrate, which includes the above-mentioned frame layer.

[0073] It can be understood that based on the corresponding beneficial effects of the above embodiments, the embedded packaging substrate of this embodiment includes the above frame layer, is processed on the basis of the above frame layer, and should also have corresponding technical effects. In order to avoid repetition, it will not be repeated here.

[0074] The present application also provides a printed circuit board, which includes the above-mentioned embedded packaging substrate.

[0075] It can be understood that based on the corresponding beneficial effects of the above embodiments, the printed circuit board of this embodiment includes the embedded packaging substrate described in the above embodiments, and should also have corresponding technical effects. In order to avoid repetition, it will not be described here.

[0076] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A method for manufacturing a frame layer, characterized in that: The method comprises: Cutting the metal plate to obtain a core plate; According to the target pattern, patterning is performed on the first surface of the core board, wherein the pattern produced on the first surface includes a first metal removal area; Laminating a prepreg and a metal layer on the first surface after pattern production; According to the target pattern, patterning is performed on the second surface of the core board, wherein the pattern produced on the second surface includes a second metal removal area; the second metal removal area is connected to the corresponding first metal removal area to form an insulating area penetrating the core board; Laminating a prepreg and a metal layer on the second surface after pattern production to obtain a semi-finished frame layer; Processing blind holes on both sides of the semi-finished frame layer, and electroplating the blind holes, so that the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the core board are connected through the electroplated blind holes; In the mounting process, the semi-finished frame layer is milled and components are embedded to obtain the frame layer.

2. The production method according to claim 1, characterized in that The metal plate is a copper plate, and / or the metal layer is a copper layer.

3. The production method according to claim 1, characterized in that The difference between the thickness of the device and the thickness of the metal plate is 20 μm to 30 μm.

4. The production method according to claim 1, characterized in that The method comprises: processing blind holes on the front and back sides of the semi-finished frame layer, and electroplating the blind holes so as to connect the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the core board through the electroplated blind holes, including: Laser drilling is performed at the same position on the front and back surfaces to form the blind holes, wherein the bottoms of the blind holes are in contact with the non-insulating area of ​​the inner core plate; Using a horizontal hole process, copper is deposited on the hole wall of the blind hole; The blind holes after copper plating are electroplated, so as to connect the two sides of the semi-finished frame layer and the non-insulated area of ​​the inner core board through the electroplated blind holes.

5. The production method according to claim 1, characterized in that: After machining blind holes on both sides of the semi-finished frame layer and electroplating the blind holes so as to connect the front and back sides of the semi-finished frame layer and the non-insulated area of ​​the core board through the electroplated blind holes, the method further comprises: The same circuit patterns are processed on both sides of the semi-finished frame layer, so that the circuits on both sides are connected through the blind holes after electroplating. The blind holes are blind holes correspondingly set on the front and back sides.

6. The manufacturing method according to claim 1, characterized in that Before laminating the prepreg and the metal layer on the first surface after the pattern is produced, the method further comprises: performing a browning treatment on the first surface; and / or; Before laminating the prepreg and the metal layer on the second surface after the pattern is formed, the method further includes: The second surface is subjected to a browning treatment.

7. The production method according to claim 1, characterized in that: The step of producing a pattern on the first surface according to the target pattern includes: adhering a dry film to the first surface; An exposure film is prepared according to the target pattern; the exposure film is used to block the area where the metal needs to be retained and expose the area where the metal needs to be removed; superimposing the exposure negative on the dry film and exposing the core board; After exposure, the exposure film is removed, and the core board is subjected to development, etching and film stripping processes in sequence to complete patterning of the first surface; and / or; The step of producing a pattern on the second surface according to the target pattern comprises: adhering a dry film to the second surface; superimposing the exposure negative on the dry film and exposing the core board; After exposure, the exposure film is removed, and the core board is subjected to development, etching and film stripping processes in sequence to complete the patterning of the second surface.

8. A frame layer, characterized in that: The frame layer is obtained according to the method for manufacturing the frame layer according to any one of claims 1 to 7.

9. A buried package substrate, characterized in that: The embedded package substrate includes the frame layer according to claim 8.

10. A printed circuit board, characterized in that: The printed circuit board includes the embedded package substrate according to claim 9.

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