Micro-channel heat dissipation structure
By creating gaps in the diamond layer and forming microchannels in the substrate, a silicon-diamond composite structure was developed, which solved the problem of integrating diamond into high-power electronic devices and achieved efficient heat dissipation and protection of device performance.
Patent Information
- Application Number
- CN202422382968.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-09-29
AI Technical Summary
In existing technologies, diamond is difficult to integrate into high-power electronic devices, resulting in its heat dissipation effect not being fully utilized, and the microchannel structure is prone to damage to the device during processing.
A silicon-diamond combined microchannel heat dissipation structure is designed. By creating gaps in the diamond layer and forming microchannels in the substrate layer using an etching material, the device layer is protected from damage, while the high thermal conductivity of the diamond layer is used to improve the heat dissipation effect.
A microchannel heat dissipation structure with high thermal conductivity was achieved, which improved the temperature uniformity of electronic devices, facilitated the integration of high-frequency and high-power devices, and protected the electrical performance of the device layer.
Smart Images
Figure CN223513955U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of heat dissipation technology for microelectronic devices, specifically a microchannel heat dissipation structure. Background Technology
[0002] With the development of miniaturization and integration technologies in electronic devices, device sizes are shrinking while power is increasing dramatically. This has led to thermal failures and instability in electronic devices, severely hindering their further development. Microchannels, as a highly efficient thermal management solution, have attracted widespread attention. The main research objectives are to further reduce pressure drop, enhance heat transfer, and improve overall temperature uniformity through optimization. Diamond possesses excellent properties such as high hardness, stable chemical properties, high thermal conductivity, and a high damage threshold, making it a promising candidate for device thermal management applications. However, the difficulty in processing diamond and integrating it into high-power devices severely hinders its heat dissipation performance. With the continuous development of diamond growth technology, inch-scale large-area diamonds are now available, providing material support for the application of diamond in device thermal management. Therefore, developing high thermal conductivity structures on diamond is essential. Utility Model Content
[0003] Therefore, it is necessary to provide a silicon-diamond combined microchannel heat dissipation structure to improve the thermal management efficiency of high-power electronic devices.
[0004] To achieve the above objectives, this utility model provides a technical solution:
[0005] A microchannel heat dissipation structure, the microchannel heat dissipation structure comprising:
[0006] Substrate layer;
[0007] A diamond layer is grown on one side of the substrate layer. A first slit is formed through the diamond layer along its thickness direction. The first slit is used to allow etching material to enter the substrate layer.
[0008] Microchannels are disposed within the substrate layer and are obtained by isotropic etching of the substrate layer.
[0009] A device layer, which is grown on the other side of the substrate layer.
[0010] Optionally, the depth of the first gap is equal to the thickness of the diamond layer, and the depth of the second gap is less than the thickness of the substrate layer.
[0011] Optionally, there are multiple first gaps, and these multiple first gaps are spaced apart in the diamond layer.
[0012] Optionally, the substrate layer has a second slit along its thickness direction, the first slit and the second slit overlap and are connected, and the etching material enters the substrate layer sequentially through the first slit and the second slit.
[0013] Optionally, there are multiple second gaps, and the number of the first gaps and the number of the second gaps are the same, with the multiple second gaps spaced apart on the substrate layer.
[0014] Optionally, the widths of the first slit and the second slit range from 1µm to 100µm.
[0015] Optionally, the substrate material includes silicon, silicon carbide, or sapphire.
[0016] Optionally, the width of the microchannel is 10um-800um, and the spacing between two adjacent microchannels is 5um-5mm.
[0017] Optionally, the thickness of the substrate layer is 50um-5mm.
[0018] Optionally, the thickness of the diamond layer is 10um-10mm.
[0019] Optionally, the thickness of the device layer is 1µm-500µm.
[0020] The beneficial effects of this utility model are:
[0021] In this invention, the interface between the substrate layer, diamond layer, and device layer is formed through growth, exhibiting strong bonding energy, high stability, and low thermal resistance. Furthermore, a first slit is created in the diamond layer, allowing etching material to enter the substrate layer and isotropically etch microchannels. This protects the device layer from damage and ensures its quality, further protecting the electronic devices within the device layer from electrical performance degradation caused by the microchannel fabrication process. Additionally, the first slit in the diamond layer induces turbulence in the fluid within the substrate microchannels, improving heat dissipation. The high thermal conductivity of the diamond layer enhances the lateral thermal conductivity of the device, thereby improving temperature uniformity. The heat dissipation structure facilitates the integration of electronic devices, and the device layer can be used to fabricate various high-frequency, high-power devices as needed. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the fabrication process and structure of a microchannel heat dissipation structure in one embodiment.
[0023] Among them, 1. Substrate layer; 2. Diamond layer; 3. Device layer; 4. Microchannel; 5. First gap; 6. Second gap. Detailed Implementation
[0024] 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.
[0025] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0026] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the term "and / or" throughout the text includes three solutions; taking A and / or B as an example, it includes technical solution A, technical solution B, and a technical solution that simultaneously satisfies A and B. Furthermore, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.
[0027] refer to Figure 1 This application provides a microchannel heat dissipation structure, which includes: a substrate layer 1, a diamond layer 2, and a device layer 3. The diamond layer 2 is grown on one side of the substrate layer 1, and a first slit 5 is formed through the diamond layer 2 along its thickness direction. The first slit 5 is used to allow etching material to enter the substrate layer 1. A microchannel 4 is disposed in the substrate layer 1 and is obtained by isotropic etching of the substrate layer 1. The microchannel 4 is connected to the first slit 5. The device layer 3 is grown on the other side of the substrate layer 1, that is, the device layer 3 and the diamond layer 2 are disposed on opposite surfaces of the substrate layer 1.
[0028] In this invention, the interface between the substrate layer 1, diamond layer, and device layer 3 is formed through growth, exhibiting strong bonding energy, high stability, and low thermal resistance. Furthermore, a first slit 5 is formed in the diamond layer 2, allowing etching material to enter the substrate layer 1 through this slit, thereby isotropically etching the substrate layer 1 to obtain microchannels 4. This protects the device layer 3 from damage and ensures its quality, further guaranteeing that the electronic devices within the device layer 3 are not affected by electrical performance degradation caused during the fabrication of the microchannels 4. Additionally, the first slit 5 in the diamond layer 2 induces turbulence in the fluid within the microchannels 4 of the substrate layer 1, improving heat dissipation. The high thermal conductivity of the diamond layer 2 enhances the lateral thermal conductivity of the device, thereby improving the temperature uniformity of the electronic devices. This heat dissipation structure facilitates the integration of electronic devices, and the device layer 3 can be used to fabricate various high-frequency, high-power devices as needed.
[0029] Specifically, the cross-sectional shape of the microchannel 4 is rectangular, trapezoidal, elliptical, triangular, or irregular.
[0030] Furthermore, the substrate 1 material includes at least one of silicon, silicon carbide, and sapphire.
[0031] refer to Figure 1 There are multiple first gaps 5, which are spaced apart on the diamond layer 2. In this embodiment, the multiple first gaps 5 are evenly distributed on the diamond layer 2.
[0032] The substrate layer 1 has a second slit 6 along its thickness direction. The first slit 5 and the second slit 6 overlap and are connected. The etching material enters the substrate layer 1 through the first slit 5 and the second slit 6 in sequence.
[0033] Specifically, the first slit 5 and the second slit 6 are formed by cutting slits of a first depth and width on the surface of the diamond layer 2 using laser cutting technology, penetrating the diamond layer 2 and extending into the substrate layer 1 sequentially. In this embodiment, the first slit 5 and the second slit 6 are completely aligned and overlap to form a uniform slit. Furthermore, the width of the first slit 5 and the second slit 6 ranges from 1µm to 100µm.
[0034] In this example, the widths of the first gap 5 and the second gap 6 are equal. In other embodiments, the widths of the first gap 5 and the second gap 6 may not be equal.
[0035] Furthermore, the total depth of the first gap 5 and the second gap 6 is greater than the thickness of the diamond layer 2 and less than the total thickness of the diamond layer 2 and the substrate layer 1. More specifically, the depth of the first gap 5 is equal to the thickness of the diamond layer 2, and the depth of the second gap 6 is less than the thickness of the substrate layer 1. With this configuration, after the microchannel 4 is formed, the other side of the substrate layer 1 is a complete surface, which facilitates the growth of the device layer 3 and prevents interruptions caused by the second gap 6.
[0036] There are multiple second gaps 6, and the number of first gaps 5 and second gaps 6 is the same. The multiple second gaps 6 are spaced apart on the substrate layer 1. In this embodiment, the multiple second gaps 6 are uniformly disposed on the substrate layer 1.
[0037] Furthermore, the width of the microchannel 4 is 10um-800um, and there are multiple microchannels 4. The multiple microchannels 4 are evenly spaced within the substrate layer 1, and the spacing between two adjacent microchannels 4 is 5um-5mm.
[0038] Furthermore, the thickness of substrate 1 is 50um-5mm.
[0039] Furthermore, the thickness of the diamond layer 2 is 10um-10mm.
[0040] Furthermore, the thickness of device layer 3 is 1um-500um.
[0041] This invention also provides a method for preparing a microchannel heat dissipation structure, comprising the following steps:
[0042] Substrate 1 is polished on both sides, and diamond is grown on one side of substrate 1. Specifically, high-quality diamond with a thickness of 10um-5mm is grown using CVD technology. The material of substrate 1 is silicon, silicon carbide, or other substrate materials suitable for growing diamond and device layer 3.
[0043] A first slit 5 and a second slit 6 of a certain width (ranging from 1µm to 100µm) are cut from one side of the diamond layer 2. Specifically, laser cutting technology is used to cut slits of a certain depth and width (i.e., the first slit 5 and the second slit 6) on the surface of the diamond layer 2, penetrating the diamond layer 2 and extending into the substrate layer 1. Furthermore, the length direction of the first slit 5 is parallel to the upper surface of the diamond layer 2, and the depth direction of the first slit 5 is perpendicular to the upper surface of the diamond layer 2.
[0044] Selective etching is performed on the sample from the diamond layer 2. The etching material sequentially enters the substrate layer 1 through the first slit 5 and the second slit 6, performing isotropic etching on the substrate layer 1 to obtain microchannels 4, thus creating a microchannel heat dissipation structure. Specifically, an etching method that etches the substrate layer 1 but not the diamond layer 2 is selected. After etching for a certain period, the microchannel 4 structure is formed in the substrate layer 1. The bottom surface of the microchannel 4 is at a certain distance (1µm-1mm) from the ungrown surface of the substrate layer 1, away from the diamond layer 2.
[0045] Device layer 3 is grown on another polished surface of substrate layer 1. Specifically, high-quality device layer 3 material suitable for device fabrication with a thickness of 1-5 mm is grown on the substrate surface using CVD technology.
[0046] Furthermore, the substrate layer 1 was etched using XeF2 gas, KOH etchant, and HF etchant.
[0047] Example 1
[0048] S100 uses a 2-inch silicon substrate with a thickness of 500um and is double-sided polished.
[0049] S200, using MPCVD equipment, a polycrystalline diamond layer 2 with a thickness of 2mm is grown on a polished surface.
[0050] Specifically, the MPCVD growth parameters were: microwave frequency of 2.45 GHz, temperature of 800 degrees Celsius, methane flow rate of 5 sccm, hydrogen flow rate of 480 sccm, and chamber pressure of 60 torr.
[0051] S300: Using a femtosecond laser, the sample is cut from the diamond layer 2 to form a sample with a width of 80 μm and a depth that penetrates the diamond layer 2 and extends into the substrate layer 1. A first gap 5 is formed in the diamond layer 2, and a second gap 6 is formed in the substrate layer 1.
[0052] S400. The XeF2 gas etching system is used to etch the sample from the diamond layer 2. The gas enters the silicon substrate layer 1 through the first gap 5 and the second gap 6 to perform isotropic etching on the silicon. After etching for 1 hour, a microchannel 4 structure is formed. The spacing between two adjacent microchannels 4 is 5 μm.
[0053] S500, using MOCVD to grow high-quality GaN as device layer 3 on the other side, with a thickness of 5um.
[0054] Specifically, gallium nitride was grown using a mature standard process with a growth time of 1000s, a TMGa flow rate of 30 sccm, an NH3 flow rate of 5000 sccm, a temperature of 520℃, and a cavity pressure of 60 torr.
[0055] Electronic devices are fabricated in GaN device layer 3, and hot spots are placed below or near microchannel 4 to achieve efficient heat dissipation of the device.
[0056] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural transformations made based on the inventive concept of this utility model and the contents of this utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this utility model.
Claims
1. A microchannel heat dissipation structure, characterized in that, The microchannel heat dissipation structure includes: Substrate layer; A diamond layer is grown on one side of the substrate layer, and a first slot is formed through the diamond layer along the thickness direction of the diamond layer. The first slot is used to allow etching material to enter the substrate layer. Microchannels are disposed within the substrate layer and are obtained by isotropic etching of the substrate layer. A device layer, which is grown on the other side of the substrate layer.
2. In the microchannel heat dissipation structure according to claim 1, the number of the first gaps is multiple, and the multiple first gaps are spaced apart on the diamond layer.
3. The microchannel heat dissipation structure according to claim 2, wherein the substrate layer has a second slit along the thickness direction of the substrate layer, the first slit and the second slit overlap and are connected, and the etching material enters the substrate layer sequentially through the first slit and the second slit.
4. The microchannel heat dissipation structure according to claim 3, wherein the number of the second slits is multiple, and the number of the first slits and the number of the second slits are the same, and the multiple second slits are spaced apart on the substrate layer.
5. The microchannel heat dissipation structure according to claim 3, characterized in that, The widths of the first and second gaps range from 1µm to 100µm.
6. The microchannel heat dissipation structure according to claim 3, characterized in that, The depth of the first gap is equal to the thickness of the diamond layer, and the depth of the second gap is less than the thickness of the substrate layer.
7. The microchannel heat dissipation structure according to claim 1, characterized in that, The width of the microchannel is 10um-800um, and the spacing between two adjacent microchannels is 5um-5mm.
8. The microchannel heat dissipation structure according to claim 1, characterized in that, The thickness of the substrate layer is 50um-5mm.
9. The microchannel heat dissipation structure according to claim 1, characterized in that, The thickness of the diamond layer is 10um-10mm.
10. The microchannel heat dissipation structure according to claim 1, characterized in that, The thickness of the device layer is 1um-500um.