Phased-array antenna microsystem and LTCC (Low Temperature Co-Fired Ceramic) microchannel heat dissipation cold plate

Abstract

The utility model discloses a phased-array antenna microsystem and an LTCC (Low Temperature Co-Fired Ceramic) microchannel heat dissipation cold plate, an inner flow channel communicated with a cooling medium inlet and a cooling medium outlet is arranged in the LTCC microchannel heat dissipation cold plate, the inner flow channel comprises at least two headers used for distributing or collecting a cooling medium and microchannels, and the heads and tails of the microchannels are respectively connected with different headers. The micro-channels are arranged in groups and are distributed at intervals, the micro-channels are located on the second ceramic substrate, the collecting pipe is located on the third ceramic substrate, and the second ceramic substrate and the third ceramic substrate are stacked between the first ceramic substrate and the fourth ceramic substrate and are connected in a sintering mode; the phased-array antenna microsystem comprises a shell and the LTCC microchannel heat dissipation cold plate packaged in the shell. According to the utility model, the technical problems of large processing difficulty and limited liquid cooling efficiency of the existing LTCC heat dissipation micro-channel are solved, and a light-weight, miniaturized and accurate heat dissipation technical scheme is provided for micro-systems executing various functions, such as a phased-array antenna micro-system and the like.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit heat dissipation technology, and in particular to a phased array antenna microsystem and an LTCC microchannel heat dissipation cold plate. Background Technology

[0002] With the increasing multifunctionality and miniaturization of airborne equipment, the intelligentization of aircraft structures, and the development of drones and micro-aircraft, future airborne equipment and weapon systems will rely more heavily on highly integrated packaged devices. They will also widely adopt microsystem devices capable of performing various functions to improve performance and achieve lightweighting, miniaturization, and precision. Currently, when a large number of high-heat-generating devices are highly integrated, heat dissipation of these integrated components becomes a significant engineering challenge.

[0003] Compared to metal cold plates, LTCC material circuit boards offer superior high-frequency, high-quality factor, and high-speed transmission characteristics, along with fast digital response. They are also capable of withstanding high temperatures and handling large currents, making them ideal for microsystems and RF applications, and are widely used in the T / R components of modern active phased array antennas. However, due to the high integration of numerous high-heat-generating devices on LTCC material circuit boards, heat dissipation of these integrated components presents a significant engineering challenge. Traditional heat dissipation methods involve stacking metal cold plates on the LTCC material circuit board. However, regardless of the direction from which heat is transferred to the heat dissipation devices outside the component, it must pass through multiple layers of thermal resistance, such as ceramic substrate thermal resistance, multi-layer interface thermal resistance, filler thermal resistance, and package thermal resistance. This results in a relatively long heat transfer distance and limited cooling efficiency.

[0004] Therefore, Chinese invention patent application CN 118299820 A, with a publication date of July 5, 2024, discloses an integrated packaged phased array antenna microsystem, including a multi-signal processing substrate made of LTCC substrate. The LTCC substrate is provided with a flow channel for coolant flow. The flow channel includes at least two manifolds and microchannels connected to different manifolds at their ends. The manifolds include an inlet manifold, an outlet manifold, and a connecting manifold located between the two. The connecting manifold is connected to the inlet manifold and the outlet manifold through the microchannels.

[0005] The LTCC substrate in the aforementioned patent is a low-temperature co-fired ceramic substrate, formed by stacking and sintering ultra-thin ceramic strips. It allows for the organic integration of circuits, microchannels, passive devices, and surface-mount active chips across different ceramic layers, and can also fabricate curved structures. By designing heat dissipation microchannels within the LTCC substrate to form a microchannel heat sink, and by allowing all or part of the cooling medium to flow through the LTCC substrate, the heat transfer path is significantly shortened, interfacial thermal resistance is reduced, liquid cooling efficiency is improved, and a high degree of integration of heat-generating devices, power supply circuits, and heat dissipation microchannels is achieved.

[0006] However, the LTCC substrate in the aforementioned patent application has a manifold arrangement surface and a microchannel arrangement surface perpendicular to its thickness direction. The inlet manifold, outlet manifold, and connecting manifold are all located on the manifold arrangement surface. The microchannels extend from one manifold along the thickness direction of the LTCC substrate to the microchannel arrangement surface, and after extending within the microchannel arrangement surface, they extend along the thickness direction of the LTCC substrate to another manifold. Therefore, during LTCC substrate processing, due to the relatively small thickness of the LTCC substrate, the microchannels and manifolds are arranged along the thickness direction of the LTCC substrate, and the microchannels and manifolds are located on different surfaces inside the LTCC substrate, making the processing of the microchannels and manifolds quite difficult. Furthermore, due to the limitation of the thickness direction dimension, the cross-sectional area for coolant flow is small, limiting the liquid cooling efficiency.

[0007] It should be noted that the above technical information is intended only to enhance the understanding of the overall background technology of the present invention, and should not be regarded as an admission or in any way implying that the above technical information constitutes prior art known to those skilled in the art. Utility Model Content

[0008] To address the shortcomings in the aforementioned background technology, this utility model proposes a phased array antenna microsystem and an LTCC microchannel heat dissipation cold plate, which solves the technical problems of the high difficulty in fabricating heat dissipation microchannels for LTCCs and the limited liquid cooling efficiency.

[0009] The technical solution of this application is as follows:

[0010] An LTCC microchannel heat dissipation plate has an internal flow channel connected to a cooling medium inlet and a cooling medium outlet. The internal flow channel includes at least two manifolds for distributing or collecting the cooling medium and microchannels connected to different manifolds at their ends. The microchannels are arranged in groups and spaced apart. The microchannels are located on a second ceramic substrate, and the manifolds are located on a third ceramic substrate. The second and third ceramic substrates are stacked between a first and a fourth ceramic substrate and sintered together.

[0011] Based on the above technical solution, as a preferred technical solution, thermally conductive metal pillars for forming a thermally conductive network are provided between the ceramic substrate one, ceramic substrate two, ceramic substrate three, and ceramic substrate four.

[0012] Based on the above technical solutions, as a preferred technical solution, thermally conductive holes are provided on the ceramic substrate one, ceramic substrate two, ceramic substrate three, and ceramic substrate four, and the thermally conductive metal pillars are adapted to the thermally conductive holes.

[0013] Based on the above technical solution, as a preferred technical solution, the heat-conducting metal pillars are arranged in several groups, with each group of heat-conducting metal pillars arranged at intervals.

[0014] Based on the above technical solutions, as a preferred technical solution, the heat-conducting metal pillar is vertical and penetrates through ceramic substrate one, ceramic substrate two, ceramic substrate three, and ceramic substrate four.

[0015] Based on the above technical solutions, as a preferred technical solution, the thermally conductive metal pillars are arranged at intervals with the grouped microchannels and are located in the area between each group of microchannels.

[0016] Based on the above technical solutions, as a preferred technical solution, the manifold includes an inlet manifold, a connecting manifold, and an outlet manifold. The inlet manifold is connected to the cooling medium inlet for distributing the cooling medium, and the outlet manifold is connected to the cooling medium outlet for collecting the cooling medium. The grouped microchannels include a microchannel group connecting the inlet manifold and the connecting manifold, and a microchannel group connecting the connecting manifold and the outlet manifold. The cross-sectional area of ​​the inlet manifold gradually decreases along the cooling medium flow direction, and the cross-sectional area of ​​the outlet manifold gradually increases along the cooling medium flow direction.

[0017] Based on the above technical solutions, as a preferred technical solution, both the inlet manifold and the outlet manifold are stepped, and the inlet manifold and the outlet manifold are symmetrical.

[0018] Based on the above technical solutions, as a preferred technical solution, the cooling medium inlet and cooling medium outlet are arranged diagonally, with the cooling medium inlet located on the side facing ceramic substrate one or ceramic substrate four, and the cooling medium outlet located on the side facing ceramic substrate one or ceramic substrate four.

[0019] A phased array antenna microsystem includes a housing and a wave control board and a multi-signal processing substrate disposed within the housing. The housing includes an upper encapsulation housing, a lower encapsulation housing, and an electromagnetic isolation plate between the two. The multi-signal processing substrate is installed between the electromagnetic isolation plate and the upper isolation plate, and the wave control board is installed between the electromagnetic isolation plate and the lower isolation plate. The multi-signal processing substrate is the LTCC microchannel heat dissipation cold plate described in any of the above technical solutions.

[0020] Compared with the prior art, the technical solution disclosed in this utility model has the following beneficial effects:

[0021] 1. In the technical solution provided by this utility model, microchannels, manifolds, and cooling medium inlets and outlets are set on different ceramic substrates. The microchannels are arranged in groups, and each group corresponds to the position of the heat-generating device and the chip. The microchannels and manifolds are vertically connected to form a three-dimensional flow channel. On the one hand, the processing difficulty of the microchannels is reduced. On the other hand, the three-dimensional flow channel can place the chip or heating resistor and other heat-generating devices in the upper and lower areas of the microchannel for efficient heat dissipation, shorten the distance between the heat source and the cooling medium, and improve the heat dissipation effect. At the same time, the manifold can avoid the problem of excessive flow resistance caused by the long flow path of the cooling medium along the microchannel. The manifold reduces the length of the microchannel, and more numerous and denser microchannels can be set at the position corresponding to each heat-generating device while ensuring the aspect ratio of the microchannel, further enhancing the heat dissipation effect.

[0022] 2. In the technical solution provided by this utility model, thermally conductive metal pillars are set between each ceramic substrate to form a thermally conductive network. The thermally conductive metal pillars work together with the microchannels and manifolds to effectively improve the heat dissipation efficiency of each ceramic substrate layer, that is, to improve the overall thermal conductivity of the LTCC microchannel heat dissipation cold plate, thereby achieving efficient cooling of integrated circuits.

[0023] 3. In the technical solution provided by this utility model, an inlet manifold and an outlet manifold are arranged in the vertical direction of the microchannels to connect each microchannel. The cross-sectional area of ​​the inlet manifold gradually decreases along the flow direction of the cooling medium, while the cross-sectional area of ​​the outlet manifold gradually increases along the flow direction of the cooling medium. As the cooling medium flows, the pressure of the cooling medium decreases as it moves further from the inlet. The inlet manifold structure with a gradually decreasing cross-sectional area increases the pressure of the cooling medium flow and improves the flow velocity of the cooling medium. When the cooling medium flows in the three-dimensional channel, it continuously exchanges heat with the heat-generating device, resulting in a higher temperature when the cooling medium flows out of the three-dimensional channel. The greater the difference between the flow cross-section of the outlet and the flow cross-section of the inlet, the better the heat dissipation effect. The outlet manifold structure with a gradually increasing cross-sectional area increases the heat dissipation area of ​​the cooling medium. At the same time, the path length of the cooling medium along each microchannel is the same, making the heat exchange degree and flow velocity of the cooling medium at the outlet the same, reducing the pressure difference of the cooling medium before and after the outlet, and enhancing the heat dissipation effect of the cooling medium. Attached Figure Description

[0024] To more clearly illustrate the embodiments of this utility model, the drawings used in the description of the embodiments 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 these drawings without creative effort.

[0025] Figure 1 This is a three-dimensional structural diagram of an LTCC microchannel heat dissipation plate;

[0026] Figure 2 yes Figure 1 Exploded view;

[0027] Figure 3 yes Figure 2 A top view of the structure of the second ceramic substrate;

[0028] Figure 4 yes Figure 2 A top view of the three-layer ceramic substrate structure;

[0029] Figure 5 This is a schematic diagram of the structure after ceramic substrate 2 and ceramic substrate 3 are laminated;

[0030] Figure 6 This is a perspective view of an LTCC microchannel heat sink.

[0031] Figure 7 This is a simulation diagram of the heat dissipation effect of an LTCC microchannel heat sink.

[0032] Explanation of icon numbers:

[0033] Ceramic substrate 1, cooling medium inlet 1-1, cooling medium outlet 1-2, inlet connector 1-3, outlet connector 1-4;

[0034] Ceramic substrate 2, microchannel 2-1;

[0035] Ceramic substrate 3-3, inlet manifold 3-1, connecting manifold 3-2, outlet manifold 3-3;

[0036] Ceramic substrate 4;

[0037] 5. Thermally conductive metal pillar; 5-1.

[0038] Heating element 6;

[0039] Mounting hole 7. Detailed Implementation

[0040] 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 core concept of the present utility model and the following embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0041] Example 1: An LTCC microchannel heat dissipation plate, such as Figure 1 and Figure 2As shown, it has an internal flow channel that is connected to the cooling medium inlet 1-1 and the cooling medium outlet 1-2. The internal flow channel includes at least two manifolds for distributing or collecting the cooling medium and microchannels 2-1 that are connected to different manifolds at their ends. The microchannels 2-1 are arranged in groups and the groups are distributed at intervals.

[0042] The above structure is identical to the prior art patent technology of the applicant cited in the background section. The manifold includes an inlet manifold 3-1, an outlet manifold 3-3, and a connecting manifold 3-2 located between them. The inlet manifold 3-1 is connected to the cooling medium inlet 1-1 for distributing the cooling medium, and the outlet manifold 3-3 is connected to the cooling medium outlet 1-2 for collecting the cooling medium. The connecting manifold 3-2 is H-shaped. The H-shape of the connecting manifold 3-2 is to utilize the symmetrically arranged concave structure to avoid electronic components. The shape of the connecting manifold 3-2 can also be C-shaped, and the C-shaped connecting manifold 3-2 also has a concave structure for avoiding electronic components. A set of microchannels 2-1 is provided between the side of the connecting manifold 3-2 facing the inlet manifold 3-1 and the inlet manifold 3-1, and a set of microchannels 2-1 is also provided between the side of the connecting manifold 3-2 facing the outlet manifold 3-3 and the outlet manifold 3-3.

[0043] Simultaneously, it also has a manifold arrangement plane and a microchannel arrangement plane perpendicular to its thickness direction. The inlet manifold 3-1, outlet manifold 3-3, and connecting manifold 3-2 are all located on the manifold arrangement plane. The microchannel 2-1 extends from one manifold along the thickness direction of the entire device to the microchannel arrangement plane, and after extending within the microchannel arrangement plane, it extends along the thickness direction of the entire device to another manifold. Arranging the manifold and microchannel 2-1 in different planes is to prevent the microchannel 2-1 from interfering with the circuit and electronic components, and also to prevent the microchannel 2-1 and the manifold from being located on the same plane, which would cause insufficient strength of the entire device.

[0044] The unique feature of this embodiment lies in the following technical means: the microchannel 2-1 is located on ceramic substrate 2, the manifold is located on ceramic substrate 3, and ceramic substrate 2 and ceramic substrate 3 are stacked between ceramic substrate 1 and ceramic substrate 4 and sintered together. As for the cooling medium inlet 1-1 and cooling medium outlet 1-2, they can be simultaneously arranged on ceramic substrate 1, or on ceramic substrate 4, or one can be arranged on ceramic substrate 1 and the other on ceramic substrate 4. It should be specifically noted that when ceramic substrate 1, ceramic substrate 2, ceramic substrate 3, and ceramic substrate 4 are stacked sequentially, if ceramic substrate 3 is separated from cooling medium inlet 1-1 and cooling medium outlet 1-2 by ceramic substrate 2, then ceramic substrate 22 also has corresponding cooling medium inlet 1-1 and cooling medium outlet 1-2.

[0045] Specifically, in this embodiment, both the microchannel 2-1 and the manifold are manufactured using the LTCC process. The design of the LTCC channel should meet the requirements of the LTCC cavity design manual. The microchannel 2-1 is made by reducing the material on the ceramic substrate 1, and the manifold is made by reducing the material on the ceramic substrate 3. The microchannel 2-1 and the manifold are connected along the thickness direction of the ceramic substrates 2 and 3. Specific processing methods can include etching or laser processing, etc.

[0046] Furthermore, the microchannel 2-1 is used for efficient heat dissipation of the chip or heating resistor and other heat-generating devices 6 in corresponding areas on the ceramic substrate 1 and ceramic substrate 4. The microchannel 2-1 and the manifold respectively penetrate the thickness direction of the ceramic substrate 2 and ceramic substrate 3. After connecting the two ceramic substrates together, the microchannel 2-1 and the manifold are connected, forming a heat dissipation microchannel for the flow of the cooling medium. This increases the heat exchange area of ​​the microchannel 2-1 and reduces the processing difficulty of the heat dissipation microchannel. The heat dissipation microchannel is a three-dimensional flow channel, further shortening the distance between the cooling medium and the chip or heating resistor and other heat-generating devices 6, thus improving the heat dissipation effect.

[0047] Based on the above embodiments, as a preferred implementation of the LTCC microchannel heat dissipation cold plate, such as... Figures 3 to 5 As shown, the cooling medium inlet 1-1 is connected to the inlet manifold 3-1, and the cooling medium outlet 1-2 is connected to the outlet manifold 3-3. Two connecting manifolds 3-2 are arranged side-by-side between the inlet manifold 3-1 and the outlet manifold 3-3. Each connecting manifold 3-2 forms an independent flow path. After the cooling medium flows from the cooling medium inlet 1-1 through the inlet manifold 3-1, it enters a relatively independent flow path: that is, it flows sequentially through one set of microchannels 2-1, the connecting manifold 3-2, and another set of microchannels 2-1, then enters the outlet manifold 3-3, and finally flows out from the cooling medium outlet 1-2. The position of the microchannels 2-1 is vertically aligned with the position of the heating element 6 on the outer ceramic substrate, and the manifolds are vertically aligned with the position of the non-heating element 6 on the outer ceramic substrate. This reduces the processing difficulty and the length of the microchannels 2-1, thereby improving the cooling effect. In this embodiment, the cooling medium can circulate between the cooling medium inlet 1-1 and the cooling medium outlet 1-2. It is only necessary to connect an external cooling device to cool the cooling medium again and use a circulation device to recycle the cooling medium.

[0048] Based on the above embodiments, as a preferred embodiment of the LTCC microchannel heat dissipation cold plate, thermally conductive metal pillars 5 for forming a heat-conducting network are provided between the ceramic substrate 1, ceramic substrate 2, ceramic substrate 3, and ceramic substrate 4.

[0049] Preferably, thermally conductive holes 5-1 are provided on the ceramic substrate 1, ceramic substrate 2, ceramic substrate 3, and ceramic substrate 4, and the thermally conductive metal pillar 5 is adapted to the thermally conductive holes 5-1.

[0050] More preferably, the heat-conducting metal pillars 5 are provided in several groups, and the heat-conducting metal pillars 5 in each group are arranged at intervals.

[0051] More preferably, the thermally conductive metal pillar 5 is vertical and penetrates through ceramic substrate 1, ceramic substrate 2, ceramic substrate 3, and ceramic substrate 4.

[0052] More preferably, the thermally conductive metal pillar 5 is arranged at intervals with the grouped microchannels 2-1 and is located in the region between each group of microchannels 2-1.

[0053] In the above embodiment, thermally conductive metal pillars 5 are provided between each ceramic substrate to form a thermally conductive network. The thermally conductive metal pillars 5, together with the microchannels 2-1 and the manifold, effectively improve the heat dissipation efficiency of each ceramic substrate layer, that is, improve the overall thermal conductivity of the LTCC microchannel heat dissipation cold plate, thereby achieving efficient cooling of the integrated circuit.

[0054] Based on the above embodiments, as a preferred implementation of the LTCC microchannel heat dissipation plate, the heat exchange area of ​​each group of microchannels 2-1 is larger than the heat exchange area of ​​the manifold. Specifically, the manifold can reduce the length of the microchannels 2-1, and while ensuring the aspect ratio of the microchannels 2-1, more channels can be set at the positions corresponding to each heat-generating device 6, further enhancing the heat dissipation effect.

[0055] The manifold is used to connect the various microchannels 2-1, reducing the flow resistance of the cooling medium, reducing the pressure drop, and thus enhancing the heat dissipation effect. Furthermore, the heat exchange area of ​​the manifold can be reduced by increasing its cross-sectional area, thereby avoiding the problem of excessive flow resistance caused by a long flow path of the cooling medium along the microchannels 2-1.

[0056] Based on the above embodiments, as a preferred embodiment of the LTCC microchannel heat dissipation plate, each group of microchannels 2-1 is arranged in parallel, and each group of microchannels 2-1 is connected through a manifold along the flow direction of the microchannels 2-1.

[0057] Each group of microchannels 2-1 and connecting manifolds 3-2 are arranged in parallel. The connecting manifolds 3-2 connect two adjacent microchannels 2-1 only in the parallel direction of the microchannels 2-1, which further reduces the flow path of the cooling medium along the microchannels 2-1 and avoids the problem of excessive flow resistance caused by a long flow path of the cooling medium along the microchannels 2-1. At the same time, the connecting manifolds 3-2 reduce the length of the microchannels 2-1, which allows for the arrangement of more channels at the corresponding positions of each heat-generating device 6 while ensuring the aspect ratio of the microchannels 2-1, thereby further enhancing the heat dissipation effect.

[0058] Furthermore, when the microchannels 2-1 are configured as three sets in a triangular shape, the three sets of microchannels 2-1 are arranged in parallel, and the connecting manifold 3-2 connects two adjacent microchannels 2-1 along the parallel direction of the microchannels 2-1. The direction of the connecting manifold 3-2 can be arbitrarily set. Preferably, the direction of the connecting manifold 3-2 is set along the line connecting two microchannels 2-1 to reduce the flow path of the cooling medium.

[0059] Based on the above embodiments, as a preferred embodiment of the LTCC microchannel heat dissipation plate, such as... Figure 5 As shown, when the microchannels 2-1 are arranged in four quadrilateral groups, the four groups of microchannels 2-1 are used to dissipate heat from the heat-generating devices 6 located above and / or below them. At intervals between the heat-generating devices 6, connecting manifolds 3-2 are provided to connect the microchannels, and the flow direction of the connecting manifolds 3-2 is parallel to the flow direction of the microchannels 2-1.

[0060] When dissipating heat from the heat-generating device 6, the cooling medium flows from the cooling medium inlet 1-1 through the inlet manifold 3-1 and then enters two sets of microchannels 2-1. The cooling medium in the two sets of microchannels 2-1 enters two connecting manifolds 3-2, and the cooling medium in the two connecting manifolds 3-2 enters another two sets of microchannels 2-1. Then the cooling medium is collected in the outlet manifold 3-3, and finally the cooling medium flows out from the cooling medium outlet 1-2, completing one heat dissipation cycle.

[0061] In this embodiment, the cooling medium can circulate between the cooling medium inlet 1-1 and the cooling medium outlet 1-2. It is only necessary to connect an external cooling device to cool the cooling medium again and use a circulation device to recycle the cooling medium.

[0062] Specifically, such as Figure 2 and Figure 6 As shown, in this embodiment, each of the four sets of microchannels 2-1 is provided with 5 microchannel branches. The cross-sectional shape of the microchannel branches is rectangular. In this embodiment, the connecting manifolds 3-2 are all I-shaped. The two ends of the I-shape are perpendicularly connected to the microchannels 2-1. The cross-sectional area of ​​the middle part of the I-shape is larger than the cross-sectional area of ​​any one of the four sets of microchannels 2-1. While ensuring that the microchannels 2-1 cover the heating device 6, the connecting manifolds 3-2 should be as long as possible.

[0063] While ensuring that the microchannel 2-1 covers the heating device 6, the length of the connecting manifold 3-2 is increased to reduce the length of the microchannel 2-1, thus avoiding excessive flow resistance and weakened heat dissipation when the microchannel 2-1 is too long. The heat exchange effect is enhanced by increasing the number of microchannel branches in each group of microchannels 2-1. The number of microchannel branches is set according to the power and projected area of ​​the heating device 6 to achieve precise heat exchange for the heating device 6.

[0064] Based on the above embodiments, as a preferred implementation of the LTCC microchannel heat dissipation plate, the design of the LTCC flow channels should, while meeting the requirements of the LTCC cavity design manual, arrange a sufficient number of microchannels 2-1 below the heat source. For the structural design of the microchannel branches in each group of microchannels 2-1, the cross-section of the microchannel branch should have a sufficient aspect ratio, i.e., height-to-width ratio. Simultaneously, since the cross-sectional area of ​​the microchannel branches is very small, their length needs to be minimized; otherwise, excessive flow resistance will occur if the distance is too long. Regarding the length of the microchannel branches, the shorter the length, the lower the flow resistance of the cooling medium within it, and the better the heat dissipation effect of the microchannel branches. Regarding the spacing of the microchannel branches, under the same projected area, the more microchannel branches there are, the better the heat dissipation performance; therefore, it is preferable to process as many microchannel branches as possible within the corresponding area. Therefore, it is preferable to set the height-to-width ratio of the microchannel branches to 2, and preferably to set the width of the microchannel branches to 0.5 mm and the height to 1 mm. In a limited space, the aspect ratio of the microchannel should be increased as much as possible, that is, the aspect ratio of microchannel 2-1 can be other values.

[0065] like Figure 7 As shown, the heat dissipation effect of the LTCC microchannel heat sink was simulated. When the overall size of the LTCC microchannel heat sink is 70×70mm, the width of the microchannel branch is set to 0.5mm, the height of the microchannel branch is set to 1mm, the wall thickness of the microchannel branch is 0.5mm, and each group of microchannels 2-1 has 5 microchannel branches, the heat flux density is 3.57W / cm². 2 Under these conditions, the simulation results show that the maximum temperature of the heating device 6 is 47.88677℃, which meets the requirement of ≤65℃ and satisfies the temperature requirements of integrated circuits.

[0066] Preferably, the number and position of the microchannels 2-1 are determined according to the number and position of the heating elements 6. The number of microchannels 2-1 corresponds to the number of heating elements 6, and the position of each group of microchannels 2-1 is aligned vertically with the position of the heating element 6. The length of each group of microchannels 2-1 is set according to the projected length of the heating element. The number of microchannel branches in each group of microchannels 2-1 is set according to the projected width of the heating element and the power of the heating element 6. The cross-sectional shape of the microchannel branches can be rectangular, triangular, trapezoidal, or a combination of the above shapes or other arbitrary shapes.

[0067] Based on the above embodiments, as a preferred embodiment of the LTCC microchannel heat dissipation cold plate, the manifold 28 includes an inlet manifold 21 connected to the cooling medium inlet 1-1 and an outlet manifold 3-3 connected to the cooling medium outlet 1-2. The cross-sectional area of ​​the inlet manifold 21 gradually decreases along the flow direction of the cooling medium, and the cross-sectional area of ​​the outlet manifold 3-3 gradually increases along the flow direction of the cooling medium.

[0068] The inlet manifold 21 connects the upstream of the cooling medium inlet 1-1 and the microchannel 2-1, while the outlet manifold 3-3 connects the downstream of the cooling medium outlet 1-2 and the microchannel 2-1. In this embodiment, the inlet manifold 21 and the outlet manifold 3-3 can further reduce the length of the microchannel 2-1, thereby reducing flow resistance.

[0069] Meanwhile, as the cooling medium flows, the pressure decreases further away from the inlet 1-1. By gradually reducing the cross-sectional area of ​​the inlet manifold 3-1 along the flow direction of the cooling medium, the flow cross-sectional area of ​​the cooling medium can be gradually reduced, thereby increasing the pressure. Conversely, by gradually increasing the cross-sectional area of ​​the outlet manifold 3-3 along the flow direction of the cooling medium, the cooling medium continuously exchanges heat with the heat-generating device 6 as it flows in the three-dimensional flow channel. This results in a higher temperature of the cooling medium when it exits the three-dimensional flow channel. The larger the cross-sectional area of ​​the outlet manifold 3-3 compared to the inlet, the larger the heat dissipation area of ​​the cooling medium, and the better the heat dissipation effect of the cooling medium.

[0070] Based on the above embodiments, as a preferred embodiment of the LTCC microchannel heat dissipation cold plate, both the inlet manifold 3-1 and the outlet manifold 3-3 are stepped, and the inlet manifold 3-1 and the outlet manifold 3-3 are centrally symmetrical.

[0071] Preferably, the inlet manifold 3-1 and outlet manifold 3-3 are stepped according to the position of each group of microchannels 2-1. For the inlet manifold, this is because as the cooling medium flows downstream from each group of microchannels 2-1 to the cooling medium outlet 1-2, the pressure of the cooling medium flowing out of each group of microchannels 2-1 gradually decreases with each step, which can further equalize the pressure of the cooling medium in each group of microchannels 2-1. This reduces the pressure difference when each group of microchannels 2-1 reaches the cooling medium outlet manifold 3-3, enhancing the heat dissipation effect of the cooling medium. For the outlet manifold 3-3, the purpose is to ensure that the flow path of the cooling medium from the cooling medium inlet 1-1 to the cooling medium outlet 1-2 is a zigzag shape, and that the cooling medium flowing through each group of microchannels 2-1 has the same heat exchange distance, so that the heat exchange degree of the cooling medium flowing through each group of microchannels 2-1 is the same; at the same time, it further reduces the pressure difference of the cooling medium from each group of microchannels 2-1 in the outlet manifold 3-3, thereby enhancing the heat dissipation effect of the cooling medium.

[0072] The LTCC cold plate features a three-dimensional microchannel system distributed throughout the middle of the module, providing heat dissipation for devices and chips placed in the upper and lower areas. The cooling medium first flows into the stepped inlet manifold 3-1 from the inlet, then into 10 microchannel branches. By increasing the number of channels, more heat is carried away. Every five branches converge into a type I connecting manifold 3-2, which solves the problem of excessive flow resistance caused by long flow distances. After being collected, the coolant flows out from the 10 branches again, converging into the stepped outlet manifold 3-3 on the other side, and finally exits from the cooling medium outlet 1-2.

[0073] Based on the above embodiments, in a preferred embodiment of the LTCC microchannel heat dissipation cold plate, the cooling medium inlet 1-1 and the cooling medium outlet 1-2 are arranged diagonally. The cooling medium inlet 1-1 is located on the side facing the ceramic substrate 1 or ceramic substrate 4, and the cooling medium outlet 1-2 is located on the side facing the ceramic substrate 1 or ceramic substrate 4. The cooling medium inlet 1-1 and the cooling medium outlet 1-2 are respectively connected to the inlet connector 1-3 and the outlet connector 1-4. The inlet connector 1-3 and the outlet connector 1-4 are welded to the corresponding ceramic substrates using dissimilar materials, and are connected to the external liquid cooling system through a reasonable sealing structure and fluid connector.

[0074] A phased array antenna microsystem includes a housing and a wave control board and a multi-signal processing substrate disposed within the housing. The housing includes an upper encapsulation housing, a lower encapsulation housing, and an electromagnetic isolation plate between the two. The multi-signal processing substrate is installed between the electromagnetic isolation plate and the upper isolation plate, and the wave control board is installed between the electromagnetic isolation plate and the lower isolation plate. The multi-signal processing substrate is the LTCC microchannel heat dissipation cold plate described in any of the above embodiments.

[0075] Preferably, mounting holes 7 are provided through the ceramic substrate 1, ceramic substrate 2, ceramic substrate 3, and ceramic substrate 4, and the LTCC microchannel heat dissipation plate is connected between the electromagnetic isolation plate and the upper isolation plate through the mounting holes.

[0076] Preferably, the LTCC microchannel heat dissipation plate can be encapsulated in the housing, and heat dissipation microchannels are provided inside the housing to achieve simultaneous cooling of the upper and lower layers of the heat-generating device 6.

[0077] Any aspects of this utility model that are not detailed herein are conventional technical means known to those skilled in the art.

[0078] The above content shows and describes the basic principles, main features, and beneficial effects of this utility model. The above description is merely a preferred embodiment of this utility model and is not intended to limit it. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An LTCC microchannel heat dissipation plate, comprising an internal flow channel communicating with a cooling medium inlet (1-1) and a cooling medium outlet (1-2), the internal flow channel including at least two manifolds for distributing or collecting the cooling medium and microchannels (2-1) connected at their ends to different manifolds, the microchannels (2-1) being arranged in groups and spaced apart, characterized in that: The microchannel (2-1) is located on ceramic substrate two (2), the manifold is located on ceramic substrate three (3), and ceramic substrate two (2) and ceramic substrate three (3) are stacked between ceramic substrate one (1) and ceramic substrate four (4) and sintered together.

2. The LTCC microchannel heat dissipation plate according to claim 1, characterized in that: A heat-conducting metal pillar (5) for forming a heat-conducting network is provided between the ceramic substrate one (1), ceramic substrate two (2), ceramic substrate three (3), and ceramic substrate four (4).

3. The LTCC microchannel heat dissipation plate according to claim 2, characterized in that: The ceramic substrate one (1), ceramic substrate two (2), ceramic substrate three (3) and ceramic substrate four (4) are provided with heat-conducting holes (5-1), and the heat-conducting metal pillar (5) is adapted to the heat-conducting holes (5-1).

4. The LTCC microchannel heat dissipation plate according to claim 2 or 3, characterized in that: The heat-conducting metal pillars (5) are arranged in several groups, with each group of heat-conducting metal pillars (5) arranged at intervals.

5. The LTCC microchannel heat dissipation plate according to claim 4, characterized in that: The heat-conducting metal column (5) is vertical and penetrates through ceramic substrate one (1), ceramic substrate two (2), ceramic substrate three (3), and ceramic substrate four (4).

6. The LTCC microchannel heat dissipation plate according to any one of claims 2, 3, and 5, characterized in that: The thermally conductive metal pillar (5) is arranged at intervals with the grouped microchannels (2-1) and is located in the area between each group of microchannels (2-1).

7. The LTCC microchannel heat dissipation plate according to claim 6, characterized in that: The manifold includes an inlet manifold (3-1), a connecting manifold (3-2), and an outlet manifold (3-3). The microchannels (2-1) arranged in groups include a microchannel group connecting the inlet manifold (3-1) and the connecting manifold (3-2), and a microchannel group connecting the connecting manifold (3-2) and the outlet manifold (3-3). The cross-sectional area of ​​the inlet manifold (3-1) gradually decreases along the flow direction of the cooling medium, and the cross-sectional area of ​​the outlet manifold (3-3) gradually increases along the flow direction of the cooling medium.

8. The LTCC microchannel heat dissipation plate according to claim 7, characterized in that: Both the inlet manifold (3-1) and the outlet manifold (3-3) are stepped, and the inlet manifold (3-1) and the outlet manifold (3-3) are centrally symmetrical.

9. The LTCC microchannel heat dissipation plate according to any one of claims 1, 3, 5, 7, and 8, characterized in that: The cooling medium inlet (1-1) and cooling medium outlet (1-2) are arranged diagonally. The cooling medium inlet (1-1) is located on the side facing the ceramic substrate one (1) or the ceramic substrate four (4), and the cooling medium outlet (1-2) is located on the side facing the ceramic substrate one (1) or the ceramic substrate four (4).

10. A phased array antenna microsystem, comprising a housing and a wave control board and a multi-signal processing substrate disposed within the housing, the housing comprising an upper encapsulation housing, a lower encapsulation housing, and an electromagnetic isolation plate between the two, wherein the multi-signal processing substrate is installed between the electromagnetic isolation plate and the upper isolation plate, and the wave control board is installed between the electromagnetic isolation plate and the lower isolation plate, characterized in that: The multi-signal processing substrate is the LTCC microchannel heat dissipation cold plate as described in any one of claims 1-9.

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