A multi-chip CLIP package structure

Abstract

The application provides a multi-chip CLIP packaging structure and relates to the technical field of chip packaging. The CLIP packaging structure comprises a substrate, the substrate is provided with a first direction arranged horizontally, a plurality of chips to be packaged are arranged on the substrate and spaced apart along the first direction, the upper surfaces of the plurality of chips are provided with a copper sheet, the copper sheet is provided with a plurality of bonding portions spaced apart along the first direction, the bonding portions are the same in profile as the chips, the lower surfaces of the bonding portions can be bonded to the chips through a welding layer, the upper surfaces of the bonding portions are provided with a reinforcing portion protruding upward, the reinforcing portion comprises a plurality of reinforcing members extending inward from the corners of the bonding portions, the reinforcing members can inhibit thermal stress generated in the reflow soldering process to a certain extent, the corners of the bonding portions are prevented from warping, the structural stability of the bonding portions is improved, the integrity of the interconnection between the copper sheet and the chips is ensured, the mechanical stress borne by the chips and the possibility of chip breakage are reduced, and the reliability of the power module is ensured.

Description

Technical Field

[0001] This invention relates to the field of chip packaging technology, and in particular to a multi-chip CLIP packaging structure. Background Technology

[0002] Packaging technology for power chips is used for efficient interconnection with external circuits, especially in high-power applications where the packaging structure directly affects the full utilization of chip performance. Traditional power modules commonly use wire bonding, such as aluminum bonding wires to achieve electrical connections on the chip's surface. However, this method faces challenges such as large parasitic parameters and limited heat dissipation under high-frequency and high-current conditions. To overcome these limitations, bonding methods have evolved from early gold wires to aluminum wires or aluminum strips, then to copper wire bonding, and further to Cu Clip bonding. Cu Clip bonding achieves lower package resistance, higher current capacity, and better thermal conductivity, meeting the increasing demands for power density and efficiency. Cu Clip uses a solid copper bridge to achieve direct connection between the chip and pins, partially replacing traditional wire bonding, significantly improving electrical and thermal management performance, and reducing process costs, such as reducing the need for silver plating. Cu Clip bonding has evolved into various forms such as all-copper bonding and copper-plus-wire bonding, and is widely used in servers, portable devices, and power management systems.

[0003] In power modules using Cu Clip packaging, the Cu Clip, semiconductor chip, substrate (such as ceramic copper-clad substrate or lead frame), and solder layer (such as solder paste) are made of different materials. These materials have different coefficients of thermal expansion. During the reflow soldering process in packaging manufacturing (which involves heating and cooling), thermal stress is easily generated, which can cause warping at the corners of the Cu Clip. This may affect the integrity of the interconnection between the Cu Clip and the chip, and may also cause the chip to be subjected to uneven mechanical stress, or even cause the chip to break, thereby affecting the reliability of the power module.

[0004] The information disclosed in the background section of this invention is intended only to enhance the understanding of the general background of this invention, and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] Therefore, it is necessary to provide a multi-chip CLIP packaging structure to address the problems existing in the current CLIP packaging structure.

[0006] The above objectives are achieved through the following technical solutions:

[0007] A multi-chip CLIP package structure includes a substrate with a horizontally arranged first direction. Multiple chips to be packaged are mounted on the substrate at intervals along the first direction. The upper surfaces of the multiple chips are provided with a copper sheet. The copper sheet has multiple adhesive portions spaced along the first direction, each adhesive portion having the same outline as a chip. The lower surface of each adhesive portion can be bonded to a chip through a solder layer. The upper surface of the adhesive portion is provided with an upwardly protruding reinforcing portion, which includes multiple reinforcing members extending inward from the corners of the adhesive portion.

[0008] Furthermore, a connecting part is provided between two adjacent adhesive parts. The side of the adhesive part closer to the connecting part is the first side, and the side farther away from the connecting part is the second side. The second side is provided with a suppressing member. When the two corners of the second side warp to different degrees due to stress differences, the suppressing member applies a downward force to the corner with a higher degree of warping.

[0009] Furthermore, the suppressing component is made of a rigid material, and its two ends are respectively connected to the two corners of the second side.

[0010] Furthermore, a support member is formed in the middle of the suppressing member, the support member abuts against the substrate, and a limiting member is provided on the inner side of the support member. The limiting member is elastic and abuts against the side surface of the chip to apply an inward force along the first direction to the side surface of the chip. The surface of the limiting member abutting against the chip has an anti-slip structure.

[0011] Furthermore, multiple side grooves are formed on the lower surface of the adhesive portion, extending from the outside of the adhesive portion to its interior.

[0012] Furthermore, the lower surface of the adhesive part has multiple annular grooves that communicate with the side grooves. The diameters of the multiple annular grooves increase sequentially, and their centers coincide with the center of the adhesive part. The width of the annular grooves is smaller than the width of the side grooves.

[0013] Furthermore, the side grooves correspond one-to-one with the reinforcing members, and the side grooves are arranged along the length direction of the reinforcing members, with the side grooves forming together on the adhesive part and the reinforcing members.

[0014] Furthermore, the width of the side groove gradually increases from bottom to top.

[0015] Furthermore, the reinforcing member extends from the corner of the adhesive part towards its center, and the included angle formed by two adjacent reinforcing members is equal to the included angle formed by the other two reinforcing members.

[0016] Furthermore, the height of the upward protrusion of the reinforcing member is less than the thickness of the adhesive portion.

[0017] The present invention has at least the following beneficial effects:

[0018] (1) The reinforcing member extends inward from the corner of the bonding part, which to a certain extent suppresses the thermal stress generated in the reflow soldering process, prevents the corner of the bonding part from warping, improves the structural stability of the bonding part, ensures the integrity of the interconnection between the copper sheet and the chip, thereby reducing the mechanical stress on the chip and the possibility of chip breakage, and ensuring the reliability of the power module.

[0019] (2) When the two corners on the second side warp to different degrees due to stress difference, the suppressor applies a downward force to the corner with higher warping degree so that the warping degree of the corner is reduced to be consistent with the warping degree of the other corner, so that the warping degree of the two corners on the second side is consistent, avoiding uneven warping phenomenon, thereby further reducing the possibility of chip breakage.

[0020] (3) The limiting member is elastic and abuts against the side surface of the chip to apply an inward force along the first direction to the side surface of the chip. The limiting members on the two suppressing members work together in the first direction to limit the copper sheet relative to the chip in the first direction. At the same time, the surface of the limiting member abutting against the chip is rough, and static friction is generated between the limiting member and the chip to limit the copper sheet relative to the chip in the second direction. The second direction is horizontal and perpendicular to the first direction, thereby preventing the copper sheet from drifting relative to the chip.

[0021] (4) The side slots remove air bubbles generated during the reflow soldering process, reducing voids in the solder paste and ensuring the bonding quality between the bonding part and the chip. In addition, during reflow soldering, the solder creep effect causes the solder paste at the edge to flow back into the side slots and fill the side slots, preventing the solder paste from overflowing to the outside of the bonding part and contaminating the lead frame. At the same time, the solder paste in the side slots can also increase the soldering area between the bonding part and the chip, further ensuring the bonding quality between the bonding part and the chip. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a multi-chip CLIP package structure provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 Top view;

[0024] Figure 3 for Figure 2 Sectional view along axis AA;

[0025] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0026] Figure 5 for Figure 1 Exploded view of the parts;

[0027] Figure 6 for Figure 1 Schematic diagram of the structure of the copper sheet;

[0028] Figure 7 A schematic diagram of a multi-chip CLIP package structure provided in another embodiment of the present invention;

[0029] Figure 8 for Figure 7 A schematic diagram of the structure of the copper sheet.

[0030] in:

[0031] 101. Substrate; 102. Chip; 103. Copper sheet; 104. Adhesive part; 105. Lead; 106. Extension part; 107. Connecting part;

[0032] 201. Reinforcing component; 202. Suppressing component; 203. Support component; 204. Limiting component; 205. Side groove; 206. Annular groove. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0034] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0035] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0036] like Figures 1 to 8 As shown, this embodiment of the invention provides a multi-chip CLIP packaging structure, including a substrate 101. The substrate 101 has a horizontally arranged first direction. A plurality of chips 102 to be packaged are mounted on the substrate 101 at intervals along the first direction. The upper surfaces of the plurality of chips 102 are provided with a copper sheet 103. The copper sheet 103 has a plurality of adhesive portions 104 arranged at intervals along the first direction. Each adhesive portion 104 has the same outline as a chip 102. The lower surface of each adhesive portion 104 can be bonded to a chip 102 through a solder layer. The upper surface of the adhesive portion 104 is provided with an upwardly protruding reinforcing portion. The reinforcing portion includes a plurality of reinforcing members 201 extending inward from the corners of the adhesive portion 104.

[0037] The reinforcing member 201 extends inward from the corner of the adhesive portion 104, which to a certain extent suppresses the thermal stress generated during the reflow soldering process, prevents the corner of the adhesive portion 104 from warping, improves the structural stability of the adhesive portion 104, and ensures the integrity of the interconnection between the copper sheet 103 and the chip 102. This reduces the mechanical stress on the chip 102 and the possibility of chip 102 breakage, thus ensuring the reliability of the power module. The reinforcing member 201 protruding from the upper surface of the adhesive portion 104 can also increase the heat dissipation area of ​​the copper sheet 103 and improve its heat dissipation capacity.

[0038] Understandably, the lower surface of the adhesive portion 104 is a solder layer. After heating and cooling before and after soldering, based on the differences in the thermal expansion coefficients of the materials and the principle of thermal expansion and contraction, the edges of the adhesive portion 104 generally warp upwards. This warping can damage the integrity of the interconnection between the adhesive portion 104 and the chip 102, and may also cause the chip 102 to experience uneven mechanical stress, even leading to chip 102 breakage, thus affecting the reliability of the power module. The reinforcing member 201 acts as a reinforcing rib, which can, to a certain extent, suppress the thermal stress generated during the reflow soldering process and prevent the edges of the adhesive portion 104 from warping upwards. The solder layer is solder paste, a paste-like substance made by mixing flux and solder alloy powder. It melts into a liquid state when heated to a certain temperature and solidifies after cooling to achieve the soldering of the adhesive portion 104 and the chip 102. The upper and lower surfaces and corners of the adhesive portion 104 are rounded to ensure a smooth transition between the adhesive portion 104 and the chip 102, avoiding damage or scratches to the chip 102 from straight corners. In addition, the chip 102 is mostly rectangular with four corners, so the adhesive portion 104 also has four corners and four reinforcing members 201. The following description uses a rectangular chip 102 as an example.

[0039] The substrate 101 has pins 105, and the copper sheet 103 also has an extension 106. The extension 106 is connected to one of the adhesive parts 104. The extension 106 is bonded to the pins 105 through a solder layer. The bonding process principle and specific process are the same as the bonding process between the adhesive part 104 and the chip 102.

[0040] In one embodiment, a connecting portion 107 is provided between two adjacent adhesive portions 104. The side of the adhesive portion 104 closer to the connecting portion 107 is the first side, and the side away from the connecting portion 107 is the second side. An inhibiting member 202 is provided on the second side. When the two corners of the second side warp to different degrees due to stress differences, the inhibiting member 202 applies a downward force to the corner with a higher degree of warping.

[0041] When the two corners on the second side warp to different degrees due to stress differences, the suppressor 202 applies a downward force to the corner with a higher degree of warping, so that the degree of warping of the corner is reduced to be consistent with the degree of warping of the other corner, so that the degree of warping of the two corners on the second side is consistent, avoiding uneven warping, thereby further reducing the possibility of chip 102 breaking.

[0042] It is worth noting that the different degrees of warping at the two corners on the second side due to stress differences only indicate that the degree of warping is different. This includes the following situations: one corner is not warped, while the other corner is warped; or one corner warps less, while the other corner warps more. Furthermore, since the area of ​​the adhesive portion 104 is smaller than the corresponding area of ​​the chip 102, providing the suppressor 202 only on the second side is sufficient to prevent uneven warping at the two corners on the second side.

[0043] In one embodiment, the suppressor 202 is made of a rigid material, and its two ends are respectively connected to two corners of the second side.

[0044] The suppressing member 202 can be a rod, with its two ends connected to the two corners of the second side, respectively. When the two corners of the second side warp to different degrees due to stress differences, the suppressing member 202 will not bend. The corner with a lower degree of warping acts on one end of the suppressing member 202, causing that end of the suppressing member 202 to exert a downward force on the other end, thereby exerting a downward force on the corner with a higher degree of warping, thus making the warping of the two corners of the second side consistent.

[0045] In one embodiment, a support member 203 is formed in the middle of the suppressor 202. The support member 203 abuts against the substrate 101. A limiting member 204 is provided on the inner side of the support member 203. The limiting member 204 is elastic and abuts against the side surface of the chip 102 to apply an inward force along a first direction to the side surface of the chip 102. The surface of the limiting member 204 that abuts against the chip 102 has an anti-slip structure.

[0046] Since the lower surface of the adhesive portion 104 is bonded to the upper surface of the chip 102 through a solder layer, during reflow soldering, the solder paste melts, and the copper sheet 103 is prone to drifting relative to the chip 102, affecting the bonding quality between the adhesive portion 104 and the chip 102. The limiting member 204 is elastic and abuts against the side surface of the chip 102 to apply an inward force along the first direction to the side surface of the chip 102. The limiting members 204 on the two suppressing members 202 work together in the first direction to limit the copper sheet 103 relative to the chip 102 in the first direction. At the same time, the surface of the limiting member 204 abutting against the chip 102 is rough, and static friction is generated between the limiting member 204 and the chip 102 to limit the copper sheet 103 relative to the chip 102 in the second direction. When the chip 102 is rectangular, the second direction is horizontal and perpendicular to the first direction, thereby preventing the copper sheet 103 from drifting relative to the chip 102.

[0047] The surface of the limiting member 204 that abuts against the chip 102 has an anti-slip structure. This anti-slip structure can be anti-slip textures formed on the limiting member 204, an anti-slip layer provided on the limiting member 204, or the entire surface of the limiting member 204 has a certain roughness. The specific anti-slip structure can be selected and set according to requirements, and this application does not limit it. In actual operation, the copper sheet 103 is pressed downward relative to the chip 102, causing the limiting member 204 and the side surface of the chip 102 to move up and down relative to each other. At the same time, the limiting member 204 is compressed until the lower end of the supporting member 203 abuts against the substrate 101, and the limiting member 204 contacts the side surface of the chip 102. The limiting member 204 applies an inward force along the first direction to the side surface of the chip 102. Preferably, see Figure 4 and Figure 5 The limiting member 204 is a spring sheet with a first end and a second end. The limiting member 204 is bent to form a deformation ring, so that the first end and the second end are located on the same side of the deformation ring. When the deformation ring deforms in the first direction, the first end and the second end move relative to each other.

[0048] In this embodiment, multiple chips 102 are installed along the first direction, and adhesive portions 104 are also arranged sequentially along the first direction. Therefore, it is necessary to provide suppression members 202 and limiting members 204 on both sides of the copper sheet 103 in the first direction, so as to limit the copper sheet 103 relative to the chip 102 in the first and second directions, so as to avoid the copper sheet 103 drifting relative to the chip 102.

[0049] In other embodiments, this application may also package a single chip 102, see [link to relevant documentation]. Figure 7 and Figure 8 At this time, the copper sheet 103 has an adhesive portion 104, and the adhesive portion 104 and the extension portion 106 form a connecting portion 107. The side of the adhesive portion 104 closer to the connecting portion 107 is the first side, the side farther from the connecting portion 107 is the second side, and the other two sides are the third side and the fourth side, respectively. Suppressing members 202 and limiting members 204 can be provided on both the third and fourth sides. Since the two corners of the first side will not warp, the suppressing members 202 on the third and fourth sides can suppress the warping of the two corners of the second side, and simultaneously limit the copper sheet 103 relative to the chip 102 in two mutually perpendicular horizontal directions, preventing the copper sheet 103 from drifting relative to the chip 102. Preferably, suppressing members 202 and limiting members 204 are provided on the other three sides besides the first side to improve the ability to suppress warping of the two corners of the second side of the adhesive portion 104, and simultaneously improve the stability of the limiting position of the copper sheet 103 relative to the chip 102.

[0050] In one embodiment, a plurality of side grooves 205 are formed on the lower surface of the adhesive portion 104, and the side grooves 205 extend from the outside of the adhesive portion 104 toward its interior.

[0051] The side groove 205 removes air bubbles generated during the reflow soldering process, reduces voids in the solder paste, and ensures the bonding quality between the bonding portion 104 and the chip 102. Furthermore, during reflow soldering, the solder creep effect causes solder paste at the edges to flow back into the side groove 205 and fill it completely, preventing solder paste from overflowing to the outside of the bonding portion 104 and contaminating the substrate 101. Simultaneously, the solder paste within the side groove 205 increases the bonding area between the bonding portion 104 and the chip 102, further ensuring the bonding quality between them.

[0052] In one embodiment, see Figure 6 The lower surface of the adhesive portion 104 has a plurality of annular grooves 206 that communicate with the side grooves 205. The diameters of the plurality of annular grooves 206 increase sequentially and their centers coincide with the center of the adhesive portion 104. The width of the annular grooves 206 is smaller than the width of the side grooves 205.

[0053] Air bubbles enter the side groove 205 from the annular groove 206 and are discharged, improving the efficiency of air bubble discharge, further reducing voids in the solder paste, and ensuring the bonding quality between the bonding part 104 and the chip 102.

[0054] The width of the annular groove 206 is greater than or equal to the diameter of the bubble molecules in the solder paste, but less than the diameter of the melted solder paste droplets, so that the annular groove 206 only allows bubbles to enter, but does not allow the melted solder paste droplets to enter; the width of the side groove 205 is greater than or equal to the diameter of the melted solder paste droplets, allowing the melted solder paste droplets to enter.

[0055] In one embodiment, the side grooves 205 correspond one-to-one with the reinforcing members 201, and the side grooves 205 are arranged along the length direction of the reinforcing members 201. The side grooves 205 are formed together on the adhesive portion 104 and the reinforcing members 201.

[0056] The number of side grooves 205 and reinforcing members 201 are equal. After the solder paste flows back into the side grooves 205 and solidifies, the strength of the reinforcing members 201 is increased, thereby further suppressing the thermal stress generated in the reflow soldering process, preventing the corners of the adhesive part 104 from warping, and improving the structural stability of the adhesive part 104.

[0057] The side groove 205 is formed together with the adhesive portion 104 and the reinforcing member 201. In other words, the upper and lower thicknesses of the side groove 205 are greater than the thickness of the adhesive portion 104 but less than the sum of the thicknesses of the adhesive portion 104 and the reinforcing member 201. This allows the solder paste to flow back into the side groove 205 and solidify, and solder paste is also present in the reinforcing member 201, thereby increasing the strength of the reinforcing member 201.

[0058] In one embodiment, the width of the side groove 205 gradually increases from bottom to top, that is, the cross-section of the side groove 205 is an inverted dovetail shape. After the solder paste flows back into the side groove 205 and solidifies, it can prevent the solidified solder paste from separating from the side groove 205, thereby further ensuring the bonding quality between the bonding part 104 and the chip 102.

[0059] Preferably, the average width of the side groove 205 is equal to the thickness of the adhesive portion 104.

[0060] In other embodiments not shown, the cross-section of the side groove 205 may also be T-shaped or other shapes, which can also prevent the solidified solder paste from separating from the side groove 205.

[0061] In one embodiment, the reinforcing member 201 extends from the corner of the adhesive portion 104 toward its center, and the included angle formed by two adjacent reinforcing members 201 is equal to the included angle formed by the other two reinforcing members 201, so as to further improve the structural stability of the adhesive portion 104.

[0062] In one embodiment, the height of the upward protrusion of the reinforcing member 201 is less than the thickness of the adhesive portion 104.

[0063] The working principle of this invention is as follows:

[0064] Multiple chips 102 are mounted on a substrate 101. A copper sheet 103 is pressed downward relative to the chips 102, causing the limiting member 204 to move vertically relative to the side surface of the chips 102. Simultaneously, the limiting member 204 is compressed until the lower end of the support member 203 abuts against the substrate 101. At the same time, the limiting member 204 contacts the side surface of the chips 102, and the limiting member 204 applies an inward force along a first direction to the side surface of the chips 102. The limiting members 204 on the two suppressing members 202 work together in the first direction to limit the copper sheet 103 relative to the chips 102 in the first direction. At the same time, the surface of the limiting member 204 abutting against the chips 102 is rough, and static friction is generated between the limiting member 204 and the chips 102 to limit the copper sheet 103 relative to the chips 102 in a second direction. This prevents the copper sheet 103 from drifting relative to the chips 102 during reflow soldering with solder paste, ensuring the bonding quality between the adhesive part 104 and the chips 102.

[0065] The reinforcing member 201 extends inward from the corner of the adhesive portion 104, suppressing the thermal stress generated during the reflow soldering process to a certain extent, preventing warping of the corner of the adhesive portion 104, improving the structural stability of the adhesive portion 104, ensuring the integrity of the interconnection between the copper sheet 103 and the chip 102, thereby reducing the mechanical stress on the chip 102 and the possibility of chip 102 breakage, and ensuring the reliability of the power module. Furthermore, when the two corners on the second side warp to different degrees due to stress differences, the suppressing member 202 will not bend. The corner with lower warping acts on one end of the suppressing member 202, causing one end of the suppressing member 202 to exert a downward force on the other end. The suppressing member 202 applies a downward force to the corner with higher warping, reducing the warping degree of that corner to be consistent with the warping degree of the other corner, making the warping degrees of the two corners on the second side consistent, avoiding uneven warping, and further reducing the possibility of chip 102 breakage.

[0066] The air bubbles generated during the reflow soldering process are discharged through the annular groove 206 and the side groove 205, reducing voids in the solder paste and ensuring the bonding quality between the bonding part 104 and the chip 102. In addition, during reflow soldering with solder paste, the solder creep effect causes the solder paste at the edge to flow back into the side groove 205 and fill the side groove 205, preventing the solder paste from overflowing to the outside of the bonding portion 104 and contaminating the substrate 101. At the same time, the solder paste in the side groove 205 can also increase the soldering area between the bonding portion 104 and the chip 102, further ensuring the bonding quality between the bonding portion 104 and the chip 102. Since the side groove 205 is formed together with the bonding portion 104 and the reinforcing member 201, and the cross-section of the side groove 205 is an inverted dovetail shape, after the solder paste flows back into the side groove 205 and solidifies, it can improve the strength of the reinforcing member 201, further suppress the thermal stress generated in the reflow soldering process, and prevent the solidified solder paste from detaching from the side groove 205, ensuring the bonding quality between the bonding portion 104 and the chip 102.

[0067] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A multi-chip CLIP package structure, characterized in that, The substrate includes a horizontally arranged first direction. Multiple chips to be packaged are mounted on the substrate at intervals along the first direction. The upper surfaces of the multiple chips are provided with a copper sheet. The copper sheet has multiple adhesive portions at intervals along the first direction. Each adhesive portion has the same outline as a chip. The lower surface of each adhesive portion can be bonded to a chip through a solder layer. The upper surface of the adhesive portion is provided with an upwardly protruding reinforcing portion. The reinforcing portion includes multiple reinforcing members extending inward from the corners of the adhesive portion.

2. The multi-chip CLIP packaging structure according to claim 1, characterized in that, A connecting part is provided between two adjacent adhesive parts. The side of the adhesive part closer to the connecting part is the first side, and the side farther away from the connecting part is the second side. The second side is provided with a suppressing member. When the two corners of the second side warp to different degrees due to stress differences, the suppressing member applies a downward force to the corner with a higher degree of warping.

3. The multi-chip CLIP packaging structure according to claim 2, characterized in that, The suppressor is made of a rigid material, and its two ends are connected to the two corners of the second side, respectively.

4. The multi-chip CLIP packaging structure according to claim 3, characterized in that, A support member is formed in the middle of the suppressing member. The support member abuts against the substrate. A limiting member is provided on the inner side of the support member. The limiting member is elastic and abuts against the side surface of the chip to apply an inward force along a first direction to the side surface of the chip. The surface of the limiting member that abuts against the chip has an anti-slip structure.

5. The multi-chip CLIP packaging structure according to claim 1, characterized in that, Multiple side grooves are formed on the lower surface of the adhesive part, extending from the outside of the adhesive part to its interior.

6. The multi-chip CLIP packaging structure according to claim 5, characterized in that, The lower surface of the adhesive part has multiple annular grooves that communicate with the side grooves. The diameter of the multiple annular grooves increases sequentially and their centers coincide with the center of the adhesive part. The width of the annular grooves is smaller than the width of the side grooves.

7. The multi-chip CLIP packaging structure according to claim 6, characterized in that, The side grooves correspond one-to-one with the reinforcing members, and the side grooves are set along the length direction of the reinforcing members. The side grooves are formed together on the adhesive part and the reinforcing members.

8. The multi-chip CLIP packaging structure according to claim 7, characterized in that, The width of the side groove gradually increases from bottom to top.

9. The multi-chip CLIP packaging structure according to claim 1, characterized in that, The reinforcing member extends from the corner of the adhesive part towards its center, and the included angle formed by two adjacent reinforcing members is equal to the included angle formed by the other two reinforcing members.

10. The multi-chip CLIP packaging structure according to claim 1, characterized in that, The height of the upward protrusion of the reinforcing member is less than the thickness of the adhesive part.

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