A diamond-based, high power density thermal management package substrate

Abstract

This invention discloses a high-power-density thermal management packaging substrate based on a diamond substrate, comprising a substrate layer and multiple copper foil layers. The substrate layer has a front side and a back side. Multiple copper foil layers are arranged at intervals and cover the front side of the substrate layer, and multiple metal layers are deposited on the surface of the copper foil layers. The technical solution of this invention aims to improve heat dissipation efficiency.

Description

Technical Field

[0001] This utility model relates to the field of packaging substrate technology, and in particular to a high-power-density thermal management packaging substrate based on diamond. Background Technology

[0002] Currently, high-power LEDs primarily use alumina or aluminum nitride ceramics as heat dissipation substrates. While these materials possess good insulation and mechanical strength, their thermal conductivity is limited, making it difficult to meet the ever-increasing power density requirements. Traditional substrate structures suffer from the following significant drawbacks: a single planar heat dissipation path leads to high thermal resistance, causing a sharp rise in chip junction temperature during high-power operation; mismatch in the thermal expansion coefficients between the copper foil and the substrate easily leads to interface delamination; uneven current distribution causes localized overheating and efficiency degradation; and insufficient double-sided heat dissipation capacity limits further power increases. These problems severely restrict the development of brightness, lifespan, and reliability in high-power LEDs, necessitating the development of new, highly efficient heat dissipation substrate solutions. Utility Model Content

[0003] The main objective of this invention is to provide a high-power-density thermal management packaging substrate based on a diamond base, which aims to improve heat dissipation efficiency.

[0004] To achieve the above objectives, this utility model proposes a diamond-based high-power-density thermal management packaging substrate, comprising:

[0005] A substrate layer having a front side and a back side;

[0006] Multiple copper foil layers are arranged at intervals and cover the front side of the substrate layer, and multiple metal layers are deposited on the surface of the copper foil layers.

[0007] In one possible implementation, the substrate layer is made of diamond.

[0008] In one possible implementation, the copper foil layer has uniformly spaced notches on one or both sides, with the notches of adjacent copper foil layers corresponding to each other and dividing the surface of the copper foil layer into multiple conductive areas.

[0009] In one possible implementation, each of the conductive regions is deposited with two metal layers.

[0010] In one possible implementation, multiple conductive vias are provided on both sides of the substrate layer and on the copper foil layer corresponding to that position.

[0011] In one possible implementation, a metal layer is also deposited on a portion of the back surface of the substrate layer.

[0012] This invention utilizes a diamond substrate layer with its ultra-high thermal conductivity as the core heat dissipation carrier. Combined with spaced copper foil layers on the front side and selectively deposited metal layers on the back side, a three-dimensional, highly efficient heat conduction path is constructed. The unique copper foil notch design and partitioned metallization layout optimize current distribution, while the edge conductive vias enable interconnection of the front and back circuits and double-sided heat dissipation. This structure allows the substrate to maintain excellent insulation while significantly reducing thermal resistance and controlling the LED junction temperature at a lower level, significantly improving device lifespan and luminous efficiency stability. It is particularly suitable for applications with stringent heat dissipation requirements, such as high-power-density LEDs and laser diodes. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0014] Figure 1 This is a front structural schematic diagram of an embodiment of the diamond-based high-power-density thermal management packaging substrate of this utility model;

[0015] Figure 2 This is a schematic diagram of the back structure of an embodiment of the diamond-based high-power-density thermal management packaging substrate of this utility model;

[0016] Figure 3 This is an exploded view of an embodiment of the diamond-based high-power-density thermal management packaging substrate of this utility model.

[0017] Explanation of icon numbers:

[0018] 1. Substrate layer; 11. Front side; 12. Back side; 2. Copper foil layer; 21. Notch; 22. Conductive area; 3. Metal layer; 4. Conductive via.

[0019] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0021] Reference Figures 1 to 3This utility model proposes a high-power density thermal management packaging substrate based on diamond, including a substrate layer 1 and multiple copper foil layers 2. The substrate layer 1 has a front side 11 and a back side 12. Multiple copper foil layers 2 are arranged at intervals and cover the front side 11 of the substrate layer 1. Multiple metal layers 3 are deposited on the surface of the copper foil layers 2.

[0022] Understandably, substrate layer 1 uses a highly thermally conductive material as its core, with both the front side 11 and the back side 12 used for heat dissipation. Multiple copper foils are spaced apart on the front side 11 of the substrate for conductivity and auxiliary heat dissipation, avoiding thermal stress concentration. A metal layer 3 is plated on the surface of the copper foils to enhance conductivity, oxidation resistance, and improve bonding strength. In this example, the metal layer 3 is deposited on the surface of the copper foils using an immersion gold process. The type of metal is selected according to actual needs, such as immersion nickel-gold, immersion tin, immersion silver, etc. Immersion gold layers have excellent conductivity. As a thin layer with excellent conductivity, it can reduce resistance and loss in signal transmission, thereby improving the overall circuit performance. In this example, only nickel and gold are present on the copper foil layer 2. These two metals do not affect the transmission quality when transmitting signals in the copper layer, which is crucial for ensuring the normal operation and performance stability of the LED.

[0023] Substrate layer 1 rapidly conducts heat laterally, while copper foil enhances localized heat dissipation, reducing LED junction temperature and extending lifespan. Simultaneously, the discrete copper foil layout minimizes the risk of deformation due to material expansion mismatch. Metal layer 3 ensures low-resistance connections and improves current carrying capacity, making it suitable for high-power LEDs. This design maintains high thermal conductivity while balancing reliability and electrical performance, meeting the heat dissipation requirements of high-power LEDs.

[0024] Reference Figures 1 to 3 In one embodiment of this utility model, the substrate layer 1 is made of diamond.

[0025] Understandably, the core function of diamond substrates is as follows: diamond's thermal conductivity far exceeds that of conventional metals such as copper and aluminum, which can quickly diffuse the heat generated by LED chips laterally and avoid local overheating; at the same time, it has a low coefficient of thermal expansion, which is more compatible with semiconductor materials, reduces thermal stress, and improves device reliability; and diamond itself is non-conductive, which can serve as an ideal insulating heat dissipation substrate to avoid the risk of leakage.

[0026] Reference Figures 1 to 3 In one embodiment of the present invention, notches 21 are uniformly provided on one or both sides of the copper foil layer 2, and the notches 21 of adjacent copper foil layers 2 correspond to each other and divide the surface of the copper foil layer 2 into multiple conductive areas 22.

[0027] Understandably, evenly distributed notches 21 are made on both sides of the copper foil layer 2 (the two outermost copper foil layers 2 are on one side), dividing the copper foil surface into multiple independent conductive areas 22. The notches 21 of different copper foil layers 2 are aligned with each other, forming regular heat and electricity conduction channels, avoiding excessive concentration of heat or current.

[0028] The notch 21 divides the copper foil into multiple conductive areas, allowing the current to flow more evenly through the LED chip and avoiding local overload; it also reduces the "current crowding effect" and improves the luminous efficiency and lifespan of the LED; the notch 21 forms a heat flow channel, which, combined with the high thermal conductivity of the diamond substrate, accelerates the lateral diffusion of heat; it can also prevent the copper foil from deforming or delaminating due to uneven thermal expansion.

[0029] Reference Figures 1 to 3 In one embodiment of this utility model, each conductive region 22 has two metal layers 3 deposited.

[0030] Understandably, on the surface of each independent conductive region 22 divided by the notch 21, two metal layers 3 are uniformly deposited, corresponding to the P / N pins of the LED chip respectively, forming a directional current path. The double metal layers 3 constitute a complete current loop, eliminating the current bias phenomenon of traditional surface electrodes. This layout allows the horizontal LEDs to be connected in series and the vertical LEDs to be connected in parallel. The specific number of series and parallel connections can be adjusted according to actual needs and is not further limited here.

[0031] Reference Figures 1 to 3 In one embodiment of this utility model, multiple conductive vias 4 are provided on both sides of the substrate layer 1 and the copper foil layer 2 corresponding to the position.

[0032] Understandably, arrayed vias are formed on both sides of the diamond substrate and on the corresponding copper foil layer 2. The vias vertically penetrate both sides of the substrate, and the inner walls are plated with conductive metal layers 3. The vias are electrically interconnected with the metal layers 3 on the upper and lower surfaces. Their key function is that the vias act as vertical conductive channels, enabling interconnection between the front and back circuits, allowing bidirectional current flow, improving current carrying capacity, and making them suitable for LED arrays requiring high current drive, thus solving the heat dissipation bottleneck in the edge areas of high-power devices.

[0033] Reference Figures 2 to 3 In one embodiment of the present invention, a metal layer 3 is also deposited on a portion of the back surface 12 of the substrate layer 1.

[0034] Understandably, a metal layer 3 is also deposited in a specific area on the back side 12 of the diamond substrate, distributed in strips or blocks, corresponding to the position of the copper foil layer 2 on the front side 11. Its core function is to cooperate with the edge conductive vias 4 to realize the interconnection of the circuits on the front and back sides, and can serve as a ground layer or part of the power loop; the metal layer 3 serves as a heat diffusion layer, which quickly conducts the heat of the diamond substrate to the external heat sink, especially for high heat-generating areas such as directly below the LED chip to enhance heat dissipation.

[0035] This invention utilizes a diamond substrate layer 1, with its ultra-high thermal conductivity, as the core heat dissipation carrier. Combined with copper foil layers 2 spaced apart on the front side 11 and selectively deposited metal layers 3 on the back side 12, a three-dimensional, highly efficient heat conduction path is constructed. The unique copper foil notch design 21 and partitioned metallization layout optimize current distribution, while the edge conductive vias 4 enable interconnection of the front and back circuits and double-sided heat dissipation. This structure allows the substrate to maintain excellent insulation while significantly reducing thermal resistance and controlling the LED junction temperature at a lower level, significantly improving device lifespan and luminous efficiency stability. It is particularly suitable for applications with stringent heat dissipation requirements, such as high-power-density LEDs and laser diodes.

[0036] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0037] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A high-power-density thermal management packaging substrate based on a diamond substrate, characterized in that, include: A substrate layer having a front side and a back side; Multiple copper foil layers are arranged at intervals and cover the front side of the substrate layer, and multiple metal layers are deposited on the surface of the copper foil layers.

2. The diamond-based high-power-density thermal management packaging substrate according to claim 1, characterized in that, The substrate layer is made of diamond.

3. The diamond-based high-power-density thermal management packaging substrate according to claim 2, characterized in that, The copper foil layer has evenly spaced notches on one or both sides, and the notches of adjacent copper foil layers correspond to each other, dividing the surface of the copper foil layer into multiple conductive areas.

4. The diamond-based high-power-density thermal management packaging substrate according to claim 3, characterized in that, Each of the aforementioned conductive regions has two metal layers deposited on it.

5. The diamond-based high-power-density thermal management packaging substrate according to claim 1, characterized in that, Multiple conductive vias are provided on both sides of the substrate layer and on the copper foil layers corresponding to both sides of the substrate layer.

6. The diamond-based high-power-density thermal management packaging substrate according to claim 1, characterized in that, A metal layer is also deposited on a portion of the back surface of the substrate layer.

Images