A substrate structure for chip packaging

Abstract

This invention discloses a substrate structure for chip packaging, comprising a lower substrate, a chip, and gold wires, one end of which is connected to the chip. A chip slot is formed within the lower substrate, and a chip base is positioned at the center of the chip slot, on which the chip is placed. Multiple wire grooves are arranged within the chip slot, located between the sidewall of the chip slot and the chip base. The wire grooves are bent and folded along the bottom plane of the chip slot, and have at least one bend. Each end of the wire groove has an opening, and the gold wire is installed within the wire groove, with both ends extending from the two openings respectively. In this invention, the gold wire is laid along the trajectory of the wire groove, entering from one opening and exiting from the other opening after a bend. The bend restricts the freedom of the gold wire. After the gold wire connection is completed, molding is performed. Because the gold wire is physically constrained and partially covered by the wire grooves, it is less prone to displacement or deformation when impacted by the mold fluid during injection molding.

Description

Technical Field

[0001] This utility model relates to chip packaging, specifically to a substrate structure for chip packaging. Background Technology

[0002] In the semiconductor manufacturing process, chip packaging is a crucial step involving the dicing of finished wafers into individual bare chips, followed by the mounting of these chips onto a substrate or lead frame using specific processes, and the establishment of electrical connections and physical protection. Packaging not only provides mechanical support and environmental protection for the chip, such as moisture protection, dust protection, and chemical corrosion resistance, but also fulfills functions such as heat dissipation, signal transmission, and power distribution.

[0003] Among various packaging methods, especially in molding processes using thermocompression bonding or thermo-ultrasonic bonding, epoxy molding compounds are commonly used to seal and protect the chip and lead structure. This process typically involves placing the surface-mounted and wire-bonded chip unit into a mold, injecting molten EMC material, and then curing it. This process involves high temperature, high pressure, and rapid cooling, inevitably introducing thermal and mechanical stresses.

[0004] Although modern packaging materials and processes are highly mature, defects still frequently exist in actual production. During injection molding, the high-speed flowing molten EMC material impacts the bonded fine-diameter gold wires, causing the gold wires to bend, shift, or even short-circuit with adjacent lines. Excessive bending of the gold wires may also cause them to break from the external pin connection points, affecting the reliability of electrical connections. The main reason for this is that the gold wires themselves are relatively soft, especially at high temperatures, making them more prone to deformation. If the arc height is designed to be too high or the span is too large, the anti-disturbance capability will decrease, and poor mold flow channel design will cause turbulence. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a substrate structure for chip packaging, so as to solve the problems of bending, displacement or even short circuit with adjacent lines of gold wires during chip packaging.

[0006] To solve the above-mentioned technical problems, this utility model achieves the following solution: The present invention provides a substrate structure for chip packaging, comprising a lower substrate, a chip, and gold wires, wherein one end of the gold wires is connected to the chip. A chip slot is formed in the lower substrate, and a chip base is provided at the center of the chip slot, and the chip is placed on the chip base; The chip slot is provided with multiple wire slots, which are located between the side wall of the chip slot and the chip base; The wire groove is bent and folded along the bottom plane of the chip groove, and has at least one bend; The groove has an opening at both ends, the gold wire is installed in the groove, and the two ends of the gold wire extend out from the two openings respectively.

[0007] Preferably, the upper surface of the frame of the lower substrate is provided with a plurality of pin slots, the number of pin slots being the same as the number of wire slots, and their positions corresponding.

[0008] Preferably, an annular limiting groove is also formed on the upper surface of the frame of the lower substrate. The annular limiting groove passes through the middle of the plurality of pin slots, and the depth of the annular limiting groove is greater than the depth of the pin slots. The pin slot has a pin installed inside, and the pin has a snap-fit ​​structure for snapping into the annular limiting slot.

[0009] Preferably, a pad is provided at each end of the groove, and the upper surface of the pad is on the same horizontal plane as the upper surface of the chip; One side of the pad abuts against the wire groove, and the other side abuts against the side wall of the chip groove or the chip base; The height of the groove is greater than the sum of the heights of the chip and the chip base.

[0010] Preferably, a metal plate is mounted at the bottom of the pin slot, with both ends of the metal plate extending out of the pin slot and respectively attached to the outer wall of the lower substrate and the inner wall of the chip slot; The middle part of the metal plate is recessed towards the bottom of the annular limiting groove to form a U-shaped groove, and the U-shaped groove is in close contact with the side walls and bottom surface of the annular limiting groove.

[0011] Preferably, the snap-fit ​​structure is a U-shaped protrusion formed by a portion of the pin recessing into the bottom of the annular limiting groove.

[0012] Preferably, the bottom of the wire groove is fixed to the bottom of the chip groove; The outer wall of the groove is bent and folded to form a solute tank; The chip base has an equal number of slots arranged on opposite sides. Two adjacent slots are independent of each other, and the distance between each slot is equal.

[0013] Preferably, the substrate structure further includes an upper substrate, the lower surface of the frame of the upper substrate having an annular limiting block, the size of the annular limiting block being the same as the size of the annular limiting groove, and their positions corresponding to each other; When the upper substrate is installed on the lower substrate, the annular limiting block is installed in the annular limiting groove.

[0014] Preferably, two snap-fit ​​grooves are formed on the inner sidewall of the lower substrate, and the two snap-fit ​​grooves are located on opposite sides of each other. Two connecting rods are provided on the inner sidewall of the upper substrate, and the two connecting rods are located on opposite sides of each other. The connecting rods are elastic. The end of the connecting rod is provided with a snap-fit ​​block, which has an inclined surface and a horizontal surface. The horizontal surface is close to the inner side wall of the upper substrate and is positioned towards the outer side wall of the upper substrate. One side of the upper substrate has a solute channel that extends from the outer wall to the inner wall of the upper substrate, allowing molten epoxy resin to flow in. The positions of the snap-fit ​​block and the snap-fit ​​groove correspond to each other. When the upper substrate is covered and installed on the lower substrate, the snap-fit ​​block is snapped into the snap-fit ​​groove.

[0015] Compared with the prior art, the beneficial effects of this utility model are: 1. The chip is placed on a chip base at the center of the lower substrate, within a chip slot, achieving mechanical fixation and establishing a heat conduction path. One end of the gold wire is connected to the chip's pad via a bonding process. The other end needs to be connected to a conductive pin or upper-layer wiring. In traditional packaging, the gold wire spans the air in a suspended arc; in this design, the gold wire is embedded and housed within the slot. The gold wire is laid along the trajectory of the slot, entering from one opening, bending, and exiting from the other. Bending changes the direction of the gold wire to adapt to different wiring requirements while restricting its degrees of freedom. After the gold wire connection is completed, molding is performed. Because the gold wire is physically constrained and partially covered by the slot, it is less prone to displacement or deformation when impacted by mold fluid during injection molding. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a substrate structure for chip packaging according to the present invention.

[0017] Figure 2 This is a schematic diagram of the lower substrate in a substrate structure for chip packaging according to the present invention.

[0018] Figure 3 for Figure 2 Enlarged view of point a in the middle.

[0019] Figure 4 This is a partial structural diagram of a substrate structure for chip packaging according to the present invention.

[0020] Figure 5 This is a schematic diagram of the pin structure in a substrate structure for chip packaging according to the present invention.

[0021] Figure 6This is a partial structural diagram of the upper substrate in a substrate structure for chip packaging according to the present invention.

[0022] Figure 7 This is a schematic diagram of the connecting rod and snap-fit ​​block in a substrate structure for chip packaging according to this utility model.

[0023] The following labels are used in the attached diagram: 1. Lower substrate; 2. Chip; 3. Gold wire; 11. Chip groove; 12. Chip base; 13. Wire groove; 14. Pin groove; 15. Annular limiting groove; 16. Pin; 17. Pad; 18. Snap-fit ​​groove; 131. Bending; 132. Opening; 133. Solute tank; 141. Metal plate; 1411. U-shaped groove; 161. Snap-fit ​​structure; 401. Annular limiting block; 402. Connecting rod; 403. Snap-fit ​​block; 404. Solute channel; 4031. Inclined surface; 4032. Horizontal surface. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments, so that the advantages and features of the present utility model can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present utility model. Obviously, the embodiments described in this utility model are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0025] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0026] Example 1: The specific structure of this utility model is as follows: like Figures 1 to 3 As shown, a substrate structure for chip packaging includes a lower substrate 1, a chip 2, and gold wires 3, one end of which is connected to the chip 2. A chip groove 11 is formed in the lower substrate 1, and a chip base 12 is disposed at the center of the chip groove 11, on which the chip 2 is placed. A plurality of wire grooves 13 are provided in the chip groove 11, and the wire grooves 13 are located between the sidewall of the chip groove 11 and the chip base 12. The wire grooves 13 are bent and folded along the bottom plane of the chip groove 11 and have at least one bend 131. Each end of the wire groove 13 has an opening 132, and the gold wires 3 are installed in the wire grooves 13, with each end of the gold wires 3 extending out from the two openings 132 respectively.

[0027] In this embodiment, chip 2 is placed on chip base 12 at the center of lower substrate 1, located within chip groove 11, achieving mechanical fixation and establishing a heat conduction path. One end of gold wire 3 is connected to the pad of chip 2 via bonding process. The other end needs to be connected to conductive pins or upper layer wiring. In conventional packaging, gold wire 3 spans the air in a suspended arc shape; however, in this design, gold wire 3 is embedded and housed inside groove 13. Gold wire 3 is laid along the trajectory of groove 13, entering from one opening 132, and exiting from the other opening 132 after bending. Bending 131 can change the direction of gold wire to adapt to different wiring requirements, while restricting its degree of freedom. After the gold wire connection is completed, molding is performed. Since gold wire 3 is physically limited and partially covered by groove 13, it is not easy to displace or deform when impacted by mold fluid during injection molding.

[0028] Furthermore, a plurality of pin slots 14 are provided on the upper surface of the frame of the lower substrate 1. The number of pin slots 14 is the same as the number of wire slots 13, and their positions correspond.

[0029] In this embodiment, one opening 132 of the wire groove 13 leads to the corresponding pin slot 14. The gold wire 3 starts from the chip pad, runs along the wire groove 13, is bent to adjust its direction, and is led out from the opening 132 at the end of the wire groove to connect to the pin or conductive terminal located in the pin slot 14. This achieves an integrated layout of the complete electrical path from the chip to the external I / O terminal.

[0030] like Figure 5 As shown, further, an annular limiting groove 15 is also provided on the upper surface of the frame of the lower substrate 1. The annular limiting groove 15 penetrates the middle of the plurality of pin slots 14, and the depth of the annular limiting groove 15 is greater than the depth of the pin slots 14. A pin 16 is installed in the pin slot 14, and the pin 16 has a snap-fit ​​structure 161 for snapping into the annular limiting groove 15.

[0031] In this embodiment, dual fixation is achieved through the snap-fit ​​structure 161 and the annular limiting groove 15. The pin groove 14 provides radial or axial limiting, while the annular limiting groove 15 provides circumferential locking force to prevent the pin 16 from sliding laterally or tilting. In conventional packaging, the pin 16 is supported only by the sidewall of the pin groove 14, which is prone to slight displacement under high injection pressure or thermal expansion, leading to poor soldering or open circuits. Furthermore, this design avoids the situation where the pin 16 pulls on the gold wire 3 during subsequent bending, causing the contact point between the pin 16 and the gold wire 3 to break.

[0032] Furthermore, a pad 17 is provided at each end of the wire groove 13, and the upper surface of the pad 17 is on the same horizontal plane as the upper surface of the chip 2; one side of the pad 17 abuts against the wire groove 13, and the other side abuts against the side wall of the chip groove 11 or the chip base 12; the height of the wire groove 13 is greater than the sum of the heights of the chip 2 and the chip base 12.

[0033] In this embodiment, the upper surface of the pad 17 is at the same level as the upper surface of the chip 2, forming a continuous and flat bonding support platform. In traditional packaging, there is a height difference between the surface of the chip 2 and the surface of the lower substrate 1, requiring the gold wire 3 to "climb" to connect, resulting in abrupt changes in curvature near the bonding point, which easily leads to stress concentration and breakage under thermal cycling or vibration. This technical solution constructs an equal-height connection platform through the pad 17, ensuring that the starting and ending points of the gold wire 3 are at the same level as the chip 2, achieving a smooth transition and reducing bending stress.

[0034] like Figure 4 As shown, further, a metal plate 141 is installed at the bottom of the pin slot 14, and the two ends of the metal plate 141 extend out of the pin slot 14 and are respectively attached to the outer wall of the lower substrate 1 and the inner wall of the chip slot 11; the middle part of the metal plate 141 is recessed towards the bottom of the annular limiting groove 15 to form a U-shaped groove 1411, and the U-shaped groove 1411 is in close contact with the two side walls and the bottom surface of the annular limiting groove 15.

[0035] In this embodiment, the metal plate 141 serves as a rigid substrate, enhancing the structural strength of the pin slot 14 and supporting the pins 16. The U-shaped groove 1411 is embedded in the annular limiting groove 15, forming a continuous circumferential mechanical latch, significantly improving the overall shear and pull-out resistance of the pins 16. The two ends of the metal plate 141 are respectively attached to the inner wall of the chip slot 11 and the outer wall of the lower substrate 1, allowing specific pins to achieve low-impedance cross-regional connections through the metal plate 141, supporting the construction of common source or common ground planes, and improving signal integrity. The metal plate 141 has high thermal conductivity, allowing heat to be conducted from inside the chip slot 11 to the metal plate 141 and quickly dissipated through the pins 16, forming an auxiliary heat dissipation path and reducing local temperature rise.

[0036] Furthermore, the snap-fit ​​structure 161 is a U-shaped protrusion formed by a portion of the pin 16 recessed into the bottom of the annular limiting groove 15.

[0037] In this embodiment, when pin 16 is installed in place, the U-shaped protrusion is embedded in the deeper annular limiting groove 15, forming a mechanical interlock. Pin 16 is inserted into the pin slot 14 from above; during the insertion process, the U-shaped protrusion is squeezed by the side wall of the annular limiting groove 15, resulting in slight elastic deformation; when the U-shaped protrusion reaches the position of the annular limiting groove 15, it automatically springs back and locks into it; achieving self-locking fixation without the need for additional screws or adhesives. It should be noted that the locking structure 161 can also be an additional component, such as a block.

[0038] Furthermore, the bottom of the wire groove 13 is fixed to the bottom of the chip groove 11; the outer wall of the wire groove 13 is bent and folded to form a solute tank 133; an equal number of wire grooves 13 are arranged on opposite sides of the chip base 12, two adjacent wire grooves 13 are independent of each other, and the distance between each wire groove 13 is equal.

[0039] In this embodiment, the independent slots 13 can avoid signal crosstalk, are suitable for high-frequency or analog circuits, and the layout features of the slots 13 are highly scalable. The number of slots can be increased or decreased according to the number of chip pins to adapt to various package specifications.

[0040] like Figures 6-7 As shown, and refer to Figure 1 Furthermore, the substrate structure also includes an upper substrate 4, the lower surface of the frame of the upper substrate 4 having an annular limiting block 401, the size of the annular limiting block 401 being the same as the size of the annular limiting groove 15 and corresponding to each other in position; when the upper substrate 4 is covered and installed on the lower substrate 1, the annular limiting block 401 is installed in the annular limiting groove 15.

[0041] In this embodiment, the annular limiting block 401 serves as the top cover plate for sealing the chip slot 11 and its internal structure. It can be made of ceramic, metal, or polymer materials, possessing certain mechanical strength and environmental protection capabilities. Together with the lower substrate 1, it forms a complete packaging cavity. Traditional packaging covers are prone to misalignment, affecting sealing and appearance. The interference fit or transition fit between the annular limiting block 401 and the annular limiting groove 15 automatically corrects minor deviations during assembly. Furthermore, the packaging structure with the annular limiting block 401 and the annular limiting groove 15 supports various sealing methods such as thermosetting bonding, laser welding, and adhesive sealing. If the annular limiting block 401 is made of metal, it can also provide electromagnetic shielding.

[0042] Furthermore, two snap-fit ​​grooves 18 are formed on the inner sidewall of the lower substrate 1, and the two snap-fit ​​grooves 18 are located on opposite sides; two connecting rods 402 are provided on the inner sidewall of the upper substrate 4, and the two connecting rods 402 are located on opposite sides, and the connecting rods 402 are elastic; a snap-fit ​​block 403 is provided at the end of the connecting rod 402, the snap-fit ​​block 403 has an inclined surface 4031 and a horizontal surface 4032, the horizontal surface 4032 is close to the inner sidewall of the upper substrate 4, and the horizontal surface 4032 is set towards the outer sidewall of the upper substrate 4; a solute channel 404 is provided on one side of the upper substrate 4, the solute channel 404 extends from the outer wall of the upper substrate 4 to the inner wall, for the inflow of molten epoxy resin; the snap-fit ​​block 403 is positioned corresponding to the snap-fit ​​grooves 18, and when the upper substrate 4 is installed on the lower substrate 1, the snap-fit ​​block 403 is snapped into the snap-fit ​​groove 18.

[0043] In this embodiment, the chip 2 mounting, gold wire bonding, and pin 16 installation processes are completed on the lower substrate. The upper substrate 4 is aligned with the lower substrate 1, and the annular limiting block 401 is inserted into the annular limiting groove 15 to achieve initial positioning. With continued downward pressure, the connecting rod 402 bends under force, and the inclined surface of the locking block 403 slides to the locking groove 18 position. The connecting rod 402 elastically rebounds, and the horizontal surface 4032 locks into the groove to complete mechanical locking. Heated and molten epoxy resin is injected through the solute channel 404 to fill the gaps in the chip groove 11, wire groove 13, and pin 16 areas. After the resin cures, a complete sealing layer is formed, further enhancing structural strength and environmental protection capabilities.

[0044] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural or procedural transformations made based on the contents of the present utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present utility model.

Claims

1. A substrate structure for chip packaging, characterized in that, It includes a lower substrate (1), a chip (2) and a gold wire (3), one end of which is connected to the chip (2); A chip slot (11) is provided in the lower substrate (1), and a chip base (12) is provided at the center of the chip slot (11). The chip (2) is placed on the chip base (12). The chip slot (11) is provided with a plurality of wire slots (13), and the wire slots (13) are located between the side wall of the chip slot (11) and the chip base (12). The wire groove (13) is bent and folded along the bottom plane direction of the chip groove (11) and has at least one bend (131). The wire groove (13) has an opening (132) at both ends. The gold wire (3) is installed in the wire groove (13), and the two ends of the gold wire (3) extend out from the two openings (132) respectively.

2. The substrate structure for chip packaging as described in claim 1, characterized in that, The upper surface of the frame of the lower substrate (1) is provided with a plurality of pin slots (14), the number of pin slots (14) is the same as the number of wire slots (13), and their positions correspond.

3. The substrate structure for chip packaging as described in claim 2, characterized in that, The upper surface of the frame of the lower substrate (1) is also provided with an annular limiting groove (15), the annular limiting groove (15) penetrates the middle of the multiple pin slots (14), and the depth of the annular limiting groove (15) is greater than the depth of the pin slots (14). The pin slot (14) has a pin (16) installed in it. The pin (16) has a snap-fit ​​structure (161) for snapping into the annular limiting slot (15).

4. The substrate structure for chip packaging as described in claim 1, characterized in that, A pad (17) is provided at each end of the groove (13), and the upper surface of the pad (17) is on the same horizontal plane as the upper surface of the chip (2). One side of the pad (17) abuts against the wire groove (13), and the other side abuts against the side wall of the chip groove (11) or the chip base (12); The height of the groove (13) is greater than the sum of the heights of the chip (2) and the chip base (12).

5. The substrate structure for chip packaging as described in claim 3, characterized in that, A metal plate (141) is installed at the bottom of the pin slot (14), and the two ends of the metal plate (141) extend out of the pin slot (14) and are respectively attached to the outer wall of the lower substrate (1) and the inner wall of the chip slot (11). The middle part of the metal plate (141) is recessed towards the bottom of the annular limiting groove (15) to form a U-shaped groove (1411), and the U-shaped groove (1411) is in close contact with the side walls and bottom surface of the annular limiting groove (15).

6. The substrate structure for chip packaging as described in claim 3, characterized in that, The snap-fit ​​structure (161) is a U-shaped protrusion formed by a portion of the pin (16) recessed into the bottom of the annular limiting groove (15).

7. The substrate structure for chip packaging as described in claim 1, characterized in that, The bottom of the wire groove (13) is fixed to the bottom of the chip groove (11); The outer wall of the groove (13) is bent and folded to form a solute tank (133). The chip base (12) has an equal number of slots (13) arranged on opposite sides. Two adjacent slots (13) are independent of each other, and the distance between each slot (13) is equal.

8. The substrate structure for a chip package of claim 3, wherein, The substrate structure also includes an upper substrate (4), the lower surface of the frame of the upper substrate (4) has an annular limiting block (401), the size of the annular limiting block (401) is the same as the size of the annular limiting groove (15), and their positions correspond to each other; When the upper substrate (4) is installed on the lower substrate (1), the annular limiting block (401) is installed in the annular limiting groove (15).

9. The substrate structure for a chip package of claim 8, wherein, Two snap-fit ​​grooves (18) are provided on the inner sidewall of the lower substrate (1), and the two snap-fit ​​grooves (18) are located on opposite sides. Two connecting rods (402) are provided on the inner sidewall of the upper substrate (4), and the two connecting rods (402) are located on opposite sides of each other. The connecting rods (402) are elastic. The end of the connecting rod (402) is provided with a snap-fit ​​block (403), the snap-fit ​​block (403) has an inclined surface (4031) and a horizontal surface (4032), the horizontal surface (4032) is close to the inner sidewall of the upper substrate (4), and the horizontal surface (4032) is disposed towards the outer sidewall of the upper substrate (4). The upper substrate (4) has a solute channel (404) on one side, which extends from the outer wall to the inner wall of the upper substrate (4) for the inflow of molten epoxy resin. The positions of the snap-fit ​​block (403) and the snap-fit ​​groove (18) correspond to each other. When the upper substrate (4) is covered and installed on the lower substrate (1), the snap-fit ​​block (403) is snapped into the snap-fit ​​groove (18).

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