A confined electrodeposition device, system and method based on two-phase temperature regulation

Abstract

The application relates to the technical field of micro-nano manufacturing and electrochemical additive manufacturing, and more particularly to a limited electrodeposition device, system and method based on two-phase temperature regulation. The device comprises a platform, a cathode substrate installed on the platform, a moving mechanism installed on the platform, a nozzle installed on the moving end of the moving mechanism, a heating assembly arranged on a liquid supply path of the nozzle and a cooling assembly installed on the platform; the heating assembly is used for heating working liquid to be higher than room temperature; a water flow channel is arranged in the nozzle; the surface of the cathode substrate is covered with a mask layer, and the cooling assembly is used for cooling the mask layer to be below room temperature; and the moving mechanism is used for driving the nozzle to move relative to the cathode substrate. Through the temperature gradient of the high-temperature working liquid and the low-temperature liquid mask, a thermal Marangoni convection is induced at the liquid-liquid interface, the convection can effectively update the concentration boundary layer, the high-concentration ions in the body are continuously sucked to the deposition interface, the mass transfer bottleneck at room temperature is broken, and the limiting current density and the deposition rate are greatly improved.

Description

Technical Field

[0001] This invention relates to the fields of micro / nano manufacturing and electrochemical additive manufacturing, and more specifically, to a confined electrodeposition apparatus, system, and method based on two-phase temperature control. Background Technology

[0002] Electrodeposition is a metal additive manufacturing technology based on the principle of electrochemical cathode deposition, which has advantages such as no residual stress, low energy consumption, and high resolution. Jet electrodeposition, as an important branch of this technology, achieves localized electrodeposition by spraying a working fluid at high speed onto a cathode substrate, and is widely used in fields such as microelectromechanical systems (MEMS) and chip packaging.

[0003] However, existing jet electrodeposition technology has the following drawbacks: First, it suffers from poor localization, resulting in severe stray deposition and insufficient forming accuracy. Second, it has a low ion diffusion coefficient at room temperature, limiting mass transfer efficiency. While increasing the jet velocity can enhance mass transfer, the high-speed jet easily erodes and damages the deposited microstructure, leading to edge passivation or breakage. Decreasing the jet velocity worsens mass transfer, intensifies concentration polarization, and reduces deposition quality. Therefore, how to overcome the mass transfer bottleneck while ensuring forming accuracy is a pressing technical problem to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to overcome the contradiction in existing electrodeposition technology where room temperature mass transfer capability is severely limited, while traditional mass transfer enhancement methods such as increasing jet velocity lead to a decrease in forming accuracy and structural stability. This invention provides a confined electrodeposition device, system, and method based on two-phase temperature control to achieve a synergistic improvement in mass transfer efficiency and processing localization.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A confined electrodeposition apparatus based on two-phase temperature control is provided, comprising a platform, a cathode substrate mounted on the platform, a moving mechanism mounted on the platform, a nozzle mounted on the moving end of the moving mechanism, a heating component disposed on the liquid supply path of the nozzle, and a cooling component mounted on the platform; the heating component is used to heat the working liquid entering the nozzle to above room temperature; a water flow channel is provided inside the nozzle; a mask layer is deposited on the surface of the cathode substrate, and the cooling component is used to cool the mask layer to below room temperature; the moving mechanism is used to drive the nozzle to move relative to the cathode substrate.

[0006] The core concept of the device of this invention lies in constructing a non-uniform temperature field between a high-temperature working liquid phase and a low-temperature liquid mask phase. The temperature gradient between the two phases drives thermally induced Marangoni convection, thereby achieving a synergistic effect of enhanced mass transfer and boundary constraints. Specifically, the heating component heats the working liquid to above room temperature, giving it high solubility, high ion concentration, and low viscosity, thus improving mass transfer capacity from the source. Simultaneously, the cooling component cools the liquid mask layer coated on the cathode substrate surface to below room temperature, increasing the mask's viscosity and interfacial tension, forming a stable physical constraint boundary. When the high-temperature working liquid is sprayed onto the cathode substrate surface through a nozzle, it displaces the low-temperature liquid mask layer, forming a local reaction zone. A steep temperature gradient is formed at the liquid-liquid interface between the high-temperature working liquid and the low-temperature mask. Since the interfacial tension decreases with increasing temperature, this temperature gradient induces a surface tension gradient, which in turn drives thermally induced Marangoni convection. This convection forms a circulating vortex around the reaction zone, continuously entraining high-concentration metal ions from the bulk working liquid to the deposition interface, achieving renewal of the concentration boundary layer and suppressing concentration polarization. Simultaneously, the reacted working fluid, constrained by interfacial tension and its own buoyancy, is discharged upwards along the outer wall of the nozzle, forming a stable annular microchannel. The moving mechanism can drive the nozzle to perform three-dimensional motion relative to the cathode substrate, achieving scanning deposition along a preset path. Through the synergistic cooperation of the above components, the device of this invention can significantly improve the local mass transfer rate while ensuring clear deposition boundaries.

[0007] Furthermore, a liquid tank is provided on the platform, and the cathode substrate and the mask layer are located within the liquid tank. The liquid tank is used to contain the liquid mask medium, preventing it from overflowing, and at the same time provides a structural basis for the thermal coupling between the cooling components and the mask layer.

[0008] Furthermore, the cooling assembly includes a thermoelectric cooler attached to the sidewall of the liquid tank. The cold end of the thermoelectric cooler is thermally coupled to the mask layer via heat transfer fasteners. The thermoelectric cooler is small in size, has a fast response, and is free from mechanical vibration, making it suitable for precision electrodeposition environments. The heat transfer fasteners (such as thermally conductive metal plates or thermally conductive silicone grease) ensure that the thermal resistance between the cold end and the mask medium is minimized.

[0009] Furthermore, the medium of the mask layer is a fluorinated liquid. Fluorinated liquids have high density, are immiscible with common working fluids, and possess excellent electrical insulation and chemical inertness. They can maintain a stable interface morphology under the impact of high-temperature working fluids and will not contaminate the working fluid or participate in electrochemical reactions.

[0010] Furthermore, the thickness of the mask layer is 0.5mm-1mm. This thickness range effectively isolates non-target areas and suppresses stray deposition, without being too thick to reduce heat transfer efficiency or affect the relative movement between the nozzle and the substrate.

[0011] Furthermore, the heating assembly includes a thermostatic element with an internal thermostatic chamber and a heating element electrically connected to the thermostatic element. The thermostatic chamber is connected to the water flow channel, and the thermostatic element is connected to the moving end of the moving mechanism. The thermostatic chamber is located upstream of the nozzle to ensure that the working fluid is uniformly heated to a preset temperature before entering the nozzle, thus avoiding heat loss along the flow path.

[0012] The present invention also provides an electrodeposition system, including a liquid supply module, a power supply module, and a confined electrodeposition device based on two-phase temperature control as described in any one of the above claims; the anode of the power supply module is electrically connected to an electrode, the electrode being located on the liquid supply path of the nozzle, and the cathode of the power supply module is electrically connected to the cathode substrate; the liquid supply module is connected to the water flow channel through a pipeline.

[0013] The electrodeposition system of this invention delivers working fluid to the nozzle at a controllable flow rate via a liquid supply module, and applies an electrodeposition potential between the anode and cathode via a power supply module, forming a closed electrochemical circuit. The liquid supply module works in conjunction with a heating assembly to ensure the working fluid remains at a high temperature and high concentration upon reaching the nozzle outlet; the power supply module can provide constant current or constant voltage modes. Combining the self-driven thermally induced Marangoni convection and liquid mask boundary constraints of the aforementioned device, the system can achieve stable, efficient, and high-precision electrodeposition processing in micro-regions.

[0014] The present invention also provides an electrodeposition method, comprising the following steps: S1: Heat the electrodeposition working solution to a first temperature to make the working solution have a high ion concentration and low viscosity, wherein the first temperature is higher than room temperature; S2: A mask layer that is immiscible with the working fluid is deposited on the surface of the cathode substrate, and the mask layer is cooled to a second temperature to increase the viscosity and interfacial tension of the mask. The second temperature is lower than room temperature. S3: The working fluid is sprayed onto the cathode substrate surface at a preset flow rate through the nozzle, dispersing the mask layer to form a local reaction zone, and an electrodeposition electric field is applied between the nozzle and the cathode substrate; a temperature gradient is formed between the high-temperature working fluid and the low-temperature mask layer at the liquid-liquid interface, inducing a surface tension gradient, driving thermally induced Marangoni convection to enhance mass transfer. S4: Drive the nozzle to move relative to the cathode substrate, scan and deposit along a preset path to construct a three-dimensional metal microstructure.

[0015] Preferably, the first temperature is 90℃-95℃, and the second temperature is 5℃-15℃.

[0016] Preferably, the preset flow rate is 1m / s-5m / s.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. By using the temperature gradient between the high-temperature working fluid and the low-temperature liquid mask, thermally induced Marangoni convection is generated at the interface of the liquid surface. This convection can effectively renew the concentration boundary layer and continuously entrain high-concentration ions from the bulk to the deposition interface, breaking through the room temperature mass transfer bottleneck and significantly improving the limiting current density and deposition rate.

[0018] 2. The liquid mask layer is independently cooled to a low temperature by a semiconductor cooling chip, which increases the viscosity and interfacial tension of the mask, forms a stable physical constraint boundary, effectively suppresses the lateral spread of the working fluid on the substrate surface and stray deposition in non-target areas, and ensures the edge steepness and dimensional accuracy of the deposited structure. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a confined electrodeposition device based on two-phase temperature control, as described in Example 1. Figure 2 This is a schematic diagram of an electrodeposition system according to Example 2.

[0020] In the attached diagram: 10, platform; 11, liquid tank; 20, cathode substrate; 21, mask layer; 30, moving mechanism; 40, nozzle; 50, heating assembly; 51, heating element; 52, thermostatic element; 60, cooling assembly; 70, power supply module; 71, electrode; 80, liquid supply module. Detailed Implementation

[0021] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0022] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0023] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," and "fitting," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] In the description of this specification, references to terms such as "embodiment" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0025] Example 1 This embodiment is the first embodiment of a confined electrodeposition device based on two-phase temperature control.

[0026] like Figure 1 As shown, the device in this embodiment includes: a platform 10, a cathode substrate 20 mounted on the platform 10, a moving mechanism 30 mounted on the platform 10, a nozzle 40 mounted on the moving end of the moving mechanism 30, a heating assembly 50 disposed on the liquid supply path of the nozzle 40, and a cooling assembly 60 mounted on the platform 10.

[0027] like Figure 1 As shown, the nozzle 40 has a water flow channel inside and the inner diameter of the nozzle 40 is 100μm. The heating assembly 50 includes a constant temperature element 52 with a constant temperature cavity inside and a heating element 51 electrically connected to the constant temperature element 52. The constant temperature cavity is connected to the water flow channel. The constant temperature element 52 is connected to the moving end of the moving mechanism 30 and is used to heat the flowing working fluid to 95°C.

[0028] like Figure 1 As shown, a liquid tank 11 is provided on the platform 10, and the cathode substrate 20 is fixed to the bottom surface of the liquid tank 11. The cathode substrate 20 is a polished copper plate, and a fluorinated liquid is laid on the surface of the cathode substrate 20 as a mask layer 21 with a thickness of 1 mm.

[0029] like Figure 1As shown, the cooling assembly 60 includes a semiconductor cooling chip attached to the side wall of the liquid tank 11. Its cold end is thermally coupled to the mask layer 21 through a heat-conducting copper plate, thereby cooling the mask layer 21 and maintaining its temperature at 10°C.

[0030] The moving mechanism 30 is a three-axis precision displacement mechanism used to drive the nozzle 40 to move relative to the cathode substrate 20.

[0031] The working principle of the device in this embodiment is as follows: The copper sulfate working solution is fed into the constant temperature chamber through a pipeline and heated to 95°C before entering the water flow channel of the nozzle 40. The heated high-temperature working solution is ejected from the nozzle 40 outlet, impacting the surface of the cathode substrate 20 and displacing the low-temperature fluorinated liquid mask layer 21 to form a local reaction zone. An 85°C temperature difference is formed at the interface between the high-temperature working solution and the low-temperature mask, generating a surface tension gradient that drives thermally induced Marangoni convection. This convection forms a circulating vortex around the reaction zone, continuously entraining high-concentration copper ions in the bulk working solution to the deposition interface. At the same time, the post-reaction working solution is discharged upward along the outer wall of the nozzle 40 to form an annular microchannel. The nozzle 40 can be driven to move along a preset path by operating the moving mechanism 30 to achieve fixed-point or scanning deposition.

[0032] This device provides a stable physical environment for highly localized and efficient electrodeposition through the synergistic effect of high-temperature intrinsic mass transfer enhancement, Marangoni convection entrainment to renew the boundary layer, and low-temperature masking to constrain the boundary.

[0033] Example 2 This embodiment provides a specific implementation of an electrodeposition system, which includes the apparatus described in Embodiment 1, and further integrates a liquid supply module 80 and a power supply module 70.

[0034] The electrodeposition apparatus adopts a structure that is basically the same as that in Embodiment 1, specifically including a platform 10, a three-axis moving mechanism 30, a nozzle 40, a heating component 50, a liquid tank 11, a cathode substrate 20, a fluorinated liquid mask layer 21, and a cooling component 60.

[0035] like Figure 2 As shown, the liquid supply module 80 includes a liquid supply tank, a liquid supply pipeline, and a precision injection pump. The liquid supply tank stores copper sulfate working solution, which is a mixture of a 200 g / L CuSO4 solution and a 60 g / L H2SO4 solution. The precision injection pump delivers the working solution to the constant temperature chamber through the insulated liquid supply pipeline at a flow rate of 1 mL / min. The constant temperature chamber integrates a heating rod and a temperature sensor. The controller stabilizes the working solution temperature at 95°C. The heated working solution directly enters the water flow channel of the nozzle 40.

[0036] like Figure 2As shown, the power supply module 70 includes a DC power supply, an anode electrode 71, and wires. The anode electrode 71 is made of copper wire. One end of the electrode 71 is connected to the positive output terminal of the power supply through a wire, and the other end is inserted into the constant temperature chamber and immersed in the working fluid. The negative output terminal of the power supply is electrically connected to the cathode substrate 20 through a wire. The connection point is located on the side of the substrate. In this embodiment, the current is set to 1mA.

[0037] Example 3 This embodiment provides a specific implementation of an electrodeposition method. This method is applicable to the electrodeposition system described in Embodiment 2. This embodiment uses the preparation of a copper micropillar array as an example for illustration.

[0038] The specific steps of the method are as follows: S1: Provides a constant temperature chamber to heat the copper sulfate working solution and maintain it at 95°C, so that the working solution has a high ion concentration and low viscosity.

[0039] S2: A fluorinated liquid mask layer 21 with a thickness of 1 mm is deposited on the surface of the cathode substrate 20. The mask layer 21 is cooled to 10°C by a semiconductor cooling chip to increase its viscosity and interfacial tension.

[0040] S3: A high-temperature working fluid is sprayed onto the surface of the cathode substrate 20 at a flow rate of 3 m / s through nozzle 40. The nozzle 40 has an inner diameter of 100 μm and a distance of 100 μm between it and the substrate. The high-temperature jet displaces the low-temperature mask layer 21, forming a local reaction zone with a diameter of approximately 80 μm on the substrate. Simultaneously, a constant current electrodeposition electric field of 1 mA is applied between the anode of nozzle 40 and the cathode substrate 20. An 85°C temperature gradient is formed at the interface between the high-temperature working fluid and the low-temperature mask, inducing a surface tension gradient and driving thermally induced Marangoni convection. This convection forms a circulating vortex around the reaction zone, continuously entraining high-concentration copper ions from the bulk working fluid to the deposition interface, suppressing concentration polarization. After the reaction, the working fluid is discharged upward along the outer wall of nozzle 40, forming an annular microchannel.

[0041] S4: The nozzle 40 is driven to move relative to the cathode substrate 20 via a three-axis motion mechanism, performing fixed-point scanning deposition along a preset 10×10 array path. The point spacing is set to 300μm, and the deposition time per point is 5 seconds.

[0042] S5: After deposition, the power supply and liquid supply were turned off, nozzle 40 was removed, and cathode substrate 20 was taken out. The substrate was ultrasonically cleaned with deionized water to remove residual mask and working solution. Microscopic observation revealed a regularly arranged array of copper micropillars on the surface of cathode substrate 20. The micropillars were approximately 80 μm in diameter and 28 μm in height, with good surface quality, no obvious coarse grains, and no stray deposited particles around the array. In contrast, under the same deposition current of 1 mA, the same deposition time of 5 s per point, and the same nozzle 40 substrate spacing of 100 μm, using a working solution at room temperature (25°C) and without a liquid mask layer 21, the single-point deposition height was only 8 μm. The deposition height in this embodiment is more than three times that of the control sample, and the edge steepness is significantly better.

[0043] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0044] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A confined electrodeposition device based on two-phase temperature control, characterized in that, The device includes a platform (10), a cathode substrate (20) mounted on the platform (10), a moving mechanism (30) mounted on the platform (10), a nozzle (40) mounted on the moving end of the moving mechanism (30), a heating assembly (50) disposed on the liquid supply path of the nozzle (40), and a cooling assembly (60) mounted on the platform (10). The heating assembly (50) is used to heat the working fluid entering the nozzle (40) to above room temperature. A water flow channel is provided inside the nozzle (40). A mask layer (21) is laid on the surface of the cathode substrate (20), and the cooling assembly (60) is used to cool the mask layer (21) to below room temperature. The moving mechanism (30) is used to drive the nozzle (40) to move relative to the cathode substrate (20).

2. The confined electrodeposition apparatus based on two-phase temperature control according to claim 1, characterized in that, A liquid tank (11) is provided on the platform (10), and the cathode substrate (20) and the mask layer (21) are located in the liquid tank (11).

3. The confined electrodeposition apparatus based on two-phase temperature control according to claim 2, characterized in that, The cooling assembly (60) includes a semiconductor refrigeration chip attached to the sidewall of the liquid tank (11), and the cold end of the semiconductor refrigeration chip is thermally coupled to the mask layer (21) through a heat transfer fastener.

4. The confined electrodeposition apparatus based on two-phase temperature control according to claim 1, characterized in that, The medium of the mask layer (21) is a fluorinated liquid.

5. The confined electrodeposition apparatus based on two-phase temperature control according to claim 1, characterized in that, The thickness of the mask layer (21) is 0.5mm-1mm.

6. The confined electrodeposition apparatus based on two-phase temperature control according to claim 1, characterized in that, The heating assembly (50) includes a constant temperature element (52) with a constant temperature cavity inside and a heating element (51) electrically connected to the constant temperature element (52). The constant temperature cavity is connected to the water flow channel, and the constant temperature element (52) is connected to the moving end of the moving mechanism (30).

7. An electrodeposition system, characterized in that, The device includes a liquid supply module (80), a power supply module (70), and a confined electrodeposition apparatus based on two-phase temperature control as described in any one of claims 1-6; the anode of the power supply module (70) is electrically connected to an electrode (71), the electrode (71) is located on the liquid supply path of the nozzle (40), and the cathode of the power supply module (70) is electrically connected to the cathode substrate (20); the liquid supply module (80) is connected to the water flow channel through a pipeline.

8. An electrodeposition method, characterized in that, Includes the following steps: S1: Heat the electrodeposition working solution to a first temperature to make the working solution have a high ion concentration and low viscosity, wherein the first temperature is higher than room temperature; S2: A mask layer (21) that is immiscible with the working fluid is deposited on the surface of the cathode substrate (20), and the mask layer (21) is cooled to a second temperature to increase the viscosity and interfacial tension of the mask. The second temperature is lower than room temperature. S3: The working fluid is sprayed onto the surface of the cathode substrate (20) at a preset flow rate through the nozzle (40), the mask layer (21) is displaced to form a local reaction zone, and an electrodeposition electric field is applied between the nozzle (40) and the cathode substrate (20); A temperature gradient is formed at the liquid-liquid interface between the high-temperature working fluid and the low-temperature mask layer (21), which induces a surface tension gradient and drives thermally induced Marangoni convection to enhance mass transfer. S4: Drive the nozzle (40) to move relative to the cathode substrate (20), scan and deposit along a preset path to construct a three-dimensional metal microstructure.

9. The electrodeposition method according to claim 8, characterized in that, The first temperature is 90℃-95℃, and the second temperature is 5℃-15℃.

10. The electrodeposition method according to claim 8, characterized in that, The preset flow rate is 1m / s-5m / s.

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