Packaging substrate and pin-free packaging device

Abstract

The invention relates to the technical field of semiconductor packaging, and discloses a packaging substrate and a pin-free packaging device. The packaging substrate comprises a substrate main body, a first bonding pad group and a first exhaust groove, the first bonding pad group is arranged in a first target area on one side of the substrate main body, and the first bonding pad group comprises a plurality of first bonding pads which are arranged at intervals; the first exhaust grooves are at least formed in a first target area on one side of the substrate body and located between the adjacent first bonding pads. In the invention, the first bonding pad group arranged on the substrate main body is matched with the large-area heat-conducting bonding pad in the packaging element, so that the large-area heat-conducting bonding pad in the packaging element can be welded and fixed with the first bonding pad group; the first exhaust grooves are formed in the gap areas between the adjacent first bonding pads, so that the welding area of the first bonding pads and the to-be-mounted packaging element is not affected, gas generated in the welding process can be fully exhausted, welding holes are avoided, the welding quality is improved, and the reliability of the packaging element is finally realized.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor packaging, and in particular to a packaging substrate and a pinless packaging device. Background Art

[0002] Quad Flat No-leads Package (QFN) is a leadless surface mount package that is square or rectangular in shape. There is a large exposed pad at the center of the bottom of the package for heat conduction, and there are conductive pads around the package for electrical connection. The QFN package has good electrical and thermal performance, and is small and light, making it an ideal choice for many new applications and a hot topic in the industry.

[0003] The QFN package is mounted on the organic substrate through SMT. SMT (Surface Mount Technology) is a circuit assembly technology that mounts pinless or short-lead surface-mount components on the surface of an organic substrate and assembles them by soldering through reflow soldering. However, during the soldering process of the large-area thermal pads in the QFN packaged device to the organic substrate, the flux inside the printed solder paste will vaporize and volatilize during the heating process. The generated gas is difficult to completely discharge in the middle of the large-area welding surface, which can easily lead to welding voids, thereby affecting the reliability of the QFN packaged device. Summary of the invention

[0004] In view of this, the present invention provides a packaging substrate and a pinless packaging device to solve the problem that the gas generated during the welding process of the semiconductor packaging device is difficult to be completely discharged in the large area welding surface, which easily leads to welding voids and thus affects the reliability of the semiconductor packaging device.

[0005] In a first aspect, the present invention provides a packaging substrate, comprising: a substrate body, a first solder pad group and a first exhaust groove; the first solder pad group is arranged in a first target area on one side of the substrate body, and the first solder pad group includes a plurality of first solder pads arranged at intervals; the first exhaust groove is formed at least in the first target area on one side of the substrate body, and is located between adjacent first solder pads.

[0006] Beneficial effect: In the present invention, the area where the first pad group is located on the substrate body is suitable for matching with the large-area thermally conductive pad in the packaging component, so that the large-area thermally conductive pad in the QFN packaging component can be welded and fixed to the first pad group; a first exhaust groove with a certain depth is formed in the gap area between adjacent first pads, which will not affect the welding area between the first pad and the packaging component to be mounted, and can ensure that the gas generated during the welding process can be fully discharged, thereby avoiding the generation of welding voids, improving the welding quality, and finally realizing the reliable fixation of pinless packaging components with large-area thermally conductive pads such as QFN packaging components on the packaging substrate.

[0007] In an optional implementation, the plurality of first pads in the first pad group are arranged in a rectangular array.

[0008] Beneficial effect: Multiple first welding pads are arranged in a matrix, the overall welding force is uniform and stable, and the structure is simple, which helps to maximize the welding area in a limited area.

[0009] In an optional embodiment, the first exhaust groove is extended in a crisscross shape.

[0010] Beneficial effects: There are horizontal and vertical gap areas between the multiple first solder pads arranged in a matrix, and a first exhaust groove extending in a criss-cross shape is arranged in the gap area. The manufacturing process is simple and practical. An exhaust groove space is arranged between each adjacent first solder pad, which does not affect the effective welding area and can ensure the exhaust effect.

[0011] In an optional implementation, an isolation portion protruding from the surface of the substrate body is provided between adjacent first pads, and a first exhaust groove is formed in the isolation portion to isolate the first exhaust groove from the first pad.

[0012] Beneficial effects: an additional solder resist layer or an insulating material protruding from the surface of the substrate body is arranged between adjacent first pads, and a first exhaust groove is opened in the insulating material, and the first exhaust groove is relatively isolated from the window area of ​​the first pad on the horizontal plane; when each first pad is fixed to the large-area pad of the packaging component by solder paste, the flow of solder paste into the first exhaust groove can be reduced, thereby ensuring the smooth flow of the first exhaust groove space and the exhaust effect.

[0013] In an optional embodiment, there is a gap area between adjacent first pads, and a first exhaust groove is provided in the substrate body corresponding to the gap area, and the first exhaust groove is connected to at least a portion of the first pads.

[0014] Beneficial effects: a solder resist layer may be provided on the upper surface of the substrate body or insulating materials protruding from part of the substrate body, but these insulating materials do not completely isolate the first exhaust groove and the first pad window, and there is a partially connected gap space between the first exhaust groove and the first pad window area; or only a pad structure is provided on the surface of the substrate body, and no other protective layers such as insulating materials are provided, and a first exhaust groove is provided on the substrate body between a plurality of mutually spaced first pads, and the first exhaust groove penetrates deep into the substrate body, and when the large-area pad of the package component to be mounted is contacted and fixed with the first pad of the first pad group, the first exhaust groove with an extended space downward effectively enhances the exhaust space, thereby ensuring the exhaust effect; the first exhaust groove is connected to at least part of the first pad, which helps the welding gas generated at the first pad to smoothly enter the first exhaust groove, and the exhaust efficiency is high, and the package substrate structure is simple and easy to prepare.

[0015] In an optional embodiment, it also includes: a second pad group, which is arranged in a second target area on one side of the substrate body and is spaced apart from the first pad group; the number of second pad groups is the same as the number of sides of the substrate body; any second pad group includes a plurality of second pads spaced apart.

[0016] Beneficial effect: A second pad group is arranged in the second target area of ​​the substrate body for mounting module components, which is used for circuit connection with the components to be mounted, and the edge setting also facilitates electrical interconnection with structures in other functional areas on the packaging substrate, which helps to improve packaging integration.

[0017] In an optional embodiment, it also includes: a third pad group and a fourth pad group, which are arranged on a side surface of the substrate body away from the first pad group; the third pad group includes a plurality of third pads arranged at intervals, and the third pad group is arranged corresponding to the first pad group; the fourth pad group includes a plurality of fourth pads arranged at intervals, and the fourth pad group is arranged corresponding to the second pad group.

[0018] Beneficial effect: The first pad group and the second pad group are arranged on the top side of the substrate body, and the third pad group and the fourth pad group are arranged on the bottom side of the substrate body. The pads on the top side have the same structure as the pads on the bottom side, and correspond to each other up and down, which is convenient for efficient process, simplifies processing equipment, and is convenient for the package substrate to be installed on other components to achieve electrical interconnection.

[0019] In an optional embodiment, the substrate body includes:

[0020] Core layer;

[0021] A first substrate layer is arranged on one side surface of the core layer, and a first pad group and a second pad group are arranged on a side of the first substrate layer away from the core layer;

[0022] The second substrate layer is arranged on the other side of the core layer away from the first substrate layer; the third pad group and the fourth pad group are arranged on the side of the second substrate layer away from the core layer;

[0023] A via structure is provided, wherein the via structure penetrates the core layer, the first substrate layer and the second substrate layer, and the two ends are respectively connected to the first pad group and the third pad group; a conductive metal is formed on the inner wall surface of the via structure, one end of the conductive metal is connected to the first pad, and the other end is connected to the third pad.

[0024] Beneficial effect: The first substrate layer and the second substrate layer are respectively formed on both sides of the core layer for insulation protection, the first substrate layer is provided with a first pad group and a second pad group, and the second substrate layer is correspondingly provided with a third pad group and a fourth pad group, and a via structure with conductive metal is provided to penetrate the core layer, the first substrate layer and the second substrate layer, and connect the first pad group and the third pad group up and down to realize electrical connectivity on both sides of the packaging substrate.

[0025] In an optional implementation, it also includes:

[0026] A first solder resist layer is arranged on a side surface of the first substrate layer away from the core layer; the first solder resist layer is formed with a first opening and a second opening, the first opening correspondingly exposes the first pad group, and the second opening correspondingly exposes the second pad group; the first solder resist layer isolates adjacent first pads, and the first exhaust groove runs through the first solder resist layer between adjacent first pads;

[0027] The second solder resist layer is arranged on the side surface of the second base material layer away from the core layer; the second solder resist layer is formed with a third opening and a fourth opening, the third opening corresponds to exposing the third pad group, and the fourth opening corresponds to exposing the fourth pad group; the second solder resist layer isolates adjacent third pads, the second exhaust groove runs through the second solder resist layer between adjacent third pads, and the second exhaust groove is arranged corresponding to the first exhaust groove.

[0028] Beneficial effects: One side of the first substrate layer is also covered with a first solder resist layer, and one side of the second substrate layer is covered with a second solder resist layer. The first solder resist layer and the second solder resist layer are insulating ink protective layers, which isolate the welding part and the non-welding part on the top and bottom sides of the packaging substrate, and at the same time can protect the pad structure from oxidation; and the first exhaust hole is opened in the first solder resist layer, and the second exhaust hole is opened in the second solder resist layer, so as to avoid affecting the substrate body and the welding surface and ensure the performance of the packaging device.

[0029] In the second aspect, the present invention also provides a pinless packaging device, including: the above-mentioned packaging substrate, a pinless packaging component and a solder paste layer, the pinless packaging component is arranged on the packaging substrate; the pinless packaging component includes a thermally conductive pad and an insulating layer covering the thermally conductive pad, at least one end of the thermally conductive pad is exposed from the insulating layer, and the thermally conductive pad is connected to a first pad group; the solder paste layer is arranged between the first pad group and the thermally conductive pad, and the solder paste layer is arranged to protrude from the surface of the substrate body.

[0030] Beneficial effects: The pinless package component of the present invention can be a QFN package component, and the pinless package component includes a heat-conducting pad in the middle, a conductive pad at the edge, and an insulating layer wrapped on the outside, and the insulating layer insulates and protects the heat-conducting pad and the conductive pad as well as chips, and the heat-conducting pad and the conductive pad have exposed welding surfaces connected to the outside. During welding and fixing, the soldering layer is arranged between the pinless package component and the package substrate to achieve welding and fixing of the heat-conducting pad and the first pad group. At the same time, due to the existence of the soldering layer, a gap is formed between the pinless package component and the package substrate, which facilitates the gas in the first exhaust groove to be discharged to the external space, thereby reducing welding voids. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a top view schematic diagram of a packaging substrate in the related art;

[0033] Figure 2 is a top view schematic diagram of another packaging substrate in the related art;

[0034] Figure 3 is a schematic top view of a packaging substrate according to an embodiment of the present invention;

[0035] Figure 4 is a schematic top view of an organic substrate having a packaging substrate according to an embodiment of the present invention;

[0036] Figure 5 is based on Figure 3 A first cross-sectional schematic diagram of a package substrate cut along AA in the middle, with the first exhaust groove and the first pad being isolated and arranged;

[0037] Figure 6 is a second cross-sectional schematic diagram of a package substrate according to an embodiment of the present invention having a first exhaust groove and a first pad isolated from each other;

[0038] Figure 7 is a first cross-sectional schematic diagram of a package substrate according to an embodiment of the present invention having a first exhaust groove connected to a first pad;

[0039] Figure 8 is a second cross-sectional schematic diagram of a package substrate according to an embodiment of the present invention having a first exhaust groove connected to a first pad;

[0040] Fig. 9 Schematic diagram of the structure of a pinless packaging component according to an embodiment of the present invention.

[0041] Description of reference numerals:

[0042] B, organic substrate; a, central large pad; b, central pad group;

[0043] 100, packaging substrate; 200, pinless packaging component; 201, thermal pad; 202, insulation layer; 203, conductive pad;

[0044] 1. substrate body; 11. core layer; 12. first substrate layer; 13. second substrate layer; 14. via structure; 15. conductive metal;

[0045] 2. first pad group; 21. first pad;

[0046] 3. The first exhaust slot;

[0047] 4. second pad group; 41. second pad;

[0048] 5. third pad group; 51. third pad;

[0049] 6. Second exhaust slot;

[0050] 71. fourth pad;

[0051] 8. first solder resist layer; 81. first opening; 82. second opening;

[0052] 9. second solder resist layer; 91. third opening; 92. fourth opening. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only some structures related to the present invention are shown in the accompanying drawings, rather than all structures. In the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified for the purpose of clear expression, and some details may be omitted. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships between them are only exemplary, and may be deviated due to manufacturing tolerances or technical limitations in practice, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if one layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0054] In the related art, a package substrate for soldering and fixing a quad flat no-lead package (QFN) has a 3×3 mm large copper sheet full window, and the window area forms a large central pad a for heat conduction, such as Figure 1 As shown. When QFN package components are placed on an organic substrate by surface mounting or surface mounting technology (SMT), the leadless package components are first mounted on the substrate surface, and then soldered and assembled by reflow soldering or other methods. However, during the soldering and assembly process, the gas generated in the large soldering surface is difficult to be completely discharged, and bubbles are easily generated, resulting in voids, thereby affecting the reliability of the product. Furthermore, the central large solder pad a is separated into a matrix-type central solder pad group b, as shown in FIG. Figure 2 As shown, the problem of welding voids cannot be solved effectively.

[0055] Based on this, reference Figures 3 to 9 The present embodiment provides a packaging substrate 100, comprising: a substrate body 1, a first pad group 2 and a first exhaust groove 3; the first pad group 2 is arranged in a first target area on one side of the substrate body 1, and the first pad group 2 includes a plurality of first pads 21 arranged at intervals; the first exhaust groove 3 is at least formed in the first target area on one side of the substrate body 1, and is located between adjacent first pads 21.

[0056] See also Figure 4The above-mentioned packaging substrate 100 can be a functional area in a carrier such as an organic substrate B that realizes high-precision, high-sealing electrical connection between electronic components. The packaging substrate 100 of this embodiment is only for the area on the organic substrate B where one of the components of the module is mounted. Other areas on the organic substrate B include circuit interconnection areas, other component mounting areas, etc. Specifically, a first pad group 2 is arranged in a first target area on one side surface of the substrate body 1, and the first pad group 2 includes a plurality of first pads 21 arranged at intervals. The first pads 21 are made of metal materials with excellent conductive properties such as copper. The size and shape of the plurality of first pads 21 are not limited. For example, the first target area can be the middle area of ​​the substrate body 1. The middle area here is not strictly limited to an area with equal distances to the two opposite sides of the substrate body, and there can also be a partial offset, as long as the area where the first pad group 2 is located matches the large-area thermal conductive pad 201 in the package component, so that the large-area thermal conductive pad 201 in the QFN package component can be welded and fixed to the first pad group 2. In this embodiment, a first exhaust groove 3 with a certain depth is formed between adjacent first pads 21, which will not affect the welding area between the first pad 21 and the package component to be mounted, and can ensure that the gas generated during the welding process can be fully discharged, thereby avoiding the generation of welding voids, improving the welding quality, and finally realizing the reliable fixation of the leadless package component 200 with a large-area thermal conductive pad 201 such as QFN on the package substrate 100.

[0057] In one embodiment, see Figure 3 , the multiple first pads 21 in the first pad group 2 are arranged in a rectangular array.

[0058] The first soldering pad 21 in this embodiment is a square soldering pad, which has a regular shape and is easy to process and weld. Multiple square first soldering pads 21 are arranged in a matrix, and the overall welding force is uniform and stable, and the structure is simple, which helps to maximize the welding area in a limited area.

[0059] Of course, the first pad 21 may also be a circular pad, an island pad, a teardrop pad, a polygonal pad, an elliptical pad or other pads of special shapes. Among them, the circular pad can evenly distribute the thermal stress during welding, reduce the generation of welding cracks, and improve the reliability of welding; the elliptical pad has enough area to enhance the anti-peeling ability, so the circular pad and the elliptical pad can also be used as the preferred pad type.

[0060] On the basis of the above solution, the first exhaust groove 3 is extended in a crisscross shape.

[0061] Correspondingly, there are horizontal and vertical gap areas between the multiple first solder pads 21 arranged in a matrix, and a first exhaust groove 3 extending in a criss-cross shape is arranged in the gap area. The manufacturing process is simple and practical. An exhaust groove space is arranged between each adjacent first solder pad 21, which does not affect the effective welding area and can ensure the exhaust effect.

[0062] In addition, in the present embodiment, the first exhaust groove 3 is arranged to extend only to the edge of the first pad group 2, that is, the end of the first exhaust groove 3 is aligned with the end of the first pad group 2, which ensures the exhaust effect while improving the surface aesthetics of the packaging substrate 100, and at the same time avoids external impurities from entering the first exhaust groove 3 to affect the performance of the packaging components and the packaging substrate 100, thereby ensuring the reliability of the packaging device.

[0063] In an optional implementation, an isolation portion protruding from the surface of the substrate body 1 is provided between adjacent first pads 21 , and the first exhaust groove 3 is formed in the isolation portion to isolate the first exhaust groove 3 from the first pad 21 .

[0064] The isolation portion between adjacent first pads 21 protrudes from the surface of the substrate body 1. The isolation portion may be as follows: Figure 5 The additional insulating material such as the first solder resist layer shown in the figure may also be Figure 6 The structure formed by the upward protrusion of the substrate main body 1 of the shown part, the first exhaust groove 3 is opened in the isolation part, and the first exhaust groove 3 is relatively isolated from the window area of ​​the first solder pad 21 on the horizontal plane. There is no specific restriction on the width of the first exhaust groove 3, which can be set according to the gap size between the specific first solder pads 21, and has strong flexibility. Under this structure, when each first solder pad 21 is fixed to the large-area solder pad of the packaging component through solder paste, it can reduce the flow of solder paste into the first exhaust groove 3, thereby ensuring the smoothness of the space of the first exhaust groove 3 and the exhaust effect.

[0065] In another optional embodiment, there is a gap area between adjacent first pads 21 , and the substrate body 1 corresponding to the gap area is provided with a first exhaust groove 3 , and the first exhaust groove 3 is connected to at least a portion of the first pad 21 .

[0066] That is, an isolation portion protruding from the surface of the substrate body 1 may be provided between adjacent first pads 21, and the isolation portion may be an additional insulating material such as a first solder resist layer, or may be a structure formed by a portion of the substrate body 1 protruding upward, but the isolation portion does not completely isolate all of the first exhaust grooves 3 and the first pad 21 windows, and there is a partially connected space between the first exhaust grooves 3 and the first pad 21 window areas, that is, the first pad 21 and the first exhaust groove 3 may be partially connected on the side, and the other part has a barrier formed by the isolation portion, such as Figure 7As shown; or the horizontal surface of one side of the substrate body 1 is only provided with a pad structure, and other structures such as a structural layer are not provided, and a first exhaust groove 3 is provided on the substrate body 1 between a plurality of mutually spaced first pads 21, and the first exhaust groove 3 penetrates into the substrate body 1, and when the large-area pad of the package component is in contact and fixed with the first pad 21 of the first pad group 2, the first exhaust groove 3 with an extended space downward effectively enhances the exhaust space, thereby ensuring the exhaust effect, such as Figure 8 As shown; the first exhaust groove 3 is connected to at least part of the first pad 21, which helps the welding gas generated at the first pad 21 to smoothly enter the first exhaust groove 3, with high exhaust efficiency, and the packaging substrate 100 has a simple structure and is easier to prepare.

[0067] like Figure 3 As shown, the packaging substrate 100 of this embodiment also includes a second solder pad group 4, which is arranged in a second target area on one side of the substrate body 1 and is spaced apart from the first solder pad group 2; the number of second solder pad groups 4 is the same as the number of sides of the substrate body 1; any second solder pad group 4 includes a plurality of second solder pads 41 spaced apart.

[0068] A second pad group 4 is provided in the second target area of ​​the substrate body 1 for mounting the module components, for circuit connection with the components to be mounted, and in this embodiment, the second target area is the edge area of ​​the substrate body 1, and the edge arrangement facilitates electrical interconnection with the structures of other functional areas on the package substrate 100, which helps to improve the package integration. In this embodiment, the surface of the substrate body 1 is arranged as a quadrilateral, and the second pad group 4 is arranged as four groups, and any second pad group 4 includes a plurality of first pads 21 arranged in sequence along the edge of the substrate body 1, so as to facilitate all-round reliable electrical interconnection.

[0069] The packaging substrate 100 of the present embodiment may be configured to have a single-sided pad structure or a double-sided pad structure.

[0070] In one embodiment, when the packaging substrate 100 is a double-sided pad structure, the above-mentioned packaging substrate 100 also includes: a third pad group 5 and a fourth pad group arranged on the side surface of the substrate body 1 away from the first pad group 2, the third pad group 5 includes a plurality of third pads 51 arranged at intervals, and the third pad group 5 is arranged corresponding to the first pad group 2; the fourth pad group includes a plurality of fourth pads 71 ​​arranged at intervals, and the fourth pad group is arranged corresponding to the second pad group 4.

[0071] See also Figures 5 to 8, the first pad group 2 and the second pad group 4 are arranged on the top side of the substrate body 1, and the third pad group 5 and the fourth pad group are arranged on the bottom side of the substrate body 1. In this embodiment, the pads on the top side have the same structure as the pads on the bottom side, and correspond to each other up and down, which is convenient for efficient process and simplifies processing equipment, and is convenient for the package substrate 100 to be installed on other components to achieve electrical interconnection. Specifically, the first pad group 2 corresponds to the third pad group 5 up and down, and their shapes and sizes are the same, that is, the projections of the first pad 21 and the third pad 51 on the substrate body 1 coincide; the second pad group 4 corresponds to the fourth pad group up and down, and their shapes and sizes are the same, that is, the projections of the second pad 41 and the fourth pad 71 on the substrate body 1 coincide.

[0072] In one embodiment, Figures 5 to 8 As shown, the above-mentioned substrate body 1 includes: a core layer 11, a first substrate layer 12, a second substrate layer 13 and a via structure 14; the first substrate layer 12 is arranged on one side surface of the core layer 11, and the first pad group 2 and the second pad group 4 are arranged on the side of the first substrate layer 12 away from the core layer 11; the second substrate layer 13 is arranged on the other side surface of the core layer 11 away from the first substrate layer 12, and the third pad group 5 and the fourth pad group are arranged on the side of the second substrate layer 13 away from the core layer 11; the via structure 14 runs through the core layer 11, the first substrate layer 12 and the second substrate layer 13, and the two ends are respectively connected to the first pad group 2 and the third pad group 5; the inner wall surface of the via structure 14 forms a conductive metal 15, one end of the conductive metal 15 is connected to the first pad 21, and the other end is connected to the third pad 51.

[0073] Specifically, the core layer 11 is mainly composed of copper foil, solid resin material and glass fiber, the solid resin material sandwiches and covers the glass fiber, copper foil is set on the upper and lower surfaces of the solid resin material, and the core layer 11 has a certain hardness and thickness, which serves as a basic component of the package substrate 100. The first substrate layer 12 and the second substrate layer 13 are both semi-solid sheets, composed of semi-solid resin material and glass fiber, the semi-solid resin material sandwiches and covers the glass fiber, and the two are combined together to play a filling and bonding role. The first substrate layer 12 and the second substrate layer 13 are formed on both sides of the core layer 11 for insulation protection, the first substrate layer 12 is provided with a first pad group 2 and a second pad group 4, and the second substrate layer 13 is correspondingly provided with a third pad group 5 and a fourth pad group, and a via structure 14 with a conductive metal 15 runs through the core layer 11, the first substrate layer 12 and the second substrate layer 13, so as to connect the first pad group 2 and the third pad group 5 from top to bottom. Of course, a vertically penetrating via structure 14 can also be set between the second pad group 4 and the fourth pad group to achieve electrical connection. The conductive metal 15 and the third solder pad 51 of this embodiment are made of the same metal material as the first solder pad 21. During the preparation process, a vertical through hole can be first formed at specific positions of the core layer 11, the first substrate layer 12 and the second substrate layer 13, and then the conductive metal 15 is formed on the inner wall of the through hole. Then, the first solder pad 21 and the second solder pad 41 are respectively formed on the surfaces of the first substrate layer 12 and the second substrate layer 13, which are integrally formed with the conductive metal 15. Of course, other conductive materials or insulating materials can also be filled in the through hole as long as the electrical connection between the upper and lower solder pads can be achieved.

[0074] Furthermore, if Figure 5 As shown, the packaging substrate 100 of this embodiment also includes a first solder resist layer 8 and a second solder resist layer 9. The first solder resist layer 8 is arranged on a side surface of the first base material layer 12 away from the core layer 11, and the first solder resist layer 8 is formed with a first opening 81 and a second opening 82. The first opening 81 corresponds to exposing the first pad group 2, and the second opening 82 corresponds to exposing the second pad group 4; the first exhaust groove 3 passes through a portion of the first solder resist layer 8 between adjacent first pads 21; the second solder resist layer 9 is arranged on a side surface of the second base material layer 13 away from the core layer 11, and the second solder resist layer 9 is formed with a third opening 91 and a fourth opening 92, the third opening 91 corresponds to exposing the third pad group 5, and the fourth opening 92 corresponds to exposing the fourth pad group; the second exhaust groove 6 passes through a portion of the second solder resist layer 9 between adjacent third pads 51, and the second exhaust groove 6 is arranged corresponding to the first exhaust groove 3.

[0075] Specifically, a first solder resist layer 8 is also covered on one side of the first substrate layer 12, and a second solder resist layer 9 is covered on one side of the second substrate layer 13. The first solder resist layer 8 and the second solder resist layer 9 are insulating ink protective layers, which isolate the welding part and the non-welding part on the top and bottom sides of the package substrate 100, and can also protect the pad structure from oxidation. In this embodiment, green oil is selected. On the top side of the substrate body 1, the first solder resist layer 8 has a plurality of first openings 81 to expose a plurality of first pads 21 of the first pad group 2, forming a first pad 21 window. In addition, the first exhaust groove 3 runs through the first solder resist layer 8 between the first adjacent pads 21. In other embodiments, it can also be appropriately deep into the first substrate layer 12; the first solder resist layer 8 also has a plurality of second openings 82 to expose a plurality of second pads 41 of the second pad group 4, forming a second pad 41 window. Similarly, on one side of the bottom surface of the substrate main body 1, the second solder resist layer 9 opens a plurality of third openings 91 to expose a plurality of third solder pads 51 of the third solder pad group 5, forming windows for the third solder pads 51; the second solder resist layer 9 also opens a plurality of fourth openings 92 to expose a plurality of fourth solder pads 71 ​​of the fourth solder pad group, forming windows for the fourth solder pads 71; correspondingly, the second exhaust groove 6 passes through the second solder resist layer 9 between adjacent third solder pads 51, and in other embodiments, it may also appropriately penetrate into the second substrate layer 13.

[0076] refer to Figures 3 to 9 The present embodiment also provides a pinless packaging device, comprising: the above-mentioned packaging substrate 100, a pinless packaging component 200 and a solder paste layer, the pinless packaging component 200 is arranged on the packaging substrate 100, the pinless packaging component 200 includes a thermal conductive pad 201 and an insulating layer 202 coated outside the thermal conductive pad 201, at least one end of the thermal conductive pad 201 is exposed from the insulating layer 202, and the thermal conductive pad 201 is connected to the first pad group 2; the solder paste layer is arranged between the first pad group 2 and the thermal conductive pad 201, and the solder paste layer is arranged protruding from the surface of the substrate body 1.

[0077] The leadless package component 200 of this embodiment may be a QFN package component, such as Fig. 9As shown, the pinless package component 200 includes a heat-conducting pad 201 in the middle, a conductive pad 203 at the edge, and an insulating layer 202 wrapped on the outside. The insulating layer 202 insulates and protects the heat-conducting pad 201 and the conductive pad 203 as well as chips, etc. The heat-conducting pad 201 and the conductive pad 203 have exposed welding surfaces connected to the outside. The soldering layer is solder paste. When welding and fixing, the soldering layer is arranged between the pinless package component 200 and the package substrate 100 to achieve welding and fixing of the heat-conducting pad 201 and the first pad group 2. At the same time, due to the existence of the soldering layer, a gap is formed between the pinless package component 200 and the package substrate 100, which facilitates the gas in the first exhaust groove 3 to be discharged to the external space, thereby reducing welding voids.

[0078] The process of fixing the above-mentioned pinless package device on the package substrate 100 includes: first, setting a soldering layer on the first solder pad 21 and the second solder pad 41 on one side of the top surface of the package substrate 100; then, using tools such as tweezers to clamp the pinless package component 200 so that the side with the thermal conductive pad 201 is opposite to the package substrate 100, and dip the soldering layer material on the side surface of the pinless package component 200 with the thermal conductive pad 201; then, placing the pinless package component 200 on the package substrate 100, roughly aligning it with the area where the first solder pad group 2 is located; then, using an air gun welding tool, after adjusting the air gun temperature and wind speed to be appropriate, first tilt the air gun outlet to align it with the side of the pinless package component 200, and then vertically align it with the upper surface of the pinless package component 200, complete the melting of the soldering layer, and fix the pinless package component 200 on the package substrate 100 under the action of liquid tension.

[0079] The further functional description of each of the above structures is the same as that of the above corresponding embodiments and will not be repeated here.

[0080] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0081] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A packaging substrate, characterized in that: include: substrate body; A first pad group is arranged in a first target area on one side of the substrate body; the first pad group includes a plurality of first pads arranged at intervals; The first exhaust groove is formed at least in a first target area on one side of the substrate body and is located between adjacent first pads.

2. The packaging substrate according to claim 1, characterized in that: The plurality of first pads in the first pad group are arranged in a rectangular array.

3. The packaging substrate according to claim 2, characterized in that: The first exhaust groove is extended in a well shape.

4. The packaging substrate according to claim 3, characterized in that: An isolation portion protruding from the surface of the substrate body is provided between adjacent first pads, and the first exhaust groove is formed in the isolation portion to isolate the first exhaust groove from the first pad.

5. The packaging substrate according to claim 3, characterized in that: There is a gap area between adjacent first pads, and the first exhaust groove is provided in the substrate body corresponding to the gap area, and the first exhaust groove is connected with at least a part of the first pad.

6. The packaging substrate according to any one of claims 1 to 5, characterized in that: Also includes: The second pad group is arranged in the second target area on one side of the substrate body and is spaced apart from the first pad group; the number of the second pad groups is the same as the number of sides of the substrate body; any second pad group includes a plurality of second pads spaced apart.

7. The packaging substrate according to claim 6, characterized in that: Also includes: The third pad group and the fourth pad group are arranged on the side surface of the substrate body away from the first pad group; the third pad group includes a plurality of third pads arranged at intervals, and the third pad group is arranged corresponding to the first pad group; the fourth pad group includes a plurality of fourth pads arranged at intervals, and the fourth pad group is arranged corresponding to the second pad group.

8. The packaging substrate according to claim 7, characterized in that: The substrate body comprises: Core layer; A first substrate layer is disposed on one side of the core layer, and the first pad group and the second pad group are disposed on a side of the first substrate layer away from the core layer; A second substrate layer is arranged on the other side of the core layer away from the first substrate layer; the third pad group and the fourth pad group are arranged on the side of the second substrate layer away from the core layer; A via structure, wherein the via structure passes through the core layer, the first substrate layer and the second substrate layer, and the two ends are respectively connected to the first pad group and the third pad group; a conductive metal is formed on the inner wall surface of the via structure, one end of the conductive metal is connected to the first pad, and the other end is connected to the third pad.

9. The packaging substrate according to claim 8, characterized in that: Also includes: A first solder resist layer is arranged on a surface of the first substrate layer facing away from the core layer; The first solder resist layer is formed with a first opening and a second opening, the first opening correspondingly exposes the first pad group, and the second opening correspondingly exposes the second pad group; The first solder resist layer isolates the adjacent first pads, and the first exhaust groove penetrates the first solder resist layer between the adjacent first pads; A second solder resist layer is disposed on a surface of the second substrate layer facing away from the core layer; The second solder resist layer is formed with a third opening and a fourth opening, the third opening corresponds to exposing the third pad group, and the fourth opening corresponds to exposing the fourth pad group; the second solder resist layer isolates adjacent third pads, and a second exhaust groove penetrates the second solder resist layer between adjacent third pads, and the second exhaust groove is arranged corresponding to the first exhaust groove.

10. A leadless package device, characterized in that: include: The packaging substrate according to any one of claims 1 to 9; A pinless packaging component is arranged on the packaging substrate; The pinless package component comprises a thermally conductive pad and an insulating layer covering the thermally conductive pad, at least one end of the thermally conductive pad is exposed from the insulating layer, and the thermally conductive pad is connected to the first pad group; The soldering layer is arranged between the first pad group and the thermal conductive pad, and the soldering layer is arranged to protrude from the surface of the substrate body.

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