Electronic package

Abstract

An electronic package includes a bearing structure, an electronic component disposed on the bearing structure, a heat dissipation structure disposed on the electronic component through a heat conduction interface material, a back side metal disposed on the electronic component and connected with the heat conduction interface material, and a conductive adhesive disposed between the heat conduction interface material and the back side metal. Therefore, the surface viscosity of the conductive adhesive is utilized to limit the displacement of the heat-conducting interface material relative to the back side metal, and the heat dissipation efficiency of the electronic package is prevented from being affected by poor combination of the heat dissipation structure and the electronic element due to the offset of the heat-conducting interface material.

Description

Technical Field

[0001] The present application relates to an electronic package, and more particularly to an electronic package with a heat dissipation structure. Background Art

[0002] With the rise and rapid development of various applications and technologies that require high-speed computing, such as e-sports games, high-resolution audio and video multimedia, and autonomous driving, as well as the demand for miniaturization of related equipment, the number of components contained in semiconductor chips (ICs) using packaging structures such as flip chip ball grid array (FCBGA) is not only increasing, but the processing and computing speeds are also getting faster and faster, making the heat generated therein more and more considerable, and the requirements for heat dissipation structures are also getting higher and higher.

[0003] Figure 1 1 is a cross-sectional view of a conventional semiconductor package 1 . The semiconductor package 1 includes a package substrate 11 , a semiconductor chip 12 mounted on the upper side of the package substrate 11 in a flip-chip manner, and a heat sink 13 .

[0004] The heat sink 13 is made of copper, and the semiconductor chip 12 is made of silicon. To enhance the bonding and heat dissipation effects between the heat sink 13 and the semiconductor chip 12, the industry usually adds a back side metal (BSM) 15 and a thermal interface material (TIM) 14 on the back of the semiconductor chip 12. Considering that the indium metal sheet has a thermal conductivity of up to 86W / mK and its softness can withstand the thermal stress generated during the operation of the product, the semiconductor industry often uses indium metal sheets as the thermal interface material 14.

[0005] In addition, as the demand for thinner products continues, the thickness and weight of the indium metal sheet are also constantly decreasing, which leads to new challenges in packaging technology. For example, in order to prevent the thin indium metal sheet from being unable to perfectly align with the position of the semiconductor chip 12 during the packaging operation or even being blown away from the product surface by the airflow of the production line pipeline, a layer of adhesive 16 is applied between the thermal conductive interface material 14 and the back-side metal plating 15 to fix it.

[0006] However, semiconductor packages will warp during reliability thermal cycle tests, so no matter how much adhesive is used, it will be squeezed into the inner edge of the indium metal sheet, resulting in incomplete volatilization. Furthermore, the adhesive is composed of polymer materials, which will form an obstacle when the indium metal sheet is bonded to the back metal, not only resulting in incomplete bonding, but also causing loss of heat dissipation performance.

[0007] Therefore, how to overcome the above-mentioned problems of the prior art has become a topic that needs to be solved urgently. Utility Model Content

[0008] In view of the various deficiencies of the above-mentioned prior art, the present application provides an electronic package, comprising: a supporting structure; an electronic component, disposed on the supporting structure; a heat dissipation structure, disposed on the electronic component; a thermally conductive interface material, through which the heat dissipation structure is connected to the electronic component; a back metal, disposed on the electronic component and connected to the thermally conductive interface material; and a conductive adhesive, disposed between the thermally conductive interface material and the back metal, and containing a metal filler.

[0009] In the aforementioned electronic package, the electronic component has an active surface and an inactive surface opposite to each other, and the active surface is electrically connected to the supporting structure through a plurality of conductive bumps in a flip chip manner.

[0010] In the aforementioned electronic package, the heat dissipation structure has a top sheet and a supporting leg, one end of the supporting leg is connected to the top sheet, and the other end is arranged on the supporting structure, so that the bottom surface of the top sheet is opposite to the top surface of the electronic component.

[0011] In the aforementioned electronic package, the thermally conductive interface material is liquid metal, metal layer or colloid with thermal conductivity.

[0012] In the aforementioned electronic package, the thermally conductive interface material is an indium metal layer.

[0013] In the aforementioned electronic package, the back metal comprises at least one of an aluminum layer, a titanium layer, a chromium layer, a nickel layer, a nickel-vanadium alloy layer and a copper layer.

[0014] In the aforementioned electronic package, the distribution area of ​​the conductive adhesive accounts for at most 1% of the distribution area of ​​the back metal.

[0015] In the aforementioned electronic package, the metal filler has a first thermal conductivity coefficient, the thermally conductive interface material has a second thermal conductivity coefficient, and the first thermal conductivity coefficient is smaller than the second thermal conductivity coefficient.

[0016] In the aforementioned electronic package, the conductive adhesive is used as a fixing material between the thermal conductive interface material and the back metal.

[0017] In the aforementioned electronic package, the conductive adhesive has viscosity that can limit the displacement of the thermal conductive interface material relative to the back metal.

[0018] In the aforementioned electronic packaging component, the conductive adhesive is a composite material of a polymer adhesive and a metal filler.

[0019] Through the implementation of this application, the conductive adhesive is mainly arranged between the thermal interface material and the back metal. Since the conductive adhesive has viscosity, it can limit the displacement of the thermal interface material relative to the back metal, so as to avoid the poor combination of the heat dissipation structure and the electronic components caused by the displacement of the thermal interface material in the subsequent process, thereby affecting the heat dissipation efficiency of the electronic package. Furthermore, the conductive adhesive is a composite material of polymer adhesive and metal filler, which can not only achieve the effect of shaping and adhesion, but also the metal filler therein can make up for the problem of thermal impedance generated by the polymer adhesive, so that the heat source can transfer heat to the outside through the dense tiny metal filler. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional schematic diagram of a conventional semiconductor package.

[0021] Figure 2 It is a cross-sectional schematic diagram of the electronic package of the present application.

[0022] Figure 3 for Figure 2 A partial enlarged schematic diagram of .

[0023] Main component symbols

[0024] 1 Semiconductor Package

[0025] 11 Package substrate

[0026] 12 Semiconductor Chip

[0027] 13 Heat sink

[0028] 14 Thermal Interface Materials

[0029] 15 Back Metal

[0030] 16 Adhesive layer

[0031] 2 Electronic packaging

[0032] 21 Load-bearing structure

[0033] 22 Electronic components

[0034] 22a Active surface

[0035] 22b Non-active surface

[0036] 220 Conductive bump

[0037] 23 Heat dissipation structure

[0038] 231 Top sheet

[0039] 232 Support feet

[0040] 24 Thermal Interface Materials

[0041] 25 Back Metal

[0042] 26 Conductive adhesive

[0043] 260 Polymer Adhesive

[0044] 261Metal fillings. DETAILED DESCRIPTION

[0045] The following describes the implementation methods of the present application through specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification.

[0046] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings attached to this specification are only used to match the contents disclosed in the specification for the understanding and reading of those skilled in the art, and are not used to limit the limiting conditions for the implementation of this application, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects and purposes that can be achieved by this application, should still fall within the scope of the technical contents disclosed in this application. At the same time, the terms such as "on", "first", "second", and "one" cited in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of this application. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of this application without substantially changing the technical contents.

[0047] Figure 2 The electronic package 2 of the present application is a cross-sectional schematic diagram. The electronic package 2 of the present embodiment includes: a supporting structure 21; an electronic component 22, which is disposed on the supporting structure 21 and electrically connected to the supporting structure 21; a heat dissipation structure 23, which is disposed on the electronic component; a thermal interface material (TIM) 24, through which the heat dissipation structure 23 is connected to the electronic component 22; a back metal 25, which is disposed on the electronic component 22 and connected to the thermal interface material 24; and a conductive adhesive 26, which is disposed between the thermal interface material 24 and the back metal 25, wherein the conductive adhesive 26 has a metal filler 261 (such as Figure 3 shown).

[0048] The aforementioned supporting structure 21 is, for example, a packaging substrate (substrate) having a core layer and a circuit structure or a coreless circuit structure, which forms a circuit layer on a dielectric material, such as a redistribution layer (RDL for short), and can also be a lead frame, a silicon interposer, a wafer, or other boards with metal routing, etc., but is not limited to the above.

[0049] The aforementioned electronic component 22 is mounted on the supporting structure 21 and electrically connected to the circuit layer. The electronic component 22 may be an active component, a passive component, a packaging structure or a combination thereof. The active component may be an application processor (AP) or other semiconductor chip such as a computing chip used in a mobile device such as a mobile phone, while the passive component may be, for example, a resistor, a capacitor, and an inductor. In the present embodiment, the electronic component 22 is a semiconductor chip having an active surface 22a and an inactive surface 22b opposite to each other, and the active surface 22a is electrically connected to the supporting structure 21 through a plurality of conductive bumps 220 in a flip chip manner.

[0050] The heat dissipation structure 23 is, for example, a heat sink, a heat dissipation cover (Lid) or other components or structures with equivalent functions. In this embodiment, the heat dissipation structure 23 has a top sheet 231 and a support leg 232. One end of the support leg 232 is connected to the top sheet 231, and the other end is disposed on the supporting structure 21, so that the bottom surface of the top sheet 231 is opposite to the top surface of the electronic component 22. In addition, the heat dissipation structure 23 is made of copper metal.

[0051] A thermally conductive interface material 24 is further provided between the top surface of the electronic component 22 and the bottom surface of the top sheet 231 of the heat dissipation structure 23 to more efficiently conduct the heat generated by the electronic component 22 to the heat dissipation structure 23 and then dissipate it into the environment. The thermally conductive interface material 24 is, for example, liquid metal, a metal layer, or a colloid with thermal conductivity, and the thermally conductive interface material 24 can be liquefied when heated and pressurized. In this embodiment, the thermally conductive interface material 24 is, for example, an indium metal layer.

[0052] The back metal 25 is disposed on the electronic element 22 and connected to the thermally conductive interface material 24. The back metal 25 may be a multi-layer metal layer structure, for example, including at least one of an aluminum layer, a titanium layer, a chromium layer, a nickel layer, a nickel-vanadium alloy layer, and a copper layer.

[0053] Please also refer to Figure 3 , the conductive adhesive 26 is disposed between the thermally conductive interface material 24 and the back metal 25. The conductive adhesive 26 serves as a fixing material between the thermally conductive interface material 24 and the back metal 25, wherein the conductive adhesive 26 has viscosity to limit the displacement of the thermally conductive interface material 24 relative to the back metal 25. In this embodiment, the conductive adhesive 26 is a composite material of a polymer adhesive 260 (such as silica gel) and a metal filler (metal particles) 261, which can not only achieve the effects of shaping and adhesion, but also the metal filler 261 can make up for the problem of thermal impedance generated by the polymer adhesive 260, allowing the heat source to transfer heat through the dense tiny metal fillers 261.

[0054] In one embodiment, the metal filler 261 accounts for at least 88.5% to 89% of the weight of the conductive adhesive 26 .

[0055] In one embodiment, the metal filler 261 has a first thermal conductivity, and the thermally conductive interface material 24 has a second thermal conductivity. For example, the first thermal conductivity is smaller than the second thermal conductivity.

[0056] In this embodiment, the distribution area of ​​the conductive adhesive 26 accounts for at most 1% (preferably 0.5%) of the distribution area of ​​the back metal 25 .

[0057] In summary, the electronic package of the present application mainly places the conductive adhesive between the thermal interface material and the back metal. The conductive adhesive has viscosity and can limit the displacement of the thermal interface material relative to the back metal, thereby preventing the thermal interface material from being offset in the subsequent process, resulting in poor integration between the heat dissipation structure and the electronic components, and affecting the heat dissipation efficiency of the electronic package. Furthermore, the conductive adhesive is a composite material of a polymer adhesive and a metal filler, which can not only achieve the effects of shaping and adhesion, but also the metal filler therein can make up for the problem of thermal impedance generated by the polymer adhesive, allowing the heat source to transfer heat to the outside through dense tiny metal fillers.

[0058] The above embodiments are used to illustrate the principles and effects of the present application, but are not used to limit the present application. Any person skilled in the art may modify the above embodiments without violating the spirit and scope of the present application. Therefore, the scope of protection of the present application should be as listed in the claims.

Claims

1. An electronic package, characterized in that: include: load-bearing structure; An electronic component is disposed on the supporting structure; A heat dissipation structure is provided on the electronic component; A thermally conductive interface material, through which the heat dissipation structure is connected to the electronic component; A back metal is disposed on the electronic component and connected to the thermally conductive interface material; as well as The conductive adhesive is disposed between the thermal conductive interface material and the back metal and contains metal fillers.

2. The electronic package according to claim 1, wherein: The electronic component has an active surface and an inactive surface opposite to each other, and the active surface is electrically connected to the supporting structure through a plurality of conductive bumps in a flip chip manner.

3. The electronic package according to claim 1, wherein: The heat dissipation structure has a top sheet and a supporting foot. One end of the supporting foot is combined with the top sheet, and the other end is arranged on the bearing structure, so that the bottom surface of the top sheet is opposite to the top surface of the electronic component.

4. The electronic package according to claim 1, wherein: The thermally conductive interface material is liquid metal, metal layer or colloid with thermal conductivity.

5. The electronic package according to claim 1, wherein: The thermal conductive interface material is an indium metal layer.

6. The electronic package according to claim 1, wherein: The back metal includes at least one of an aluminum layer, a titanium layer, a chromium layer, a nickel layer, a nickel-vanadium alloy layer and a copper layer.

7. The electronic package according to claim 1, wherein: The distribution area of ​​the conductive adhesive accounts for at most 1% of the distribution area of ​​the back metal.

8. The electronic package according to claim 1, wherein: The metal filler has a first thermal conductivity coefficient, the thermally conductive interface material has a second thermal conductivity coefficient, and the first thermal conductivity coefficient is smaller than the second thermal conductivity coefficient.

9. The electronic package according to claim 1, wherein: The conductive adhesive is used as a fixing material between the thermal conductive interface material and the back metal.

10. The electronic package according to claim 1, wherein: The conductive adhesive has viscosity and can limit the displacement of the thermal conductive interface material relative to the back metal.

11. The electronic package according to claim 1, wherein: The conductive adhesive is a composite material of a polymer adhesive material and a metal filler.

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