Metal heat dissipation substrate, LED module and lighting equipment

Abstract

The invention discloses a metal heat dissipation substrate, an LED module and lighting equipment, and relates to the technical field of LED packaging. The structure specifically comprises a heat-conducting metal layer, an insulating layer and a conducting layer, the heat-conducting metal layer is divided into a first polarity region and a second polarity region; the insulating layer only covers the first polarity area of the heat-conducting metal layer, and the conductive layer is arranged on the insulating layer and forms a first polarity conductive path which is electrically isolated from the metal layer; the second polarity area of the heat conduction metal layer is in an exposed state, a second polarity bonding pad can be directly formed, and the heat conduction metal layer is configured to be a conductive and heat dissipation path of the second polarity bonding pad. The insulating layer ink is arranged on the heat-conducting metal layer, so that the problems of inaccurate aging temperature caused by large thermal resistance of a traditional substrate and light attenuation test data distortion caused by high-temperature color change of the ink are solved, and the LED substrate has the advantages of high heat dissipation efficiency, good optical stability and reliable electrical connection.

Description

Technical Field

[0001] This invention relates to the field of LED packaging technology, and in particular to a metal heat sink substrate, an LED module, and a lighting device. Background Technology

[0002] In the LED industry chain, to evaluate the reliability and lifespan of LED chips, surface-mount LED chips are typically mounted on a heat-dissipating substrate for prolonged high-temperature aging and photoelectric performance testing. Currently, the industry widely uses metal-based copper-clad laminates, commonly known as aluminum-based laminates.

[0003] In existing technologies, a typical aluminum substrate usually consists of a three-layer composite structure: an uppermost layer of copper foil, a middle layer of insulation, and a bottom layer of aluminum plate. The copper foil is used to solder the pads for the positive and negative electrodes of the LED chips; the insulation layer mainly serves to electrically isolate the upper charged copper foil from the bottom aluminum plate; and the aluminum plate mainly serves to provide support and assist in heat dissipation. In addition, the entire surface of the circuit layer, except for the solder pads, is usually coated with a layer of solder resist ink to increase the reflectivity of the board surface or prevent stray light interference.

[0004] However, using the existing aluminum substrates for aging tests still has some shortcomings. Specifically: Because the thermal conductivity of the insulating layer is much lower than that of metal materials, the overall thermal resistance of the aluminum plate is relatively high. When the LED is working, the chip is mainly located in the negative electrode pad area, causing a large amount of heat to be generated at the negative electrode pad. This heat must first penetrate the insulating layer before it can be conducted to the bottom aluminum plate for dissipation, making it easy for the heat generated by the chip to accumulate at the bottom of the LED, thus making it difficult to improve the overall thermal conductivity. This causes the aging environment temperature to deviate from the set value, making it impossible to realistically and stably simulate the preset aging conditions. In addition, during long-term high-temperature aging, the white ink tends to yellow, and the black ink tends to fade. Since LED light decay testing is extremely sensitive to the optical reflection characteristics of the background environment, physical changes in the ink color will cause changes in the reflectivity of the substrate surface, making the calculated light decay results inaccurate and affecting the judgment of the LED's reliability.

[0005] Therefore, this application aims to solve the problems of high thermal resistance of traditional insulating layers, resulting in low thermal conductivity of aluminum substrates; and the problem of ink aging and discoloration at high temperatures, leading to deviations in test data and inaccurate light decay results. Summary of the Invention

[0006] The main objective of this invention is to provide a metal heat dissipation substrate, an LED module, and a lighting device, which aims to solve the problems of high thermal resistance of traditional insulation layers, low thermal conductivity of aluminum substrates, and inaccurate light decay results caused by ink aging and discoloration due to high temperatures leading to test data deviations.

[0007] To achieve the above objectives, the present invention provides a metal heat dissipation substrate, comprising a thermally conductive metal layer and an insulating layer and a conductive layer disposed on a portion of the surface of the thermally conductive metal layer; the thermally conductive metal layer has a first polarity region and a second polarity region; The insulating layer covers the first polar region of the thermally conductive metal layer, the conductive layer covers the insulating layer, and a first polar conductive path is formed on the conductive layer. The first polar conductive path is electrically isolated from the thermally conductive metal layer. The second polar region of the thermally conductive metal layer is exposed to form a second polarity pad, and the thermally conductive metal layer is configured as a conductive path for the second polarity pad.

[0008] Furthermore, it also includes an isolation layer disposed on the thermally conductive metal layer and located at the junction of the first polarity region and the second polarity region. The isolation layer is used to prevent the first polarity conductive path from short-circuiting with the thermally conductive metal layer.

[0009] Furthermore, the isolation layer covers the sidewall of the first polar conductive path and the sidewall of the insulating layer, and one side of the isolation layer extends and adheres to a portion of the surface of the thermally conductive metal layer.

[0010] Furthermore, the thermally conductive metal layer is an aluminum layer or an aluminum alloy layer, and the conductive layer is a copper foil layer.

[0011] Furthermore, it also includes an ink layer that covers a portion of the surface of the conductive layer, with another portion of the conductive layer exposed to form a first polarity pad.

[0012] Furthermore, the ink layer is distributed over a portion of the area covered by the insulating layer.

[0013] Furthermore, the first polar region is configured as a positive electrode region, and the first polar conductive path is a positive electrode conductive path; the second polar region is configured as a negative electrode region, the second polar pad is a negative electrode pad, and the thermally conductive metal layer is a conductive path of the negative electrode pad.

[0014] Furthermore, the insulating layer is a thermally conductive insulating medium layer, and the insulating layer is fixed to the first polar region of the thermally conductive metal layer by lamination or printing.

[0015] This application also discloses an LED module, including an LED light-emitting element and the aforementioned metal heat dissipation substrate; the LED light-emitting element has a first polarity pin and a second polarity pin, the first polarity pin is soldered to a first polarity conductive path, and the second polarity pin is soldered to a second polarity pad of the thermally conductive metal layer.

[0016] This application also discloses a lighting device, including a housing and an LED module installed in the housing.

[0017] The above technical solution has the following advantages: This application sets the second polarity region of the thermally conductive metal layer to an exposed state, and directly forms the second polarity pad on the thermally conductive metal layer. This eliminates the insulating layer and copper foil layer located below the heat dissipation pad in the traditional structure. As a result, the heat generated by the LED chip does not need to penetrate the low thermal conductivity insulating layer and is directly conducted to the high thermal conductivity thermally conductive metal layer. This greatly reduces the thermal resistance in the vertical direction and effectively solves the core defects of the prior art, such as excessively high chip junction temperature and inaccurate aging temperature simulation caused by the thermal resistance of the insulating layer.

[0018] By distributing the ink layer in the first polar region covered by the insulating layer, while leaving the second polar region uncovered, the yellowing, discoloration, or fading of traditional organic inks during long-term high-temperature aging is avoided, thus ensuring a constant background reflectivity.

[0019] By setting an isolation layer at the junction of the first polarity region and the second polarity region, and making it cover the sidewall of the conductive path and extend to the surface of the heat-conducting metal layer, the isolation layer increases the creepage distance between the positive and negative electrodes of the LED, blocks the flow path of molten solder from the high-potential copper layer to the low-potential aluminum layer during reflow soldering, thereby effectively preventing short circuits between the positive and negative electrodes and improving the product yield and safety. Attached Figure Description

[0020] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings, wherein: Figure 1 This is a schematic diagram of the planar structure of the present invention; Figure 2 This is a cross-sectional structural diagram of the present invention.

[0021] In the diagram: 100, first polarity region; 200, conductive layer; 300, insulating layer; 400, first polarity pad; 401, first positive pad; 402, second positive pad; 500, LED chip; 600, isolation layer; 700, second polarity region; 800, thermally conductive metal layer; 900, second polarity pad; 901, first negative pad; 902, second negative pad. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the invention and do not constitute a limitation thereof.

[0023] The core purpose of this application is to solve two major problems existing in the aluminum substrate for LED aging test: first, the low thermal conductivity of the 300 insulating layer leads to high thermal resistance, resulting in inaccurate aging temperature; second, the ink turns yellow or white at high temperatures, causing deviations in the light decay test data.

[0024] This application relates to a metal heat sink substrate, an LED module, and a lighting device. For ease of understanding, the basic concepts involved in this application are first defined: Thermally conductive metal layer 800: refers to the bottom support material of the metal heat dissipation substrate, usually made of aluminum, copper or their alloys. It serves both as a structural support and as the main heat dissipation function, and is preferably made of aluminum or aluminum alloy.

[0025] Exposed state: In this application, the insulating layer 300 and the conductive layer 200 are removed above the second polarity region 700 of the thermally conductive metal layer 800, so that the thermally conductive metal layer 800 is directly exposed to the air or directly used as a welding surface.

[0026] Conductive layer 200: refers to the electrical contact part of the metal heat sink substrate, which is usually made of copper material, and is preferably formed by etching the circuit board.

[0027] like Figure 1 and Figure 2 As shown, this embodiment provides a metal heat dissipation substrate, mainly used in LED aging tests or high-power lighting scenarios with high requirements for light decay testing accuracy and large heat dissipation needs. It includes a thermally conductive metal layer 800 and an insulating layer 300 and a conductive layer 200 disposed on a portion of the surface of the thermally conductive metal layer 800. The thermally conductive metal layer 800 has a first polarity region 100 and a second polarity region 700. The insulating layer 300 covers the first polarity region 100 of the thermally conductive metal layer 800, and the conductive layer 200 covers the insulating layer 300. The conductive layer 200 forms a first polarity conductive path, which is electrically isolated from the thermally conductive metal layer 800. The second polarity region 700 of the thermally conductive metal layer 800 is exposed to form a second polarity pad 900, and the thermally conductive metal layer 800 is configured as the conductive path of the second polarity pad 900.

[0028] like Figure 1 and Figure 2 As shown, this embodiment provides a metal heat dissipation substrate with an asymmetrical layered structure in the thickness direction. Specifically, the overall framework of the metal heat dissipation substrate is a thermally conductive metal layer 800, which is a continuous metal plate that serves not only as the supporting framework of the metal heat dissipation substrate but also as the main carrier for heat conduction. In planar layout, the thermally conductive metal layer 800 is divided into a first polar region 100 and a second polar region 700.

[0029] Specifically, such as Figure 2It can be seen that the first polar region 100 is as follows Figure 2 In the left half, the metal heat dissipation substrate maintains the traditional three-layer structure: metal, insulation, and heat dissipation. The insulating layer 300 is applied to the surface of the first polarity region 100 of the thermally conductive metal layer 800 using a high-temperature pressing or coating process. The conductive layer 200, made of copper, is attached to the top surface of the insulating layer 300. Through etching or machining, the conductive layer 200 forms a first polarity conductive path. This first polarity conductive path is used to transmit current signals of a first polarity, such as the positive or negative signal of a power supply. Due to the presence of the insulating layer 300, the current transmitted by the conductive layer 200 cannot flow directly to the bottom thermally conductive metal layer 800, thus achieving electrical isolation between the first polarity conductive path and the thermally conductive metal layer 800.

[0030] Specifically, such as Figure 2 It can be seen that the second polar region 700 is as follows Figure 2 In the right half, the second polarity region 700 differs from existing technologies in that the insulating layer 300 and conductive layer 200 are pre-removed. Therefore, the surface of the thermally conductive metal layer 800 is exposed, meaning it is directly exposed without the insulating layer 300 and conductive layer 200 covering it. A second polarity pad 900 is provided on the exposed surface of the thermally conductive metal layer 800. This allows the thermally conductive metal layer 800 to be reused as part of the circuit, configured as a conductive path for the second polarity pad 900, allowing current to be directly transmitted through it. In the second polarity region 700 of the thermally conductive metal layer 800, the vertical thermal resistance depends on the thermal conductivity of the metal material itself, eliminating the thermal resistance bottleneck caused by the extremely low thermal conductivity of the insulating layer 300 in conventional structures.

[0031] This application also includes an isolation layer 600, which is disposed on the thermally conductive metal layer 800 and located at the junction of the first polarity region 100 and the second polarity region 700. The isolation layer 600 is used to prevent the first polarity conductive path from short-circuiting with the thermally conductive metal layer 800.

[0032] like Figure 2As shown, since the first polar region 100 of the thermally conductive metal layer 800 has an insulating layer 300 and a conductive layer 200, while the second polar region 700 of the thermally conductive metal layer 800 is exposed, there is a height difference between the two, which is equal to the thickness of the insulating layer 300 and the conductive layer 200, forming a stepped structure at their interface. During the reflow soldering process, the molten solder paste easily flows from the higher conductive layer 200 to the lower surface of the thermally conductive metal layer 800 under the action of surface tension and gravity. If the first polar conductive path is directly connected to the thermally conductive metal layer 800, it will lead to a serious power short circuit. Therefore, this embodiment introduces an isolation layer 600. The isolation layer 600 is disposed at the interface between the first polar region 100 and the second polar region 700, and the isolation layer 600 is made of a material with high insulation resistivity and high temperature resistance, such as photosensitive solder resist ink, thermosetting epoxy resin, or special insulating adhesive. The isolation layer 600 is used to block the flow path of solder, thereby effectively preventing a short circuit between the first polar conductive path and the thermally conductive metal layer 800, ensuring the electrical safety of the metal heat dissipation substrate.

[0033] The isolation layer 600 covers the sidewall of the first polar conductive path and the sidewall of the insulating layer 300, and one side of the isolation layer 600 extends and adheres to a portion of the surface of the thermally conductive metal layer 800.

[0034] like Figure 2 As can be seen, this embodiment defines the covering shape of the isolation layer 600. Specifically, the isolation layer 600 covers the sidewall of the conductive layer 200 facing the second polarity region 700, and also covers the sidewall of the underlying insulating layer 300. In addition, the bottom of the isolation layer 600 extends to the exposed area of ​​the thermally conductive metal layer 800 and adheres to a portion of the surface of the thermally conductive metal layer 800.

[0035] In this embodiment, the extension width of the isolation layer 600 on the surface of the thermally conductive metal layer 800 is designed to be 0.3 mm to 0.6 mm, thereby increasing the surface creepage distance between the conductive layer 200 and the thermally conductive metal layer 800. Through the extended coverage of the isolation layer 600, electron migration or arc discharge can be prevented even in high-humidity environments. Simultaneously, the top of the isolation layer 600 is higher than the surface of the conductive layer 200, making the coverage height of the isolation layer 600 slightly higher than the surface of the conductive layer 200. The isolation layer 600 can block flowing solder paste, utilizing the surface tension principle of liquids to confine the solder within the first polar region 100 of the conductive layer 200, further eliminating the risk of short circuits between the conductive layer 200 and the thermally conductive metal layer 800.

[0036] The thermally conductive metal layer 800 is an aluminum layer or an aluminum alloy layer, and the conductive layer 200 is a copper foil layer.

[0037] In this preferred embodiment, the thermally conductive metal layer 800 is made of aluminum or an aluminum alloy. Specifically, it is preferably made of 5052 or 6061 series aluminum alloy sheet with a thickness of 1.0 mm to 2.0 mm. Aluminum alloy has the combined advantages of low cost and high thermal conductivity, making it suitable as a substrate for mass production aging tests. The conductive layer 200 is made of copper foil, preferably electrolytic copper foil. Copper has excellent conductivity, can carry large currents, and its surface is easy to plate with nickel-gold or tin, making it suitable as a circuit transmission medium.

[0038] This application also includes an ink layer that covers a portion of the surface of the conductive layer 200 and exposes another portion of the surface of the conductive layer 200 to form a first polarity pad 400.

[0039] like Figure 1 As shown, in this embodiment, an ink layer is also provided on the surface of the conductive layer 200. The ink layer is typically a white or black solder resist ink. The ink layer mainly covers the surface of the conductive layer 200 in the first polarity region 100, serving to prevent oxidation, provide insulation, and resist soldering. To achieve electrical connection, windows are provided on the ink layer, exposing a portion of the surface of the conductive layer 200. The exposed copper foil forms the first polarity pad 400. Figure 1 and Figure 2 As shown, the first polarity pad 400 includes a first positive pad 401 located at the edge of the conductive layer 200 and a second positive pad 402 located at the other edge of the conductive layer 200 for connecting components, ensuring the long-term reliability of the copper circuit; the use of an ink layer not only provides protection and insulation for the main parts of the conductive layer 200, but also facilitates wiring on both sides of the conductive layer 200. Figure 1 As can be seen, the two oblong holes on the far left are the first positive pad 401, used to connect to the positive terminal of the external power supply, and the second positive pad 402 is... Figure 1 The first positive electrode pad 401 and the second positive electrode pad 402 are connected through the first polarity conductive path of the conductive layer 200 at the middle position, and the second positive electrode pad 402 serves as the positive input terminal of the lamp bead 500.

[0040] like Figure 1 As shown, the ink layer is distributed in a portion of the area covered by the insulating layer 300.

[0041] In this embodiment, the ink layer is only distributed in a portion of the coverage area of ​​the insulating layer 300, namely the first polar region 100. No ink layer is applied to the exposed second polar region 700 of the thermally conductive metal layer 800. Since this application assumes the second polar region 700 is the negative electrode region, which connects to the chip of the LED bead 500, the second polar region 700 generates a large amount of heat and has high thermal resistance. To avoid the existing white or black ink from yellowing or fading after prolonged high-temperature aging, leading to data drift and misjudgment of the light decay performance of the LED bead 500, this embodiment utilizes the fact that the thermally conductive metal layer 800 is extremely stable in its physical and chemical properties at high temperatures and will not discolor by leaving the second polar region 700 unpainted. Therefore, keeping the large negative electrode region requiring heat dissipation exposed can significantly improve the accuracy and consistency of aging test data. In this embodiment, the thermally conductive metal layer 800 is preferably aluminum or an aluminum alloy, which generates aluminum oxide in air, and its chemical properties are extremely stable.

[0042] The first polarity region 100 is configured as a positive polarity region, and the first polarity conductive path is a positive polarity conductive path; the second polarity region 700 is configured as a negative polarity region, the second polarity pad 900 is a negative polarity pad, and the thermally conductive metal layer 800 is a conductive path for the negative polarity pad.

[0043] like Figure 2 As shown, in this embodiment, the first polar region 100 is defined as the positive electrode region, and the conductive layer 200 on the insulating layer 300 is etched into a positive electrode conductive path. Figure 1 The first positive electrode pad 401 and the second positive electrode pad 402 have been described in the above embodiments. The second positive electrode pad 402 is used to connect the positive electrode of the LED bead 500. The second polarity region 700 is defined as the negative electrode region. Correspondingly, the exposed surface of the thermally conductive metal layer 800 forms a second polarity pad 900. The second polarity pad 900 includes a first negative electrode pad 901 and a second negative electrode pad 902. The first negative electrode pad 901 is used to connect the negative electrode of the LED bead 500, and the second negative electrode pad 902 is used to connect the negative electrode of the power supply. The thermally conductive metal layer 800 is a negative grounding path. In existing products, the positive and negative electrode pads of the power LED chip are both set on the conductive layer 200. This makes it difficult for the heat generated by the original copper layer to be dissipated through the separated aluminum layer, causing heat to accumulate at the conductive layer 200. The accumulated heat also accelerates the aging of the ink layer. In this embodiment, the second polar region 700 of the thermally conductive metal layer 800 is defined as the negative electrode region, and the negative electrode region is in an exposed state. It can directly use the thermally conductive metal layer 800 for heat dissipation without passing through the insulating layer 300, thereby achieving the technical effect of generating heat and dissipating heat at the negative electrode.

[0044] The current flow direction in this application can be determined through... Figure 2As shown by the arrow, the power supply is connected to the first positive pad 401, so that the current passes through the first positive pad 401, the conductive layer 200, the second positive pad 402, the LED 500, the first negative pad 901, the thermally conductive metal layer 800, and the second negative pad 902 in sequence. The second negative pad 902 is used to connect to the negative terminal of the power supply.

[0045] like Figure 2 As shown, the insulating layer 300 is a thermally conductive insulating medium layer, and the insulating layer 300 is fixed to the first polar region 100 of the thermally conductive metal layer 800 by pressing or printing.

[0046] In this embodiment, the insulating layer 300 is selected as a thermally conductive insulating dielectric layer, preferably a modified epoxy resin doped with micron-sized thermally conductive ceramic powder, such as alumina (Al2O3) or boron nitride (BN), whose thermal conductivity is typically between 1.0-3.0 W / m·K, much higher than that of ordinary FR-4 (0.3 W / m·K). In terms of manufacturing process, the insulating layer 300 can be fixed in the following two ways: Lamination process: The prepreg and copper foil are cut into specific shapes to cover only the positive electrode area, and then laminated with the whole aluminum plate at high temperature and vacuum.

[0047] Printing process: A screen printing process is used to selectively print liquid insulating ink onto the first polarity region 100 of the thermally conductive metal layer 800, which then cures to form a dielectric layer. This ensures insulation where needed, while eliminating thermal resistance where heat dissipation is required.

[0048] This application also discloses an LED module, including an LED light-emitting element and the aforementioned metal heat sink substrate; the LED light-emitting element has a first polarity pin and a second polarity pin, the first polarity pin is soldered to a first polarity conductive path, and the second polarity pin is soldered to a second polarity pad 900 of a thermally conductive metal layer 800.

[0049] like Figure 2 As shown, this embodiment also provides an LED module, which includes the above-mentioned metal heat sink substrate and LED light-emitting element. The LED light-emitting element is the lamp bead 500 in the figure. The LED light-emitting element is connected between the second positive electrode pad 402 and the first negative electrode pad 901.

[0050] The first polarity pin and the second polarity pin of the LED light-emitting element are selected as positive and negative, respectively. The first polarity pin of the LED light-emitting element is soldered to the second positive electrode pad 402 above the conductive layer 200 with solder paste, and its second polarity pin is directly soldered to the first negative electrode pad 901 on the surface of the thermally conductive metal layer 800 with solder paste.

[0051] Through the above circuit connection method, the heat generated by the chip in the LED light-emitting element flows sequentially from the negative electrode pin, the first negative electrode pad 901, the thermally conductive metal layer 800 and the external environment, thereby avoiding the heat insulation effect of the existing insulating layer 300. This ensures that there is no low thermal conductivity material blocking the entire heat dissipation path, and its actual theoretical thermal resistance is close to the material limit.

[0052] In existing solutions, the thermal conductivity of the aluminum substrate is at most 2 W / mK. With the improvement of this application, the thermal conductivity of the metal heat dissipation substrate of this application is increased to 150~200 W / mK, making the aging temperature of the LED 500 more stable and accurate. At the same time, the ink layer on the surface only needs to be applied to a part of the positive electrode conductive layer 200, which greatly reduces the impact of ink discoloration.

[0053] This application also discloses a lighting device, including a housing and an LED module installed in the housing.

[0054] This embodiment also covers a terminal lighting device that includes the aforementioned LED module. The lighting device includes a housing (not shown) and an LED module installed within the housing. The lighting device can be a street light, industrial lamp, floodlight, or an aging test bench specifically designed for LED reliability testing. When used as a fixture for an aging test bench, because the metal heat sink substrate employs an exposed negative electrode area without ink coverage, the aging test bench can provide better temperature control accuracy and higher optical testing stability.

[0055] Based on the above embodiment, a further improvement is made: the thermally conductive metal layer 800 is made of aluminum, and the exposed aluminum layer serves as the solder pad. To ensure the reliability of soldering, this embodiment adds necessary surface treatment processes. Since the surface of the aluminum layer is extremely prone to oxidation, making it impossible to apply solder, a chemical nickel-gold or silver plating process is performed on the exposed aluminum surface of the second polarity solder pad 900 to ensure that the solder paste can effectively wet the aluminum substrate.

[0056] To further address the issue of cold solder joints that easily occur during the soldering of large-area metal heat dissipation substrates, this embodiment introduces a microtexture structure on the exposed metal surface of the second polarity pad 900. Specifically, in the pad area of ​​the thermally conductive metal layer 800, a grid-like microgroove or micropit with a depth of 10μm to 30μm is fabricated using laser engraving or chemical micro-etching processes. This microstructure increases the contact surface area between the solder and the metal substrate, enhances the mechanical bonding strength of the solder joints through capillary forces, and allows bubbles generated by flux evaporation during reflow soldering to escape through these microgrooves.

[0057] To provide full disclosure, this embodiment further explains that the exposed area of ​​the thermally conductive metal layer 800 can be formed in various ways, such as milling or lamination. This application uses lamination as an example. Before lamination, the insulating layer 300 is pre-punched or cut so that it retains only the shape of the first polarity region 100. Then, the copper foil, the insulating layer 300, and the aluminum layer are stacked and pressed together. This method has high material utilization and does not damage the surface of the aluminum layer.

[0058] In summary, this application removes the insulating layer 300, the conductive layer 200, and the ink layer in the second polar region 700 of the thermally conductive metal layer 800, and uses the thermally conductive metal layer 800 directly as the first negative electrode pad 901 and the second negative electrode pad 902, breaking the thermal resistance limit of existing aluminum substrates and solving the heat dissipation problem and light decay test problem of existing aluminum substrates.

[0059] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A metal heat dissipation substrate, characterized in that, It includes a thermally conductive metal layer and an insulating layer and a conductive layer disposed on a portion of the surface of the thermally conductive metal layer; the thermally conductive metal layer has a first polarity region and a second polarity region; The insulating layer covers the first polar region of the thermally conductive metal layer, the conductive layer covers the insulating layer, the conductive layer forms a first polar conductive path, and the first polar conductive path is electrically isolated from the thermally conductive metal layer. The second polar region of the thermally conductive metal layer is exposed to form a second polarity pad, and the thermally conductive metal layer is configured as a conductive path for the second polarity pad.

2. The metal heat dissipation substrate as described in claim 1, characterized in that, It also includes an isolation layer disposed on the thermally conductive metal layer and located at the junction of the first polarity region and the second polarity region. The isolation layer is used to prevent the first polarity conductive path from short-circuiting with the thermally conductive metal layer.

3. The metal heat dissipation substrate as described in claim 2, characterized in that, The isolation layer covers the sidewall of the first polar conductive path and the sidewall of the insulating layer, and one side of the isolation layer extends and adheres to a portion of the surface of the thermally conductive metal layer.

4. The metal heat dissipation substrate as described in claim 1, characterized in that, The thermally conductive metal layer is an aluminum layer or an aluminum alloy layer, and the conductive layer is a copper foil layer.

5. The metal heat dissipation substrate as described in claim 1, characterized in that, It also includes an ink layer that covers a portion of the surface of the conductive layer and exposes another portion of the surface of the conductive layer to form a first polarity pad.

6. The metal heat dissipation substrate as described in claim 5, characterized in that, The ink layer is distributed in a portion of the area covered by the insulating layer.

7. The metal heat dissipation substrate as described in any one of claims 1 to 6, characterized in that, The first polar region is configured as a positive polar region, and the first polar conductive path is a positive conductive path; the second polar region is configured as a negative polar region, the second polar pad is a negative polar pad, and the thermally conductive metal layer is a conductive path of the negative polar pad.

8. The metal heat dissipation substrate as described in claim 1, characterized in that, The insulating layer is a thermally conductive insulating medium layer, and the insulating layer is fixed to the first polar region of the thermally conductive metal layer by pressing or printing.

9. An LED module, characterized in that, The invention includes an LED light-emitting element and a metal heat-dissipating substrate as described in any one of claims 1 to 8; the LED light-emitting element has a first polarity pin and a second polarity pin, the first polarity pin being soldered to a first polarity conductive path, and the second polarity pin being soldered to a second polarity pad of the thermally conductive metal layer.

10. A lighting device, characterized in that, It includes a housing and an LED module as described in claim 9, which is installed within the housing.

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