Package structure

Abstract

The utility model relates to a packaging structure. The package structure includes: a lead frame; the functional chip is located on the lead frame, and the functional chip is electrically connected with the lead frame; and the electromagnetic shielding cover is located on the lead frame and covers the functional chip, and the electromagnetic shielding cover is electrically connected with the lead frame. According to the utility model, the functional chip is prevented from being influenced by external electromagnetic radiation, the limitation that the conductive terminal of the functional chip can only be led out from the bottom surface of the lead frame is broken, and the heat dissipation effect of the packaging structure is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of integrated circuit manufacturing, in particular to a packaging structure. Background Art

[0002] In a packaging structure including functional chips such as GaN chips, the functional chips mounted on the packaging substrate are directly encapsulated in a plastic encapsulation material through a plastic encapsulation process. Therefore, the heat generated during the operation of the functional chip can only be conducted to the packaging substrate, resulting in the focusing of heat in the packaging substrate and poor heat dissipation. At the same time, when functional chips such as GaN chips work in an electromagnetic radiation environment, they will be affected by electromagnetic radiation, which will cause the performance parameters of the functional chips to shift, shorten the early failure time, and affect the reliability of the packaging structure. In addition, the conductive terminals of the functional chips in the current packaging structure can only be led out through the packaging substrate, and the lead-out method is relatively single, which limits the further development of the performance of the packaging structure.

[0003] Therefore, how to reduce the impact of electromagnetic radiation on the functional chips in the packaging structure, improve the heat dissipation effect of the packaging structure, improve the performance of the packaging structure, and expand the functions of the packaging structure are technical problems that need to be solved urgently. Summary of the invention

[0004] The utility model provides a packaging structure, which is used for reducing the influence of electromagnetic radiation on a functional chip in the packaging structure, improving the heat dissipation effect of the packaging structure, improving the performance of the packaging structure, and expanding the function of the packaging structure.

[0005] According to some embodiments, the utility model provides a packaging structure, including:

[0006] Lead frame;

[0007] A functional chip is located on the lead frame, and the functional chip is electrically connected to the lead frame;

[0008] The electromagnetic shielding cover is located on the lead frame and covers the functional chip, and the electromagnetic shielding cover is electrically connected to the lead frame.

[0009] In some embodiments, the electromagnetic shield is a metal electromagnetic shield.

[0010] In some embodiments, it also includes:

[0011] The heat-conducting adhesive layer is located on the surface of the functional chip away from the lead frame, one side of the heat-conducting adhesive layer is bonded to the functional chip, and the other side of the heat-conducting adhesive layer is bonded to the electromagnetic shielding cover.

[0012] In some embodiments, the functional chip has a plurality of conductive terminals on a surface facing the lead frame, the lead frame includes a ground pin, and a portion of the conductive terminals are located on the ground pin and electrically connected to the ground pin;

[0013] The electromagnetic shielding cover is located on the grounding pin, and a conductive connection layer is provided between the electromagnetic shielding cover and the grounding pin.

[0014] In some embodiments, the electromagnetic shielding cover includes a first platform portion located on the functional chip and a second platform portion located on the ground pin, the conductive connection layer electrically connects the second platform portion and the ground pin, and the size of the second platform portion is smaller than the size of a portion of the conductive terminals.

[0015] In some embodiments, the functional chip is a GaN chip, and the conductive terminal electrically connected to the ground pin is a source conductive terminal.

[0016] In some embodiments, the lead frame further includes input / output pins, and another portion of the conductive terminals are located on the input / output pins and electrically connected to the input / output pins;

[0017] The electromagnetic shielding cover is located on the input / output pin, and an insulating isolation layer is provided between the electromagnetic shielding cover and the input / output pin.

[0018] In some embodiments, the electromagnetic shielding cover further includes a third platform portion, the third platform portion and the second platform portion are distributed on two opposite sides of the first platform portion, and the third platform portion is located on the insulating isolation layer.

[0019] In some embodiments, the conductive connection layer is a conductive adhesive layer, and the insulating isolation layer is an insulating adhesive layer.

[0020] In some embodiments, it also includes:

[0021] The plastic sealing layer at least covers the side walls of the electromagnetic shielding cover, and the top surface of the plastic sealing layer is flush with the top surface of the electromagnetic shielding cover.

[0022] The packaging structure provided by the utility model is provided with a lead frame, a functional chip located on the lead frame, and an electromagnetic shielding cover covering the functional chip. The electromagnetic shielding cover shields electromagnetic radiation in the external environment, and prevents the functional chip from being affected by the external electromagnetic radiation, thereby ensuring the stability of the performance parameters of the functional chip, achieving improvement in the performance of the packaging structure, and enabling the packaging structure to be applied in an electromagnetic radiation environment, thereby improving the reliability of the packaging structure and expanding the application field of the packaging structure. At the same time, by electrically connecting the electromagnetic shielding cover and the lead frame, and electrically connecting the functional chip and the lead frame, the signal of the functional chip can be led out through the lead frame and the electromagnetic shielding cover, breaking the limitation that the conductive terminal of the functional chip can only be led out from the bottom surface of the lead frame, thereby improving the design flexibility of the packaging structure and helping to expand the function of the packaging structure. Moreover, the electromagnetic shielding cover can also serve as a heat dissipation layer, so that the heat of the packaging structure can not only be dissipated from the lead frame to the lower part of the packaging structure, but also be dissipated from the upper part of the packaging structure through the electromagnetic shielding cover, avoiding heat accumulation inside the packaging structure, thereby improving the heat dissipation effect of the packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Attached Figure 1 It is a schematic diagram of a packaging structure in a specific implementation mode of the utility model;

[0024] Attached Figure 2 It is a schematic diagram of another packaging structure in a specific implementation manner of the utility model. DETAILED DESCRIPTION

[0025] The specific implementation of the packaging structure provided by the utility model is described in detail below with reference to the accompanying drawings.

[0026] This specific implementation provides a packaging structure, Figure 1 Schematic diagram of a packaging structure in a specific implementation mode of the utility model. Figure 1 As shown, the packaging structure includes:

[0027] Lead frame 12;

[0028] A functional chip 10 is located on the lead frame 12, and the functional chip 10 is electrically connected to the lead frame 12;

[0029] The electromagnetic shielding cover 16 is located on the lead frame and covers the functional chip 10 . The electromagnetic shielding cover 16 is electrically connected to the lead frame 12 .

[0030] Specifically, the lead frame 12 includes a plurality of pins. The lead frame 12 includes a top surface and a bottom surface that are relatively distributed. In one example, the functional chip 10 is connected to the top surface of the lead frame 12 along a first direction D1, and the first direction D1 is perpendicular to the top surface of the lead frame 12. The functional chip 10 is provided with a plurality of conductive terminals on one side of the lead frame 12, and the conductive terminals are used to electrically connect the functional chip 10 to the lead frame 12. The plurality described in this specific embodiment refers to more than two. The electromagnetic shielding cover 16 is provided on the lead frame 12 and covers (for example, wraps or semi-wraps) the functional chip 10. The electromagnetic shielding cover 16 is used to shield external electromagnetic radiation, thereby protecting the functional chip 10 from interference from external electromagnetic radiation.

[0031] This specific embodiment provides the electromagnetic shielding cover 16 on the lead frame, and the electromagnetic shielding cover 16 is provided on the functional chip 10, thereby shielding the electromagnetic radiation in the external environment, preventing the functional chip 10 from being affected by the external electromagnetic radiation, ensuring the stability of the performance parameters of the functional chip 10, achieving the improvement of the performance of the packaging structure, and also enabling the packaging structure to be applied in an electromagnetic radiation environment, thereby expanding the application field of the packaging structure. At the same time, the electromagnetic shielding cover 16 in this specific embodiment is electrically connected to the lead frame 12, so that the conductive terminals in the functional chip 10 can be led out from the electromagnetic shielding cover 16 through the lead frame 12, breaking the limitation that the conductive terminals of the functional chip can only be led out from the bottom surface of the lead frame, thereby improving the design flexibility of the packaging structure and helping to expand the function of the packaging structure. The electromagnetic shielding cover 16 is disposed on the functional chip 10, so that the heat of the packaging structure can not only be dissipated from the lead frame to the lower part of the packaging structure, but also can be dissipated from the upper part of the packaging structure through the electromagnetic shielding cover 16, thereby avoiding the accumulation of heat inside the packaging structure, thereby improving the heat dissipation effect of the packaging structure. In one example, the packaging structure also includes a welding lead, one end of the welding lead is electrically connected to the electromagnetic shielding cover 16, and the other end is electrically connected to the second functional device, so that the signal in the functional chip 10 is led out through the electromagnetic shielding cover 16 and the welding lead.

[0032] In order to further improve the heat dissipation effect of the packaging structure and the electromagnetic shielding effect of the packaging structure, in some embodiments, the electromagnetic shielding cover 16 is a metal electromagnetic shielding cover.

[0033] In some embodiments, the packaging structure further includes:

[0034] The thermally conductive adhesive layer 15 is located on the surface of the functional chip 10 facing away from the lead frame 12 . One side of the thermally conductive adhesive layer 15 is bonded to the functional chip 10 , and the other side of the thermally conductive adhesive layer 15 is bonded to the electromagnetic shielding cover 16 .

[0035] Specifically, the thermally conductive adhesive layer 15 is bonded to the surface of the functional chip 10 away from the lead frame 12 along the first direction D1, and one end of the thermally conductive adhesive layer 15 is bonded to the functional chip 10, and the other side is bonded to the electromagnetic shielding cover 16. By providing the thermally conductive adhesive layer 15 between the functional chip 10 and the electromagnetic shielding cover 16, on the one hand, the thermal conductivity between the functional chip 10 and the electromagnetic shielding cover 16 can be further enhanced, thereby further improving the heat dissipation effect of the packaging structure; on the other hand, the connection strength between the electromagnetic shielding cover 16 and the functional chip 10 can be enhanced to avoid the relative position between the electromagnetic shielding cover 16 and the functional chip 10 from being offset, thereby further ensuring the stability of the performance of the packaging structure.

[0036] In some embodiments, the functional chip 10 has a plurality of conductive terminals 111 on a surface facing the lead frame, the lead frame 12 includes a ground pin 121, and a portion of the conductive terminals 111 are located on the ground pin 121 and electrically connected to the ground pin 121;

[0037] The electromagnetic shielding cover 16 is located on the ground pin 121 , and a conductive connection layer 13 is provided between the electromagnetic shielding cover 16 and the ground pin 121 .

[0038] Specifically, if Figure 1As shown, the conductive terminal 111 is protruding along the first direction D1 on the surface of the functional chip 10 facing the lead frame 12, and one end of a portion of the conductive terminals 111 is electrically connected to the functional chip 10, and the other end is electrically connected to the ground pin 121 in the lead frame 12. The conductive connection layer 13 is located on the ground pin 121, and the conductive connection layer 13 and the conductive terminal 111 are arranged at intervals along the second direction D2, wherein the second direction D2 is parallel to the top surface of the lead frame 12. One end of the conductive connection layer 13 is electrically connected to the ground pin 121, and the other end is electrically connected to the electromagnetic shielding cover 16, so that not only can the signals of a portion of the conductive terminals 111 be led out through the lead frame 12, but also the signals in the conductive terminals 111 can be led out from the electromagnetic shielding cover 16 through the lead frame 12, thereby improving the design flexibility of the packaging structure and helping to expand the function of the packaging structure. At the same time, by connecting the ground pin 121 and the second platform portion 162 through the conductive connection layer 13 , the connection strength between the electromagnetic shielding cover 16 and the lead frame can be enhanced, thereby improving the overall structural stability of the packaging structure.

[0039] In one example, a first functional device can also be set on the second platform portion 162 to electrically connect the first functional device and the functional chip 10 through the second platform portion 162, the conductive connection layer 13, the ground pin 121 and a portion of the conductive terminals 111, thereby further expanding the function of the functional chip 10 and improving the integration of the packaging structure.

[0040] In some embodiments, the electromagnetic shielding cover 16 includes a first platform portion 161 located on the functional chip 10 and a second platform portion 162 located on the grounding pin 121, the conductive connection layer 13 electrically connects the second platform portion 162 and the grounding pin 121, and the size of the second platform portion 162 is smaller than the size of a portion of the conductive terminals 111.

[0041] Specifically, by providing the second platform portion 162 in the electromagnetic shielding cover 16, the contact area between the electromagnetic shielding cover 16 and the ground pin 121 can be increased, thereby reducing the contact resistance between the electromagnetic shielding cover 16 and the lead frame 12. The size of the second platform portion 162 is smaller than the size of a portion of the conductive terminals 111, thereby avoiding occupying too much area in the ground pin 121, thereby avoiding an increase in the size of the packaging structure.

[0042] In some embodiments, the functional chip 10 is a GaN chip, and the conductive terminal 111 electrically connected to the ground pin 121 is a source conductive terminal.

[0043] In some embodiments, the lead frame 12 further includes input / output pins 122 , and another portion of the conductive terminals 111 are located on the input / output pins 122 and electrically connected to the input / output pins 122 ;

[0044] The electromagnetic shielding cover 16 is located on the input / output pin 122 , and an insulating isolation layer 14 is provided between the electromagnetic shielding cover 16 and the input / output pin 122 .

[0045] In some embodiments, the electromagnetic shielding cover 16 further includes a third platform portion 163 . The third platform portion 163 and the second platform portion 162 are distributed on two opposite sides of the first platform portion 161 . The third platform portion 163 is located on the insulating isolation layer 14 .

[0046] Specifically, the electromagnetic shielding cover 16 includes the first platform portion 161, the second platform portion 162 and the third platform portion 163 distributed on opposite sides of the first platform portion 161 along the second direction D2, a first connecting portion connecting the first platform portion 161 and the second platform portion 162, and a second connecting portion connecting the first platform portion 161 and the third platform portion 163, so that the electromagnetic shielding cover 16 completely wraps the functional chip 10. In one example, both the first connecting portion and the second connecting portion are inclined connecting portions. The ground pin 121 in the lead frame 12 is electrically isolated from the input / output pin 122. One end of another number of the conductive terminals 111 is electrically connected to the functional chip 10, and the other end is electrically connected to the input / output pin 122, so that the signal in another number of the conductive terminals 111 can be led out through the input / output pin 122. The insulating isolation layer 14 is disposed between the input / output pin 122 and the third platform portion 163 for electrically isolating the third platform portion 163 from the input / output pin 122 .

[0047] In order to further increase the connection strength between the electromagnetic shielding cover 16 and the lead frame 12 and further reduce the cost of the packaging structure, in some embodiments, the conductive connection layer 13 is a conductive adhesive layer, and the insulating isolation layer 14 is an insulating adhesive layer.

[0048] Attached Figure 2 is a schematic diagram of another packaging structure in a specific embodiment of the utility model. In other embodiments, such as Figure 2As shown, the electromagnetic shielding cover 16 only includes the first platform portion 161, the second platform portion 162 located on one side of the first platform portion 161 along the second direction D2, and the first connecting portion connecting the first platform portion 161 and the second platform portion 162, that is, the electromagnetic shielding cover 16 only covers the functional chip 10 and the ground pin 121, and the input / output pin 122 is exposed to the outside of the electromagnetic shielding cover 16, so that the electromagnetic shielding cover 16 half wraps the functional chip 10. With the above structure, while simplifying the manufacturing process of the packaging structure and reducing the manufacturing cost of the packaging structure, signal crosstalk between different conductive terminals 111 is more effectively avoided.

[0049] In some embodiments, the packaging structure further includes:

[0050] The plastic sealing layer 17 at least covers the side walls of the electromagnetic shielding cover 16 , and the top surface of the plastic sealing layer 17 is flush with the top surface of the electromagnetic shielding cover 16 .

[0051] Specifically, the top surface of the plastic sealing layer 17 is flush with the top surface of the electromagnetic shielding cover 16, that is, the electromagnetic shielding cover 16 exposes the top surface of the plastic sealing layer 17, thereby facilitating the heat dissipation of the electromagnetic shielding cover 16. In one example, the plastic sealing layer 17 only covers the surface of the electromagnetic shielding cover 16 facing away from the functional chip 10, thereby further simplifying the manufacturing process of the packaging structure. In another example, the plastic sealing layer 17 includes a first plastic sealing layer located on the side of the electromagnetic shielding cover 16 facing the functional chip 10 and plastic sealing the functional chip 10 and the lead frame 12, and a second plastic sealing layer covering the surface of the electromagnetic shielding cover 16 facing away from the functional chip 10, and the first plastic sealing layer is flush with the surface of the lead frame facing away from the functional chip 10, and the top surface of the second plastic sealing layer is flush with the top surface of the electromagnetic shielding cover 16, thereby further improving the stability of the packaging structure.

[0052] The packaging structure provided in this specific embodiment, by providing a lead frame, a functional chip mounted on the lead frame, and an electromagnetic shielding cover covering the functional chip, shields the electromagnetic radiation in the external environment through the electromagnetic shielding cover, and prevents the functional chip from being affected by the external electromagnetic radiation, thereby ensuring the stability of the performance parameters of the functional chip, achieving improvement in the performance of the packaging structure, and also enabling the packaging structure to be applied in an electromagnetic radiation environment, thereby improving the reliability of the packaging structure and expanding the application field of the packaging structure. At the same time, by electrically connecting the electromagnetic shielding cover and the lead frame, and electrically connecting the functional chip and the lead frame, the signal of the functional chip can be led out through the lead frame and the electromagnetic shielding cover, breaking the limitation that the conductive terminal of the functional chip can only be led out from the bottom surface of the lead frame, thereby improving the design flexibility of the packaging structure and helping to expand the function of the packaging structure. Moreover, the electromagnetic shielding cover can also serve as a heat dissipation layer, so that the heat of the packaging structure can not only be dissipated from the lead frame to the lower part of the packaging structure, but also be dissipated from the upper part of the packaging structure through the electromagnetic shielding cover, avoiding heat accumulation inside the packaging structure, thereby improving the heat dissipation effect of the packaging structure.

[0053] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A packaging structure, characterized in that: include: Lead frame; A functional chip is located on the lead frame, and the functional chip is electrically connected to the lead frame; An electromagnetic shielding cover, located on the lead frame and covering the functional chip, the electromagnetic shielding cover being electrically connected to the lead frame; The heat-conducting adhesive layer is located on the surface of the functional chip away from the lead frame, one side of the heat-conducting adhesive layer is bonded to the functional chip, and the other side of the heat-conducting adhesive layer is bonded to the electromagnetic shielding cover.

2. The packaging structure according to claim 1, characterized in that: The electromagnetic shielding cover is a metal electromagnetic shielding cover.

3. The packaging structure according to claim 2, characterized in that: The functional chip has a plurality of conductive terminals on a surface facing the lead frame, the lead frame includes a ground pin, and a portion of the conductive terminals are located on the ground pin and electrically connected to the ground pin; The electromagnetic shielding cover is located on the grounding pin, and a conductive connection layer is provided between the electromagnetic shielding cover and the grounding pin.

4. The packaging structure according to claim 3, characterized in that: The electromagnetic shielding cover includes a first platform portion located on the functional chip and a second platform portion located on the ground pin, the conductive connection layer electrically connects the second platform portion and the ground pin, and the size of the second platform portion is smaller than the size of a portion of the conductive terminals.

5. The packaging structure according to claim 3, characterized in that: The functional chip is a GaN chip, and the conductive terminal electrically connected to the ground pin is a source conductive terminal.

6. The packaging structure according to claim 4, characterized in that: The lead frame further includes input / output pins, and another portion of the conductive terminals are located on the input / output pins and electrically connected to the input / output pins; The electromagnetic shielding cover is located on the input / output pin, and an insulating isolation layer is provided between the electromagnetic shielding cover and the input / output pin.

7. The packaging structure according to claim 6, characterized in that: The electromagnetic shielding cover further includes a third platform portion, wherein the third platform portion and the second platform portion are disposed on two opposite sides of the first platform portion, and the third platform portion is located on the insulating isolation layer.

8. The packaging structure according to claim 6, characterized in that: The conductive connection layer is a conductive adhesive layer, and the insulating isolation layer is an insulating adhesive layer.

9. The packaging structure according to claim 1, characterized in that: Also includes: The plastic sealing layer at least covers the side walls of the electromagnetic shielding cover, and the top surface of the plastic sealing layer is flush with the top surface of the electromagnetic shielding cover.

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