Anti-warping substrate core layer and anti-warping substrate
By embedding metal reinforced structures in the core layer of the substrate, the problem of warping of the substrate during packaging and reflow soldering is solved, the stability and reliability of the semiconductor package are improved, and the effect of simple structure and low cost is achieved.
Patent Information
- Application Number
- CN202421814390.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-29
- Publication Date
- 2025-06-03
- Estimated Expiration
- 2034-07-29
AI Technical Summary
In the prior art, the substrate is warped due to the mismatch of the thermal expansion coefficients of the material during the packaging and reflow soldering process, which in turn affects the electrical connection between the chip and the packaging substrate and reduces the stability and reliability of the product.
By embedding metal reinforcement structures in the core layer of the substrate, a composite material plate, a metal reinforcement structure and a copper foil structure are formed. The metal reinforcement structure is completely covered with the composite material plate and does not come into contact with the copper foil. The copper foil is arranged on the upper and lower surfaces of the composite material plate.
This structure can effectively suppress the warpage of the substrate during packaging and reflow soldering, improve the stability and reliability of semiconductor packaging, and has a simple structure and low cost, which is suitable for large-scale promotion and application.
Smart Images
Figure CN222939915U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of semiconductor packaging, and relates to a warp-resistant substrate core layer and a warp-resistant substrate. Background Art
[0002] The substrate plays a crucial role in the semiconductor field, providing mechanical support and electrical connection for electronic components. Substrates in the prior art typically include a core layer, a dielectric layer, and a conductive layer. Among them, the core layer is the support structure of the substrate, providing certain mechanical strength and stability for the substrate, and having a relatively large thickness. In addition, the substrate is composed of multiple composite materials, and the thermal expansion coefficients of various materials are also different. With the rapid development of technology in the semiconductor field, 2.5D / 3D stacked packaging has been widely adopted, and the size of the substrate has gradually increased.
[0003] However, during the operation process, especially during packaging and reflow soldering, temperature changes will occur. Due to the characteristic of the mismatch of the thermal expansion coefficients of materials in the multi-layer structure of the substrate, when the temperature rises, these materials will expand or contract at different rates, resulting in warping of the substrate at high temperatures, and then leading to the separation of the chip from the packaging substrate. This phenomenon is more obvious in large-size packaging substrates. The warping of the substrate will cause the electrical connection between the chip and the packaging substrate to fail, resulting in product scrapping and a decrease in yield.
[0004] Therefore, how to solve the warping problem of the substrate to improve the stability and reliability of semiconductor packaging has become an important problem that needs to be solved urgently by those skilled in the art. Summary of the Utility Model
[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present utility model is to provide a warp-resistant substrate core layer and a warp-resistant substrate, which are used to solve the problem of substrate warping caused by temperature changes during operations such as packaging or reflow soldering in the prior art.
[0006] To achieve the above purpose and other related purposes, the first aspect of the present utility model provides a warp-resistant substrate core layer, including a composite material plate, a metal reinforcement structure, and copper foil; the entire warp-resistant structure is completely coated in the composite material plate and does not contact the copper foil; the copper foil is disposed on the upper and lower surfaces of the composite material plate.
[0007] In one embodiment, the volume ratio of the metal reinforcement structure to the composite material plate is 1:(3 - 4).
[0008] In one embodiment, the metal reinforcement structure is centrosymmetric.
[0009] In one embodiment, the metal reinforcement structure is in a shape of a double square frame or a grid.
[0010] In one embodiment, the length and width of the copper foil are the same as those of the composite material board.
[0011] In one embodiment, the metal reinforcement structure is distributed near the edge of the composite material board.
[0012] In one embodiment, the metal reinforcement structure is centrosymmetrically distributed in the composite material board.
[0013] In one embodiment, the thickness ratio of the composite material board to the metal reinforcement structure is (2 - 4):1.
[0014] In one embodiment, the length of the substrate core layer is greater than or equal to 30 mm, and the width is greater than or equal to 15 mm.
[0015] In a second aspect of the present invention, there is provided a warpage-resistant substrate, which includes the warpage-resistant substrate core layer as described above.
[0016] As described above, the present invention provides a warpage-resistant substrate core layer and a warpage-resistant substrate. The warpage-resistant substrate core layer has a metal reinforcement structure. By embedding the metal reinforcement structure in the substrate core layer, the present invention further enhances the stability of the substrate core layer, and thus can strongly inhibit the warpage of the substrate during the processes of encapsulation and reflow soldering, thereby improving the stability and reliability of semiconductor encapsulation. Moreover, the warpage-resistant substrate core layer has a simple structure and low cost, and can be widely applied in the semiconductor field. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It shows a process flow chart of the warpage-resistant substrate core layer of the present invention.
[0018] Figure 2 It shows a top view of the warpage-resistant substrate core layer of the present invention.
[0019] Figure 3 It shows one of the cross-sectional views of the warpage-resistant substrate core layer of the present invention.
[0020] Figure 4 It shows another cross-sectional view of the warpage-resistant substrate core layer of the present invention.
[0021] Figure 5 It shows an exploded structural schematic diagram of the warpage-resistant substrate of the present invention.
[0022] DESCRIPTION OF REFERENCE NUMERALS
[0023] 100 Warpage-resistant substrate core layer
[0024] 101 Metal reinforcement structure
[0025] 102 Composite material board
[0026] 103 Wiring area
[0027] 104 Copper foil
[0028] 200 Conductive layer
[0029] 300 Dielectric layer
[0030] 400 Top solder mask layer
[0031] 500 Bottom solder mask layer Detailed implementation manners
[0032] The following uses specific specific examples to illustrate the implementation manners of the present utility model. Those skilled in the art can easily understand other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific implementation manners, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model.
[0033] Please refer to Figures 1 to 5 . It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present utility model in a schematic manner. Therefore, only the components related to the present utility model are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and ratios of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.
[0034] As Figure 1 and 2 shown, this embodiment provides a specific warp-resistant substrate core layer 100, including a composite material board 102, a metal reinforcement structure 101, and a copper foil 104; the metal reinforcement structure 101 is completely coated in the composite material board 102 and does not contact the copper foil 104; the copper foil 104 is provided on the upper and lower surfaces of the composite material board 102.
[0035] This application does not specifically limit the type of the composite material board 102, as long as it can be used in the substrate core layer in the prior art, including but not limited to the core layer of a printed circuit board (PCB) with metal wiring inside, the core layer of a through silicon via (TSV) with metal posts inside, or the core layer of a re-distribution layer (RDL) with metal wiring inside, etc.
[0036] Specifically, in one such asFigure 2 In a specific embodiment, the composite material board 102 is composed of a glass fiber cloth as a reinforcing material, a resin as an adhesive, and glass particles as a filler, and is used to form the core layer of a printed circuit board (PCB) with metal wirings inside. However, the type of the composite material board 102 is not limited thereto and can be selected according to needs.
[0037] Specifically, the material of the metal reinforcing structure 101 is selected from one or two of copper and stainless steel. In an Figure 2 embodiment, the material of the metal reinforcing structure 101 is copper.
[0038] Specifically, the volume ratio of the metal reinforcing structure 101 to the composite material board 102 is 1:(3 - 4).
[0039] As an example, the volume ratio of the metal reinforcing structure 101 to the composite material board 102 includes but is not limited to 1:3, 1:3.5, and 1:4. In an Figure 1 embodiment, the volume ratio of the metal reinforcing structure 101 to the composite material board 102 is 1:3. Thus, sufficient stress is provided for the warp-resistant substrate core layer 100 to avoid warping of the substrate core layer due to temperature changes during operation.
[0040] Specifically, the number of the metal reinforcing structures 101 is at least 1. As an example, it can be 1, 2, or 3. As shown in Figure 3 and 4 , the number of the metal reinforcing structures 101 is 1 or 2, and can be selected according to needs.
[0041] Specifically, in this application, the coating method of the metal reinforcing structure 101 is not specifically limited.
[0042] As an example, it can be coated on the upper surface or the lower surface or the center of the composite material board 102, or embedded in both the upper and lower surfaces at the same time. Specifically, in an Figure 3 embodiment, the metal reinforcing structure 101 is 1 and is coated in the center of the composite material board 102. Specifically, in another Figure 4 example, the metal reinforcing structures 101 are 2 and are respectively coated by the upper surface and the lower surface of the composite material board 102. Thus, strong support is provided for the substrate core layer 100.
[0043] As Figure 1 and 2As shown, in a specific embodiment, there is 1 metal reinforcement structure 101, and the metal reinforcement structure 101 is coated on the upper surface of the composite material plate 102.
[0044] As Figure 2 shown, the metal reinforcement structure 101 is centrosymmetric. Thus, the metal reinforcement structure 101 can evenly disperse the stress generated due to temperature changes, so that the substrate core layer 100 has the function of resisting warping.
[0045] Specifically, the metal reinforcement structure 101 is in a shape of a rectangle with a hole in the middle or a grid. In an embodiment such as Figure 1 and 2 shown, the metal reinforcement structure 101 is in a shape of a rectangle with a hole in the middle.
[0046] Specifically, the length and width of the copper foil 104 are the same as those of the composite material plate 102.
[0047] Specifically, the metal reinforcement structure 101 is distributed near the edge of the composite material plate 102. Setting the metal reinforcement structure 101 at the edge of the composite material plate 102 can improve the warping of the substrate core layer 100 to the greatest extent and further enhance the warping resistance function of the substrate core layer. In an embodiment such as Figure 2 shown, the length of the composite material plate 102 is 120 mm, the width is 60 mm, the outer frame length of the metal reinforcement structure 101 is 100 mm, the width is 55 mm, the inner frame length is 90 mm, and the width is 45 mm.
[0048] Specifically, the metal reinforcement structure 101 is centrosymmetrically distributed in the composite material plate 102. Thus, the metal reinforcement structure 101 can evenly disperse the stress generated due to temperature changes, so that the substrate core layer 100 has the function of resisting warping.
[0049] Specifically, a wiring area 103 is also provided on the copper foil 104, and the wiring area 103 refers to an area for arranging wires, circuit paths, and signal lines.
[0050] Specifically, the thickness ratio of the composite material plate 102 to the metal reinforcement structure 101 is (2 - 4):1. As an example, the thickness ratio of the composite material plate 102 to the metal reinforcement structure 101 includes but is not limited to 2:1, 3:1, 4:1. In an embodiment such as Figure 3 shown, the thickness ratio of the composite material plate 102 to the metal reinforcement structure 101 is 2:1.
[0051] As an example, the thickness of the composite material board 102 can be 400μm, 800μm, 1200μm, etc., and the thickness of the copper foil can be 12μm, 18μm, etc. Adjustment and selection can be made according to needs.
[0052] Specifically, the length of the substrate core layer 100 is greater than or equal to 30mm, and the width is greater than or equal to 15mm. For example, the length of the substrate core layer 100 includes but is not limited to 30mm, 50mm, 80mm, 100mm, 120mm; the width of the substrate core layer 100 includes but is not limited to 15mm, 20mm, 40mm, 60mm. In one Figure 2 illustrated embodiment, the length of the substrate core layer is 120mm and the width is 60mm.
[0053] As Figure 5 illustrated, this embodiment further provides a specific warpage-resistant substrate, and the warpage-resistant substrate contains the warpage-resistant substrate core layer 100 as described above.
[0054] Specifically, in one Figure 5 illustrated embodiment, the warpage-resistant substrate further has a dielectric layer 300, a conductive layer 200, a top solder mask layer 400, and a bottom solder mask layer 500.
[0055] Specifically, the top solder mask layer 400 is provided with one or two of chips and components. As an example, the components include at least one of resistors, inductors, and capacitors.
[0056] Specifically, the bottom solder mask layer 500 is provided with a plurality of solder balls.
[0057] Specifically, the upper and lower surfaces of the substrate core layer 100 are provided with a conductive layer 200; the conductive layer 200 and the dielectric layer 300 are alternately distributed in sequence; the lower surface of the top solder mask layer 400 is provided with a conductive layer 200; the upper surface of the bottom solder mask layer 500 is provided with a conductive layer 200.
[0058] As an example, the material of the conductive layer 200 includes copper foil.
[0059] As an example, the material of the dielectric layer 300 includes but is not limited to polyimide, ceramic, and epoxy resin.
[0060] During the actual operation process, due to the characteristic of mismatched coefficients of thermal expansion of materials in the multi-layer structure of the substrate, warping phenomena will basically occur when the temperature changes, especially severe warping of the core layer. The specific mechanism of this application to prevent warping by embedding a metal strengthening structure in the core is as follows: On the one hand, the metal strengthening structure can help disperse thermal stress, making the stress more evenly distributed across the entire substrate, thereby reducing the phenomenon of local stress concentration and minimizing warping deformation. On the other hand, the edges of the substrate are usually the areas most prone to warping. By embedding a metal strengthening structure at the edges, additional support can be provided to prevent the edges from warping. In addition, the metal strengthening structure also increases the structural rigidity of the core layer, effectively improving its flexural strength and torsional strength, thereby reducing the possibility of warping.
[0061] In summary, the present utility model provides an anti-warping substrate core layer and an anti-warping substrate. The anti-warping substrate core layer has a metal strengthening structure. By embedding a metal strengthening structure in the substrate core layer, the present utility model further enhances the stability of the substrate core layer, and thus can strongly inhibit warping during the processes of encapsulation and reflow soldering of the substrate. The effect is more obvious in large-size packaging substrates, effectively improving the stability and reliability of semiconductor packaging, avoiding excessive warping after encapsulation, damage to solder balls connecting chips and the substrate, and delamination between the encapsulation glue and the substrate, thereby improving the reliability and yield of the product. Moreover, the anti-warping substrate core layer has a simple structure and low cost, and can be widely promoted and applied in the semiconductor field. Therefore, the present utility model effectively overcomes various disadvantages in the prior art and has high industrial utilization value.
[0062] The above embodiments are only illustrative of the principles and effects of the present utility model, and are not used to limit the present utility model. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present utility model. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present utility model should still be covered by the claims of the present utility model.
Claims
1. A warping-resistant substrate core layer, characterized in that: It includes a composite material board (102), a metal reinforcement structure (101), and a copper foil (104); the metal reinforcement structure (101) is completely encapsulated in the composite material board (102) and does not contact the copper foil (104); the copper foil (104) is provided on the upper and lower surfaces of the composite material board (102).
2. The substrate core layer according to claim 1, characterized in that: The volume ratio of the metal reinforcement structure (101) to the composite material board (102) is 1:(3 - 4).
3. The substrate core layer according to claim 1, characterized in that: The metal reinforcement structure (101) is centrosymmetric.
4. The substrate core layer according to claim 1, characterized in that: The metal reinforcement structure (101) is in a zigzag or grid shape.
5. The substrate core layer according to claim 1, characterized in that: The length and width of the copper foil (104) are the same as those of the composite material board (102).
6. The substrate core layer according to claim 1, characterized in that: The metal reinforcement structure (101) is distributed near the edge of the composite material board (102).
7. The substrate core layer according to claim 3, characterized in that: The metal reinforcement structure (101) is centrosymmetrically distributed in the composite material board (102).
8. The substrate core layer according to claim 2, characterized in that: The thickness ratio of the composite material board (102) to the thickness of the metal reinforcement structure (101) is (2 - 4):
1.
9. The substrate core layer according to claim 1, characterized in that: The length of the substrate core layer (100) is greater than or equal to 30 mm, and the width is greater than or equal to 15 mm.
10. A warpage-resistant substrate, the warpage-resistant substrate includes the warpage-resistant substrate core layer (100) according to any one of claims 1 - 9.