Chip microfluid cooling device and cooling method based on liquid metal electric actuation

Abstract

The invention discloses a chip microfluid cooling device based on liquid metal electric actuation and a cooling method. The chip microfluid cooling device comprises a first substrate and a second substrate, a concave part is formed on the first substrate; a cooling working medium is contained in the concave part; the second substrate is detachably assembled with the first substrate and covers the opening of the concave part; at least one liquid drop electrode combination immersed in the cooling working medium is arranged at the bottom of the sunken part; the liquid drop electrode combination comprises a metal liquid drop and at least one pair of driving electrodes, and the driving electrodes are used for being applied with different alternating current signals so that different potential distributions can be formed on the interface between the metal liquid drop and the cooling working medium. The device provided by the embodiment of the invention is simple in structure and convenient to integrate on a device layer, and the integration level and the heat dissipation capability of the electronic device are greatly improved.

Description

Technical Field

[0001] The present application relates to the field of chip technology, and in particular to a chip microfluidic cooling device and cooling method based on liquid metal electrical actuation. Background Art

[0002] As electronic devices tend to be integrated and miniaturized, their heat generation per unit area has increased dramatically, and more efficient thermal management technologies are urgently needed. Among the related technologies, active liquid cooling technology has broad development prospects due to its advantages such as strong heat dissipation capacity, good temperature uniformity, long heat transport distance, and flexible adjustment. Among them, the micro pump is the core component of the active liquid cooling system. Its performance determines the heat dissipation capacity and reliability of the entire liquid cooling system, and its size also determines the integration performance of the entire heat dissipation system. In the related technologies, the microchannel heat dissipation technology, jet or evaporative cooling technology used in electronic devices mostly use traditional mechanical pumps. For electronic devices, their relatively large size also makes it difficult to integrate at the device level, resulting in significant limitations on the integration of electronic devices and the heat dissipation capacity of electronic devices.

[0003] The above statements are only used to provide background information related to the present application and do not necessarily constitute prior art. Summary of the Invention

[0004] The purpose of this application is to provide a chip microfluidic cooling device and cooling method based on liquid metal electro-actuation, aiming to at least partially solve the problem in the related art that the integration of electronic devices and the heat dissipation capacity of electronic devices are greatly limited due to the use of mechanical pumps. In order to have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a general review, nor is it intended to identify key / important components or to describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0005] According to one aspect of an embodiment of the present application, a chip microfluidic cooling device based on liquid metal electro-actuation is provided, comprising a first substrate and a second substrate; a recess is formed on the first substrate; a cooling medium is contained in the recess; the second substrate is detachably assembled with the first substrate and covers the opening of the recess; at least one droplet electrode assembly immersed in the cooling medium is provided at the bottom of the recess; the droplet electrode assembly comprises a metal droplet and at least one pair of driving electrodes, the driving electrodes being used to be applied with different AC signals so as to form different potential distributions on the interface between the metal droplet and the cooling medium. Different potential distributions can guide the metal droplet to undergo interfacial convection. Furthermore, the cooling medium is caused to flow by viscous shear force, thereby absorbing heat from the on-chip heat source and dissipating it outward through the second substrate and the first substrate, resulting in high heat dissipation efficiency.

[0006] In some embodiments of the present application, the recessed portion is an annular groove, and the cooling medium is contained in the annular groove. The annular groove forms an annular channel, and the cooling medium in the annular groove can circulate in the annular channel. This is suitable for scenarios where there is a cold end on the chip, so that the high-temperature cooling medium is transported to the cold end, and the cooling medium cooled by the cold end is then transported to the on-chip heat source, thereby achieving the effect of cooling the on-chip heat source. When the cooling medium in the annular groove flows, it can evenly distribute the heat from the on-chip heat source to the entire cooling medium, and dissipate the heat outward through the second substrate and the first substrate, further improving the heat dissipation efficiency.

[0007] In some embodiments of the present application, the bottom of the recessed portion is provided with a plurality of droplet electrode assemblies arranged in an array and immersed in the cooling medium. The arrayed arrangement of the liquid metal array composed of the plurality of droplet electrode assemblies within the cooling medium enables dynamic and flexible control of the global temperature through flexible flow field encoding.

[0008] In some embodiments of the present application, the material of the cooling medium includes sodium chloride solution, potassium chloride solution or sodium hydroxide solution.

[0009] In some embodiments of the present application, the material of the driving electrode includes copper, platinum, silver, titanium or gold.

[0010] In some embodiments of the present application, the material of the metal droplet includes gallium, gallium-indium alloy, or gallium-indium-tin alloy.

[0011] In some embodiments of the present application, materials of the second substrate and the first substrate include silicon, glass, or polymer.

[0012] According to another aspect of the embodiments of the present application, a chip microfluidic cooling method based on liquid metal electro-actuation is provided, which is applied to the device described in any embodiment of the present application; the method comprises:

[0013] The chip to be cooled is arranged on the first surface of the second substrate; the first surface is a side surface opposite to the first substrate;

[0014] Different AC signals are applied to the drive electrodes to create different potential distributions at the interface between the metal droplets and the coolant, guiding the metal droplets to undergo interfacial convection and causing the coolant to flow. This flow of the coolant dissipates heat from the on-chip heat source through the first and second substrates, improving heat dissipation efficiency.

[0015] In some embodiments of the present application, the recessed portion is an annular groove, and the cooling medium is contained in the annular groove;

[0016] The step of causing the cooling medium to flow comprises:

[0017] The cooling medium is made to flow in the annular groove along an annular direction.

[0018] One aspect of the technical solution provided by the embodiments of the present application may have the following beneficial effects:

[0019] The chip microfluidic cooling device based on liquid metal electro-actuation provided in the embodiment of the present application includes a first substrate and a second substrate; a recess is formed on the first substrate; a cooling medium is contained in the recess; the second substrate is detachably assembled with the first substrate and covers the opening of the recess; at least one droplet electrode combination immersed in the cooling medium is provided at the bottom of the recess; the droplet electrode combination includes a metal droplet and at least one pair of driving electrodes, and the driving electrodes are used to be applied with different AC signals to form different potential distributions on the interface between the metal droplet and the cooling medium. The device provided in the embodiment of the present application has a simple structure and is easy to integrate at the device level, which greatly improves the integration level of electronic devices and the heat dissipation capacity of electronic devices.

[0020] The above description is only an overview of the technical solutions of the embodiments of the present application. In order to more clearly understand the technical means of the embodiments of the present application, they can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic structural diagram of a chip microfluidic cooling device based on liquid metal electro-actuation according to an embodiment of the present application is shown.

[0023] Figure 2 A schematic structural diagram of a chip microfluidic cooling device based on liquid metal electro-actuation according to an embodiment of the present application is shown.

[0024] Figure 3 A schematic structural diagram of a chip microfluidic cooling device based on liquid metal electro-actuation according to an embodiment of the present application is shown.

[0025] Figure 4 A schematic structural diagram of a chip microfluidic cooling device based on liquid metal electro-actuation according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of this application more clearly understood, this application is further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0028] In response to the problem that the pumps used in electronic devices in the related art are mostly mechanical pumps, which are large in size and difficult to integrate at the device level, resulting in significant limitations on the device integration and device heat dissipation capacity, the embodiment of the present application provides a chip microfluidic cooling device based on liquid metal electro-actuation, including a first substrate and a second substrate, a recessed portion formed on the first substrate, a cooling medium contained in the recessed portion, and a second substrate detachably assembled with the first substrate and covering the opening of the recessed portion. At least one droplet electrode assembly immersed in the cooling medium is provided at the bottom of the recessed portion, the droplet electrode assembly includes a metal droplet and at least one pair of drive electrodes, and the drive electrodes are used to be applied with different AC signals to form different potential distributions on the interface between the metal droplet and the cooling medium, thereby guiding the metal droplet to undergo interfacial convection, causing the cooling medium to flow, and dissipating the heat of the on-chip heat source through the first substrate and the second substrate, thereby improving the heat dissipation efficiency. In addition, the chip microfluidic cooling device provided in the embodiment of the present application has a simple structure and is easy to integrate at the device level, greatly improving the integration and heat dissipation capacity of the electronic device.

[0029] Liquid metal continuous electrowetting technology is a highly efficient fluid actuation technology. It only requires applying an electric field to the electrolyte solution in which the liquid metal is located, and convection will occur at the liquid metal interface to pump the surrounding fluid. Therefore, continuous electrowetting actuation of metal droplets is a potential active liquid cooling. The embodiment of the present application realizes a miniaturized, highly integrated, and flexibly controllable chip active liquid cooling technology through the fluid pumping effect of liquid metal electro-actuation. The continuous electrowetting actuation of metal droplets under high-frequency electrical signals is used. On the one hand, the heat exchange between the heat source and the cooling medium is enhanced through convection at the liquid metal interface. On the other hand, the high-frequency AC signal suppresses the generation of electrolytic bubbles, so that it can be stably and reliably integrated inside the microsystem. The chip microfluidic cooling device based on liquid metal electro-actuation provided in the embodiment of the present application forms a cooling medium circulation through continuous electrowetting of liquid metal, thereby realizing the miniaturization and integration of the liquid cooling drive system.

[0030] The following describes a chip microfluidic cooling device and cooling method based on liquid metal electro-actuation according to an embodiment of the present application in conjunction with the accompanying drawings.

[0031] refer to Figure 1As shown, an embodiment of the present application provides a chip microfluidic cooling device based on liquid metal electro-actuation, comprising a first substrate 2 and a second substrate 4; a recess is formed on the first substrate 2; a cooling medium 3 is contained in the recess; the second substrate 4 is detachably assembled with the first substrate 2 and covers the opening of the recess; at least one droplet electrode combination immersed in the cooling medium 3 is provided at the bottom of the recess; the droplet electrode combination comprises a metal droplet 6 and at least one pair of driving electrodes 5, the driving electrode 5 is used to be applied with different AC signals to form different potential distributions on the interface between the metal droplet 6 and the cooling medium 3.

[0032] Figure 1 The shape of the metal droplet 6 includes but is not limited to a hemispherical shape. The driving electrode 5 can be located on the bottom surface of the recessed portion of the second substrate 4 and embedded in the second substrate 4 .

[0033] When using the chip microfluidic cooling device based on liquid metal electro-actuation, the on-chip heat source 1 can be set on the first surface of the second substrate 4, the first surface being the side surface opposite to the first substrate 2, and the first surface can contact the cooling medium 3. Figure 2 The edge of the first substrate 2 Figure 1 The view in the direction indicated by arrow A, refer to Figure 2 As shown, the at least one pair of driving electrodes 5 is arranged around the metal droplet 6, and different AC signals can be applied to each driving electrode 5 to form different potential distributions on the interface between the metal droplet 6 and the cooling medium 3, thereby guiding the metal droplet 4 to undergo interfacial convection. Furthermore, the cooling medium 3 is caused to flow by viscous shear force, and the flow direction includes but is not limited to Figure 2 The heat source 1 on the chip is absorbed in the direction indicated by the arrow shown in the figure, and the heat is dissipated outward through the second substrate 2 and the first substrate 4. The heat dissipation efficiency is high and the heat source 1 on the chip can be effectively dissipated. The first surface of the second substrate 4 can release the cooling medium 3, thereby further improving the heat dissipation efficiency.

[0034] Figure 2 Two driving electrodes 5 are correspondingly arranged around the metal droplet 6.

[0035] Different from the technical solution of using mechanical pumps to achieve cooling in related technologies, this embodiment uses the fluid pumping effect of liquid metal electro-actuation to achieve a chip active liquid cooling technology with miniaturized cooling device, high integration and flexible control.

[0036] Figure 3 In another embodiment, the first substrate 2 is Figure 1 The view in the direction indicated by arrow A, refer to Figure 3As shown, in some embodiments, the recessed portion is an annular groove, and the cooling medium 3 is contained in the annular groove. The annular groove forms an annular channel. The cooling medium 3 in the annular groove can circulate in the annular channel. This is suitable for the scenario where there is a cold end on the chip, so that the high-temperature cooling medium 3 is transported to the cold end, and the cooling medium 3 cooled by the cold end is then transported to the on-chip heat source 1, thereby achieving the effect of cooling the on-chip heat source 1. Figure 3 The layout shown can form a global circulation of the cooling medium 3, and the circulation direction is not limited to Figure 3 In the direction indicated by the middle arrow, the heat at the on-chip heat source 1 can be evenly distributed to the entire cooling medium 3, and the heat is dissipated outward through the second substrate 2 and the first substrate 4, further improving the heat dissipation efficiency. Figure 2 Two driving electrodes 5 are correspondingly arranged around the metal droplet 6.

[0037] Figure 4 In another embodiment, the first substrate 2 is Figure 1 The view in the direction indicated by arrow A, refer to Figure 4 As shown, in some embodiments, a plurality of droplet electrode assemblies arranged in an array and immersed in the cooling medium 3 are provided at the bottom of the recessed portion. Figure 4 The layout in is a multiple metal droplet convection heat dissipation layout. Figure 4 Figure 3 shows four droplet electrode assemblies, each comprising metal droplets 61, 62, 63, and 64. Four drive electrodes 51 are arranged around metal droplet 61, four drive electrodes 52 are arranged around metal droplet 62, four drive electrodes 53 are arranged around metal droplet 63, and four drive electrodes 54 are arranged around metal droplet 64. The arrayed arrangement of the four metal droplets enables the formation of more complex flow patterns within the domain of the cooling medium 3, as well as the switching of flow patterns. This facilitates dynamic and flexible control of temperature distribution.

[0038] Each metal droplet and the driving electrode are along Figure 1 The shape in the direction indicated by arrow A includes but is not limited to a circle. The number of droplet electrode combinations can be selected according to the needs of the actual application, and the number of driving electrodes corresponding to the metal droplet in each droplet electrode combination can be selected according to the needs of the actual application.

[0039] Through the array layout of the liquid metal array composed of the aforementioned multiple droplet electrode combinations in the cooling medium, dynamic and flexible regulation of the global temperature is achieved through flexible flow field coding.

[0040] In some embodiments, the material of the cooling medium 3 includes, but is not limited to, sodium chloride solution, potassium chloride solution, or sodium hydroxide solution. Solutions such as sodium chloride and potassium chloride have high ion concentrations, enabling rapid response to electric field signals and reducing flow field response delay. Sodium hydroxide solution provides strong ion migration capabilities. Sodium chloride and potassium chloride solutions are low-cost and suitable for enclosed spaces; sodium hydroxide solution is suitable for high-temperature or high-power scenarios. The electrolyte material can be selected based on the specific application scenario.

[0041] In some embodiments, the material of the drive electrode 5 includes, but is not limited to, copper, platinum, silver, titanium, or gold. Copper and other metals offer excellent conductivity and low cost, making them suitable for large-scale production. Precious metals such as silver and gold offer excellent conductivity and are suitable for applications requiring stringent performance requirements. Platinum and titanium offer strong corrosion resistance in electrolyte environments, extending the life of the electrode. The material of the drive electrode can be selected based on the specific application scenario.

[0042] The metal droplets 6 are droplets formed of liquid metal. In some embodiments, the material of the metal droplets 6 includes, but is not limited to, gallium, gallium-indium alloy, or gallium-indium-tin alloy. Gallium-indium-tin alloy and gallium-indium alloy have low melting points and are liquid at room temperature, making them easy to form controllable droplets through electric fields or geometric constraints. Gallium has excellent electrical and thermal conductivity, and can efficiently respond to electric field signals and transfer heat. An oxide layer easily forms on the surface of liquid metal, and the surface tension gradient can be dynamically adjusted through the electrowetting effect to drive the movement of the droplets. In specific applications, the material of the liquid metal droplets can be selected according to the actual application scenario.

[0043] In some embodiments, the materials of the second substrate 4 and the first substrate 2 include silicon, glass, or polymers. Silicon has high thermal conductivity, effectively dissipating heat and improving the reliability of electronic devices. It is also chemically inert and impermeable, maintaining stable performance in harsh environments. Glass is resistant to acid and alkali corrosion and has strong long-term stability. Polymers have low density and high strength, reducing device weight. They are also resistant to acid, alkali, and solvent corrosion, making them suitable for harsh environments. They also have low processing temperatures, simple processes, and low costs.

[0044] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0045] Another embodiment of the present application provides a chip microfluidic cooling method based on liquid metal electro-actuation, which is applied to the chip microfluidic cooling device based on liquid metal electro-actuation described in any embodiment of the present application; the chip microfluidic cooling method based on liquid metal electro-actuation may include:

[0046] The chip to be cooled is arranged on the first surface of the second substrate; the first surface is a side surface opposite to the first substrate;

[0047] Different AC signals are applied to the driving electrodes to form different potential distributions on the interface between the metal droplets and the cooling medium, guiding the metal droplets to undergo interfacial convection and causing the cooling medium to flow.

[0048] The cooling medium flows and dissipates the heat of the on-chip heat source outward through the first substrate and the second substrate, thereby improving the heat dissipation efficiency.

[0049] In some embodiments, the recessed portion is an annular groove, and the cooling medium is contained in the annular groove;

[0050] Causing the cooling medium to flow includes: causing the cooling medium to flow in an annular direction within the annular groove. The annular groove forms an annular channel, and the cooling medium in the annular groove circulates within the annular channel. The circulating flow is suitable for scenarios where there is a cold end on the chip, thereby transporting the high-temperature cooling medium to the cold end, and the cooling medium cooled by the cold end is then transported to the on-chip heat source, achieving the effect of cooling the on-chip heat source. The cooling medium forms a global circulation, thereby evenly dissipating the heat from the on-chip heat source throughout the cooling medium, and dissipating the heat outward through the second substrate and the first substrate.

[0051] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced with each other and will not be repeated herein for the sake of brevity.

[0052] It should be noted that the above embodiments merely represent implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and such modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A chip microfluidic cooling device based on liquid metal electro-actuation, characterized in that: It includes a first substrate and a second substrate; a recess is formed on the first substrate; a cooling medium is contained in the recess; the second substrate is detachably assembled with the first substrate and covers the opening of the recess; at least one droplet electrode combination immersed in the cooling medium is provided at the bottom of the recess; the droplet electrode combination includes a metal droplet and at least one pair of driving electrodes, and the driving electrodes are used to be applied with different AC signals to form different potential distributions on the interface between the metal droplet and the cooling medium.

2. The device according to claim 1, characterized in that The recessed portion is an annular groove, and the cooling medium is contained in the annular groove.

3. The device according to claim 1, characterized in that A plurality of liquid droplet electrode assemblies arranged in an array and immersed in the cooling medium are provided at the bottom of the recessed portion.

4. The device according to any one of claims 1 to 3, characterized in that The material of the cooling medium includes sodium chloride solution, potassium chloride solution or sodium hydroxide solution.

5. The device according to any one of claims 1 to 3, characterized in that The driving electrode is made of copper, platinum, silver, titanium or gold.

6. The device according to any one of claims 1 to 3, characterized in that The material of the metal droplets includes gallium, gallium-indium alloy or gallium-indium-tin alloy.

7. The device according to any one of claims 1 to 3, characterized in that The second substrate and the first substrate are made of silicon, glass or polymer.

8. A chip microfluidic cooling method based on liquid metal electro-actuation, characterized in that: Applied to the device according to any one of claims 1 to 7; the method comprising: The chip to be cooled is arranged on the first surface of the second substrate; the first surface is a side surface opposite to the first substrate; Different AC signals are applied to the driving electrodes to form different potential distributions on the interfaces between the metal droplets and the cooling medium, thereby guiding the metal droplets to generate interfacial convection and causing the cooling medium to flow.

9. The method according to claim 8, characterized in that The recessed portion is an annular groove, and the cooling medium is contained in the annular groove; The step of causing the cooling medium to flow comprises: The cooling medium is made to flow in the annular groove along an annular direction.

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