A circuit board having a multi-layer heat conducting structure

Abstract

The utility model discloses a kind of circuit board with multilayer heat conduction structure belong to circuit board technical field, including substrate, heat conduction layer insulating layer and heat conduction via, the substrate is equipped with circuit layer, the controller, pin and a plurality of electrical components are equipped on the circuit layer;The quantity of heat conduction layer is at least two layers, and the heat conduction layer and circuit layer are alternately laminated;The insulating layer is arranged between adjacent heat conduction layer;Perpendicularly through the substrate and heat conduction layer;The utility model is alternately laminated design by heat conduction layer and circuit layer, combine high thermal conductivity coefficient material and array heat conduction via, construct vertical staggered three-dimensional heat dissipation network;Ultra-thin ceramic filling insulating layer balances electrical isolation and low thermal resistance demand, wave-shaped groove and heat dissipation component strengthen surface heat dissipation efficiency, oxidation-resistant layer and temperature sensor then improve durability and intelligent control ability, finally realize efficient, reliable, strong adaptability heat management solution.

Description

Technical Field

[0001] This utility model belongs to the field of circuit board technology, specifically relating to a circuit board with a multi-layer thermally conductive structure. Background Technology

[0002] As electronic devices evolve towards higher integration and higher power density, the thermal management of circuit boards is becoming increasingly critical. Traditional single-layer heat dissipation structures, due to their single heat conduction path and limited lateral diffusion capacity, are prone to localized high temperatures, affecting the stability and lifespan of core components such as controllers and power devices. While existing technologies such as metal substrates or simple thermal vias can alleviate some heat dissipation pressure, they still suffer from problems such as high interlayer thermal resistance, insufficient longitudinal thermal conductivity, and insulating materials hindering heat transfer. Furthermore, conventional rigid substrates are difficult to adapt to the installation requirements of flexible electronic devices, and high-temperature oxidation accelerates the degradation of the thermally conductive layer's performance.

[0003] To address the aforementioned shortcomings, this technology proposes a multi-layer thermally conductive circuit board: by alternating layers of thermally conductive and circuit layers, combined with high thermal conductivity materials (≥200W / (m·K)) and arrayed thermally conductive vias, a crisscrossing three-dimensional heat dissipation network is constructed; an ultra-thin ceramic-filled insulating layer balances the requirements for electrical isolation and low thermal resistance, while wavy grooves and heat dissipation components enhance surface heat dissipation efficiency; a flexible polyimide substrate adapts to curved surface layouts, and an anti-oxidation layer and temperature sensor improve durability and intelligent control capabilities, ultimately achieving an efficient, reliable, and highly adaptable thermal management solution. Utility Model Content

[0004] The purpose of this invention is to provide a circuit board with a multi-layer thermally conductive structure to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a circuit board with a multi-layer thermally conductive structure, comprising a substrate, a thermally conductive insulating layer, and thermally conductive vias.

[0006] A substrate, wherein a circuit layer is provided on the substrate, and the circuit layer is provided with a controller, pins and several electrical components;

[0007] A thermally conductive layer, wherein there are at least two thermally conductive layers, and the thermally conductive layers and circuit layers are alternately stacked;

[0008] An insulating layer is disposed between adjacent thermally conductive layers;

[0009] Multiple thermally conductive vias penetrate vertically through the substrate and the thermally conductive layer, and the thermally conductive vias are filled with a thermally conductive medium and a thermally conductive pipe.

[0010] It should be noted in the solution that the thermally conductive layer is composed of graphene thermally conductive sheets or metal-based composite materials, and its thermal conductivity is greater than or equal to 200 W / (m·K).

[0011] It is worth noting that the insulating layer is made of a ceramic-filled polymer material with a thickness of 0.05-0.2 mm and a thermal conductivity of 1-5 W / (m·K).

[0012] Furthermore, it should be noted that the heat-conducting through holes are arranged in an array, with a hole diameter of 0.1-0.5 mm and a hole spacing of 2-5 times the hole diameter. The heat-conducting medium is copper paste or thermal grease, and a fixing tube is provided in the middle of the heat-conducting pipe.

[0013] In a preferred embodiment, the plurality of electrical components include a heat dissipation component disposed on the surface of the outermost heat-conducting layer, the heat dissipation component including heat dissipation fins or a miniature cooling fan.

[0014] In a preferred embodiment, the surface of the heat-conducting layer is provided with a wavy groove (301), the groove depth is 0.1-0.3mm, and the spacing between adjacent grooves is 0.5-2mm.

[0015] In a preferred embodiment, a temperature sensor is also included, which is embedded in the edge of the substrate and connected to the thermally conductive layer via a wire.

[0016] In a preferred embodiment, the surface of the thermally conductive layer is provided with an anti-oxidation layer, which is a silicon nitride coating or an anodized aluminum layer with a thickness of 5-20 μm.

[0017] In a preferred embodiment, the substrate is a flexible substrate made of polyimide material with a thickness of 0.1-0.5 mm.

[0018] Compared with the prior art, the circuit board with a multi-layer thermally conductive structure provided by this utility model has at least the following beneficial effects:

[0019] (1) High-efficiency heat dissipation and balanced heat distribution: Through the synergistic effect of multiple alternating thermal conductive layers and arrayed thermally conductive vias, a three-dimensional thermal conductive network is formed. Combined with high thermal conductivity materials (≥200W / (m·K)), the heat transfer efficiency is significantly improved. The thermally conductive medium and heat pipes filled in the thermally conductive vias can quickly dissipate heat from inside the substrate. The corrugated grooves increase the heat dissipation surface area, effectively avoiding local overheating, ensuring the working stability of the controller and electrical components in the circuit layer, and extending their service life.

[0020] Compact and lightweight design: The insulation layer uses an ultra-thin ceramic-filled polymer (0.05-0.2mm), which achieves low thermal resistance while ensuring electrical isolation, avoiding the heat dissipation obstruction caused by traditional thick insulation layers. The polyimide material of the flexible substrate (0.1-0.5mm thickness) further reduces the overall weight, adapting to the installation requirements of wearable devices or curved electronic products and expanding application scenarios.

[0021] (2) Dynamic heat dissipation and intelligent control: Temperature sensors monitor the temperature changes of the substrate edge and thermal conductive layer in real time, and the outermost heat dissipation components (such as micro fans or fins) are linked to dynamically adjust the heat dissipation intensity to achieve on-demand heat dissipation and energy consumption optimization. An anti-oxidation layer (such as a silicon nitride coating) protects the surface of the thermal conductive layer, avoids material degradation at high temperatures, and ensures long-term heat dissipation performance stability.

[0022] Improved process adaptability and reliability: The aperture (0.1-0.5mm) and spacing (2-5 times the aperture) of the thermally conductive vias balance processing accuracy and heat dissipation efficiency. Fixed tubes enhance the structural strength of the vias, preventing the filling medium from failing due to thermal expansion and contraction. The composite structure of the flexible substrate and rigid thermally conductive layer can withstand mechanical deformation and thermal stress shocks, making it suitable for environments with high vibration or temperature fluctuations. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the exploded structure of this utility model;

[0024] Figure 2 For the present utility model Figure 1 An enlarged structural diagram at point A;

[0025] Figure 3 This is a schematic diagram of the substrate structure of this utility model.

[0026] In the diagram: 1. Substrate; 2. Circuit layer; 201. Controller; 202. Pin; 3. Thermal conductive layer; 301. Groove; 4. Insulating layer; 5. Thermal conductive via; 501. Thermal conductive medium; 502. Heat pipe; 5021. Fixing pipe; 6. Heat dissipation component; 7. Temperature sensor. Detailed Implementation

[0027] The present invention will be further described below with reference to the embodiments.

[0028] Please see Figure 1-3 This utility model provides a circuit board with a multi-layer thermally conductive structure, comprising: a substrate 1, a thermally conductive layer 3, an insulating layer 4, and thermally conductive vias 5, characterized in that:

[0029] The substrate 1 has a circuit layer 2 on it, and the circuit layer 2 has a controller 201, pins 202 and several electrical components.

[0030] The thermal conductive layer 3 has at least two layers, and the thermal conductive layer 3 and the circuit layer 2 are stacked alternately.

[0031] Insulating layer 4 is disposed between adjacent heat-conducting layers 3;

[0032] Multiple thermally conductive through holes 5 vertically penetrate the substrate 1 and the thermally conductive layer 3. The thermally conductive through holes 5 are filled with a thermally conductive medium 501 and a thermally conductive pipe 502.

[0033] Further as Figure 1 As shown, it is worth noting that the thermal conductive layer 3 is composed of graphene thermal conductive sheets or metal-based composite materials with a thermal conductivity greater than or equal to 200 W / (m·K). By using graphene or metal-based composite materials with high thermal conductivity (≥200 W / (m·K)) as the thermal conductive layer 3, the lateral heat conduction efficiency is significantly improved, the heat generated by the circuit layer 2 is quickly absorbed and diffused, and the local temperature is avoided from being too high. At the same time, the material is lightweight and the structure is strong.

[0034] Further as Figure 1 As shown, it is worth noting that the insulating layer 4 is made of ceramic-filled polymer material with a thickness of 0.05-0.2 mm and a thermal conductivity of 1-5 W / (m·K). The ceramic-filled polymer insulating layer 4 achieves the dual functions of electrical isolation and low thermal resistance (1-5 W / (m·K)) with an ultra-thin thickness (0.05-0.2 mm), which not only prevents short circuits but also reduces heat accumulation between layers and optimizes the overall heat dissipation path.

[0035] Further as Figure 1 and Figure 2 As shown, it is worth noting that the heat-conducting through holes 5 are arranged in an array, with a hole diameter of 0.1-0.5mm and a hole spacing of 2-5 times the hole diameter. The heat-conducting medium 501 is copper paste or thermal grease, and the heat-conducting pipe 502 has a fixing pipe 5021 in the middle. The array of heat-conducting through holes 5 (hole diameter 0.1-0.5mm, spacing 2-5 times the hole diameter) improves the longitudinal heat conduction efficiency through dense distribution. The copper paste / thermal grease 501 filling and the design of the fixing pipe 5021 enhance the stability of the through hole structure, ensure the reliability of the heat conduction channel under thermal expansion and contraction, and avoid the medium falling off or deforming.

[0036] This solution employs the following working process: The circuit board achieves efficient thermal management through a multi-layered thermally conductive structure and a three-dimensional heat dissipation path. The heat generated by the controller 201 and electrical components in circuit layer 2 is first laterally absorbed and diffused by the adjacent high thermal conductivity (≥200W / (m·K)) thermally conductive layer 3 (such as graphene or metal-based composite material). Its surface wavy grooves 301 enhance convection by increasing the heat dissipation area. The multi-layered thermally conductive layers 3 and circuit layer 2 are alternately stacked, and heat is longitudinally guided through the array of thermally conductive vias 5 that vertically penetrate the substrate 1. These vias are filled with copper paste / silicone grease 501 and heat pipes 502 with fixing tubes 5021, forming a low thermal resistance channel that rapidly transfers internal heat to the surface. The heat dissipation fins or micro-fans 6 of the outermost thermally conductive layer 3 accelerate heat dissipation, while temperature sensors 7 monitor and provide real-time temperature data, dynamically adjusting the heat dissipation intensity in conjunction with the controller 201. The ceramic-filled polymer insulating layer 4 reduces interlayer thermal resistance while isolating the circuit. The flexible polyimide substrate 1 adapts to curved surface mounting requirements. The anti-oxidation layer (silicon nitride / anodic aluminum oxide) ensures the long-term stability of the thermal conductive layer. Ultimately, it achieves the coordinated regulation of heat "lateral diffusion-vertical conduction-surface heat dissipation" to ensure the thermal reliability of high-density circuits.

[0037] Based on the above working process, it can be seen that: by using graphene or metal-based composite materials with high thermal conductivity (≥200W / (m·K)) as the thermal conductive layer 3, the lateral heat conduction efficiency is significantly improved, the heat generated by the circuit layer 2 is quickly absorbed and diffused, and the local temperature is avoided from being too high. At the same time, the material is lightweight and the structure is strong. The ceramic-filled polymer insulating layer 4 achieves the dual functions of electrical isolation and low thermal resistance (1-5W / (m·K)) with an ultra-thin thickness (0.05-0.2mm). It not only prevents circuit short circuits, but also reduces heat accumulation between layers and optimizes the overall heat dissipation path. The array-type thermal conductive holes 5 (hole diameter 0.1-0.5mm, spacing 2-5 times the hole diameter) improve the longitudinal thermal conductivity through dense distribution. The copper paste / silicone grease 501 filling and the design of the fixing tube 5021 enhance the stability of the hole structure, ensure the reliability of the heat conduction channel under thermal expansion and contraction, and avoid the medium falling off or deforming.

[0038] Further as Figure 1 As shown, it is worth noting that several electrical components include heat dissipation components 6 disposed on the surface of the outermost heat-conducting layer 3. The heat dissipation components 6 include heat dissipation fins or miniature cooling fans. The heat dissipation fins or miniature fans 6 of the outermost heat-conducting layer 3 provide passive / active heat dissipation capabilities, accelerate surface heat dissipation for high-power scenarios, improve overall heat dissipation efficiency, and adapt to different workload requirements.

[0039] Further as Figure 2As shown, it is worth noting that the surface of the heat-conducting layer 3 is provided with a wavy groove 301 with a groove depth of 0.1-0.3mm and a spacing of 0.5-2mm between adjacent grooves. The wavy groove 301 enhances air convection heat dissipation by increasing the surface area of ​​the heat-conducting layer 3 (depth 0.1-0.3mm, spacing 0.5-2mm), which is especially suitable for environments without forced air cooling and further improves the natural heat dissipation effect.

[0040] Further as Figure 1 As shown, it is worth noting that the system also includes a temperature sensor 7, which is embedded in the edge of the substrate 1 and connected to the heat-conducting layer 3 via wires. The temperature sensor 7 monitors the temperature of the edge of the substrate 1 in real time and feeds it back to the controller 201 to achieve intelligent temperature control linkage, dynamically adjust the working state of the heat dissipation component 6, balance heat dissipation performance and energy consumption, and improve the system's energy efficiency and reliability.

[0041] Further as Figure 1 As shown, it is worth noting that the surface of the thermal conductive layer 3 is provided with an anti-oxidation layer, which is a silicon nitride coating or an anodized aluminum layer with a thickness of 5-20μm. The silicon nitride or anodized aluminum anti-oxidation layer (5-20μm) protects the surface of the thermal conductive layer 3, prevents the thermal conductivity from decaying due to high-temperature oxidation, extends the service life of the circuit board, and ensures long-term stable operation.

[0042] Further as Figure 1 As shown, it is worth noting that substrate 1 is a flexible substrate made of polyimide material with a thickness of 0.1-0.5mm. The flexible polyimide substrate 1 (thickness 0.1-0.5mm) gives the circuit board bendable characteristics, adapting to the installation requirements of curved electronic devices or wearable products. At the same time, the multi-layer thermal conductive structure compensates for the impact of flexible deformation on the heat dissipation path, expanding the application scenarios.

[0043] In summary: The heat dissipation component 6 includes heat dissipation fins or a miniature cooling fan. The heat dissipation fins or miniature fan 6 of the outermost heat-conducting layer 3 provide passive / active heat dissipation capabilities, accelerating surface heat dissipation in high-power scenarios, improving overall heat dissipation efficiency, and adapting to different workload requirements. The wavy grooves 301 enhance air convection heat dissipation by increasing the surface area of ​​the heat-conducting layer 3 (depth 0.1-0.3mm, spacing 0.5-2mm), which is especially suitable for environments without forced air cooling, further improving the natural heat dissipation effect. The silicon nitride or anodized aluminum anti-oxidation layer (5-20μm) protects the surface of the heat-conducting layer 3. To prevent thermal conductivity degradation caused by high-temperature oxidation, extend the lifespan of the circuit board, and ensure long-term stable operation, the flexible polyimide substrate 1 (0.1-0.5mm thick) gives the circuit board bendable characteristics, adapting to the installation requirements of curved electronic devices or wearable products. At the same time, the multi-layer thermal conductive structure compensates for the impact of flexible deformation on the heat dissipation path, expanding application scenarios. The temperature sensor 7 monitors the edge temperature of the substrate 1 in real time and feeds it back to the controller 201 to achieve intelligent temperature control linkage, dynamically adjust the working state of the heat dissipation component 6, balance heat dissipation performance and energy consumption, and improve system energy efficiency and reliability.

[0044] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A circuit board with a multilayer thermally conductive structure, comprising a substrate (1), a thermally conductive layer (3), an insulating layer (4), and thermally conductive vias (5), characterized in that: A substrate (1) is provided with a circuit layer (2), and the circuit layer (2) is provided with a controller (201), pins (202) and several electrical components; The thermal conductive layer (3) has at least two layers, and the thermal conductive layer (3) and the circuit layer (2) are stacked alternately. An insulating layer (4) is disposed between adjacent thermally conductive layers (3); Multiple thermally conductive through holes (5) penetrate vertically through the substrate (1) and the thermally conductive layer (3), and the thermally conductive through holes (5) are filled with a thermally conductive medium (501) and a thermally conductive pipe (502).

2. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The thermally conductive layer (3) is composed of graphene thermally conductive sheets or metal-based composite materials, and its thermal conductivity is greater than or equal to 200 W / (m·K).

3. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The insulating layer (4) is made of ceramic-filled polymer material with a thickness of 0.05-0.2 mm and a thermal conductivity of 1-5 W / (m·K).

4. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The heat-conducting through holes (5) are arranged in an array, with a hole diameter of 0.1-0.5 mm and a hole spacing of 2-5 times the hole diameter. The heat-conducting medium (501) is copper paste or thermal grease, and a fixing tube (5021) is provided in the middle of the heat-conducting pipe (502).

5. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The plurality of electrical components include a heat dissipation component (6) disposed on the surface of the outermost heat-conducting layer (3), the heat dissipation component (6) including heat dissipation fins or a miniature cooling fan.

6. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The surface of the heat-conducting layer (3) is provided with a wavy groove (301), the groove depth is 0.1-0.3mm, and the spacing between adjacent grooves is 0.5-2mm.

7. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: It also includes a temperature sensor (7), which is embedded in the edge of the substrate (1) and connected to the heat-conducting layer (3) by a wire.

8. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The surface of the thermally conductive layer (3) is provided with an anti-oxidation layer, which is a silicon nitride coating or an anodized aluminum layer with a thickness of 5-20 μm.

9. A circuit board with a multi-layer thermally conductive structure according to claim 1, characterized in that: The substrate (1) is a flexible substrate made of polyimide material with a thickness of 0.1-0.5 mm.

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