Package structure

Abstract

The embodiment of the utility model discloses a packaging structure. The packaging structure comprises an electronic component; a thermally conductive molding compound layer disposed around the electronic component to encapsulate the electronic component; the heat-conducting molding compound layer is arranged between the electronic component and the heat-dissipating cover, the heat-dissipating cover is provided with a surface facing the heat-conducting molding compound layer and a groove recessed into the surface, and the groove is used for accommodating at least one part of the heat-conducting molding compound layer. According to the technical scheme, at least heat generated by the electronic component can be promoted to be conducted.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and more specifically, to a packaging structure. Background Art

[0002] refer to Figure 1 As shown, a thermal interface material (TIM) 10 is disposed on an electronic component 20 and connected to a heat dissipation cover 30 to conduct heat generated by the electronic component 20. The composition of the conventional thermal interface material 10 includes thermally conductive particles 13 mixed with a polymer adhesive material. Since most of the thermally conductive particles 13 are spherical in shape with spherical side walls, after the thermally conductive particles 13 contact each other, there will be portions of the spherical side walls that cannot contact each other, resulting in gaps 15 between the thermally conductive particles 13. Since the spherical shape results in a small contact area, the thermal conductivity effect cannot be improved, and the thermal conductivity effect of the electronic component 20 needs to be further improved.

[0003] In other prior arts, Ag (silver) based thermal conductive interface materials can have higher thermal conductivity benefits. Specifically, sintering type Ag (flat plates, microparticles and nanoparticles, etc.) is mixed during the curing process to fill the gaps and voids between the thermal conductive particles. However, these special shapes / sizes of Ag are expensive materials, which makes Ag-based thermal conductive interface materials high-cost in terms of raw materials, resulting in high thermal conductive interface materials being too expensive, and sintering is not easy to control gaps or voids during the curing process. Cu (copper) is a cheaper material and has high thermal conductivity, but Cu material is very easy to oxidize during the assembly process. If Cu is used to improve the thermal conductivity of the thermal conductive interface material, there will be unreliability issues. Utility Model Content

[0004] In view of the above problems, the present application proposes a packaging structure that can at least promote the heat conduction of the heat generated by the electronic components.

[0005] According to one aspect of the present application, a packaging structure is provided, which includes: an electronic component; a thermally conductive molding material layer, which is arranged around the electronic component to encapsulate the electronic component; and a heat dissipation cover, wherein the thermally conductive molding material layer is arranged between the electronic component and the heat dissipation cover, wherein the heat dissipation cover has a surface facing the thermally conductive molding material layer and a groove recessed in the surface, and the groove is used to accommodate at least a portion of the thermally conductive molding material layer.

[0006] In some embodiments, the thermally conductive molding compound layer includes: a polymer material sublayer; and a plurality of metal nanowires, wherein the polymer material sublayer covers the plurality of metal nanowires.

[0007] In some embodiments, a thermal conductivity of a metal nanowire in the plurality of metal nanowires is greater than a thermal conductivity of the polymer material sublayer.

[0008] In some embodiments, the thermally conductive molding compound layer further includes: a plurality of filler particles coated by a polymer material sublayer; wherein the thermal conductivity of the metal nanowires in the plurality of metal nanowires is greater than the thermal conductivity of the filler particles.

[0009] In some embodiments, the filler particles have a thermal expansion coefficient that is closer to that of the electronic component than to that of the plurality of metal nanowires.

[0010] In some embodiments, at least two metal nanowires among the plurality of metal nanowires are in contact with each other, wherein a width of a contact surface of the at least two metal nanowires is greater than a diameter of one metal nanowire among the at least two metal nanowires.

[0011] In some embodiments, corresponding two end portions of at least two metal nanowires are not connected, and main bodies of at least two metal nanowires are in contact with each other.

[0012] In some embodiments, at least one metal nanowire in the plurality of metal nanowires extends out from the groove.

[0013] In some embodiments, at least one metal nanowire has two ends and a main body located between the two ends, wherein the main body of the at least one metal nanowire contacts an inner wall of the groove.

[0014] According to another aspect of the present application, a packaging structure is provided, which includes: an electronic component; a molding material layer, which is arranged around the electronic component to encapsulate the electronic component; a plurality of metal nanowires, which are coated by the molding material layer, at least one of the plurality of metal nanowires extends from the inner wall of the groove; and a heat dissipation cover, wherein the molding material layer is arranged between the electronic component and the heat dissipation cover, wherein the heat dissipation cover has a surface facing the thermally conductive molding material layer and a groove recessed in the surface, and the groove is used to accommodate at least a portion of the thermally conductive molding material layer.

[0015] In the above-mentioned packaging structure, by providing a thermally conductive molding plastic layer and providing a groove in the heat dissipation cover to accommodate part of the thermally conductive molding plastic layer, the heat conduction of the heat generated by the electronic components can be further promoted; and, since the thermally conductive molding plastic layer has good thermal conductivity, the heat dissipation cover can be thinned, thereby reducing the overall thickness of the packaging structure. By providing metal nanowires in the thermally conductive molding plastic layer, the thermally conductive molding plastic layer can have higher thermal conductivity than the existing molding plastic layer. Metal nanowires can fill the gaps and voids between filler particles, so that fewer gaps and voids can be obtained to improve the thermal conductivity efficiency. The contact surface between the metal nanowires has an irregular extended shape, and the contact area is increased by the non-curved contact area between the metal nanowires, further improving the thermal conductivity efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the enlarged details of the existing packaging structure and the thermal interface material therein.

[0018] Figure 2 is a schematic cross-sectional view of a packaging structure according to an embodiment of the present application.

[0019] Figure 3A is a schematic structural diagram of two metal nanowires in a thermally conductive molding compound layer in contact with each other according to an embodiment of the present application.

[0020] Figure 3B It is a schematic diagram of the structure in which a metal nanowire of a thermally conductive molding compound layer contacts an electronic component according to an embodiment of the present application.

[0021] Figure 4A is a schematic cross-sectional view of a packaging structure according to another embodiment of the present application.

[0022] Figure 4B It is a schematic structural diagram of the inner wall of the groove of the heat dissipation cover in which the metal nanowire contacts according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0024] The following disclosure provides many different embodiments or examples for realizing different features of the provided subject matter. Specific examples of components and arrangements will be described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component is formed between the first component and the second component so that the first component and the second component may not be in direct contact. Moreover, the present invention may repeatedly refer to numbers and / or letters in various examples. This repetition is only for simplicity and clarity, and does not itself represent the relationship between the various embodiments and / or configurations discussed.

[0025] In addition, the embodiments and features in the embodiments of the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] Figure 2 is a schematic cross-sectional view of a package structure 100 according to an embodiment of the present application. Figure 2 As shown, the packaging structure 100 may include an electronic component 120, a thermally conductive molding material layer 140, and a heat dissipation cover 190. The thermally conductive molding material layer 140 may be disposed around the electronic component 120 to encapsulate the electronic component 120. The thermally conductive molding material layer 140 may be disposed between the electronic component 120 and the heat dissipation cover 190. The thermally conductive molding material layer 140 may conduct the heat generated by the electronic component 120 to the heat dissipation cover 190 for heat dissipation. In some embodiments, the heat dissipation cover 190 may be made of a metal material. In some embodiments, the material of the electronic component 120 includes silicon. The heat dissipation cover 190 may have a surface 190u facing the thermally conductive molding material layer 140, and a groove 192 recessed into the surface 190u, and the groove 192 may be used to accommodate at least a portion of the thermally conductive molding material layer 140. Figure 2 In the illustrated embodiment, the top portion of the TMC layer 140 is located in the groove 192 of the heat dissipation cover 190. The groove 192 of the heat dissipation cover 190 contacts the top surface 140t of the TMC layer 140 and the top portion of the side surface 140s of the TMC layer 140.

[0027] In some embodiments, the thermally conductive molding material layer 140 may be formed by a molding material layer 142 surrounding and encapsulating the electronic component 120 and a plurality of metal nanowires 144. The plurality of metal nanowires 144 are located in the molding material layer 142 and are coated by the molding material layer 142. The material of the molding material layer 142 may be an existing molding material. Since the thermal conductivity of the metal nanowires 144 is higher than that of the molding material. Therefore, by providing the metal nanowires 144 in the thermally conductive molding material layer 140, the thermally conductive molding material layer 140 may have a higher thermal conductivity than the existing molding material layer 142. By using such a thermally conductive molding material layer 140 to coat the electronic component 120 to encapsulate the electronic component 120, the heat generated by the electronic component 120 may be facilitated to be conducted.

[0028] In addition, in the above-mentioned package structure 100, by providing the thermally conductive molding compound layer 140 and providing a groove 192 in the heat dissipation cover 190 to accommodate part of the thermally conductive molding compound layer 140, heat conduction to the electronic component 120 can be further promoted. In addition, since the thermally conductive molding compound layer 140 has good thermal conductivity, the heat dissipation cover 190 can be thinned, thereby reducing the overall thickness of the package structure 100.

[0029] In some embodiments, the TMC layer 140 contacts both the electronic component 120 and the heat dissipation cover 190. Since the TMC layer 140 has good thermal conductivity, the TMC layer 140 can be used as a thermal interface material between the electronic component 120 and the heat dissipation cover 190.

[0030] In some embodiments, the molding compound layer 142 may include a polymer sublayer 141 composed of a polymer material to serve as an adhesive material. The polymer sublayer 141 may coat a plurality of metal nanowires 144. In some embodiments using the existing molding compound layer 142, the polymer material of the polymer sublayer 141 may be, for example, epoxy resin. The molding compound layer 142 may also include a plurality of filler particles 143, which are also coated by the polymer sublayer 141. In some embodiments, the filler particles 143 may be silicon (Si) filler particles. In some embodiments, a plurality of metal nanowires 144 may extend between the plurality of filler particles 143. In some embodiments, at least two of the plurality of metal nanowires 144 may contact each other. In some embodiments, at least two of the plurality of metal nanowires 144 may be separated by the molding compound layer 142.

[0031] By disposing non-spherical metal nanowires 144 in the thermally conductive molding compound layer 140 , the metal nanowires 144 can fill the gaps and voids between the filler particles 143 , thereby obtaining fewer gaps and voids, thereby improving the thermal conductivity.

[0032] In some embodiments, the metal nanowire 144 is a Cu nanowire. The use of Cu nanowires can reduce the price of the thermal interface material. At the same time, the thermal conductivity can be compatible with and comparable to that of Ag. In addition, the oxidation resistance of Cu nanowires is better than that of ordinary copper wires, so the reliability of the thermal interface material is also improved.

[0033] In some embodiments, the thermal conductivity of the metal nanowires 144 may be greater than the thermal conductivity of the polymer material sublayer 141. In some embodiments, the thermal conductivity of the metal nanowires 144 may be greater than the thermal conductivity of the filler particles 143. In some embodiments, the thermal expansion coefficient of the filler particles 143 may be closer to the thermal expansion coefficient of the electronic component 120 than the metal nanowires 144.

[0034] Continue to refer Figure 2As shown, the bottom filler 162 covers the multiple electrical connectors 122 of the electronic component 120. The thermally conductive molding compound layer 140 can be further disposed around the bottom filler 162. The package structure 100 can also include a substrate 102 located below the heat dissipation cover 190. The electronic component 120 can be connected to the substrate 102 through the redistribution layer 104 and the electrical connector 106. Another bottom filler 164 covers the multiple electrical connectors 106 between the redistribution layer 104 and the substrate 102. A space for accommodating the electronic component 120, the thermally conductive molding compound layer 140, the redistribution layer 104, and the bottom filler 164 is defined between the heat dissipation cover 190 and the substrate 102.

[0035] Figure 2 The specific structure of the package structure 100 shown is only an example. In other embodiments, the package structure 100 may be other structures that use the thermally conductive molding compound layer 140 and the heat dissipation cover 190 to dissipate heat from the electronic component 120 .

[0036] Furthermore, since the metal nanowires 144 (e.g., Cu nanowires) are densely prepared, a large number of interconnections may exist between the plurality of metal nanowires 144, and a large number of contact points may be generated. Therefore, in some embodiments, at least two of the plurality of metal nanowires 144 may contact each other, as shown in FIG. Figure 3A As shown, two metal nanowires 144a and 144b in contact with each other are shown for illustration. In some embodiments, the width of the contact surface of the two metal nanowires 144a and 144b may be greater than the diameter of one metal nanowire among the at least two metal nanowires 144a and 144b.

[0037] The metal nanowire 144a has two ends 144a1, 144a2, and a main body 144a3 between the two ends 144a1, 144a2. The metal nanowire 144b has two ends 144b1, 144b2, and a main body 144b3 between the two ends 144b1, 144b2. The corresponding two ends 144a1, 144b1 of the two metal nanowires 144a, 144b are not connected. The main bodies 144a3, 144b3 of the two metal nanowires 144a, 144b may contact each other. The end 144a2 of the metal nanowire 144a may contact the main body 144b3 or the end 144b2 of another metal nanowire 144b. In some embodiments, the two metal nanowires 144a, 144b may contact each other discontinuously. In other embodiments, the main bodies 144a3 and 144b3 of the two metal nanowires 144a and 144b may be in continuous contact. In some other embodiments, at least two metal nanowires in the plurality of metal nanowires 144 may contact each other in any other possible manner. In some embodiments, the contact surface between the two metal nanowires 144a and 144b may have an irregularly extended shape, that is, the contact surface may be a non-curved contact area.

[0038] In the embodiment of the present application, the molding compound layer 142 (see FIG. 1 ) which currently has only spherical filler particles 143 is improved by providing non-spherical metal nanowires 144. Figure 2 ), the contact area can be increased by utilizing the non-curved contact area between the metal nanowires 144, thereby further improving the thermal conductivity.

[0039] refer to Figure 3B As shown, one metal nanowire 144c among the plurality of metal nanowires 144 may contact the sidewall 120s of the electronic component 120. Figure 3B In the example shown, the main body 144c3 of the metal nanowire 144c contacts the side wall 120s of the electronic component 120, and the two end portions 144c1 and 144c2 of the metal nanowire 144c do not contact the side wall 120s of the electronic component 120. In some embodiments, the metal nanowire 144c may further contact one or more additional metal nanowires 144 (not shown). It should be understood that a greater number of metal nanowires 144 may contact the side wall 120s and / or the top surface of the electronic component 120. Figure 3B It is only taken as an example that one metal nanowire 144c contacts the sidewall 120c. In other embodiments, any portion of at least one metal nanowire among the plurality of metal nanowires 144 may contact the electronic component 120. In some embodiments, at least one metal nanowire among the plurality of metal nanowires 144 may contact the heat dissipation cover 190.

[0040] Figure 4A is a schematic cross-sectional view of a package structure 100 ′ according to another embodiment of the present application. Figure 4A Many aspects of the package structure 100 ′ shown can be compared with those of the above reference Figure 2 The package structure 100 described above is similar or identical, and only the following description is made of Figure 4A The package structure 100 ′ is shown to be different.

[0041] exist Figure 4A In the package structure 100' shown, the thermally conductive molding compound layer 140 may include a plurality of metal nanowires. Figure 4A A plurality of metal nanowires 144 are schematically shown in FIG. Figure 4A The dotted line frame in FIG. 4 shows the area 401 occupied by the groove 192 of the heat dissipation cover 190. At least one metal nanowire among the plurality of metal nanowires 144 extends out from the groove 192. Figure 4A In FIG. 4 , the plurality of metal nanowires 144 are shown to extend from the groove 192 . That is, a portion of each metal nanowire 144 extends beyond the region 401 occupied by the groove 192 .

[0042] refer to Figure 4B As shown, at least one metal nanowire 144d among the plurality of metal nanowires 144 may contact the inner wall 192w1 of the groove 192. Specifically, the metal nanowire 144d may have two end portions 144d1, 114d2, and a main body portion 144d3 located between the two end portions 144d1, 114d2. In some embodiments, any portion of the metal nanowire 144d may contact the vertically extending inner wall 192w1 of the groove 192. Figure 4B In the illustrated embodiment, the main body 144 d 3 of the metal nanowire 144 d contacts the inner wall 192 w 1 of the groove 192 .

[0043] exist Figure 4B In the illustrated embodiment, both ends 144c1, 144c2 of the metal nanowire 144c may not contact the laterally extending inner wall 192w1 of the groove 192. In some other embodiments, one end 144c2 of the metal nanowire 144c may contact the inner wall 192w2 of the groove 192.

[0044] Continue to refer Figure 4BAs shown, in some embodiments, at least one metal nanowire 144e among the plurality of metal nanowires 144 may extend from the inner wall 192w2 of the groove 192. The metal nanowire 144e may have two ends 114e1, 114e2, and a main body 144e3 located between the two ends 144e1, 114e2. The end 114e2 of the metal nanowire 144e may contact the laterally extending inner wall 192w2 of the groove 192, so that the metal nanowire 144e extends from the inner wall 192w2 of the groove 192. In some embodiments, the other end 144e1 of the metal nanowire 144e is outside the area 401 occupied by the groove 192. In some embodiments, the metal nanowire 144e may extend between the heat dissipation cover 190 and the electronic component 120. In some embodiments, the metal nanowire 144e may be connected to the electronic component 120 via other metal nanowires.

[0045] It should be understood that a greater number of metal nanowires 144 may be in contact with the inner wall 192w1 and / or 192w2 of the groove 192. Figure 4B The contact between the metal nanowires 144d and 144e and the inner walls 192w1 and 192w1 is merely taken as an example.

[0046] In summary, in the above-mentioned packaging structure, by providing a thermally conductive molding plastic layer and providing a groove in the heat dissipation cover to accommodate part of the thermally conductive molding plastic layer, the heat generated by the electronic components can be facilitated for heat conduction; and, since the thermally conductive molding plastic layer has good thermal conductivity, the heat dissipation cover can be thinned, thereby reducing the overall thickness of the packaging structure. By providing metal nanowires in the thermally conductive molding plastic layer, the thermally conductive molding plastic layer can have a higher thermal conductivity than the existing molding plastic layer. By providing non-spherical metal nanowires in the thermally conductive molding plastic layer, the metal nanowires can fill the gaps and voids between the filler particles, thereby obtaining fewer gaps and voids to improve the thermal conductivity efficiency. Since a large number of interconnections can exist between multiple metal nanowires, and the contact surface between the metal nanowires has an irregular extended shape, the non-spherical metal nanowires improve the molding plastic layer that currently only has spherical filler particles, and the contact area is increased by the non-curved contact area between the metal nanowires, further improving the thermal conductivity efficiency.

[0047] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A packaging structure, characterized in that: include: Electronic components; A thermally conductive molding compound layer, disposed around the electronic component to encapsulate the electronic component; The heat dissipation cover is provided between the electronic component and the heat dissipation cover, wherein the heat dissipation cover has a surface facing the heat conductive molding material layer and a groove recessed into the surface, and the groove is used to accommodate at least a part of the heat conductive molding material layer.

2. The packaging structure according to claim 1, characterized in that: The thermally conductive molding compound layer comprises: polymer material sublayer; A plurality of metal nanowires are provided, wherein the polymer material sublayer covers the plurality of metal nanowires.

3. The packaging structure according to claim 2, characterized in that: A thermal conductivity of a metal nanowire among the plurality of metal nanowires is greater than a thermal conductivity of the polymer material sublayer.

4. The packaging structure according to claim 2, characterized in that: The thermally conductive molding compound layer further comprises: a plurality of filler particles, coated by the polymer material sublayer; Wherein, the thermal conductivity of the metal nanowires among the plurality of metal nanowires is greater than the thermal conductivity of the filler particles.

5. The packaging structure according to claim 4, characterized in that: The filler particles have a thermal expansion coefficient that is closer to a thermal expansion coefficient of the electronic component than to a thermal expansion coefficient of the plurality of metal nanowires.

6. The packaging structure according to claim 2, characterized in that: At least two metal nanowires among the plurality of metal nanowires are in contact with each other, wherein a width of a contact surface of the at least two metal nanowires is greater than a diameter of one metal nanowire among the at least two metal nanowires.

7. The packaging structure according to claim 6, characterized in that: Corresponding two end portions of the at least two metal nanowires are not connected, and main body portions of the at least two metal nanowires are in contact with each other.

8. The packaging structure according to claim 2, characterized in that: At least one metal nanowire among the plurality of metal nanowires extends out from the groove.

9. The packaging structure according to claim 8, characterized in that: The at least one metal nanowire has two ends and a main body located between the two ends, wherein the main body of the at least one metal nanowire contacts an inner wall of the groove.

10. A packaging structure, characterized in that: include: Electronic components; A molding compound layer, disposed around the electronic component to encapsulate the electronic component; a plurality of metal nanowires, coated by the molding compound layer; A heat dissipation cover, wherein the molding material layer is arranged between the electronic component and the heat dissipation cover, wherein the heat dissipation cover has a surface facing the molding material layer and a groove recessed into the surface, the groove is used to accommodate at least a portion of the molding material layer, and at least one metal nanowire among the plurality of metal nanowires extends from an inner wall of the groove.

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