Package substrate and preparation method thereof
By embedding I-shaped or C-shaped supports within the packaging substrate, the structural strength is enhanced, solving the warping and deformation problem of the packaging substrate during high-temperature processes, and enabling large-scale production and improved reliability of organic substrates.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG CHUANGHAO SEMICON CO LTD
- Filing Date
- 2026-02-04
- Publication Date
- 2026-05-15
AI Technical Summary
Existing packaging substrates are prone to warping and deformation due to thermal stress concentration during high-temperature packaging processes, leading to chip solder ball cracking and signal transmission failure. Furthermore, glass substrate preparation suffers from problems such as inclined channels, rough hole walls, easy peeling of copper layers, and difficulty in detecting microcracks, making it difficult to mass-produce.
An I-shaped or C-shaped support is embedded in the core board to form a packaging substrate. The support enhances the structure to resist warping and deformation. An organic substrate is used to replace the glass substrate, and the product is mass-produced in conjunction with existing production lines.
It effectively resists warping and deformation, avoids problems such as rough hole walls, tilted channels, and copper layer peeling, reduces production costs, improves testing reliability, and enables large-scale production.
Smart Images
Figure CN122055025A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of semiconductor packaging technology, and more specifically, to a packaging substrate and its preparation method. Background Technology
[0002] Currently, the packaging substrate is the connector between the chip and the external circuit. In high-temperature packaging processes, such as 260°C reflow soldering, the existing packaging substrate is prone to warping and deformation due to thermal stress concentration, which can lead to cracking of the chip's solder balls and ultimately signal transmission failure.
[0003] In related technologies, glass substrates are generally used as packaging substrates with reinforced structures, relying on the excellent dimensional stability and low coefficient of thermal expansion of glass materials to overcome the aforementioned warping and deformation defects.
[0004] The fabrication of glass substrates typically involves creating glass vias and electroplating copper onto the inner walls of these vias to achieve vertical interconnection between different layers. However, the following problems often arise during fabrication: When the aspect ratio of glass vias is too large, defects such as rough hole walls and tilted channels are prone to occur. The copper layer is easily peeled off from the inner wall of the glass via. The cost of glass substrates and their fabrication processes is much higher than that of organic substrates, making large-scale production difficult. Glass is brittle and prone to microcracks during fabrication. After lamination processing, the glass substrate is completely covered by organic and copper layers, which completely masks the internal microcracks, increasing the difficulty of detection and making it easy to miss detections. Glass substrates generally require specialized equipment for fabrication, requiring significant modifications to existing production lines and resulting in long lead times. Summary of the Invention
[0005] This application aims to at least partially solve one of the technical problems in the related art. To this end, embodiments of this application propose a packaging substrate and its preparation method, which can embed an I-shaped support or a C-shaped support into the core board, thereby enabling the manufactured packaging substrate to resist warping deformation during soldering. Therefore, a glass substrate is not used, thus avoiding the problems of channel tilting, rough hole walls, and easy copper layer peeling caused by glass substrates, as well as the problem of microcracks caused by the high brittleness of glass. Moreover, it can be mass-produced in conjunction with existing production lines.
[0006] The method for preparing the packaging substrate according to the embodiments of this application includes: A core board is provided, and a cavity is formed in the core board such that the cavity penetrates at least one surface of the core board along the thickness direction, forming an opening at the penetration point; A support body is embedded into the cavity through the opening; the support body includes an I-shaped support body or a C-shaped support body. An outer layer plate is provided on the side of the core plate located at the opening, so that the outer layer plate closes the cavity.
[0007] In some embodiments, the core board includes a first insulating layer and a first conductor layer disposed on both sides of the first insulating layer. The method of creating a cavity within the core board, such that the cavity penetrates at least one surface of the core board along its thickness direction, forming an opening at the penetration point, includes: A through hole is drilled in the first conductor layer using a mechanical drill bit, so that the through hole penetrates the first conductor layer along the thickness direction of the first conductor layer and forms the opening; A through groove is created in the first insulating layer by laser etching, so that the through groove penetrates the first insulating layer along the thickness direction of the first insulating layer, and the through groove communicates with the through hole to form the cavity.
[0008] In some embodiments, while creating a cavity in the core board, a first circuit pattern is formed on the first conductor layer.
[0009] In some embodiments, before embedding the support body into the cavity through the opening, the method further includes: providing an adhesive film on any surface of the core board, the adhesive film being used to seal one of the openings and support the support body.
[0010] In some embodiments, before the outer layer plate is disposed on the side of the core plate located at the opening, so that the outer layer plate closes the cavity, the method further includes: A colloid is filled into the cavity of the core board to fill the gap between the support and the inner wall of the cavity. The colloid is used to bond the support to the inner wall of the cavity.
[0011] In some embodiments, the outer layer includes a second insulating layer and a second conductor layer, and the fabrication method further includes: A via is formed in the second insulating layer and the second conductor layer, and a conductive layer is formed in the via, the conductive layer being connected to the first conductor layer; A second circuit pattern is formed on the second conductor layer.
[0012] The packaging substrate of this application embodiment is prepared by the preparation method described in any of the above embodiments.
[0013] In some embodiments, the packaging substrate includes: A core board, wherein a cavity is provided inside the core board, the cavity penetrates through both surfaces of the core board along the thickness direction, and forms an opening at the penetration point; A support body, which is embedded in the cavity through the opening, and the support body includes an I-shaped support body or a C-shaped support body; An outer layer plate is disposed on the side of the core plate located at the opening, for sealing the cavity.
[0014] In some embodiments, an adhesive is filled between the support and the inner wall of the cavity to bond the support and the inner wall of the cavity. The surface of the support is provided with grooves, and the adhesive can fill the grooves and bond with the support.
[0015] In some embodiments, the support is made of glass or diamond copper.
[0016] The packaging substrate fabrication method of this application embodiment involves creating a cavity within a core board and embedding a support within the cavity. The special shape of the support, either I-shaped or C-shaped, enhances the structure of the packaged substrate, thereby preventing warping during soldering. Furthermore, it avoids the problems associated with glass substrates, such as rough hole walls, tilted channels, and easy copper layer peeling, which are common when fabricating vias. The packaging substrate of this application can also be made of organic substrates, enabling large-scale production on existing production lines and avoiding the problem of microcracks caused by the brittleness of glass. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0018] Figure 1 This is a schematic flowchart of the method for preparing the packaging substrate according to an embodiment of this application.
[0019] Figure 2 This is a schematic diagram of the core board formed by the preparation method of this application embodiment.
[0020] Figure 3 This is a schematic diagram of the structure of forming through holes on the core board according to the preparation method of this application embodiment.
[0021] Figure 4 This is a schematic diagram of the cavity formed on the core board according to the preparation method of this application.
[0022] Figure 5 This is a schematic diagram of the structure of the adhesive film formed on the core board according to the preparation method of this application embodiment.
[0023] Figure 6 This is a schematic diagram of the structure of the support embedded in the cavity in the preparation method of this application embodiment.
[0024] Figure 7 This is a schematic diagram of the structure of the preparation method of this application, in which the cavity is filled with colloid.
[0025] Figure 8 This is a schematic diagram of the structure of the outer layer plate formed on the core plate according to the preparation method of this application embodiment.
[0026] Figure 9 This is a schematic diagram of the structure of forming vias and conductive layers on the outer layer plate according to the preparation method of this application embodiment.
[0027] Figure 10 This is a schematic diagram of the first structure of the support in the preparation method of this application embodiment.
[0028] Figure 11 This is a schematic diagram of the second structure of the support in the preparation method of this application embodiment.
[0029] Figure 12 This is a schematic diagram of the structure of a packaging substrate according to an embodiment of this application.
[0030] Figure label: 100. Packaging substrate; 10. Core board; 11. First insulating layer; 12. First conductor layer; 20. Cavity; 21. Through hole; 22. Through groove; 30. Support structure; 31. Trench; 40. Outer layer; 41. Second insulating layer; 42. Second conductor layer; 43. Via; 431. Conductive layer; 50. Adhesive film; 60. Colloids. Detailed Implementation
[0031] The embodiments of this application are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.
[0032] The following is combined Figures 1 to 12 This application describes the packaging substrate and its fabrication method according to embodiments of the present application.
[0033] refer to Figures 1 to 11 This application provides a method for preparing a packaging substrate, in which an I-shaped or C-shaped support is embedded in the core board 10, thereby enabling the prepared packaging substrate 100 to resist warping deformation during soldering. Furthermore, it avoids the problems of rough hole walls, tilted channels, and easy copper layer peeling associated with glass substrates when preparing through-holes 21. The packaging substrate 100 of this application can also be made of organic substrate, enabling large-scale production on existing production lines, and also avoids the problem of microcracks caused by the high brittleness of glass.
[0034] refer to Figures 1 to 11The method for preparing the packaging substrate includes the following steps: S1. Provide a core board 10 and open a cavity 20 in the core board 10, so that the cavity 20 penetrates at least one surface of the core board 10 along the thickness direction of the core board 10, and forms an opening at the penetration point.
[0035] S2. A support body 30 is embedded into the cavity 20 through the opening. The support body 30 includes an I-shaped support body or a C-shaped support body.
[0036] The shape of the cavity 20 matches the shape of the support 30, ensuring that the support 30 fits perfectly into the cavity 20.
[0037] S3. An outer layer plate 40 is provided on the side of the core plate 10 where the opening is located, so that the outer layer plate 40 closes the cavity 20.
[0038] The outer layer plate 40 seals the cavity 20 by closing the opening, ensuring the support 30 is embedded in the cavity 20 and preventing the support 30 from coming out.
[0039] The packaging substrate fabrication method of this application embodiment involves creating a cavity 20 within the core board 10 and embedding a support 30 within the cavity 20. The special shape of the I-shaped or C-shaped support enhances the structure of the fabricated packaging substrate 100, thereby preventing warping deformation during soldering. Furthermore, it avoids the problems of rough hole walls, tilted channels, and easy copper layer peeling associated with glass substrates when fabricating through-holes 21. The packaging substrate 100 of this application can also be made of organic substrates, enabling large-scale production on existing production lines and avoiding the problem of microcracks caused by the brittleness of glass.
[0040] refer to Figures 2 to 4 In some embodiments, the core board 10 includes a first insulating layer 11 and a first conductor layer 12 disposed on both sides of the first insulating layer 11. It is understood that there are two first conductor layers 12, respectively disposed on both sides of the first insulating layer 11.
[0041] In step S1, a cavity 20 is formed in the core board 10, such that the cavity 20 penetrates at least one surface of the core board 10 along the thickness direction of the core board 10, forming an opening at the penetration point. This includes the following steps: S11. A through hole 21 is drilled in the first conductor layer 12 using a mechanical drill bit, so that the through hole 21 penetrates the first conductor layer 12 along the thickness direction of the first conductor layer 12 and forms an opening.
[0042] S12. A through groove 22 is ablated into the first insulating layer 11 using laser etching, so that the through groove 22 penetrates the first insulating layer 11 along its thickness direction. The through groove 22 communicates with the through hole 21 and forms a cavity 20. It is understood that the through groove 22 and the through hole 21 are designed opposite each other along the thickness direction of the core board 10 to facilitate connection and communication. The cavity 20 is the space formed by the combination of the through groove 22 and the through hole 21.
[0043] The core board 10 can be a copper-clad laminate, which includes a substrate and copper layers covering both sides of the substrate. For example, the substrate can be FR4 (epoxy fiberglass) or other high-frequency substrates, which can be used to provide mechanical support. The first insulating layer 11 is the substrate, and the first conductor layer 12 is the copper layer.
[0044] By employing different drilling techniques, such as mechanical drilling and laser engraving, through holes 21 and through slots 22 are respectively formed in the first conductor layer 12 and the first insulating layer 11. This allows the different materials of the first conductor layer 12 and the first insulating layer 11 to be adapted to different drilling techniques, thus creating a match between the different drilling techniques and the different layers of the core board 10.
[0045] Continue to refer to Figure 3 In some embodiments, in step S1, while opening a cavity 20 in the core board 10, a first circuit pattern is formed on the first conductor layer 12.
[0046] A predetermined first circuit pattern can be formed on the first conductor layer 12 by chemical etching. The first circuit pattern is used to form a circuit layer with conductive function.
[0047] Continue to refer to Figure 5 In some embodiments, before embedding the support 30 into the cavity 20 through the opening in step S2, the following steps are also included: setting an adhesive film 50 on any surface of the core board 10, the adhesive film 50 being used to seal an opening and support the support 30.
[0048] The adhesive film 50 is a high-temperature resistant, low-residue adhesive film, which is adhered to the surface of the core board 10. The adhesive film 50 has a certain supporting effect and can prevent the support 30 from sliding out of the cavity 20.
[0049] Understandably, the adhesive film 50 needs to be removed before step S3 to prevent it from affecting the setting of the outer layer 40 on the core board 10.
[0050] Continue to refer to Figure 7 In some embodiments, before step S3, where an outer layer plate 40 is disposed on the side of the core plate 10 located at the opening, and the outer layer plate 40 closes the cavity 20, the following steps are also included: The cavity 20 of the core board 10 is filled with colloid 60, which fills the gap between the support 30 and the inner wall of the cavity 20. The colloid 60 is used to bond the support 30 to the inner wall of the cavity 20.
[0051] In this process, a vacuum press is used to press colloid 60 into the cavity 20 of the core board 10. The colloid 60 flows and compacts the gap between the support 30 and the inner wall of the cavity 20. The colloid 60 can be an epoxy resin insulating film (ABF) or pure glue.
[0052] It is worth noting that there is a 0.1mm capacity gap between the inner wall of the cavity 20 and each side of the support 30. This ensures a clearance fit between the support 30 and the cavity 20, facilitating the embedding of the support 30. The fluidized bed formed by the colloid 60 can penetrate into the gap, filling the space between the inner wall of the cavity 20 and the support 30, preventing the support 30 from shaking. At the same time, the colloid 60 can bond the support 30 to the inner wall of the cavity 20, thus fixing the support 30 within the cavity 20.
[0053] Continue to refer to Figure 8 and Figure 9 In some embodiments, the outer layer 40 includes a second insulating layer 41 and a second conductor layer 42, and the method for preparing the packaging substrate further includes: S4. A via 43 is formed in the second insulating layer 41 and the second conductor layer 42, and a conductive layer 431 is formed in the via 43. The conductive layer 431 is connected to the first conductor layer 12.
[0054] A uniform metal seed layer can be deposited on the inner wall of the via 43 by sputtering. The metal seed layer can be a thin copper or titanium copper layer. Then, a copper layer of a certain thickness is formed on the metal seed layer by electroplating, thereby forming a conductive layer 431 inside the via 43.
[0055] S5. A second circuit pattern is formed on the second conductor layer 42.
[0056] The second conductor layer 42 can be patterned using processes such as exposure and etching to form a preset second circuit pattern. The second circuit pattern is used to form a circuit layer with conductive functions.
[0057] In this embodiment, setting the outer layer plate 40 may specifically include: pressing a second insulating layer 41 onto one surface of the core plate 10. The second insulating layer 41 may be an epoxy resin insulating film (ABF). Subsequently, a second conductor layer 42 may be pressed onto the second insulating layer 41. The second conductor layer 42 may be a copper foil, such as an electrolytic copper foil.
[0058] This application also provides a packaging substrate 100, which is prepared by the packaging substrate preparation method in any of the above embodiments.
[0059] refer to Figures 1 to 11 In some embodiments, the encapsulation substrate 100 includes a core plate 10, a support 30, and an outer layer plate 40.
[0060] A cavity 20 is provided within the core board 10, extending through both surfaces of the core board 10 along its thickness direction and forming an opening at the penetration point. A support 30 is embedded within the cavity 20 through the opening, and the support 30 includes an I-shaped support or a C-shaped support. An outer layer plate 40 is disposed on the side of the core board 10 located at the opening, for sealing the cavity 20.
[0061] Understandably, there are two outer plates 40, which are respectively placed on the two surfaces of the core plate 10, thereby sealing both ends of the cavity 20.
[0062] The technical advantages of the packaging substrate 100 in this application embodiment are the same as those of the packaging substrate preparation method in the above embodiments, and will not be repeated here.
[0063] For details, please refer to the following: Figure 12 In some embodiments, the space between the support 30 and the inner wall of the cavity 20 is filled with colloid 60 to bond the support 30 and the inner wall of the cavity 20. The surface of the support 30 is provided with grooves 31, and the colloid 60 can be filled into the grooves 31 and bonded to the support 30.
[0064] The cross-section of the groove 31 is rectangular or trapezoidal.
[0065] The groove 31 provided on the surface of the support 30 can increase the bonding area between the support 30 and the colloid 60, thereby improving the bonding strength and tightness of the support 30 and the colloid 60.
[0066] refer to Figure 12 In some embodiments, the support 30 is made of glass or diamond copper.
[0067] Glass possesses high strength and low warpage. Diamond copper possesses high heat dissipation and low warpage. Both can be used as the support 30 to resist warpage deformation of the manufactured packaging substrate 100. In addition, diamond copper has good thermal conductivity and heat dissipation, which facilitates the formation of heat dissipation channels and accelerates the heat dissipation of power components within the manufactured packaging substrate 100.
[0068] refer to Figure 11 As a preferred solution, the support 30 is a C-shaped support made of diamond copper. This C-shaped support formed by the diamond copper creates a surrounding heat dissipation channel, resulting in better heat dissipation. This solution is suitable for high-end AI, automotive electronics, and other products.
[0069] refer to Figure 10As another preferred option, the support 30 is an I-shaped support made of glass. This type of glass support is easy to manufacture and has controllable costs. This solution is applicable to consumer electronics, conventional RF chips, and other products.
[0070] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0071] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0072] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present application.
Claims
1. A method for preparing a packaging substrate, characterized in that, include: A core board is provided, and a cavity is formed in the core board such that the cavity penetrates at least one surface of the core board along the thickness direction, forming an opening at the penetration point; A support body is embedded into the cavity through the opening; the support body includes an I-shaped support body or a C-shaped support body. An outer layer plate is provided on the side of the core plate located at the opening, so that the outer layer plate closes the cavity.
2. The preparation method according to claim 1, characterized in that, The core board includes a first insulating layer and a first conductor layer disposed on both sides of the first insulating layer. The method of creating a cavity within the core board, such that the cavity penetrates at least one surface of the core board along its thickness direction, forming an opening at the penetration point, includes: A through hole is drilled in the first conductor layer using a mechanical drill bit, so that the through hole penetrates the first conductor layer along the thickness direction of the first conductor layer and forms the opening; A through groove is created in the first insulating layer by laser etching, so that the through groove penetrates the first insulating layer along the thickness direction of the first insulating layer, and the through groove communicates with the through hole to form the cavity.
3. The preparation method according to claim 2, characterized in that, While creating a cavity within the core board, a first circuit pattern is formed on the first conductor layer.
4. The preparation method according to claim 2, characterized in that, Before embedding the support body into the cavity through the opening, the method further includes: setting an adhesive film on any surface of the core board, the adhesive film being used to seal one of the openings and support the support body.
5. The preparation method according to claim 1, characterized in that, Before the outer layer plate is disposed on the side of the core plate located at the opening, so that the outer layer plate closes the cavity, the method further includes: A colloid is filled into the cavity of the core board to fill the gap between the support and the inner wall of the cavity. The colloid is used to bond the support to the inner wall of the cavity.
6. The preparation method according to claim 2, characterized in that, The outer layer includes a second insulating layer and a second conductor layer, and the preparation method further includes: A via is formed in the second insulating layer and the second conductor layer, and a conductive layer is formed in the via, the conductive layer being connected to the first conductor layer; A second circuit pattern is formed on the second conductor layer.
7. A packaging substrate, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 6.
8. The packaging substrate according to claim 7, characterized in that, The packaging substrate includes: A core board, wherein a cavity is provided inside the core board, the cavity penetrates through both surfaces of the core board along the thickness direction, and forms an opening at the penetration point; A support body, which is embedded in the cavity through the opening, and the support body includes an I-shaped support body or a C-shaped support body; An outer layer plate is disposed on the side of the core plate located at the opening, for sealing the cavity.
9. The packaging substrate according to claim 8, characterized in that, The space between the support and the inner wall of the cavity is filled with an adhesive to bond the support to the inner wall of the cavity. The surface of the support has grooves, and the adhesive can fill the grooves and bond with the support.
10. The packaging substrate according to claim 8, characterized in that, The support is made of glass or diamond copper.