Electronic package and thermally conductive structure thereof
By using a thermally conductive structure of graphite sheets and nano-copper in semiconductor packaging, the problems of poor heat dissipation and adhesives were solved, achieving efficient heat dissipation and structural stability while avoiding additional costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SILICONWARE PRECISION IND CO LTD
- Filing Date
- 2025-05-16
- Publication Date
- 2026-05-29
AI Technical Summary
In existing technologies, semiconductor wafers have poor heat dissipation, which prevents heat from being effectively dissipated, potentially damaging the wafer and reducing product reliability. Furthermore, traditional adhesives are prone to slipping off during high-temperature processes or causing pinholes and cracks in the solder interface.
The thermally conductive structure uses graphite sheets as the intermediate layer and nanoporous metal layers (such as nano-copper) as the nanolayers. The heat sink is combined with electronic components using hot-press bonding technology. Graphite sheets have high thermal conductivity and compressibility, while nano-copper has a high thermal conductivity, thus avoiding the use of polymer adhesives.
It improves heat dissipation efficiency, avoids structural cracking or delamination caused by external forces or thermal stress, achieves efficient heat dissipation, and does not require additional new materials or manufacturing process costs.
Smart Images
Figure CN224306299U_ABST
Abstract
Description
Technical Field
[0001] This application relates to a semiconductor device, and more particularly to an electronic package and its thermally conductive structure. Background Technology
[0002] As electronic products demand higher functionality and processing speeds, semiconductor chips, as core components of these products, need to have higher density electronic circuits and components. Consequently, semiconductor chips generate a greater amount of heat during operation. Furthermore, the encapsulating colloids traditionally used to cover these semiconductor chips are poor heat transfer materials with a thermal conductivity of only 0.8 W / mk (i.e., poor heat dissipation efficiency). Therefore, if the heat generated by the semiconductor chip cannot be effectively dissipated, it will cause damage to the semiconductor chip and product reliability issues.
[0003] Therefore, in order to quickly dissipate heat to the outside, the industry usually equips semiconductor packages with heat sinks. These heat sinks are typically bonded to the back of the semiconductor chip through a heat dissipation material, such as a thermal interface material (TIM), so that the heat generated by the semiconductor chip can be dissipated through the heat dissipation material and the heat sink. Furthermore, the top surface of the heat sink is usually exposed to the encapsulation colloid or directly exposed to the atmosphere to achieve better heat dissipation.
[0004] Figure 1 This is a cross-sectional schematic diagram of an existing semiconductor package 1. The existing semiconductor package 1 first mounts a semiconductor wafer 12 onto a packaging substrate 11 using a flip-chip bonding method. Then, a heat sink 13 is bonded to the back side of the semiconductor wafer 12 via a thermally conductive interface material (TIM) 14. When a low-melting-point thermally conductive interface material 14 (e.g., indium metal sheet) is typically used on the back side of the semiconductor wafer 12, a back side metal layer (BSM) 15 must be applied to the back side of the semiconductor wafer 12. This BSM 15 can be composed of multiple metal layers. However, after installing the low-melting-point thermally conductive interface material 14, before entering the high-temperature processing stage, it is easily affected by machine operation, causing the low-melting-point thermally conductive interface material 14 to slip off or overflow from the edge of the back side of the semiconductor wafer 12. This results in insufficient coverage of the thermally conductive interface material 14 between the heat sink 13 and the semiconductor wafer 12, reducing the heat dissipation capacity of the semiconductor package, leading to poor heat dissipation performance, or even damage to electronic products.
[0005] To address this, the current industry solution involves using polymer adhesive to bond the back metal layer and the thermal interface material. However, the polymer adhesive hinders the reaction of metal ions during the bonding process between the low-melting-point thermal interface material and the back metal layer, resulting in holes and cracks at the welded interface and reducing the heat dissipation effect.
[0006] Therefore, overcoming the problems of the existing technology has become an urgent issue that needs to be addressed. Utility Model Content
[0007] In view of the various deficiencies of the prior art, this application provides a thermally conductive structure disposed between an electronic component and a heat sink, comprising: an intermediate layer; and a nanolayer disposed on at least one side of the intermediate layer.
[0008] This application also provides an electronic package, comprising: a carrier; an electronic component disposed on the carrier; a thermally conductive structure including an intermediate layer and a nanolayer disposed on at least one side of the intermediate layer; and a heat dissipation component bonded to the electronic component with respect to the thermally conductive structure.
[0009] This application also provides a method for manufacturing an electronic package, comprising: providing a carrier and disposing an electronic component on the carrier; providing a heat sink and a thermally conductive structure, wherein the thermally conductive structure includes an intermediate layer and a nanolayer disposed on at least one side of the intermediate layer; and attaching the heat sink to the electronic component across the thermally conductive structure.
[0010] In the aforementioned electronic packaging component and its thermally conductive structure and manufacturing method, the intermediate layer is a graphite sheet. The nanolayer is a nanoporous metal layer. The nanoporous metal layer is nano-copper. The nanolayer is disposed on opposite sides of the intermediate layer.
[0011] In the aforementioned electronic packaging component and its thermally conductive structure and manufacturing method, a metal layer is further provided between the intermediate layer and the nanolayer. The metal layer is gold or silver.
[0012] In the aforementioned electronic package and its thermally conductive structure and manufacturing method, the electronic component has opposing active and non-active surfaces, and the electronic component is placed on the carrier with the active surface and electrically connected to the carrier. A back metal layer is formed on the non-active surface of the electronic component.
[0013] In the aforementioned electronic package and its thermal conductive structure and manufacturing method, the heat sink includes a body and a support portion extending outward from the surface of the body, and the support portion of the heat sink is attached to the carrier through an adhesive layer.
[0014] In the aforementioned electronic package and its thermal conductive structure and manufacturing method, the thermal conductive structure combines the heat sink and the electronic component through thermo-press bonding technology.
[0015] The implementation of this application mainly provides a thermally conductive structure comprising an intermediate layer and a nanolayer disposed on at least one side of the intermediate layer. The intermediate layer is a graphite sheet, and the nanolayer is a nanoporous metal layer (nanocopper). Because the graphite sheet has high thermal conductivity and high compressibility, it can effectively fill and flatten the surface roughness between electronic components and heat sinks. The compressed graphite sheet can reduce thermal resistance. Furthermore, the nanocopper has a thermal conductivity as high as 340 W / mK, and its loose structure can meet the conditions for thermo-press bonding. At the same time, both the graphite sheet and the nanocopper are very soft and will not be affected by external forces or thermal stress deformation, thus avoiding problems such as reduced heat dissipation efficiency caused by the use of polymer adhesives. Attached Figure Description
[0016] Figure 1 This is a cross-sectional schematic diagram of an existing semiconductor package.
[0017] Figures 2A to 2D This is a cross-sectional schematic diagram of the electronic package and its thermal conductive structure and manufacturing method according to this application.
[0018] Explanation of reference numerals in the attached figures
[0019] 1 Semiconductor package
[0020] 11 Packaging substrate
[0021] 12 Semiconductor wafers
[0022] 13 Heat sink
[0023] 14 Thermally conductive interface material
[0024] 15 Crystal back metal layer
[0025] 2 Electronic Packages
[0026] 21. Bearing components
[0027] 22 Electronic components
[0028] 22a Working surface
[0029] 22b Non-operating surface
[0030] 220 conductive bump
[0031] 23 Heat sink
[0032] 231 Ontology
[0033] 232 Support section
[0034] 24 Thermally conductive structure
[0035] 241 Intermediate Layer
[0036] 242 nanometer layer
[0037] 25. Crystal back metal layer. Detailed Implementation
[0038] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification.
[0039] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the scope of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this application, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms such as "above," "first," "second," and "a" used in this specification are merely for clarity of description and are not intended to limit the scope of this application. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this application's implementation.
[0040] Please see Figures 2A to 2D This is a cross-sectional schematic diagram of the electronic package and its thermal conductive structure and manufacturing method of this application.
[0041] like Figure 2A As shown, a carrier 21 is provided, and an electronic component 22 is attached to the carrier 21.
[0042] The carrier 21 can be, for example, a substrate with a core layer and a circuit structure, or a coreless circuit structure, which includes a dielectric layer and a circuit layer (such as a redistribution layer). Alternatively, the carrier 21 can also be a lead frame, a silicon interposer, a wafer, or other board with metal routing, and is not limited to the above.
[0043] The electronic component 22 is mounted on the carrier 21 and electrically connected to the circuit layer. The electronic component 22 can be an active component, a passive component, a package structure, or a combination thereof. The active component can be a semiconductor wafer, while the passive component can be, for example, a resistor, capacitor, or inductor. In this embodiment, the electronic component 22 is a semiconductor wafer having opposing active surfaces 22a and non-active surfaces 22b, and the active surface 22a is electrically connected to the carrier 21 via multiple conductive bumps 220 using a flip-chip method.
[0044] In addition, a back metal layer 25 is provided on the non-functional surface 22b of the electronic component 22 to facilitate the subsequent bonding of the electronic component 22 with the heat sink. The back metal layer 25 can be a multilayer metal structure, such as one of the groups consisting of aluminum (Al), titanium (Ti), nickel (Ni), vanadium (V) and gold (Au).
[0045] like Figure 2B As shown, a heat sink 23 and a heat-conducting structure 24 are provided.
[0046] The heat sink 23 includes a body 231 and a support portion 232 extending outward from the surface of the body 231. The material of the heat sink 23 is, for example, copper.
[0047] The thermally conductive structure 24 is, for example, a thermally conductive interface material (TIM) structure, which includes an intermediate layer 241 and a nanolayer 242 disposed on at least one side of the intermediate layer 241, preferably with nanolayers 242 formed on opposite sides of the intermediate layer 241. In this embodiment, the intermediate layer 241 is a graphite sheet. Because graphite sheets have high thermal conductivity and high compressibility, they can effectively fill and flatten the surface roughness between the heat source (electronic component 22) and the heat sink 23, and the compressed graphite sheet can reduce thermal resistance, thus it can be used as a good thermally conductive interface material. In this embodiment, the nanolayer 242 is a nanoporous metal layer (e.g., nano-copper (Nano Porous Cu, NP-Cu)). It can be grown on the graphite sheet by coating a metal layer (e.g., gold or silver) on both sides of the graphite sheet to increase conductivity, and then growing nano-copper on the graphite sheet by electroplating. The nanoporous metal layer is not a solid structure, but has multiple pores and a thermal conductivity as high as 340 W / mK (e.g., nano-copper), which can effectively dissipate heat.
[0048] like Figure 2C As shown, the heat sink 23 is covered and attached to the electronic component 22 by the heat-conducting structure 24.
[0049] In this embodiment, thermal compression bonding (TCB) technology can be used to bond the heat sink 23 to the electronic component 22 by using a high temperature of 150-250°C and a pressure of 10-20 MPa.
[0050] like Figure 2DAs shown, the heat sink 23 is bonded to one side of the thermally conductive structure 24 and the electronic component 22 (crystal back metal layer 25) is bonded to the other side by the aforementioned thermo-press bonding technology. At the same time, the support portion 232 of the heat sink 23 is attached to the carrier 21 by an adhesive layer, so that the heat sink 23 is erected on the carrier 21 and contacts the electronic component 22 with the thermally conductive structure 24 in between, thereby obtaining the electronic package 2 of this application.
[0051] This application also discloses an electronic package 2, which includes: a carrier 21; an electronic component 22 having an opposing active surface 22a and a non-active surface 22b, wherein the electronic component 22 is attached to the carrier 21 with the active surface 22a and is electrically connected to the carrier 21, and a crystal back metal layer 25 is formed on the non-active surface 22b; a thermally conductive structure 24 including an intermediate layer 241 and a nanolayer 242 disposed on at least one side of the intermediate layer 241; and a heat sink 23, which is attached to the electronic component 22 through the thermally conductive structure 24.
[0052] The thermally conductive structure 24 is a thermally conductive interface material (TIM) structure, the intermediate layer 241 is a graphite sheet, and the nanolayer 242 is a nanoporous metal layer (e.g., nano-copper).
[0053] The heat sink 23 includes a body 231 and a support portion 232 extending outward from the surface of the body 231, so that the heat-conducting structure 24 is attached to the body 231 of the heat sink 23 on one side and to the electronic component 22 (crystal back metal layer 25) on the other side. At the same time, the support portion 232 of the heat sink 23 is attached to the carrier 21 through an adhesive layer, so that the heat sink 23 is erected on the carrier 21 and contacts the electronic component 22 through the heat-conducting structure 24.
[0054] In summary, the electronic package and its thermally conductive structure of this application mainly provide a thermally conductive structure comprising an intermediate layer and a nanolayer disposed on at least one side of the intermediate layer. The intermediate layer is a graphite sheet, and the nanolayer is a nanoporous metal layer (nano-copper). Because the graphite sheet has high thermal conductivity and high compressibility, it can effectively fill and flatten the surface roughness between electronic components and heat sinks. Furthermore, the compressed graphite sheet can reduce thermal resistance. The nano-copper, with a thermal conductivity as high as 340 W / mK and a loose structure that allows for thermo-press bonding, and because both the graphite sheet and the nano-copper are very flexible, they are not susceptible to cracking or delamination due to external forces or thermal stress deformation. This avoids problems such as reduced heat dissipation efficiency caused by the use of polymer adhesives. In addition, the aforementioned structure does not require the development of new processes and materials or the purchase of new equipment. Existing materials, processes, and equipment can solve existing technological problems in the industry, thus avoiding significant additional cost expenditures.
[0055] The above embodiments are used to illustrate the principles and effects of this application, and are not intended to limit this application. Those skilled in the art can modify the above embodiments without departing from the spirit and scope of this application. Therefore, the scope of protection of this application should be as set forth in the claims.
Claims
1. A heat-conducting structure disposed between an electronic component and a heat sink, characterized in that, include: Intermediate layer; as well as A nanolayer is disposed on at least one side of the intermediate layer.
2. The thermally conductive structure as described in claim 1, characterized in that, The intermediate layer is a graphite sheet.
3. The thermally conductive structure as described in claim 1, characterized in that, This nanolayer is a nanoporous metal layer.
4. The thermally conductive structure as described in claim 3, characterized in that, The nanoporous metal layer is nano-copper.
5. The thermally conductive structure as described in claim 1, characterized in that, The nanolayers are located on opposite sides of the intermediate layer.
6. The thermally conductive structure as described in claim 1, characterized in that, A metal layer is also provided between the intermediate layer and the nanolayer.
7. The thermally conductive structure as described in claim 6, characterized in that, The metal layer is gold or silver.
8. An electronic package, characterized in that, include: Load-bearing components; Electronic components are mounted on this carrier. A thermally conductive structure comprising an intermediate layer and a nanolayer disposed on at least one side of the intermediate layer; as well as The heat sink is integrated into the electronic component through the thermally conductive structure.
9. The electronic package as claimed in claim 8, characterized in that, The intermediate layer is a graphite sheet.
10. The electronic package as claimed in claim 8, characterized in that, This nanolayer is a nanoporous metal layer.
11. The electronic package as claimed in claim 10, characterized in that, The nanoporous metal layer is nano-copper.
12. The electronic package as claimed in claim 8, characterized in that, The nanolayers are located on opposite sides of the intermediate layer.
13. The electronic package as claimed in claim 8, characterized in that, A metal layer is also provided between the intermediate layer and the nanolayer.
14. The electronic package as claimed in claim 13, characterized in that, The metal layer is gold or silver.
15. The electronic package as claimed in claim 8, characterized in that, The electronic component has an opposing active surface and a non-active surface, and the electronic component is placed on the carrier with the active surface and is electrically connected to the carrier.
16. The electronic package as claimed in claim 15, characterized in that, A back metal layer is formed on the non-functional surface of the electronic component.
17. The electronic package as claimed in claim 8, characterized in that, The heat sink includes a body and a support portion extending outward from the surface of the body, and the support portion of the heat sink is attached to the carrier by an adhesive layer.