A heat dissipation advanced package structure accelerating air convection and a manufacturing method thereof

Abstract

This invention discloses an advanced heat dissipation packaging structure and its fabrication method for accelerating air convection. The method includes the following steps: First, after completing the chip core packaging, a first package body is covered on the outside of the chip using a molding process, and then ground until the back side of the chip is exposed. Second, a heat convection channel is prepared on the back side of the chip. Specifically, a wide-channel structure is formed by coating a molding material (such as silicone sealant) that can withstand the molding temperature using 3D printing technology, depositing a non-metallic heat insulation layer (such as SiO2), molding a second package body, and grinding until the molding material is exposed. Finally, the molding material is removed by dissolving it with a chemical solution, forming a heat convection channel that is thermally connected to the back side of the chip. This invention solves the technical problems of insufficient heat dissipation efficiency and inability to adapt to the thermal management requirements of high-density integrated chips in existing chip packaging structures, achieving a highly efficient and compact heat dissipation effect.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor packaging technology and relates to an advanced heat dissipation packaging structure for high-power chips (such as high-performance computing chips). It achieves efficient heat dissipation through the heat convection channels designed inside the package, overcoming the size and stress limitations of traditional heat dissipation methods. Background Technology

[0002] In existing semiconductor packaging technologies, heat dissipation is a key factor affecting chip performance and reliability. Currently, there are two main heat dissipation methods: 1. Top-mounted air cooling: Forced air cooling is achieved by adding a fan or heatsink to the top of the package. However, this method is bulky and cannot be used in thin and light devices (such as wearable devices), thus limiting its application scenarios.

[0003] 2. Backside Metal Thermal Conduction: A thick metal layer (such as copper) is plated on the back of the chip, and heat is conducted to the substrate using solder or thermal adhesive. However, the thick metal layer introduces significant stress, making it unsuitable for thin and large chip packages (such as high-performance computing chips or aluminum chips), which can easily lead to package deformation or failure.

[0004] The methods described above all have limitations and cannot meet the demands of modern electronic devices for high heat dissipation efficiency, miniaturization, and reliability. Therefore, there is an urgent need for a new type of heat dissipation packaging structure to achieve efficient thermal management within a limited space. Summary of the Invention

[0005] The purpose of this invention is to provide an advanced heat dissipation packaging structure and its manufacturing method that accelerates air convection, aiming to solve the technical problems of insufficient heat dissipation efficiency of existing chip packaging structures and their inability to adapt to the thermal management requirements of high-density integrated chips.

[0006] The objective of this invention is achieved through the following technical solution: A method for fabricating an advanced heat dissipation packaging structure that accelerates air convection includes the following steps: S1. After completing the core packaging process of the chip, a first package body is covered on the outside of the chip using a molding process, and the surface of the first package body is ground until the back of the chip is completely exposed. S2. Fabricating a thermal convection channel on the first package on the back of the chip, including: S21. Using 3D printing technology to coat a molding material to form a wide channel structure, wherein the molding material is a material that can withstand the molding process temperature and can be dissolved by the chemical solution; S22. Deposit a thermal insulation layer on the surface of the cured wide channel structure, wherein the thermal insulation layer is a non-metallic low thermal conductivity material; S23. A second package is formed on the heat insulation layer using a molding process, and the surface of the second package is ground until the molding material in the wide channel structure is exposed. S24. The molding material is removed by dissolving it with a solution, forming a heat convection channel in the second package, which is connected to the back of the chip for heat conduction.

[0007] An advanced heat dissipation packaging structure prepared by the above method includes: chip; The package, composed of a first package and a second package, covers the surface of the chip; The heat convection channel is located inside the package and its bottom is in close contact with the back of the chip. The insulation layer, which is attached to the inner wall of the heat convection channel, is made of non-metallic low thermal conductivity material; The heat convection channel includes an inlet channel and an outlet channel, which are interconnected, and the width of the outlet channel is greater than that of the inlet channel.

[0008] As a further improvement of the present invention, the molding material includes any one of glass glue, ceramic slurry or high-temperature resistant resin.

[0009] As a further improvement of the present invention, the material of the heat insulation layer is SiO2 or silicon nitride (Si3N4).

[0010] As a further improvement of the present invention, the channel shape of the wide channel structure is freely customized based on the chip thermal distribution simulation results, and a dense channel layout is designed in the chip thermal density area.

[0011] As a further improvement of the present invention, the inlet and outlet channels of the heat convection channel adopt a Tesla valve channel structure.

[0012] As a further improvement of the present invention, the channel height of the outlet channel is higher than that of the inlet channel to optimize airflow conduction efficiency.

[0013] As a further improvement of the present invention, the inlet channel of the thermal convection channel is horizontally distributed and the outlet channel is vertically distributed, forming a three-dimensional airflow path.

[0014] The above technical solution has the following beneficial effects: 1. High-efficiency heat dissipation performance: The heat convection channel is based on the principle of natural air convection. Combined with the heat insulation layer, it concentrates heat in the channel area. Tests show that the chip operating temperature can be reduced by 15°C and the heat dissipation efficiency can be improved by 30%, effectively ensuring the stable operation of the chip under high load.

[0015] 2. Compact structure and thinness: The package integrates a heat dissipation channel, eliminating the need for an external heat sink. The overall structure thickness is reduced by more than 50%, making it particularly suitable for space-constrained scenarios (such as wearable devices and mobile devices), thus expanding the application boundaries of high-power chips.

[0016] 3. Low stress and high reliability: The use of a non-metallic thermal insulation layer and flexible channel design avoids the stress concentration problem caused by thick metal layers, and the packaging stress does not increase significantly. It is especially suitable for thin, large-size chips (such as HPC chips), improving packaging life and reliability.

[0017] 4. Process flexibility and scalability: The manufacturing method is compatible with 3D printing and standard packaging processes. The channel shape can be freely customized according to the chip's thermal distribution (such as serpentine or ring layout). It supports optimized designs such as Tesla valves and is easy to adapt to different chip types and thermal management requirements. Attached Figure Description

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0019] The structures, proportions, sizes, etc. shown in this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0020] Figure 1 This is a schematic diagram of the process provided by the present invention.

[0021] Figure 2 A schematic diagram of the advanced heat dissipation packaging structure provided by the present invention.

[0022] Figure 3 This is a schematic diagram of the thermal convection channel preparation process provided by the present invention.

[0023] Figure 4 A top view of the heat convection channel within the second package provided by the present invention.

[0024] In the picture: 1. Chip; 2. First package; 3. Insulation layer; 4. Second package; 5. Heat convection channel; 51. Inlet channel; 52. Outlet channel; 6. Wide channel structure. Detailed Implementation

[0025] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0026] like Figure 1 As shown, a method for fabricating an advanced heat dissipation packaging structure that accelerates air convection is presented. This method aims to solve the technical problems of insufficient heat dissipation efficiency of existing chip packaging structures and their inability to adapt to the thermal management requirements of high-density integrated chips. By combining customized heat dissipation channel design with advanced packaging technology, efficient air convection heat dissipation is achieved, ensuring long-term stable operation of the chip.

[0027] The specific manufacturing steps are as follows: S1. First, complete the core packaging process of the chip, including conventional processes such as chip-to-substrate bonding and wire connection. Then, use a molding process to cover the chip 1 with a first package 2. The molding material can be epoxy resin molding compound or other commonly used packaging materials in this field. Subsequently, the surface of the first package 2 is ground until the back of the chip 1 is completely exposed, ensuring that the subsequent heat dissipation channel can form an effective heat conduction path with the back of the chip, laying the structural foundation for the subsequent channel forming process.

[0028] S2. A heat dissipation channel is fabricated on the first package 2 on the back of chip 1. This process is the core of achieving efficient heat dissipation. Figure 3 As shown, the specific steps include: S21, preferentially using 3D printing technology to coat a molding material to form a wide-channel structure 6. The molding material is preferably glass glue, but other resistant materials with certain structural strength and removable by subsequent processes, such as ceramic slurry and high-temperature resistant resin, can also be used. The channel shape can be freely customized based on the simulation results of the actual thermal distribution of the chip. For example, a denser channel layout can be designed in areas with high thermal density of the chip. The inlet and outlet ports adopt Tesla valves or structural designs based on a similar unidirectional conduction principle to ensure unidirectional airflow and low flow resistance. The channel height at the outlet of the wide-channel structure is set higher than the channel height at the inlet to further optimize the airflow conduction efficiency.

[0029] S22. A SiO2 layer is deposited on the surface of the cured wide channel structure as a heat insulation layer 3. This heat insulation layer 3 can effectively block the conduction of heat to non-heat dissipation areas and ensure the heat dissipation of the heat dissipation channel.

[0030] S23. A second encapsulation body 4 is formed by molding on the heat insulation layer. The molding material can be the same as or have the same performance as the first encapsulation body. After the second encapsulation body 4 is completely cured, its surface is ground until the forming material (glass glue) in the wide channel structure 6 is exposed and the exposed part corresponds to the outlet part of the wide channel structure.

[0031] S24. The exposed molding material is dissolved using a suitable solution. After the molding material is completely removed, a final heat convection channel 5 is formed in the second package 4. This channel forms an efficient heat conduction connection with the back of the chip, which can quickly dissipate the heat generated by the chip through air convection, significantly improving the heat dissipation performance of the chip package structure.

[0032] like Figure 2 As shown, an advanced heat dissipation packaging structure prepared by the above method can effectively improve the heat dissipation efficiency of the chip during operation and adapt to the thermal management requirements of high-density integrated chips. It mainly includes a package (a combination of a first package 2 and a second package 4) disposed on the surface of chip 1. This package is a composite packaging structure prepared stepwise by the above molding process. Commonly used packaging materials in the art, such as epoxy resin molding compound, can be used, or other packaging materials with suitable performance can be employed.

[0033] The aforementioned package contains a heat convection channel 5, combined with Figure 4 As shown, the heat convection channel 5 is formed by removing the 3D-printed glass adhesive (or ceramic slurry, high-temperature resistant resin, or other similar durable materials). A heat insulation layer 3 of SiO2 is bonded to the inner wall of the heat convection channel 5, and the bottom of the heat convection channel 5 is in close contact with the surface of the chip 1 to ensure efficient heat conduction. The inlet channel 51 of the heat convection channel 5 is horizontally distributed, and the outlet channel 52 is vertically distributed. The inlet and outlet channels are interconnected to form a complete airflow channel.

[0034] Both the inlet channel 51 and the outlet channel 52 adopt the Tesla valve channel structure design, or other equivalent channel structures based on the unidirectional conduction principle can be used to ensure unidirectional airflow and reduce resistance. The width of the outlet channel 52 is set to be greater than that of the inlet channel, which can further optimize the airflow discharge efficiency, accelerate air convection, and quickly dissipate the heat generated by the chip to ensure long-term stable operation of the chip.

[0035] Example 1: High-performance computing chip packaging Chip type: Large thin chip (thickness < 0.2 mm), used for high-performance computing.

[0036] Channel design: Based on the thermal simulation results, a thermal convection channel is designed on the chip surface with an inlet diameter of 0.5mm and an outlet diameter of 1.0mm. The total height of the channel matches the chip thickness.

[0037] Production steps: Step 1: After chip mounting and molding are completed, grind until the back of the chip is exposed.

[0038] Step 2 involves 3D printing to coat a high-temperature resistant glass adhesive (50 μm wide), followed by curing to deposit a 100 nm thick SiO2 heat insulation layer. The glass adhesive is then dissolved with an alkaline solution to form heat convection channels.

[0039] Tests on the high-performance computing chip package prepared above showed that the chip operating temperature decreased by 15°C, the heat dissipation efficiency increased by 30%, and the packaging stress did not increase significantly.

[0040] Example 2: Wearable device chip packaging Chip type: Small, low-power chip for smartwatches.

[0041] Channel design: Based on the thermal simulation results, a thermal convection channel was designed on the chip surface with a channel height of only 0.1mm to accommodate the thin and light structure.

[0042] Material substitution: The glass adhesive is replaced with a fan-out encapsulation layer, and SiO2 is replaced with silicon nitride (Si3N4) to further reduce thermal conductivity.

[0043] Tests on the wearable device chip package prepared above show that the package thickness is reduced by 50%, the heat dissipation capacity meets the requirements for continuous use, and overcomes the size problem of traditional heat sinks.

[0044] This invention achieves a highly efficient and compact heat dissipation solution by integrating internal heat convection channels, making it particularly suitable for high-end chips and space-constrained scenarios.

[0045] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0046] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for manufacturing an advanced heat dissipation packaging structure that accelerates air convection, characterized in that, Includes the following steps: S1. After completing the core packaging process of chip (1), the first package body (2) is covered on the outside of the chip using a molding process, and the surface of the first package body is ground until the back of the chip is completely exposed. S2. A heat convection channel (5) is fabricated on the first package on the back of the chip, including: S21. Using 3D printing technology to coat a molding material to form a wide channel structure (6), wherein the molding material is a material that can withstand the molding process temperature and can be dissolved by the medicine; S22. A heat insulation layer (3) is deposited on the surface of the cured wide channel structure, wherein the heat insulation layer is a non-metallic low thermal conductivity material; S23. A second package (4) is formed on the heat insulation layer by molding process, and the surface of the second package is ground until the molding material in the wide channel structure is exposed. S24. The molding material is removed by dissolving it with a solution to form a heat convection channel (5) in the second package, and the heat convection channel is connected to the back of the chip for heat conduction.

2. An advanced heat dissipation packaging structure prepared by the method of claim 1, characterized in that, include: Chip (1); The package is composed of a first package (2) and a second package (4) and covers the chip surface; A heat convection channel (5) is disposed within the package, with its bottom in close contact with the back of the chip. The heat insulation layer (3) is attached to the inner wall of the heat convection channel and is made of non-metallic low thermal conductivity material; The heat convection channel (5) includes an inlet channel (51) and an outlet channel (52), which are interconnected, and the width of the outlet channel is greater than that of the inlet channel.

3. The manufacturing method according to claim 1, characterized in that, The forming material includes any one of glass glue, ceramic slurry, or high-temperature resistant resin.

4. The manufacturing method according to claim 1, characterized in that, The material of the heat insulation layer (3) is SiO2 or silicon nitride (Si3N4).

5. The manufacturing method according to claim 1, characterized in that, The channel shape of the wide channel structure (6) is freely customized based on the chip thermal distribution simulation results, and a dense channel layout is designed in the chip thermal density area.

6. The advanced heat dissipation packaging structure according to claim 2, characterized in that, The inlet channel (51) and outlet channel (52) of the heat convection channel (5) adopt Tesla valve channel structure.

7. The advanced heat dissipation packaging structure according to claim 2, characterized in that, The outlet channel (52) has a higher channel height than the inlet channel (51) to optimize airflow conduction efficiency.

8. The advanced heat dissipation packaging structure according to claim 2, characterized in that, The inlet channel (51) of the heat convection channel (5) is horizontally distributed, and the outlet channel (52) is vertically distributed, forming a three-dimensional airflow path.

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