Method and apparatus for manufacturing metal microstructure with nanometer layer thickness deposition precision

Abstract

The present application relates to a kind of nanometer layer thickness deposition precision metal microstructure preparation method and equipment method, and preparation silicon rubber microneedle tip seal with micro-nano hole;High concentration ion content metal electrolyte is placed in the liquid storage cavity of silicon rubber microneedle tip seal, as a constant mass transfer element, using the self-diffusion effect of electrolyte in silicon rubber from high concentration direction to low concentration direction, realize the electrolyte of ultrathin layer thickness to be accumulated on base;Again using the mode of electrodeposition, the electrolyte metal ion that is transferred to the position of conductive base by micro-nano hole is reduced into metal microstructure.The metal microstructure formed by the preparation method of the present application has excellent mechanical strength, chemical corrosion resistance, thermal conductivity and electrical conductivity, etc.;Avoid the complicated multi-step production process of traditional metal ink deposition and subsequent heat treatment, etc., can meet the different requirements of different users for three-dimensional pattern, large height-width ratio geometric dimension, etc.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology for 3D metal microstructures, and in particular to a method and equipment for preparing metal microstructures with nanoscale layer thickness deposition precision. Background Technology

[0002] Functional 3D microdevices are widely used in aerospace, military, semiconductor electronics, biomedicine, adaptive optics, wireless communication, biotechnology, and automotive fields. While silicon-based materials offer excellent strength, their poor toughness and weak impact energy absorption increase the design complexity and manufacturing integration costs of microdevices. Using metals (such as gold, nickel, copper, stainless steel, or alloys) as bulk materials offers excellent mechanical strength, chemical corrosion resistance, thermal conductivity, and electrical conductivity, attracting widespread attention in the development of functional 3D microdevices. Precision fabrication and related process innovations for metal-based 3D micro / nano structures have become important research areas in microsystems manufacturing.

[0003] Traditional semiconductor device fabrication techniques are difficult to directly apply to the fabrication of metal-based 3D microdevices, and the resulting devices have small aspect ratios. Current state-of-the-art manufacturing technologies for metal microstructures primarily utilize additive manufacturing, but these researches and fabrications suffer from the following limitations:

[0004] 1. In digital piezoelectric or thermal inkjet printing methods, the manufacturing process usually includes optimized design of metal nanoparticle dispersion, pretreatment of substrate material surface modification, and post-processing annealing, which to some extent limits the processing speed and affects manufacturing performance. Furthermore, the size of the printing nozzle diameter, the dispersion effect of the metal ink, and the surface tension of the ink impose certain limitations on the feature resolution of the manufacturable parts.

[0005] 2. In electrodeposition methods, template-based manufacturing techniques rely on the pre-preparation of templates, making it difficult to extend to applications with high aspect ratio requirements. Furthermore, freeform techniques, such as those using electrochemical scanning probes combined with nanoelectrodes and nanocapillaries, still face practical challenges in terms of ease of operation, high resolution, batch production, and controllable quality repeatability. Summary of the Invention

[0006] To address the shortcomings of existing production technologies, this applicant provides a method and equipment for preparing metal microstructures with reasonable nanolayer thickness deposition precision. By limiting the ion flow rate through micro- and nano-pores and ensuring that the electrolyte layer reaches the expected thickness under the premise of self-diffusion, the metal microstructures prepared using this ion array method can form three-dimensional metal microdevices with excellent mechanical strength, chemical corrosion resistance, thermal conductivity, and electrical conductivity.

[0007] The technical solution adopted in this invention is as follows:

[0008] A method for preparing metal microstructures with nanoscale layer thickness deposition precision includes the following steps:

[0009] An electrolyte is injected into the liquid carrier container of the preparation equipment. The electrolyte is a metal ion solution. The metal ion solution is released through the micro-nano pores of the liquid carrier container by self-diffusion under the condition of its own concentration difference with the external concentration.

[0010] The diffused metal ion solution forms an electrolyte layer with a thickness of less than 10 nm on the deposition substrate of the preparation equipment. Conductive current is applied between the electrolyte layer and the deposition substrate. During this process, metal cations in the electrolyte diffuse out of the microneedle tip of the liquid carrier container and are reduced to elemental metal.

[0011] The reduced single-layer metal element is deposited on the deposition substrate. The preparation equipment drives the deposition substrate to descend a predetermined distance, which serves as a reserved space for the next layer of metal deposition, until the metal is stacked on the deposition substrate to form a three-dimensional metal microstructure.

[0012] Throughout the process, the contact force between the liquid container and the deposition substrate is constantly monitored.

[0013] As a further improvement to the above technical solution:

[0014] The specific steps for establishing electrical conductivity between the electrolyte layer and the deposition substrate are as follows:

[0015] The metal ion solution is poured into a carrier liquid container and used as a constant mass transfer element.

[0016] A metal electrode is inserted into the liquid-carrying chamber of the liquid-carrying container. The metal electrode is connected to the positive terminal of an external voltage source device, and the negative terminal of the voltage source device is connected to the deposition substrate.

[0017] When the microneedles of the liquid carrier come into contact with the deposition substrate, this closed-loop circuit is activated, forming an electrochemical deposition system.

[0018] The fabrication equipment used in a method for preparing metallic microstructures with nanolayer deposition precision includes a coarse positioning system and a fine positioning system.

[0019] The coarse positioning system includes:

[0020] An electrically driven slide table, mounted on a flat surface, has a liquid-carrying container installed on it.

[0021] A contact force sensor is slidably connected to the electrically driven slide table, and maintains a monitoring state during the movement of the slide table.

[0022] The precise positioning system includes:

[0023] The piezoelectric nanostage is located on the plane of the electrically driven slide, and below the liquid container on the electrically driven slide.

[0024] The deposited substrate is slidably connected to a piezoelectric nanodisplacement stage, and the metal ion solution diffused from the liquid container falls onto the deposited substrate.

[0025] A liquid-carrying container has several microneedles at its bottom, and micro-nano pores are formed inside the liquid-carrying container and the microneedles. The electrolyte contained in the liquid-carrying chamber of the liquid-carrying container flows out from the pores of the micro-nano pores.

[0026] The pore size of the micro-nano pores ranges from 1 nm to 100 nm.

[0027] A method for preparing a liquid-carrying container for fabricating a metal microstructure with nanolayer deposition precision includes the following steps:

[0028] A template with an array of microneedle-shaped recesses on its surface was prepared.

[0029] The liquid storage cavity mold is fixed on the template of the concave hole array. Silicone rubber material is injected into the liquid storage cavity mold. After heating and curing, the mold is demolded to obtain a liquid carrier container with microneedles made of silicone rubber.

[0030] During the molding process of the liquid carrier container, at least one of the following methods is used: solute doping sacrificial method, organic solvent cleaning method, and hydrophilic group grafting method to form micro-nano pores in silicone rubber material.

[0031] As a further improvement to the above technical solution:

[0032] The specific steps of the solute doping sacrificial method are as follows:

[0033] Micro- and nano-particles are doped into silicone rubber material. After the silicone rubber is cured and shaped, the doped micro- and nano-particles are washed away with deionized water solvent, so that micro- and nano-pores are formed in the silicone rubber at the original positions of the micro- and nano-particles.

[0034] The specific steps of the organic solvent cleaning method are as follows:

[0035] Using a solvent, the fully cross-linked thermosetting silicone rubber is pre-cleaned to remove uncross-linked silicone rubber molecules and form micro-nano porous channels.

[0036] The specific steps of the hydrophilic group grafting method are as follows:

[0037] Polymer surfactants are added to silicone rubber to anchor hydrophilic groups in the cured silicone rubber, thus forming silicone rubber with hydrophilic properties.

[0038] The metal ion solution is one or more of the following metal ions: copper, iron, chromium, nickel, zinc, etc.

[0039] The beneficial effects of this invention are as follows:

[0040] The preparation method provided by this invention effectively controls the thickness of the ultrathin deposition layer through the self-diffusion mechanism of the metal electrolyte, which has not been reported in the industry or in patent investigations.

[0041] Precision array manufacturing utilizes the micro-contact printing mechanism to achieve a novel process for controlling the micro-contact surface interface during the layer-by-layer deposition process;

[0042] The present invention achieves an ultrathin deposition layer thickness control capability of <10nm, which mainly depends on the comprehensive matching of contact time, contact force, electrolyte type, and electric field parameters between different surfaces during the self-diffusion process;

[0043] The present invention achieves a high planar structural feature resolution of <1µm. It uses a piezoelectric-driven nanometer-precision motion platform as the main hardware and integrates and optimizes the whole to ensure precise control of layer thickness. By using silicon-based MEMS / NEMS processing technology, high-quality submicron and below precision cone or needle tip arrays can be manufactured on silicon substrates. Through fine silicone rubber molding operations, silicone rubber stamps with soft needle tip arrays can be precisely manufactured. By combining, for example, high-precision contact force feedback control, the needle tip contact deformation during the manufacturing process can be optimized to achieve higher resolution.

[0044] This invention has many advantages, such as good molding, high continuity, uninterrupted process, and mass production capability, saving manpower, time, and production costs. Attached Figure Description

[0045] Figure 1 This is a schematic diagram illustrating the principle of the metal three-dimensional microstructure manufacturing method based on the self-diffusion mechanism of electrolyte in silicone rubber according to the present invention.

[0046] Figure 2 This is a schematic diagram of the mold structure for preparing the liquid-carrying container according to the present invention.

[0047] Figure 3 This is a cross-sectional view of the mold structure for preparing the liquid-carrying container according to the present invention.

[0048] Figure 4 This is a schematic diagram of the liquid-carrying container structure of the present invention.

[0049] Figure 5 This is a schematic diagram of the liquid-carrying container of the present invention from another perspective.

[0050] Figure 6 This is a microscopic schematic diagram of the liquid-carrying container of the present invention.

[0051] Figure 7 for Figure 6 The magnified view is used to show the flow direction of the metal ion solution inside the liquid container.

[0052] Figure 8 This is a schematic diagram of the preparation equipment of the present invention.

[0053] Figure 9 This is a flowchart of the preparation process of the present invention.

[0054] The components include: 1. Liquid container; 2. Coarse positioning system; 3. Fine positioning system; 4. Electrode; 5. Voltage source; 6. Current monitoring device; 7. Electrolyte; 8. Mold; 9. Template;

[0055] 101. Microneedle; 102. Fluid-carrying chamber;

[0056] 201. Electrically driven slide table; 202. Contact force sensor;

[0057] 301. Deposition substrate; 302. Piezoelectric nanodisplacement stage. Detailed Implementation

[0058] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0059] like Figures 1-9 As shown, the method for preparing metal microstructures with nanoscale layer thickness deposition precision in this embodiment includes the following steps:

[0060] Electrolyte 7 is injected into the liquid carrier container 1 of the preparation equipment. Electrolyte 7 is a metal ion solution. The metal ion solution is released by self-diffusion through the micro-nano pores of the liquid carrier container 1 under the condition of its own concentration and the concentration difference of the outside.

[0061] The diffused metal ion solution forms an electrolyte 7 layer with a thickness of less than 10 nm on the deposition substrate 301 of the preparation device. The electrolyte 7 layer and the deposition substrate 301 are conductive and a DC voltage is applied. During this process, the metal cations in the electrolyte 7 diffuse out from the tip of the microneedle 101 of the liquid carrier 1 and are reduced to metal elements.

[0062] The reduced single-layer metal element is deposited on the deposition substrate 301. The preparation equipment drives the deposition substrate 301 to descend a predetermined distance, which serves as a reserved space for the next layer of metal deposition, until the metal three-dimensional microstructure is stacked on the deposition substrate 301.

[0063] Throughout the above process, the contact force between the monitoring liquid container 1 and the deposition substrate 301 is maintained.

[0064] The specific steps for establishing electrical conductivity between the electrolyte layer 7 and the deposition substrate 301 are as follows:

[0065] The metal ion solution is poured into liquid carrier container 1, which serves as a constant mass transfer element.

[0066] A metal electrode 4 is inserted into the liquid-carrying chamber 102 of the liquid-carrying container 1. The metal electrode 4 is connected to the positive terminal of the external voltage source 5 device, and the negative terminal of the voltage source 5 device is connected to the deposition substrate 301.

[0067] When the microneedle 101 of the liquid carrier 1 comes into contact with the deposition substrate 301, this closed-loop circuit is turned on, forming an electrochemical deposition system.

[0068] The fabrication equipment used in the method for preparing metal microstructures with nanolayer deposition precision in this embodiment includes a coarse positioning system 2 and a fine positioning system 3.

[0069] Coarse positioning system 2 includes:

[0070] An electrically driven slide 201 is mounted on a flat surface, and a liquid container 1 is installed on the electrically driven slide 201.

[0071] The contact force sensor 202 is slidably connected to the electric drive slide table 201, and the contact force sensor 202 maintains a monitoring state during the movement of the electric drive slide table 201.

[0072] The precision positioning system 3 includes:

[0073] The piezoelectric nanostage 302 is located on the plane of the electrically driven slide 201 and below the liquid container 1 on the electrically driven slide 201.

[0074] The deposition substrate 301 is slidably connected to the piezoelectric nano-displacement stage 302, and the metal ion solution diffused from the liquid container 1 falls onto the deposition substrate 301.

[0075] The liquid carrier 1 used in the method for preparing metal microstructures with nanolayer deposition precision in this embodiment has a plurality of microneedles 101 at the bottom. Micro-nano pores are formed inside the liquid carrier 1 and the microneedles 101. The electrolyte 7 contained in the liquid carrier cavity 102 of the liquid carrier 1 flows out from the pores of the micro-nano pores.

[0076] The liquid carrier 1 used in the method for preparing metal microstructures with nanolayer deposition precision as described in claim 4 of this embodiment has a pore size range of 1 nm to 100 nm.

[0077] The preparation method of the liquid carrier container 1 used in the method for preparing metal microstructures with nanolayer deposition precision in this embodiment includes the following steps:

[0078] Template 9 with a surface array of microneedle-shaped recesses was prepared.

[0079] The liquid storage cavity mold 8 is fixed on the template 9 of the concave hole array. Silicone rubber material is injected into the liquid storage cavity mold 8. After heating and curing, the mold is demolded to obtain a liquid carrier container 1 with microneedles 101 made of silicone rubber.

[0080] During the molding process of the liquid carrier 1, at least one of the following methods from this embodiment is used: solute doping sacrificial method, organic solvent cleaning method, and hydrophilic group grafting method to form micro-nano pores in silicone rubber material.

[0081] The specific steps of the solute doping sacrificial method are as follows:

[0082] Micro- and nano-particles are doped into silicone rubber material. After the silicone rubber is cured and shaped, the doped micro- and nano-particles are washed away with deionized water solvent, so that micro- and nano-pores are formed in the silicone rubber at the original positions of the micro- and nano-particles.

[0083] The specific steps of the organic solvent cleaning method are as follows:

[0084] Using a solvent, the fully cross-linked thermosetting silicone rubber is pre-cleaned to remove uncross-linked silicone rubber molecules and form micro-nano porous channels.

[0085] The specific steps of the hydrophilic group grafting method are as follows:

[0086] Polymer surfactants are added to silicone rubber to anchor hydrophilic groups in the cured silicone rubber, thus forming silicone rubber with hydrophilic properties.

[0087] The metal ion solution is one or more of the following metal ions: copper, iron, chromium, nickel, zinc, etc.

[0088] The specific equipment and working principle of this invention are as follows:

[0089] The key point of this invention lies in utilizing, for example Figure 1 The electrodeposition system shown in the figure allows a metal ion solution to diffuse onto the deposition substrate, reducing it to obtain a metal microstructure.

[0090] Figure 1 In the figure, the liquid carrier container holds a metal ion solution, and the concentration gradually decreases from the electrode to the periphery. After the metal ion solution with a high concentration of ions is placed in the liquid carrier container, the liquid carrier container acts as a constant mass transfer element. Utilizing the self-diffusion effect of the electrolyte within the silicone rubber from the high concentration direction to the low concentration direction, an ultra-thin layer of electrolyte is deposited on the deposition substrate.

[0091] The electrolyte self-diffusion mechanism mentioned in this embodiment refers to the process of using metal electrolyte to flow from high concentration to low concentration through the micro-nano pore channels in silicone rubber to achieve ultra-thin and ultra-micro mass transfer.

[0092] The silicone rubber material is one or more of dimethyl silicone rubber, ethyl silicone rubber, methyl vinyl silicone rubber, and methyl phenyl vinyl silicone rubber. The liquid-carrying container made of silicone rubber is obtained through casting molding and demolding. The specific steps are: First, using one or more precision machining techniques such as two-photon 3D printing photoresist technology, high-precision laser etching silicon wafer technology, and anodized aluminum preparation technology, a template with a surface array of pointed and recessed holes is manufactured; Second, referring to… Figure 2 and Figure 3 The process involves: 1) fixing the liquid storage cavity mold onto the template of the concave hole array; 2) injecting the aforementioned silicone rubber material from the top pouring port of the liquid storage cavity mold; 3) placing the template, mold, and silicone rubber in an oven and heating to cure the silicone rubber and maintain its shape; 4) removing the mold and template to complete the preparation of the silicone rubber liquid carrier container.

[0093] The liquid-carrying container can be one or more of the following shapes: cylindrical, conical, pyramidal, and prismatic; the microneedle array can be one or more of the following forms: rectangular array, circular array, and arc-shaped array; the microneedle size is optional.

[0094] The aspect ratio is 10:1 to 1:1;

[0095] Root size is 1-100μm;

[0096] The end size is 0.1-100μm.

[0097] The micro- and nano-pores inside silicone rubber materials can be achieved through the following methods:

[0098] The first method for forming micro-nano pores is the solute doping sacrificial method, which uses micro-nano particles such as soluble salts and soluble organic substances to be doped into silicone rubber materials. After the silicone rubber is cured and shaped, the doped particles are washed away using solvents such as deionized water.

[0099] The second method for forming micro-nano pores is the organic solvent cleaning method. This method uses esters, ketones, or other solvents to pre-clean the thermosetting silicone rubber that has not yet been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules and forming micro-nano pore channels.

[0100] The third method for forming micro-nano pores is the hydrophilic group grafting method. Due to the self-diffusion behavior of metal ions inside silicone, the hydrophobic properties of the silicone rubber material itself reduce the electrolyte diffusion rate, resulting in a slow deposition rate. The hydrophilic group grafting method is used to improve the hydrophilicity of the material. This method specifically refers to using polymeric surfactants such as silicone rubber and ethylene oxide polymers as additives to anchor hydrophilic groups in the cured silicone rubber, forming a stable hydrophilic silicone rubber with ideal overall performance.

[0101] The liquid-carrying containers with micro- and nano-pores obtained by the above methods, such as Figures 4-5As shown, the bottom has microneedles, which also contain micro- and nano-pores to allow the metal ion solution to flow out; the pore size of the micro- and nano-pores is between 1 nm and 100 nm, such as... Figure 6 and Figure 7 As shown, the metal ion solution can flow along... Figure 7 The white arrow in the center indicates diffusion and precipitation.

[0102] Reference Figure 1 When the microneedle comes into contact with the deposition substrate, the diffused electrolyte layer accumulates and is reduced. In this closed loop, a current monitoring device can also be connected as needed. When a DC voltage source is applied between the ultrathin electrolyte at the tip of the microneedle and the conductive substrate, an online monitoring method for the loop current can be used. For example, a waveform generator can be used to control the electrodeposition morphology so that the ultrathin electrolyte layer is reduced to a metallic element and can be controllably deposited on the conductive substrate.

[0103] During the electrodeposition process, piezoelectric platforms with high-precision displacement performance, pressure sensors with high-precision sensing performance, and online monitoring data fusion feedback can be used to control the diffusion behavior of ultra-thin electrolyte layers.

[0104] The electrodeposition process requires the use of Figure 8 The apparatus shown consists of a coarse positioning system placed vertically in the horizontal plane, and a fine positioning system located below it, receiving the metal ion solution. The liquid container on the coarse positioning system is connected to an external voltage source, forming an electrochemical deposition system.

[0105] The vertical movement of the coarse positioning system is achieved by an electrically driven slide, which uses a motor to drive a lead screw to achieve vertical movement. The coarse positioning system is equipped with a contact force sensor. The electrically driven slide brings the liquid container into initial contact with the fine positioning system, and the contact force sensor monitors the magnitude of the contact force during this process.

[0106] The precision positioning system consists of a piezoelectric nano-displacement stage placed in a plane and a deposition substrate located above the piezoelectric nano-displacement stage. The deposition substrate is used to support the diffused electrolyte and the deposited metal layer obtained by electrolyte reduction. After each metal microstructure is reduced, the thickness of the piezoelectric nano-displacement stage decreases by one layer to accommodate the next layer of metal microstructure obtained by reduction.

[0107] Electrochemical deposition systems are used to apply electricity, reduce deposited metal ions, and monitor the current state.

[0108] The specific approach to preparing metal microstructures is as follows:

[0109] S110. Provides a metal electrolyte material and a carrier container; the electrolyte material is a metal ion solution, which is reduced to produce elemental metals under the action of an electric field; the carrier container is made of silicone rubber.

[0110] S120, Provide contact force monitoring and control methods;

[0111] S130, Provides motion control methods for coarse and fine positioning;

[0112] S140 will provide methods for regulating and monitoring electrochemical deposition;

[0113] S150, process parameters for the preliminary self-diffusion electrochemical deposition process;

[0114] S160. The metal ion solution is loaded into the liquid carrier chamber, and a metal electrode is inserted into the liquid carrier chamber. The electrode is connected to the positive terminal of the voltage source device through the current monitoring device of the electrochemical deposition system. The negative terminal of the voltage source device is connected to the deposition substrate.

[0115] S170, The coarse positioning system drives the liquid container to descend until it stops when the contact force sensor senses the initial force;

[0116] S180, the precision positioning system drives the deposition substrate to descend until the initial force mentioned above returns to zero, and then continues to descend to a certain height as a reserved space for the initial layer of metal to be deposited;

[0117] S190. Based on the process parameters of the electrochemical deposition process in the preliminary experiment, the metal cations in the electrolyte diffused and deposited at the end of the microstructure array on the bottom surface of the liquid carrier are reduced to elemental metals.

[0118] S200, the reduced single-layer metal element array is deposited on the substrate, and the nano-precision positioning platform descends to a certain height to reserve space for the next layer of metal deposition. The above deposition process is repeated to stack and form a three-dimensional metal microstructure array.

[0119] The liquid-carrying cavity is used to hold the metal ion solution and can diffuse the metal ion solution to the end of the microstructure. The microstructure array is used for directional diffusion of the metal ion solution and can obtain high lateral deposition resolution by utilizing the fine microstructure.

[0120] The precision positioning system is used to carry the reconstructed metal microstructure and can achieve high longitudinal deposition resolution using a nanoscale precision positioning platform.

[0121] The following provides several embodiments and comparative examples to demonstrate the feasibility and beneficial effects of this solution.

[0122] Example 1:

[0123] (1) Dow Corning Sylgard TM184 substrate, curing agent, PDMS-b-PEO (PEO branch molecular weight of 600) were formulated in a mass ratio of 100:5:1 to prepare a hydrophilically modified low crosslinking silicone rubber fluid material.

[0124] (2) A silicon wafer template with a micro-needle tip concave hole array on the surface is processed using high-precision laser etching silicon wafer technology. The concave holes are frustum-shaped, with a bottom diameter of 10μm, a top diameter of 20μm, and a depth of 30μm. The array is a rectangular array with an array spacing of 50μm.

[0125] (3) A liquid storage cavity mold was manufactured using photopolymerization 3D printing technology. The mold has an inner diameter of 10 mm and a height of 10 mm.

[0126] (4) Place the liquid storage cavity mold above the microneedle tip silicon wafer template prepared in step (2) and press it down. Inject the silicone rubber fluid material prepared in step (1) from the pouring port at the top of the liquid storage cavity mold to fill the microneedle tip concave hole array and the entire liquid storage cavity mold cavity.

[0127] (5) Place the above template, mold, and silicone rubber in an oven, set the temperature to 120°C, and keep it for 2 hours to allow the silicone rubber to complete vulcanization and maintain its shape. Then remove the mold and template to complete the preparation of the silicone rubber microneedle tip stamp.

[0128] (7) Place the prepared silicone rubber microneedle tip stamp in 200ml of ethyl acetate liquid and clean it with ultrasonic vibration for 20 minutes to clean the thermosetting silicone rubber that has not been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules in some areas. Take out the silicone rubber microneedle tip stamp and rinse the remaining ethyl acetate liquid again with deionized water to obtain pore channels of 1nm to 100nm inside the silicone rubber material.

[0129] (8) Build a metal three-dimensional microstructure manufacturing equipment based on the self-diffusion mechanism of electrolyte in silicone rubber, install the silicone rubber microstructure liquid carrier 1 prepared in step (8) on the ion array equipment, use ITO peeling as the deposition substrate 301, and fix it on the piezoelectric nano displacement stage 302.

[0130] (9) Prepare a copper sulfate solution with a high concentration of copper ions of 207 g / L as electrolyte 7. Put the copper sulfate solution into a silicone rubber microstructure carrier container 1 as a constant mass transfer element. Insert a metal electrode 4 into the carrier container 1. The electrode 4 is connected to the positive terminal of the voltage source device 5 through the current monitoring device 6 of the electrochemical deposition system. The negative terminal of the voltage source device 5 is connected to the deposition substrate 301.

[0131] (10) The coarse positioning system 2 drives the liquid container 1 to descend until the contact force sensor 202 senses that the force value is not 0N and stops. At this time, the liquid container 1 contacts the deposition substrate 301.

[0132] (11) The piezoelectric nano-precision positioning platform 302 drives the deposition substrate 301 to descend until the initial force mentioned above returns to zero, and then continues to descend by 10 nm as a reserved space for the initial metal layer deposition.

[0133] (12) Apply a DC voltage of 0.8V between the initial layer electrolyte and the conductive substrate for 10s to reduce the metal cations in the electrolyte diffused from the end of the microstructure array on the bottom surface of the liquid carrier 1 to metal elements. During the deposition process, the contact force sensor 202 monitors the contact force in real time and keeps it within the range of 3 to 5mN.

[0134] (13) The reduced single-layer copper element array is deposited on the deposition substrate 301. The piezoelectric nanoprecision positioning platform 302 drops by 10 nm as a reserved space for the next layer of deposited metal. The above deposition process is repeated to stack and form a metal three-dimensional microstructure array with a layer thickness accuracy of 10 nm.

[0135] Example 2:

[0136] (1) Dow Corning Sylgard TM 184 substrate, curing agent, PDMS-b-PEO (PEO branch molecular weight of 600) were formulated in a mass ratio of 100:5:1 to prepare a hydrophilically modified low crosslinking silicone rubber fluid material.

[0137] (2) A silicon wafer template with a micro-needle tip concave hole array on the surface is processed using high-precision laser etching silicon wafer technology. The concave holes are frustum-shaped, with a bottom diameter of 10μm, a top diameter of 20μm, and a depth of 30μm. The array is a rectangular array with an array spacing of 50μm.

[0138] (3) A liquid storage cavity mold was manufactured using photopolymerization 3D printing technology. The mold has an inner diameter of 10 mm and a height of 10 mm.

[0139] (4) Place the liquid storage cavity mold above the microneedle tip silicon wafer template prepared in step (2) and press it down. Inject the silicone rubber fluid material prepared in step (1) from the pouring port at the top of the liquid storage cavity mold to fill the microneedle tip concave hole array and the entire liquid storage cavity mold cavity.

[0140] (5) Place the above template, mold, and silicone rubber in an oven, set the temperature to 120°C, and keep it for 2 hours to allow the silicone rubber to complete vulcanization and maintain its shape. Then remove the mold and template to complete the preparation of the silicone rubber microneedle tip stamp.

[0141] (7) Place the prepared silicone rubber microneedle tip stamp in 200ml of ethyl acetate liquid and clean it with ultrasonic vibration for 20 minutes to clean the thermosetting silicone rubber that has not been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules in some areas. Take out the silicone rubber microneedle tip stamp and rinse the remaining ethyl acetate liquid again with deionized water to obtain pore channels of 1nm to 100nm inside the silicone rubber material.

[0142] (8) Build a metal three-dimensional microstructure manufacturing equipment based on the self-diffusion mechanism of electrolyte in silicone rubber, install the silicone rubber microstructure liquid carrier 1 prepared in step (8) on the ion array equipment, use ITO peeling as the deposition substrate 301, and fix it on the piezoelectric nano displacement stage 302.

[0143] (9) Prepare a silver nitrate solution with a high concentration of silver ions of 216 g / L as electrolyte 7. Put the silver nitrate solution into a silicone rubber microstructure carrier container 1 as a constant mass transfer element. Insert a metal electrode 4 into the carrier container 1. The electrode 4 is connected to the positive terminal of the voltage source device 5 through the current monitoring device 6 of the electrochemical deposition system. The negative terminal of the voltage source device 5 is connected to the deposition substrate 301.

[0144] (10) The coarse positioning system 2 drives the liquid container 1 to descend until the contact force sensor 202 senses that the force value is not 0N and stops. At this time, the liquid container 1 contacts the deposition substrate 301.

[0145] (11) The piezoelectric nano-precision positioning platform 302 drives the deposition substrate 301 to descend until the initial force mentioned above returns to zero, and then continues to descend by 10 nm as a reserved space for the initial metal layer deposition.

[0146] (12) Apply a DC voltage of 0.8V between the initial layer electrolyte and the conductive substrate for 5s to reduce the metal cations in the electrolyte diffused from the end of the microstructure array on the bottom surface of the liquid carrier 1 to metal elements. During the deposition process, the contact force sensor 202 monitors the contact force in real time and keeps it within the range of 3 to 5mN.

[0147] (13) The reduced single-layer copper element array is deposited on the deposition substrate 301. The piezoelectric nanoprecision positioning platform 302 drops by 10 nm as a reserved space for the next layer of deposited metal. The above deposition process is repeated to stack and form a metal three-dimensional microstructure array with a layer thickness accuracy of 10 nm.

[0148] Comparative Example 1: Effect of electrolyte concentration on self-diffusion rate (low-concentration electrolyte)

[0149] (1) Dow Corning Sylgard TM184 substrate, curing agent, PDMS-b-PEO (PEO branch molecular weight of 600) were formulated in a mass ratio of 100:5:1 to prepare a hydrophilically modified low crosslinking silicone rubber fluid material.

[0150] (2) A silicon wafer template with a micro-needle tip concave hole array on the surface is processed using high-precision laser etching silicon wafer technology. The concave holes are frustum-shaped, with a bottom diameter of 10μm, a top diameter of 20μm, and a depth of 30μm. The array is a rectangular array with an array spacing of 50μm.

[0151] (3) A liquid storage cavity mold was manufactured using photopolymerization 3D printing technology. The mold has an inner diameter of 10 mm and a height of 10 mm.

[0152] (4) Place the liquid storage cavity mold above the microneedle tip silicon wafer template prepared in step (2) and press it down. Inject the silicone rubber fluid material prepared in step (1) from the pouring port at the top of the liquid storage cavity mold to fill the microneedle tip concave hole array and the entire liquid storage cavity mold cavity.

[0153] (5) Place the above template, mold, and silicone rubber in an oven, set the temperature to 120°C, and keep it for 2 hours to allow the silicone rubber to complete vulcanization and maintain its shape. Then remove the mold and template to complete the preparation of the silicone rubber microneedle tip stamp.

[0154] (7) Place the prepared silicone rubber microneedle tip stamp in 200ml of ethyl acetate liquid and clean it with ultrasonic vibration for 20 minutes to clean the thermosetting silicone rubber that has not been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules in some areas. Take out the silicone rubber microneedle tip stamp and rinse the remaining ethyl acetate liquid again with deionized water to obtain pore channels of 1nm to 100nm inside the silicone rubber material.

[0155] (8) Build a metal three-dimensional microstructure manufacturing equipment based on the self-diffusion mechanism of electrolyte in silicone rubber, install the silicone rubber microstructure liquid carrier 1 prepared in step (7) on the ion array equipment, use ITO peeling as the deposition substrate 301, and fix it on the piezoelectric nano displacement stage 302.

[0156] (9) Prepare a copper sulfate solution with a low concentration of copper ions of 50 g / L as electrolyte 7. Put the copper sulfate solution into a silicone rubber microstructure carrier container 1 as a constant mass transfer element. Insert a metal electrode 4 into the carrier container 1. The electrode 4 is connected to the positive terminal of the voltage source device 5 through the current monitoring device 6 of the electrochemical deposition system. The negative terminal of the voltage source device 5 is connected to the deposition substrate 301.

[0157] (10) The coarse positioning system 2 drives the liquid container 1 to descend until the contact force sensor 202 senses that the force value is not 0N and stops. At this time, the liquid container 1 contacts the deposition substrate 301.

[0158] (11) The piezoelectric nano-precision positioning platform 302 drives the deposition substrate 301 to descend until the initial force mentioned above returns to zero, and then continues to descend by 10 nm as a reserved space for the initial metal layer deposition.

[0159] (12) Apply a DC voltage of 0.8V between the initial layer electrolyte and the conductive substrate for 10s to reduce the metal cations in the electrolyte diffused from the end of the microstructure array on the bottom surface of the liquid carrier 1 to metal elements. During the deposition process, the contact force sensor 202 monitors the contact force in real time and keeps it within the range of 3 to 5mN.

[0160] (13) The reduced single-layer copper element array is deposited on the deposition substrate 301, and the piezoelectric nanoprecision positioning platform 302 is lowered by 10 nm as a reserved space for the next layer of deposited metal. The above deposition process is repeated.

[0161] Comparative Example 2: The effect of PDMS crosslinking degree on self-diffusion rate (high crosslinking degree)

[0162] (1) Dow Corning Sylgard TM 184 substrate, curing agent, PDMS-b-PEO (PEO branch molecular weight of 600) were formulated in a mass ratio of 100:10:1 to prepare a hydrophilically modified low crosslinking silicone rubber fluid material.

[0163] (2) A silicon wafer template with a micro-needle tip concave hole array on the surface is processed using high-precision laser etching silicon wafer technology. The concave holes are frustum-shaped, with a bottom diameter of 10μm, a top diameter of 20μm, and a depth of 30μm. The array is a rectangular array with an array spacing of 50μm.

[0164] (3) A liquid storage cavity mold was manufactured using photopolymerization 3D printing technology. The mold has an inner diameter of 10 mm and a height of 10 mm.

[0165] (4) Place the liquid storage cavity mold above the microneedle tip silicon wafer template prepared in step (2) and press it down. Inject the silicone rubber fluid material prepared in step (1) from the pouring port at the top of the liquid storage cavity mold to fill the microneedle tip concave hole array and the entire liquid storage cavity mold cavity.

[0166] (5) Place the above template, mold, and silicone rubber in an oven, set the temperature to 120°C, and keep it for 2 hours to allow the silicone rubber to complete vulcanization and maintain its shape. Then remove the mold and template to complete the preparation of the silicone rubber microneedle tip stamp.

[0167] (7) Place the prepared silicone rubber microneedle tip stamp in 200ml of ethyl acetate liquid and clean it with ultrasonic vibration for 20 minutes to clean the thermosetting silicone rubber that has not been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules in some areas. Take out the silicone rubber microneedle tip stamp and rinse the remaining ethyl acetate liquid again with deionized water to obtain pore channels of 1nm to 100nm inside the silicone rubber material.

[0168] (8) Build a metal three-dimensional microstructure manufacturing equipment based on the self-diffusion mechanism of electrolyte in silicone rubber, install the silicone rubber microstructure liquid carrier 1 prepared in step (8) on the ion array equipment, use ITO peeling as the deposition substrate 301, and fix it on the piezoelectric nano displacement stage 302.

[0169] (9) Prepare a copper sulfate solution with a high concentration of copper ions of 207 g / L as electrolyte 7. Put the copper sulfate solution into a silicone rubber microstructure carrier container 1 as a constant mass transfer element. Insert a metal electrode 4 into the carrier container 1. The electrode 4 is connected to the positive terminal of the voltage source device 5 through the current monitoring device 6 of the electrochemical deposition system. The negative terminal of the voltage source device 5 is connected to the deposition substrate 301.

[0170] (10) The coarse positioning system 2 drives the liquid container 1 to descend until the contact force sensor 202 senses that the force value is not 0N and stops. At this time, the liquid container 1 contacts the deposition substrate 301.

[0171] (11) The piezoelectric nano-precision positioning platform 302 drives the deposition substrate 301 to descend until the initial force mentioned above returns to zero, and then continues to descend by 10 nm as a reserved space for the initial metal layer deposition.

[0172] (12) Apply a DC voltage of 0.8V between the initial layer electrolyte and the conductive substrate for 10s to reduce the metal cations in the electrolyte diffused from the end of the microstructure array on the bottom surface of the liquid carrier 1 to metal elements. During the deposition process, the contact force sensor 202 monitors the contact force in real time and keeps it within the range of 3 to 5mN.

[0173] (13) The reduced single-layer copper element array is deposited on the deposition substrate 301, and the piezoelectric nanoprecision positioning platform 302 is lowered by 10 nm as a reserved space for the next layer of deposited metal. The above deposition process is repeated.

[0174] Comparative Example 3: The effect of PDMS wettability on the self-diffusion rate (without PDMS-b-PEO)

[0175] (1) Dow Corning Sylgard TM 184 substrate and curing agent are mixed at a mass ratio of 100:5 to prepare a low-crosslinking silicone rubber fluid material;

[0176] (2) A silicon wafer template with a micro-needle tip concave hole array on the surface is processed using high-precision laser etching silicon wafer technology. The concave holes are frustum-shaped, with a bottom diameter of 10μm, a top diameter of 20μm, and a depth of 30μm. The array is a rectangular array with an array spacing of 50μm.

[0177] (3) A liquid storage cavity mold was manufactured using photopolymerization 3D printing technology. The mold has an inner diameter of 10 mm and a height of 10 mm.

[0178] (4) Place the liquid storage cavity mold above the microneedle tip silicon wafer template prepared in step (2) and press it down. Inject the silicone rubber fluid material prepared in step (1) from the pouring port at the top of the liquid storage cavity mold to fill the microneedle tip concave hole array and the entire liquid storage cavity mold cavity.

[0179] (5) Place the above template, mold, and silicone rubber in an oven, set the temperature to 120°C, and keep it for 2 hours to allow the silicone rubber to complete vulcanization and maintain its shape. Then remove the mold and template to complete the preparation of the silicone rubber microneedle tip stamp.

[0180] (7) Place the prepared silicone rubber microneedle tip stamp in 200ml of ethyl acetate liquid and clean it with ultrasonic vibration for 20 minutes to clean the thermosetting silicone rubber that has not been fully cross-linked, thereby removing the uncross-linked silicone rubber molecules in some areas. Take out the silicone rubber microneedle tip stamp and rinse the remaining ethyl acetate liquid again with deionized water to obtain pore channels of 1nm to 100nm inside the silicone rubber material.

[0181] (8) Build a metal three-dimensional microstructure manufacturing equipment based on the self-diffusion mechanism of electrolyte in silicone rubber, install the silicone rubber microstructure liquid carrier 1 prepared in step (8) on the ion array equipment, use ITO peeling as the deposition substrate 301, and fix it on the piezoelectric nano displacement stage 302.

[0182] (9) Prepare a copper sulfate solution with a high concentration of copper ions of 207 g / L as electrolyte 7. Put the copper sulfate solution into a silicone rubber microstructure carrier container 1 as a constant mass transfer element. Insert a metal electrode 4 into the carrier container 1. The electrode 4 is connected to the positive terminal of the voltage source device 5 through the current monitoring device 6 of the electrochemical deposition system. The negative terminal of the voltage source device 5 is connected to the deposition substrate 301.

[0183] (10) The coarse positioning system 2 drives the liquid container 1 to descend until the contact force sensor 202 senses that the force value is not 0N and stops. At this time, the liquid container 1 contacts the deposition substrate 301.

[0184] (11) The piezoelectric nano-precision positioning platform 302 drives the deposition substrate 301 to descend until the initial force mentioned above returns to zero, and then continues to descend by 10 nm as a reserved space for the initial metal layer deposition.

[0185] (12) Apply a DC voltage of 0.8V between the initial layer electrolyte and the conductive substrate for 10s to reduce the metal cations in the electrolyte diffused from the end of the microstructure array on the bottom surface of the liquid carrier 1 to metal elements. During the deposition process, the contact force sensor 202 monitors the contact force in real time and keeps it within the range of 3 to 5mN.

[0186] (13) The reduced single-layer copper element array is deposited on the deposition substrate 301, and the piezoelectric nanoprecision positioning platform 302 is lowered by 10 nm as a reserved space for the next layer of deposited metal. The above deposition process is repeated.

[0187] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A method for preparing a liquid-carrying container, characterized in that, Includes the following steps: A template (9) with an array of microneedle-shaped recesses on its surface was prepared. The liquid storage cavity mold (8) is fixed on the template (9) of the concave hole array. Silicone rubber material is injected into the liquid storage cavity mold (8). After heating and curing, the liquid carrier (1) with microneedles (101) made of silicone rubber is obtained by demolding. Micro-nano pores are formed inside the liquid carrier (1) and the microneedle (101). The electrolyte (7) contained in the liquid carrier cavity (102) of the liquid carrier (1) flows out from the pores of the micro-nano pores. The pore size of the micro-nano pores ranges from 1 nm to 100 nm. During the molding process of the liquid carrier (1), micro-nano pores are formed in the silicone rubber material by using an organic solvent cleaning method; The silicone rubber material is Dow Corning SYLGARD™ 184 substrate, curing agent, and PDMS-b-PEO in a mass ratio of 100:5:

1.

2. The method for preparing the liquid-carrying container as described in claim 1, characterized in that, The specific steps of the organic solvent cleaning method are as follows: Solvents are used to pre-clean thermosetting silicone rubber that is not fully cross-linked, removing local uncross-linked silicone rubber molecules and forming micro-nano porous channels.

3. A method for preparing metal microstructures with nanolayer thickness deposition precision, characterized in that, The process includes the following steps: injecting electrolyte (7) into the liquid carrier (1) of the preparation device. The liquid carrier (1) is prepared by the liquid carrier preparation method described in claim 1. The electrolyte (7) is a metal ion solution. The metal ion solution is released by self-diffusion through the micro-nano pores of the liquid carrier (1) under the condition of the concentration difference between its own concentration and the external concentration. The diffused metal ion solution forms an electrolyte layer with a thickness of less than 10 nm on the deposition substrate (301) of the preparation device. The electrolyte layer and the deposition substrate (301) conduct electricity and a DC voltage is applied. During this process, the metal cations in the electrolyte (7) diffuse out from the tip of the microneedle (101) of the liquid carrier (1) and are reduced to metal elements. The reduced single-layer metal element is deposited on the deposition substrate (301). The preparation equipment drives the deposition substrate (301) to descend a predetermined distance, which serves as a reserved space for the next layer of metal deposition, until the metal three-dimensional microstructure is stacked on the deposition substrate (301). Throughout the above process, the contact force between the liquid carrier container (1) and the deposition substrate (301) is maintained. The electrolyte (7) is a copper sulfate solution of 207 g / L or a silver nitrate solution of 216 g / L.

4. The method for preparing metal microstructures with nanolayer thickness deposition precision as described in claim 3, characterized in that: The specific steps for establishing electrical conductivity between the electrolyte (7) layer and the deposition substrate (301) are as follows: The metal ion solution is poured into the liquid carrier container (1) as a constant mass transfer unit; A metal electrode (4) is inserted into the liquid-carrying chamber (102) of the liquid-carrying container (1). The metal electrode (4) is connected to the positive terminal of the external voltage source (5) device, and the negative terminal of the voltage source (5) device is connected to the deposition substrate (301). When the microneedles (101) of the liquid carrier (1) come into contact with the deposition substrate (301), this closed-loop circuit is turned on, forming an electrochemical deposition system.

5. A fabrication apparatus used in a method for fabricating a metal microstructure with nanolayer thickness deposition precision as described in claim 3, characterized in that: Including a coarse positioning system (2) and a fine positioning system (3), The coarse positioning system (2) includes: An electrically driven slide (201) is mounted on a plane, and a liquid container (1) is installed on the electrically driven slide (201). A contact force sensor (202) is slidably connected to the electric drive slide (201). The contact force sensor (202) maintains a monitoring state during the movement of the electric drive slide (201). The precise positioning system (3) includes: The piezoelectric nanostage (302) is located on the plane of the electrically driven slide (201) and below the liquid container (1) on the electrically driven slide (201). The deposition substrate (301) is slidably connected to the piezoelectric nano-displacement stage (302), and the metal ion solution diffused from the liquid container (1) falls onto the deposition substrate (301).

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