Microchannel heat sink

Abstract

A micro-channel radiator comprises a silicon base plate and a packaging plate. The silicon base plate and the packaging plate are bonded to each other to form a sealed space, which is divided into a pin rib area, a micro-channel area and a confluence area along the diameter of the silicon base plate. The center of the packaging plate is provided with a cooling working medium inlet, and the sidewall of the packaging plate is provided with a plurality of cooling working medium outlets. The pin rib area comprises a plurality of cylindrical pin ribs and a plurality of inclined triangular prism pin ribs, and the inclined triangular prism pin ribs are arranged outside the cylindrical pin ribs. The micro-channel area is provided with a micro-channel heat sink, and the upper part of the micro-channel heat sink is provided with a heat sink circular ring inlet. The micro-channel heat sink is divided into two layers, and a plurality of intersecting micro-channels are arranged on each layer of the micro-channel heat sink. A plurality of heat sink outlets are arranged on the edge of the micro-channel heat sink. The flow direction of the fluid in the channel is changed through the plurality of intersecting micro-channels, so that the heat exchange uniformity is achieved, and local high-temperature hot spots of the radiator are avoided.

Description

Technical Field

[0001] This invention belongs to the field of heat sink technology, and specifically relates to a microchannel heat sink. Background Technology

[0002] The world's first commercially available chip, the Intel 4004, had only 2,300 electronic components. Today, my country's Etian 710 chip boasts 60 billion electronic components. With the rapid development of integrated circuit engineering and semiconductor chip technology, microelectronic chips are evolving towards faster computing speeds and greater power. The increasing integration of electronic components leads to a dramatic rise in heat flux density and rapid temperature accumulation on the chip. Currently, the heat flux density generated by microelectronic chips exceeds 100 W / cm². 2 If heat cannot be dissipated from the chip in time, it will lead to a decrease in the reliability of many components on the chip, local warping of the chip itself, a reduction in the chip's lifespan, a significant increase in the chip failure rate, and even damage to the entire chip, causing electronic devices to malfunction and resulting in huge economic losses. Therefore, heat dissipation of microelectronic chips has become an urgent problem to be solved. Microchannel heat sink technology is an effective method for solving the heat dissipation problem of integrated circuits. Microchannel heat sinks have the advantages of small size, high heat dissipation efficiency, and large heat transfer area.

[0003] Early scholars mainly studied the flow and heat transfer characteristics of traditional rectangular straight channel heat sinks. Their heat dissipation capacity is limited, and the heat dissipation effect on high-power chips is not good. The heat transfer uniformity along the fluid flow direction is poor, which makes it easy for high-temperature hot spots to form in some parts of the heat sink. Summary of the Invention

[0004] Purpose of the invention: To address the problem that traditional rectangular straight-channel heat sinks have limited heat dissipation capacity, poor heat dissipation effect on high-power chips, and poor heat transfer uniformity along the fluid flow direction, which makes it easy for high-temperature hot spots to form in some parts of the heat sink, a microchannel heat sink is proposed.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a microchannel heat sink, comprising: a silicon substrate and a packaging plate, wherein the silicon substrate and the packaging plate are bonded together to form a sealed space, and the sealed space is divided into a pin rib area, a microchannel heat sink area and a confluence area along the diameter of the silicon substrate.

[0006] A cooling medium inlet is provided at the center of the encapsulation plate, and a plurality of cooling medium outlets communicating with the confluence zone are provided on the outer circumference of the sealed space.

[0007] The needle rib area includes a plurality of oblique triangular prism needle ribs arranged in a ring, and a plurality of oblique triangular prism needle ribs located inside the ring.

[0008] The microchannel heat sink area adopts a double-layer microchannel structure, each layer is composed of petal-shaped microchannel structural units arranged in a ring array; the petal-shaped microchannel structural unit is composed of two intersecting microchannels, and there are at least two intersecting areas. The inlets of the two microchannels are connected to the needle rib area, and the outlets of the two microchannels are connected to the confluence area.

[0009] The upper and lower petal-shaped microchannel structural units are staggered and partially overlap each other along the circumferential direction, and the microchannels at the overlapping points are interconnected in the vertical direction.

[0010] Furthermore, a plurality of the cylindrical pin ribs are arrayed along the center of the silicon substrate to form a cylindrical pin rib region, and a plurality of the oblique triangular prism pin ribs are arrayed in a ring along the edge of the cylindrical pin rib region to form an oblique triangular prism pin rib region.

[0011] Furthermore, the radius of the silicon substrate is 5-12 mm.

[0012] Furthermore, the radius of the cylindrical needle rib is 0.03-0.08 mm, the height of the cylindrical needle rib is 0.3-0.8 mm, and the number of layers of the cylindrical needle rib is 4-7.

[0013] Furthermore, the bottom side length of the oblique triangular prism needle rib is 0.12-0.18 mm, the height of the oblique triangular prism needle rib is 0.3-0.8 mm, the number of layers of the oblique triangular prism needle rib is 1-5, and the distance between each layer is 0.15-0.5 mm.

[0014] Furthermore, the height of each layer of the microchannel heat sink is 0.25 mm, and the width of the microchannel is 0.1-0.35 mm.

[0015] Furthermore, the heat sink outlets are arranged alternately on the outer wall of the microchannel heat sink.

[0016] Furthermore, the microchannel region surrounds the needle rib region, and the confluence region surrounds the microchannel region.

[0017] Beneficial effects:

[0018] 1. By adjusting the number of microchannels and the structural dimensions in the upper and lower heat sinks, the area for convective heat transfer is increased to meet different heat dissipation needs, while improving the heat transfer uniformity of the radiator and enhancing heat transfer.

[0019] 2. By setting intersecting microchannels on the same layer of the microchannel heat sink and connecting the overlapping parts of adjacent intersecting microchannels in two layers, the fluid flow direction in the intersecting microchannels in the upper and lower layers of the microchannel heat sink is changed, which enhances the turbulence of the fluid inside the channel, promotes the mixing of hot and cold fluids, improves the heat exchange uniformity of the fluid in the intersecting microchannels, avoids the formation of local high-temperature hot spots in the radiator, and improves the heat transfer efficiency.

[0020] 3. With the cooling medium inlet located at the center of the packaging board, the cooling medium directly impacts the cylindrical pin rib area above the heat source and the bottom surface of the silicon substrate, and flows rapidly to the surrounding area. At this time, the temperature of the cooling medium is at its lowest, effectively reducing the temperature of the heat source area at the inlet. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall disassembled structure of a microchannel heat sink;

[0022] Figure 2 This is a schematic diagram of a packaging board structure for a microchannel heat sink.

[0023] Figure 3 This is a top view of the overall internal structure of a microchannel heat sink.

[0024] Figure 4 This is a schematic diagram of a microchannel heat sink structure for a microchannel heat sink.

[0025] Figure 5 This is a top view of part of the internal structure of a microchannel heat sink.

[0026] In the diagram: 1. Silicon substrate, 2. Packaging board, 3. Coolant inlet, 4. Coolant outlet, 5. Pin rib area, 5.1. Cylindrical pin rib, 5.2. Oblique triangular prism pin rib, 6. Microchannel area, 7. Confluence area, 8. Radiator ring inlet, 9. Heat sink ring inlet, 10. Microchannel heat sink, 11. Petal-shaped microchannel structural unit, 12. Intersecting microchannels, 12.1. Upper intersecting microchannels, 12.2. Lower intersecting microchannels, 13. Intersecting connected area, 13.1. First intersecting area, 13.2. Second intersecting area, 13.3. Third intersecting area, 13.4. Fourth intersecting area, 14. Heat sink outlet. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1-5 The present invention will be further explained below.

[0028] Please see Figure 1-2 This invention provides a microchannel heat sink, comprising: a silicon substrate 1 and an encapsulation plate 2. The silicon substrate 1 and the encapsulation plate 2 are bonded together to form a sealed space. The sealed space is divided from the center of the silicon substrate 1 along the direction of the cooling fluid flow into a pin fin region 5, a microchannel region 6, and a confluence region 7.

[0029] A cooling medium inlet 3 is provided at the center of the encapsulation plate 2. Several cooling medium outlets 4 are provided on the side wall of the encapsulation plate 2, and they are evenly distributed. The cooling medium flows in from the cooling medium inlet 3, then flows through the needle rib area 5, the microchannel area 6 and the confluence area 7 in sequence, and finally flows out from the cooling medium outlet 4.

[0030] The pin rib region 5 is located at the center of the silicon substrate 1, the microchannel region 6 surrounds the pin rib region 5, and the confluence region 7 surrounds the microchannel region 6.

[0031] The pin rib region 5 includes several cylindrical pin ribs 5.1 and several oblique triangular prism pin ribs 5.2. The area containing the cylindrical pin ribs 5 is the cylindrical pin rib region, and the area containing the oblique triangular prism pin ribs 5.2 is the oblique triangular prism pin rib region. A radiator annular inlet 8 is located below the cooling medium inlet 3. The cylindrical pin rib region is located inside the radiator annular inlet 8, and the oblique triangular prism pin rib region is located between the radiator annular inlet 8 and the heat sink annular inlet 9. The cooling medium directly impacts the cylindrical pin ribs 5.1 of the pin rib region 5 above the heat source and the bottom surface of the silicon substrate 1, and flows rapidly to the surrounding areas. At this point, the temperature of the cooling medium is at its lowest, effectively reducing the temperature of the heat source area at the inlet. The oblique triangular prism pin ribs 5.2 are used to disturb and divert the flowing cooling medium.

[0032] A microchannel heat sink 10 is installed within the microchannel region 6. The center of the microchannel heat sink 10 has a hollow area. The microchannel heat sink 10 consists of two layers, each layer having several intersecting microchannels 12. The inlets of the intersecting microchannels 12 form a circular inlet 9 along the edge of the hollow area, and the outlets of the intersecting microchannels 12 are distributed along the edge of the microchannel heat sink 10, forming several staggered heat sink outlets 14. The cooling medium flows into the intersecting microchannels 12 on the microchannel heat sink 10 through the circular inlet 9, and then flows out from the heat sink outlets 14 at the edge of the microchannel heat sink 10.

[0033] The confluence zone 7 is surrounded by the edge of the microchannel heat sink, the silicon substrate and the packaging board. The cooling medium flows into the confluence zone 7 from the heat sink outlet 14 and then flows out from the confluence zone 7 through the cooling medium outlet 4.

[0034] In this embodiment, the silicon substrate 1 is a circular substrate. The radius of the silicon substrate 1 is 5-12 mm, preferably 7 mm. Both the cooling medium inlet 3 and the cooling medium outlet 4 are circular. There is one cooling medium inlet 3 and ten cooling medium outlets 4. The microchannel heat sink 10 is annular.

[0035] Please see Figure 3-4Within the rib region, a plurality of cylindrical ribs 5.1 are arrayed along the center of the silicon substrate 1 to form a cylindrical rib region, allowing the incoming cooling medium to flow uniformly in all directions. A plurality of oblique triangular prism ribs 5.2 surround the outer side of the plurality of cylindrical ribs 5.1, and the plurality of oblique triangular prism ribs 5.2 are arrayed in a ring along the edge of the cylindrical rib region to form an oblique triangular prism rib region, allowing the incoming cooling medium to be evenly distributed, thereby facilitating its entry into the intersecting microchannels 12. Within the microchannel region 6, the microchannel heat sink 10 is divided into upper and lower layers, and each layer of the microchannel heat sink 10 is provided with a plurality of intersecting microchannels 12. The plurality of intersecting microchannels 12 in the same layer are arrayed in a ring along the edge of the hollow region to form petal-shaped microchannel structural units 11. The intersecting microchannels 12 located in adjacent layers are staggered, partially overlapped and connected, wherein the two ends of the intersecting microchannels 12 are connected to the heat sink annular inlet 9 and the heat sink outlet 14, respectively. Cross-connection regions 13 are formed at the intersection of each intersecting microchannel 12 and at the connection points of adjacent intersecting microchannels 12 in two layers. By setting intersecting microchannels 12 on the same layer of the microchannel heat sink 10 and connecting the overlapping parts of adjacent intersecting microchannels 12 in two layers, the flow direction of the cooling medium in the intersecting microchannels 12 in the upper and lower layers of the microchannel heat sink 10 is changed, which enhances the turbulence of the fluid inside the channel, promotes the mixing of hot and cold fluids, improves the heat exchange uniformity of the fluid in the intersecting microchannels 12, avoids the formation of local high-temperature hot spots in the radiator, and improves the heat transfer efficiency.

[0036] In this embodiment, the radius of the cylindrical needle rib 5.1 is 0.03-0.08 mm, preferably 0.05 mm. The height of the cylindrical needle rib 5.1 is 0.3-0.8 mm, preferably 0.5 mm. Four to seven layers of cylindrical needle ribs 5.1 are provided in the cylindrical needle rib area according to the flow direction of the cooling medium, preferably five layers. The first layer has one cylindrical needle rib, the second layer has five, the third layer has ten, the fourth layer has fifteen, and the fifth layer has twenty. The bottom side length of the oblique triangular prism needle rib 5.2 is 0.12-0.18 mm, preferably 0.15 mm. The height of the oblique triangular prism needle rib 5.2 is 0.3-0.8 mm, preferably 0.5 mm. The oblique triangular prism needle rib area is provided with 1-5 layers of oblique triangular prism needle ribs 5.2 in accordance with the flow direction of the cooling working fluid, and the distance between each layer is 0.15-0.5 mm, preferably 2 layers, and the number of oblique triangular prism needle ribs in each layer is 30.

[0037] The intersecting microchannels 12 include an upper intersecting microchannel 12.1 and a lower intersecting microchannel 12.2. The upper intersecting microchannel 12.1 is located above the lower intersecting microchannel 12.2, and both the upper intersecting microchannel 12.1 and the lower intersecting microchannel 12.2 are disposed on the microchannel heat sink 10. The width of the intersecting microchannels 12 is 0.1-0.35 mm, preferably 0.15 mm. The microchannel heat sink 10 has two layers, each layer of which has a height of 0.25 mm, and each layer of the microchannel heat sink 10 has 30 intersecting microchannels 12.

[0038] Please see Figure 5 The cross-connected region 13 includes a first cross-connected region 13.1, a second cross-connected region 13.2, a third cross-connected region 13.3, and a fourth cross-connected region 13.4. These four regions are sequentially positioned on the microchannel heat sink 10 according to the flow direction of the cooling medium. The first cross-connected region 13.1 and the fourth cross-connected region 13.4 are formed by the vertical connection of two adjacent intersecting microchannels 12 located in two layers. The second cross-connected region 13.2 and the third cross-connected region 13.3 are formed by the mutual intersection of two microchannels in the same layer of intersecting microchannels 12. The flow direction of the cooling medium changes in the cross-connected region 13, flowing into the intersecting microchannels 12 in another layer of the microchannel heat sink 10 or into the intersecting microchannels 12 in the same layer. This promotes thorough mixing of the hot and cold fluids, disrupts the thermal boundary layer, increases the area for convective heat transfer, improves the heat transfer uniformity of the radiator, and enhances its heat transfer performance.

[0039] The cooling medium mentioned above is deionized water, pure water, ethanol, or ethylene glycol. The microchannel heat sink 10 is made of silicon, which has good thermal conductivity. Alternatively, materials such as silver, copper, aluminum, iron, and diamond can be used depending on the specific requirements. The dimensions of the microchannel heat sink 10 and the number, size, and spacing of the petal-shaped microchannel structural units 11 can be determined based on actual heat transfer requirements and flow conditions.

[0040] The working principle of this embodiment is as follows:

[0041] The cooling medium enters the cylindrical needle rib region through the cooling medium inlet 3, impacts the cylindrical needle rib region and the bottom silicon substrate 1, and then enters the oblique triangular prism needle rib region. After being disturbed and diverted in the oblique triangular prism needle rib region 5.2, it enters the intersecting microchannel 12 in the upper and lower petal-shaped microchannel structure units 11.

[0042] Then, the flow direction of the cooling medium changes in the intersection region 13 of the intersecting microchannels 12 in the same layer and the intersecting microchannels 12 in the upper and lower layers, causing strong fluid turbulence. When the cooling medium flows into the intersection region 13 of the intersecting microchannels 12 in the same layer, the cooling medium will flow from one microchannel of the intersecting microchannels 12 into another microchannel of the intersecting microchannels 12. When the cooling medium flows into the intersection region 13 of the intersecting microchannels 12 in the upper and lower layers, the cooling medium will flow from one intersecting microchannel 12 in one layer of the channel heat sink 10 into another intersecting microchannel 12 in the other layer of the microchannel heat sink 10, causing fluid turbulence of the cooling medium inside the radiator, destroying the thermal boundary layer, promoting the mixing of hot and cold fluids inside the microchannel heat sink 10, and improving the heat transfer efficiency of the radiator.

[0043] Finally, it flows out of the microchannel zone 6 from the heat sink outlet 14 and merges into the confluence zone 7, then flows out along the cooling medium outlet 4.

[0044] In the embodiments of the present invention, the heat sink described above is fastened to the electronic device by a mounting bracket.

[0045] This invention increases the convective heat transfer area by adjusting the number and structural dimensions of the two intersecting microchannels 12 in the upper and lower channels of the heat sink 10, thereby meeting different heat dissipation requirements. Simultaneously, it enhances the disturbance of the cooling medium inside the microchannel heat sink, promoting the mixing of the upper low-temperature cooling medium and the lower high-temperature cooling medium, improving the heat transfer uniformity of the heat sink, and strengthening heat transfer to ensure uniform heat dissipation throughout the entire heat sink, preventing the formation of localized high-temperature hotspots. This invention is mainly used for heat dissipation of integrated circuit chips, reducing the temperature of integrated chips, and improving the stability and lifespan of microelectronic chips.

[0046] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A microchannel heat sink, characterized in that, include: A silicon substrate (1) and a packaging plate (2) are bonded together to form a sealed space. The sealed space is divided into a pin rib area (5), a microchannel area (6) and a confluence area (7) along the diameter of the silicon substrate (1). A cooling medium inlet (3) is provided at the center of the encapsulation plate (2), and a cooling medium outlet (4) connecting the confluence zone (7) is provided on the outer circumference of the sealed space. The needle rib area (5) includes oblique triangular prism needle ribs (5.2) arranged in a ring, and cylindrical needle ribs (5.1) located inside the ring. The microchannel area (6) is equipped with a microchannel heat sink (10). The microchannel heat sink (10) adopts a double-layer microchannel structure. Each layer is composed of petal-shaped microchannel structure units (11) arranged in a ring array. The petal-shaped microchannel structure unit (11) is composed of two intersecting microchannels, and there are at least two intersecting areas. The inlets of the two microchannels are connected to the needle rib area (5), and the outlets are connected to the confluence area (7). The upper and lower petal-shaped microchannel structural units (11) are staggered and partially overlapped along the circumferential direction, and the microchannels at the overlap are interconnected in the vertical direction.

2. The microchannel heat sink according to claim 1, characterized in that, The cylindrical needle ribs (5.1) are arranged in a circular array along the center of the silicon substrate (1) to form a cylindrical needle rib region, and the oblique triangular prism needle ribs (5.2) are arranged in a circular array along the edge of the cylindrical needle rib region to form an oblique triangular prism needle rib region.

3. The microchannel heat sink according to claim 1, characterized in that, The radius of the silicon substrate (1) is 5-12 mm.

4. The microchannel heat sink according to claim 1, characterized in that, The radius of the cylindrical needle rib (5.1) is 0.03-0.08 mm, the height of the cylindrical needle rib (5.1) is 0.3-0.8 mm, and the number of layers of the cylindrical needle rib (5.1) is 4-7.

5. The microchannel heat sink according to claim 1, characterized in that, The bottom side length of the oblique triangular prism needle rib (5.2) is 0.12-0.18 mm, the height of the oblique triangular prism needle rib (5.2) is 0.3-0.8 mm, the number of layers of the oblique triangular prism needle rib (5.2) is 1-5, and the distance between each layer is 0.15-0.5 mm.

6. The microchannel heat sink according to claim 1, characterized in that, The height of each layer of the microchannel heat sink (10) is 0.25 mm, and the width of the microchannel (12) is 0.1-0.35 mm.

7. The microchannel heat sink according to claim 1, characterized in that, Heat sink outlets (14) are staggered on the outer wall of the microchannel heat sink (10).

8. The microchannel heat sink according to claim 1, characterized in that, The microchannel region (6) surrounds the needle rib region (5), and the confluence region (7) surrounds the microchannel region (6).

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