A multi-layer laminated high thermal conductivity metal substrate

Abstract

The utility model relates to electronic packaging technical field especially, it relates to a multilayer superimposed high thermal conductivity metal substrate, including aluminium material base layer, the upper surface of aluminium material base layer is provided with the first fiber reinforced composite layer through the mode of hot pressing, the upper surface of first fiber reinforced composite layer is coated with first high thermal conductivity insulating layer, the surface of first high thermal conductivity insulating layer is provided with intermediate thin copper layer through the mode of hot pressing. By introducing fiber reinforced composite layer in first and second high thermal conductivity insulating layer respectively, the tensile strength, elastic modulus and bending stiffness of insulating layer are improved significantly, the structure effectively inhibits the creep behavior of polymer matrix under high temperature, reduces the internal stress caused by the mismatch of thermal expansion coefficient, prevents interlaminar delamination, warping or cracking, and improves the structural reliability of the substrate under temperature cycling and mechanical vibration environment.

Description

Technical Field

[0001] This utility model relates to the field of electronic packaging technology, and in particular to a multilayer laminated high thermal conductivity metal substrate. Background Technology

[0002] With the rapid development of electronic information technology, high power density electronic devices are widely used in industries, communications, lighting and transportation. These devices generate a lot of heat during operation. If the heat cannot be dissipated in a timely and effective manner, the chip junction temperature will rise, leading to performance degradation, decreased reliability and even device failure. Therefore, high-performance electronic packaging places higher demands on heat dissipation substrates, which must have excellent thermal conductivity, good electrical insulation, high mechanical strength and excellent thermal stability.

[0003] Currently, high thermal conductivity metal substrates are typically composed of an aluminum base layer, a high thermal conductivity insulating layer, and a copper circuit layer laminated together. However, there is a significant difference in the coefficient of thermal expansion between the aluminum and the high thermal conductivity insulating layer. Under frequent temperature cycling or high-temperature operating conditions, thermal stress is easily generated at the interface, leading to delamination, cracking, or solder joint fatigue, which seriously affects the long-term reliability of the device. Furthermore, polymer-based insulating layers are prone to creep at high temperatures, and have low tensile strength and modulus, resulting in insufficient overall rigidity of the substrate. During assembly or use, warping and deformation are likely to occur, affecting subsequent mounting accuracy and electrical connection stability.

[0004] Therefore, there is an urgent need to provide a multilayer laminated high thermal conductivity metal substrate that can ensure overall thermal conductivity while enhancing mechanical strength and thermal stability. Utility Model Content

[0005] To overcome the shortcomings of traditional metal-based copper clad laminate insulation layers, such as high interfacial stress due to thermal expansion mismatch, low mechanical strength, and easy creep and delamination at high temperatures, this invention provides a multilayer laminated high thermal conductivity metal substrate that can ensure overall thermal conductivity while enhancing mechanical strength and thermal stability.

[0006] To address the aforementioned issues, this utility model employs the following technical solution: a multilayer laminated high thermal conductivity metal substrate, comprising an aluminum substrate, a first fiber-reinforced composite layer disposed on the upper surface of the aluminum substrate by hot pressing, a first high thermal conductivity insulating layer coated on the upper surface of the first fiber-reinforced composite layer, an intermediate thin copper layer disposed on the surface of the first high thermal conductivity insulating layer by hot pressing, a second fiber-reinforced composite layer disposed on the upper surface of the intermediate thin copper layer by hot pressing, a second high thermal conductivity insulating layer coated on the upper surface of the second fiber-reinforced composite layer, and a circuit layer disposed on the surface of the second high thermal conductivity insulating layer.

[0007] Preferably, both the first fiber-reinforced composite layer and the second fiber-reinforced composite layer are made of glass fiber fabric-reinforced modified epoxy resin composite material.

[0008] Preferably, the aluminum substrate has multiple through-holes for heat dissipation.

[0009] Preferably, a thermally conductive pad is attached to the lower surface of the aluminum substrate.

[0010] Preferably, thermally conductive silicone grease is used to fill the space between the aluminum substrate and the thermal pad.

[0011] Preferably, the sides of the aluminum substrate are coated with a corrosion-resistant edge-sealing coating.

[0012] Compared with the prior art, the present invention has the following technical effects: 1. By introducing fiber-reinforced composite layers into the first and second high thermal conductivity insulation layers respectively, the tensile strength, elastic modulus and bending stiffness of the insulation layer are significantly improved. This structure effectively suppresses the creep behavior of the polymer matrix at high temperature, reduces the internal stress caused by the mismatch of thermal expansion coefficients, prevents interlayer delamination, warping or cracking, and improves the structural reliability of the substrate under temperature cycling and mechanical vibration environments.

[0013] 2. By attaching thermal pads to the lower surface of the aluminum substrate and filling the interface with thermal grease, a high-efficiency composite thermal interface structure is formed, creating a more efficient heat conduction channel, significantly reducing the contact thermal resistance between the substrate and the mounting interface, and improving the overall heat dissipation efficiency. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0015] Figure 2 This is an exploded view of the aluminum base material, the first high thermal conductivity insulation layer, and the second high thermal conductivity insulation layer of this utility model.

[0016] Figure 3 This is an exploded view of the aluminum base material, the first fiber-reinforced composite layer, and the second fiber-reinforced composite layer components of this utility model.

[0017] Figure 4 This is an exploded view of the aluminum base material and thermal pads and other components of this utility model.

[0018] The markings in the diagram are as follows: 1-Aluminum base layer, 2-First high thermal conductivity insulation layer, 3-Intermediate thin copper layer, 4-Second high thermal conductivity insulation layer, 5-Circuit layer, 6-Heat dissipation hole, 7-First fiber reinforced composite layer, 8-Second fiber reinforced composite layer, 9-Thermal pad, 10-Thermal grease, 11-Corrosion resistant edge sealing coating. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] Example 1: Please refer to Figures 1-3 A multilayer laminated high thermal conductivity metal substrate includes an aluminum base layer 1. A first fiber-reinforced composite layer 7 is formed on the upper surface of the aluminum base layer 1 by hot pressing. A first high thermal conductivity insulating layer 2 is coated on the upper surface of the first fiber-reinforced composite layer 7. An intermediate thin copper layer 3 is formed on the surface of the first high thermal conductivity insulating layer 2 by hot pressing. A second fiber-reinforced composite layer 8 is formed on the upper surface of the intermediate thin copper layer 3 by hot pressing. Both the first fiber-reinforced composite layer 7 and the second fiber-reinforced composite layer 8 are made of glass fiber fabric-reinforced modified epoxy resin composite material to enhance interlayer bonding. To suppress polymer creep and thermal expansion mismatch at high temperatures and improve the substrate's resistance to thermal shock, a second high thermal conductivity insulating layer 4 is coated on the upper surface of the second fiber-reinforced composite layer 8. A circuit layer 5 is disposed on the surface of the second high thermal conductivity insulating layer 4. Nine through-hole heat dissipation holes 6 are opened on the aluminum substrate 1 to increase the contact area between the aluminum substrate and the external air and enhance natural convection heat dissipation. A corrosion-resistant edge sealing coating 11 is coated on the side of the aluminum substrate 1 to isolate the side of the aluminum substrate 1 from the external environment, effectively blocking the intrusion path of moisture and corrosive media, and significantly improving the long-term reliability of the substrate in harsh environments.

[0021] When the multilayer laminated high thermal conductivity metal substrate is in use, heat is generated from the circuit layer 5 and then rapidly conducted to the aluminum base layer 1 via the second high thermal conductivity insulating layer 4, the second fiber-reinforced composite layer 8, the intermediate thin copper layer 3, the first high thermal conductivity insulating layer 2, and the first fiber-reinforced composite layer 7. The heat is then dissipated to the environment through its large bottom surface and side heat dissipation holes 6. The intermediate thin copper layer 3 significantly improves the lateral heat diffusion capability and avoids the accumulation of local hot spots. The double fiber-reinforced composite layer not only improves the tensile strength and modulus of the insulating layer, but also effectively suppresses the thermal expansion of the polymer at high temperatures and the creep behavior during long-term service, significantly enhancing the dimensional stability and anti-delamination capability of the substrate under temperature cycling conditions.

[0022] Example 2: Based on Example 1, please refer to... Figure 4A thermally conductive pad 9 is attached to the lower surface of the aluminum substrate 1 to further improve the overall heat dissipation efficiency. Thermally conductive silicone grease 10 is filled between the aluminum substrate 1 and the thermally conductive pad 9 to fill the gap between the aluminum substrate 1 and the thermally conductive pad 9 and achieve good heat transfer.

[0023] Before attaching the thermal pad 9, a layer of thermal grease 10 is evenly coated on the bottom surface of the aluminum substrate 1, and then the thermal pad 9 is pressed onto it to form a composite thermal interface structure, which builds a more efficient heat conduction channel, significantly reduces the contact thermal resistance between the substrate and the mounting interface, and improves the overall heat dissipation efficiency.

[0024] Although this disclosure has been described with respect to only a limited number of embodiments, those skilled in the art who benefit from this disclosure will understand that various other embodiments can be devised without departing from the scope of this invention. Therefore, the scope of this invention should be limited only by the appended claims.

Claims

1. A multilayer laminated high thermal conductivity metal substrate, comprising an aluminum base layer (1), characterized in that: The upper surface of the aluminum substrate (1) is provided with a first fiber reinforced composite layer (7) by hot pressing. The upper surface of the first fiber reinforced composite layer (7) is coated with a first high thermal conductivity insulating layer (2). The surface of the first high thermal conductivity insulating layer (2) is provided with an intermediate thin copper layer (3) by hot pressing. The upper surface of the intermediate thin copper layer (3) is provided with a second fiber reinforced composite layer (8) by hot pressing. The upper surface of the second fiber reinforced composite layer (8) is coated with a second high thermal conductivity insulating layer (4). The surface of the second high thermal conductivity insulating layer (4) is provided with a circuit layer (5).

2. A multilayer laminated high thermal conductivity metal substrate according to claim 1, characterized in that: Both the first fiber-reinforced composite layer (7) and the second fiber-reinforced composite layer (8) are made of glass fiber fabric-reinforced modified epoxy resin composite material.

3. A multilayer laminated high thermal conductivity metal substrate according to claim 2, characterized in that: The aluminum substrate (1) has multiple through-holes (6) for heat dissipation.

4. A multilayer laminated high thermal conductivity metal substrate according to claim 3, characterized in that: A thermally conductive pad (9) is attached to the lower surface of the aluminum substrate (1).

5. A multilayer laminated high thermal conductivity metal substrate according to claim 4, characterized in that: Thermal grease (10) is filled between the aluminum substrate (1) and the thermal pad (9).

6. A multilayer laminated high thermal conductivity metal substrate according to claim 5, characterized in that: The sides of the aluminum substrate (1) are coated with a corrosion-resistant edge sealing coating (11).

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