Diamond copper-based heat dissipation plate, chip heat dissipation device, preparation method and application

Abstract

The invention discloses a diamond copper-based heat dissipation plate, a chip heat dissipation device, a preparation method and application, and relates to the technical field of microelectronic heat dissipation. The method comprises the following steps: taking pure copper or a stainless steel plate as a cathode, taking pure copper as an anode, taking a mixed solution of sulfuric acid and copper sulfate as electrolyte, and taking acrylic resin as an electrolytic bath; diamond particles are uniformly dispersed in the electrolyte, and a cathode is placed at the bottom of an electrolytic bath; the preparation method comprises the following steps: carrying out electro-deposition on a cathode by adopting an electro-deposition method, cleaning a deposition sample on the cathode by adopting pure water after the deposition is finished, then carrying out passivation operation, cleaning the deposition sample again by adopting pure water after the passivation is finished, and finally drying in vacuum, so as to obtain the diamond copper block on the cathode. Compared with other high-temperature methods such as a vacuum hot pressing method and a spark plasma sintering method, the pulse current technology adopted by the invention can be carried out in one step at the environment temperature without pressure, so that the process is simple and has cost benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of microelectronic heat dissipation, and in particular to a diamond copper-based heat dissipation plate, a chip heat dissipation device, a preparation method and an application thereof. Background Art

[0002] In recent years, with the rapid development of electronic components, the characteristic size of transistors has been continuously reduced, and the number of transistors integrated on the chip has also increased, resulting in the continuous increase in the power of integrated circuit chips and the generation of a large amount of heat. The impact of high temperature on chip performance and life is becoming increasingly significant. Studies have shown that if the large amount of heat energy generated by the chip during operation is not promptly discharged, the life of the device will be reduced, and even worse, the device will fail. Therefore, the heat dissipation problem has become a key factor restricting the performance and life of integrated circuit chips. Therefore, the improvement of heat dissipation technology is crucial to protecting the safe and stable operation of the chip. The heat dissipation methods currently on the market mainly include active heat dissipation and passive heat dissipation. However, traditional passive heat dissipation methods such as heat dissipation fins have limited heat dissipation capacity and cannot effectively solve the problem of high temperature of the chip. Although the active heat dissipation method can reduce the chip temperature through the flow of coolant, the materials and structures used still need to be improved. Therefore, a heat dissipation method that can both improve the heat dissipation effect and simplify the system design is needed. Summary of the invention

[0003] In view of the deficiencies in the above background technology, the present invention provides a diamond copper-based heat sink, a chip heat sink, and a preparation method and application. In order to solve the above problems, the purpose of the present invention is to provide a heat dissipation system combining an active heat dissipation solution with a passive heat dissipation solution, which can improve the heat dissipation performance of high-power chips, increase the heat dissipation limit, and extend the service life of high-power chips.

[0004] The first object of the present invention is to provide a method for preparing a diamond copper-based block, comprising the following steps: Use pure copper or stainless steel plate as cathode, pure copper as anode, a mixed solution of sulfuric acid and copper sulfate as electrolyte, and propylene resin as electrolytic cell; The diamond particles are evenly dispersed in the electrolyte, and the cathode is placed at the bottom of the electrolytic cell; the electrodeposition method is used to carry out electrodeposition on the cathode. After the deposition is completed, the deposited sample on the cathode is cleaned with pure water, and then passivation operation is carried out. After the passivation is completed, it is cleaned again with pure water, and finally dried under vacuum, so that a diamond copper block is obtained on the cathode.

[0005] Preferably, during the electrodeposition, a pulse current technique is used, and the electrodeposition is performed by setting pulse current parameters; wherein the pulse current parameters include pulse period, pulse width, and pulse current density.

[0006] Preferably, the molar ratio of copper sulfate to sulfuric acid in the mixed solution is 1:10-20.

[0007] A second object of the present invention is to provide a diamond copper-based block.

[0008] The third object of the present invention is to provide a diamond copper heat sink, which uses a laser or a water jet to cut a diamond copper base block into diamond copper plates of uniform size and specifications, and serves as a diamond copper heat sink in a heat dissipation system.

[0009] A fourth object of the present invention is to provide an application of a diamond copper heat sink in chip heat dissipation.

[0010] A fifth object of the present invention is to provide a chip heat dissipation device, comprising a diamond copper fin disposed on the top of the chip, and a microchannel heat dissipation layer disposed on the bottom of the chip; The microchannel heat dissipation layer is a diamond copper heat conducting plate processed from a diamond copper base block, and a serpentine microchannel is opened inside the plate, and a circulating coolant is passed through the microchannel; The diamond copper fin is made by processing a diamond copper heat sink.

[0011] Preferably, one end of the serpentine microchannel is provided with a through hole I for introducing the coolant, and the other end is provided with a through hole II for draining the coolant.

[0012] Preferably, the coolant is water or liquid metal.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a diamond copper-based heat sink, a chip heat sink, a preparation method and an application. The present invention adopts pulse current technology to perform an electrodeposition method to prepare diamond copper material. Compared with other high-temperature methods such as vacuum hot pressing method and spark plasma sintering method, the electrodeposition method is carried out in one step at ambient temperature and is pressure-free, which makes the process simple and cost-effective. The use of pulse power is conducive to the formation of diamond copper seeds, improves the uniformity of diamond copper growth, reduces hydrogen production and electrolyte loss, and improves the efficiency and energy utilization of electrodeposition. The present invention adopts diamond copper material as the main material of the heat dissipation system. Diamond copper has an extremely high melting point and thermal stability, can work stably for a long time in a high temperature environment, and will not be burned or deformed due to high temperature; has excellent corrosion resistance, can resist the erosion of common corrosive media, and prolong the service life of the heat dissipation system; has high strength and hardness, is not easy to deform or damage, and can maintain stable performance in harsh working environments; The active and passive integrated heat dissipation solution adopted by the present invention can give full play to the advantages of the two heat dissipation methods, improve the overall heat dissipation effect, and improve the overall heat dissipation efficiency while maintaining stable temperature control. It can more accurately control the temperature of the heat dissipation system to avoid overheating or overcooling, and protect the normal operation of system components; The active and passive integrated heat dissipation scheme adopted by the present invention can be flexibly adjusted according to actual conditions, adapting to the heat dissipation requirements under different workloads and environmental conditions, and can improve the stability of the heat dissipation system. When the load is high, the working intensity of active heat dissipation can be increased to improve the heat dissipation effect; when the load is low, the working intensity of active heat dissipation can be reduced, relying on passive heat dissipation to dissipate heat, so as to save energy and reduce noise; the simple reliability of the passive heat dissipation method can increase the stability of the system heat dissipation, reduce the occurrence of failures, and can still perform heat dissipation work in extreme cases. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the process of preparing diamond copper by electrodeposition method in the present invention; Figure 2 It is a front view of the chip heat dissipation device of the present invention; Figure 3 This is a front view of the diamond copper fin of the present invention; Figure 4 is a top view of the microchannel heat dissipation layer of the present invention; Figure 5 This is a heat dissipation effect diagram of the diamond copper heat dissipation plate of the present invention; Figure 6 This is a diagram showing the passive heat dissipation effect of the diamond copper fins in the present invention; Figure 7 This is a heat dissipation effect diagram of the chip heat dissipation device in the present invention. DETAILED DESCRIPTION

[0015] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0016] The purpose of the present invention is to provide a heat dissipation system combining an active heat dissipation solution with a passive heat dissipation solution, which can improve the heat dissipation performance of a high-power chip, increase the heat dissipation limit, and extend the service life of the high-power chip.

[0017] In order to achieve the above object, the present invention provides a first aspect of a method for preparing a diamond copper-based block, comprising the following steps: Use pure copper or stainless steel plate as cathode, pure copper as anode, a mixed solution of sulfuric acid and copper sulfate as electrolyte, and propylene resin as electrolytic cell; The diamond particles are evenly dispersed in the electrolyte, and the cathode is placed at the bottom of the electrolytic cell; the electrodeposition method is used to carry out electrodeposition on the cathode. After the deposition is completed, the deposited sample on the cathode is cleaned with pure water, and then passivation operation is carried out. After the passivation is completed, it is cleaned again with pure water, and finally dried under vacuum, so that a diamond copper block is obtained on the cathode.

[0018] During the electro-deposition, pulse current technology is used, and the electro-deposition is performed by setting pulse current parameters; wherein the pulse current parameters include pulse period, pulse width, and pulse current density.

[0019] The molar ratio of copper sulfate to sulfuric acid in the mixed solution is 1:10~20.

[0020] In one embodiment, see Figure 1 As shown, diamond copper material is prepared by electrodeposition using a pulse power supply. Use pure copper or stainless steel plate as cathode 18; pure copper as anode 17; a mixed solution of sulfuric acid and copper sulfate as electrolyte 14; propylene resin as electrolytic cell 15; place cathode 18 at the bottom of the electrolytic cell; Diamond particles are added to the copper plating solution and dispersed evenly using a stirring rod so that they settle undisturbed on the cathode without any aggregation; The cathode 18 and the anode 17 are connected to the pulse power supply 11 through the wire 13, and the pulse current parameters are set, including the pulse period, pulse width, and pulse current density. The switch 12 of the pulse power supply 11 is turned on, and the diamond copper material 16 is prepared by electrodeposition using the pulse current technology; The thickness of the cathode plate is set to be 200-400 μm, the length is 20-30 cm, and the width is 10-15 cm. The average particle size of the selected diamond particles is 5-10 μm.

[0021] The prepared diamond copper sample is cleaned with pure water, then passivated, cleaned again with pure water after passivation, and finally dried under vacuum to obtain a diamond copper block; Weigh the sample to determine the composition and thermal conductivity of the prepared diamond copper; The diamond copper block prepared by the above operation is cut into diamond copper plates with uniform size and specifications by laser or water jet, and used as diamond copper heat sink plates in the heat dissipation system.

[0022] A second aspect of the present invention provides a diamond copper-based block.

[0023] A third aspect of the present invention provides a diamond copper heat sink, which uses a laser or a water jet to cut a diamond copper-based block into diamond copper plates of uniform size and specifications, and serves as a diamond copper heat sink in a heat dissipation system.

[0024] A fourth aspect of the present invention provides an application of a diamond copper heat sink in chip heat dissipation.

[0025] A fifth aspect of the present invention provides a chip heat dissipation device, comprising a diamond copper fin disposed on the top of the chip, and a microchannel heat dissipation layer disposed on the bottom of the chip; The microchannel heat dissipation layer is a diamond copper heat conducting plate processed from a diamond copper base block, and a serpentine microchannel is opened inside the plate, and a circulating coolant is passed through the microchannel; The diamond copper fin is made by processing a diamond copper heat sink.

[0026] One end of the serpentine microchannel is provided with a through hole I for introducing the coolant, and the other end is provided with a through hole II for leading out the coolant.

[0027] The coolant is water or liquid metal.

[0028] In one embodiment, see Figures 2~4 As shown, a diamond copper-based active and passive integrated high-efficiency chip heat dissipation solution is used. Diamond copper is prepared by electrodeposition. The top of the high-power chip is designed as a diamond copper fin as a passive heat dissipation part, and the bottom of the high-power chip is designed as a diamond copper-based microchannel heat dissipation layer as an active heat dissipation part. These two parts are tightly bonded to the high-power chip. Relying on the excellent thermal conductivity of the diamond copper material, the heat generated by the high-power chip will be introduced into the heat dissipation system from the top and bottom respectively. A specific chip heat dissipation device includes: The prepared diamond copper heat sink is cut into corresponding diamond copper fins 1 according to the package size of the high-power chip 8, and bonded to the top of the high-power chip to form a whole, so that the heat of the chip can be conducted from above. Both sides of the high-power chip are connected to the electrodes 9 through wires 10.

[0029] The diamond copper fin 1 is composed of a self-supporting diamond copper film, the top surface of which is processed to form a series of convex fins, which are arranged in the front-to-back direction and have grooves formed between adjacent fins. Multiple fins are evenly distributed on the entire structure to form a continuous toothed structure.

[0030] Among them, the length, width and height of the self-supporting diamond copper film are x × y × h The shape of the fin is a cuboid, the depth is z, and the spacing between adjacent fins is m.

[0031] A layer of diamond copper heat conducting plate 4 is bonded under the chip to conduct heat away from the bottom.

[0032] A microchannel with diamond copper as a substrate is designed in the diamond copper heat conducting plate 4. A serpentine microchannel 6 is etched in the microchannel heat dissipation layer to form a microchannel heat dissipation array.

[0033] The cooling liquid in the microchannel 6 is selected to be liquid with good thermal conductivity such as liquid metal mercury or water.

[0034] One end of the microchannel 6 is etched with a microthrough hole 3 for introducing coolant and a microthrough hole 7 for discharging coolant along the edge 5 of the diamond copper heat conducting plate. The two microthrough holes are arranged along the diagonal direction of the top view of the microchannel heat dissipation layer.

[0035] The micro pump 19 is designed to connect the through hole 3. When the pump is started, it can drive the coolant in the micro channel 6 to flow quickly to remove the heat transferred to the heat dissipation substrate.

[0036] The length, width and height of the finished diamond copper heat conducting plate are a × b × c , where the maximum height difference between the top and the middle part of the diamond copper heat conducting plate is s, and the cross-section of the microfluidic channel aperture after bonding is t×t; The diamond copper heat conducting plate is also called a diamond copper micro-channel heat dissipation plate.

[0037] The present invention can also design micro structures such as vortex generators inside the microchannel to assist in heat dissipation and improve heat dissipation efficiency.

[0038] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0039] Embodiment 1 Step 1: Use pure copper or stainless steel plate as cathode; pure copper as anode; a mixed solution of copper sulfate and sulfuric acid with a molar ratio of 1:10 as electrolyte; propylene resin as electrolytic cell; place the cathode at the bottom of the electrolytic cell; The cathode plate is a rectangular parallelepiped, and its specifications can be selected within a wide range. In this embodiment, the cathode plate is set to have a thickness of 400 μm, a length of 30 cm, and a width of 15 cm.

[0040] Step 2: Add diamond particles to the copper plating solution and disperse them evenly using a stirring rod so that they settle on the cathode undisturbed without any aggregation; The copper plating solution is the electrolyte described in step 1; In order to improve the thermal conductivity of the prepared diamond copper, the average particle size of the selected diamond particles is 5 μm. Too small a particle size will cause the diamond particles to agglomerate; too large a particle size will cause the diamond particles to settle, both of which are not conducive to the preparation of diamond copper.

[0041] Step 3: Set the pulse current parameters, set the pulse period to 1s, the pulse width to 0.1s, the positive pulse current density to 10mA / cm², and the negative pulse current density to 5mA / cm², turn on the pulse power supply, and use the pulse current technology to prepare diamond copper material by electrodeposition; Step 4: After the electroplating is completed, use pure water to wash for 2-3 minutes, passivate, and use pure water to wash again for 2-3 minutes, and then vacuum dry to obtain the prepared diamond copper product.

[0042] Step 5: Weigh the sample to determine the composition and thermal conductivity of the prepared diamond copper product.

[0043] Step 6: Cut the prepared diamond copper product into diamond copper plates of uniform specifications using a laser or a water jet; Step 7: Use laser or water jet to process diamond copper heat sink fins on the diamond copper plate; the length, width and height of the self-supporting diamond copper film are 30mm×30mm×2mm , the shape of the fin is cuboid, the depth is 8mm, and the spacing between adjacent fins is 2.625mm; Step 8: Bond the processed diamond copper heat sink fins to the top of the chip; Step 9: Use laser or water jet to process semi-cylindrical microchannels on two diamond copper plates, and etch two semi-circular through holes on both sides of the heat conducting plate to connect with the flow channel. The two through holes are named through hole I and through hole II; wherein, through hole I is a coolant inlet hole, and through hole II is a coolant outlet hole; Step 10: In the microchannel next to through hole I, weld a micro pump for controlling the flow of coolant; Step 11: Use a high temperature thermal stability bonding agent to bond two diamond copper plates to form the required closed microchannel; the length, width and height of the finished diamond copper microchannel heat sink are 40mm×40mm×3mm , where the maximum height difference between the top and the middle part of the diamond copper heat conducting plate is 1 mm, and the size of the microchannel hole after bonding is 1 mm × 1 mm; Step 12: Use a leak detector to detect whether the microchannel set in step 11 meets the air tightness requirements. If it does, go to step 13; otherwise, find the leak and seal it by welding or other methods, and retest the air tightness; Step 13: The workpiece is evacuated through through hole II, and then coolant is injected into the microchannel through through hole I, and then the vent hole is sealed; Step 14: Bond the high-power chip with the bonded passive heat dissipation part made in step 2 to the top of the outer wall of the diamond copper heat conductive plate, and use X-ray to detect the bonding holes to complete the production.

[0044] In order to further illustrate the diamond copper-based active and passive integrated high-efficiency chip heat dissipation provided by the present invention, the following description is provided in conjunction with the accompanying drawings.

[0045] The present invention uses comsol simulation software to model, sets the chip package size to 30mm×30mm×2mm, and presets its heat consumption rate to 5W. The results obtained through simulation calculation are as follows Figure 5 As shown, the maximum temperature of the chip core area can reach above 230°C at this time.

[0046] A diamond copper heat conducting plate is added to the chip. The diamond copper composite material used in the simulation has a diamond volume fraction of 35%. Its size is consistent with the chip package, that is, 30mm×30mm×2mm. Then 9 heat sink fins are added to the heat conducting plate. Their size is 30mm×8mm×1mm. They are evenly distributed to maximize the heat dissipation area. It is worth noting that in order to highlight the excellent heat dissipation performance of the diamond copper composite material, the simulation of the present invention does not apply an air cooling physical field to the heat sink fins, and completely relies on the passive heat dissipation ability of the heat sink fins. Through comsol simulation calculation, the results are as follows Figure 6 As shown in the figure, at this time, the maximum temperature of the chip center has been significantly reduced to below 105°C.

[0047] Furthermore, a larger diamond copper heat conducting plate is installed at the bottom of the chip. The simulation of the present invention sets its specifications to 40mm×40mm×3mm, and a microfluidic channel is designed inside it, with a channel cross section of 1mm×1mm square. In the comsol simulation environment, the fluid in the microfluidic channel is set to pure water, and the flow rate is set to 0.02m / s. The simulation results are as follows: Figure 7 As shown in the figure, the maximum temperature at the center of the chip has dropped sharply to 60°C. It is also worth mentioning that if the fluid flow rate is increased, the heat dissipation effect can be further increased and the temperature can continue to drop.

[0048] In summary, the present invention provides a diamond copper-based active and passive integrated high-efficiency chip heat dissipation. The diamond copper material is prepared by electrodeposition, and the heat dissipation system includes: diamond copper fins, diamond copper heat conduction plates and microchannel heat dissipation layers; the microchannel heat dissipation layer uses a liquid or liquid metal with good thermal conductivity as a coolant, and is provided with a micro pump, a coolant inlet through hole and a coolant outlet through hole. The innovative heat dissipation design adopted by the present invention includes two parts: a passive heat dissipation part and an active heat dissipation part. First, the heat generated by the integrated circuit chip is conducted to the diamond copper plate, and the heat above is extracted through the diamond copper fins to achieve passive heat dissipation. Secondly, the heat below is transferred to the microchannel through the diamond copper heat conduction plate. Driven by the micro pump device, the coolant flows in the microchannel to extract the heat and achieve active heat dissipation. The present invention relies on the high thermal conductivity of the diamond copper material and the active heat dissipation capability of the microchannel technology to improve the heat dissipation performance of the high-power chip, improve the heat dissipation limit, and extend the service life of the high-power chip.

[0049] The present invention describes preferred embodiments and their effects. However, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0050] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a diamond copper-based block, characterized in that: The following steps are involved: Use pure copper or stainless steel plate as cathode, pure copper as anode, a mixed solution of sulfuric acid and copper sulfate as electrolyte, and propylene resin as electrolytic cell; The diamond particles are evenly dispersed in the electrolyte, and the cathode is placed at the bottom of the electrolytic cell; the electrodeposition method is used to carry out electrodeposition on the cathode. After the deposition is completed, the deposited sample on the cathode is cleaned with pure water, and then passivation operation is carried out. After the passivation is completed, it is cleaned again with pure water, and finally dried under vacuum, so that a diamond copper block is obtained on the cathode.

2. The method for preparing a diamond copper-based block according to claim 1, characterized in that: During the electrodeposition, pulse current technology is used, and the electrodeposition is performed by setting pulse current parameters; wherein the pulse current parameters include pulse period, pulse width, and pulse current density.

3. The method for preparing a diamond copper-based block according to claim 1, characterized in that: The molar ratio of copper sulfate to sulfuric acid in the mixed solution is 1:10~20.

4. A diamond copper-based block obtained by the method according to any one of claims 1 to 3.

5. A diamond copper heat sink, characterized in that: The diamond copper-based block is cut into diamond copper plates of uniform size and specifications by laser or water jet, and used as diamond copper heat sinks in the heat dissipation system.

6. Use of the diamond copper heat sink as claimed in claim 5 in chip heat dissipation.

7. A chip heat dissipation device, characterized in that: It includes a diamond copper fin disposed on the top of the chip, and a microchannel heat dissipation layer disposed on the bottom of the chip; The microchannel heat dissipation layer is a diamond copper heat conducting plate processed from a diamond copper base block, and a serpentine microchannel is opened inside the plate, and a circulating coolant is passed through the microchannel; The diamond copper heat dissipation fins are processed from diamond copper heat conduction plates.

8. The chip heat dissipation device according to claim 7, characterized in that: One end of the serpentine microchannel is provided with a through hole I for introducing the coolant, and the other end is provided with a through hole II for leading out the coolant.

9. The chip heat dissipation device according to claim 7, characterized in that: The coolant is water or liquid metal.

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