Silver wire processing method based on laser direct writing system and silver wire

Abstract

The invention provides a silver wire based on a laser direct writing system and a processing method thereof. The processing method comprises the following steps: coating a mixed solution of a silver compound and a polymer on a substrate to form a precursor film; the precursor film is subjected to an in-situ photochemical or photo-thermal chemical reaction through laser emitted by a laser direct writing system, the silver wire is obtained, and the in-situ photochemical or photo-thermal chemical reaction comprises the steps that polymer is removed, and a silver compound is reduced into silver. The laser direct writing system focuses laser, high-energy micro-spots are formed after focusing, the high-energy micro-spots induce a photo-thermal or photochemical reaction due to the fact that the sizes of the high-energy micro-spots are micron-sized and submicron-sized, and silver compounds are reduced into micron-sized and submicron-sized silver wires.

Description

Technical Field

[0001] The invention relates to the field of preparation of silver wires, and in particular to a silver wire processing method based on a laser direct writing system and the silver wire. Background Art

[0002] Flexible hybrid electronics adopts a strategy of combining "soft" and "hard", combining traditional "hard" and small high-performance silicon-based electronic devices with "soft" and flexible low-cost electronic devices to obtain wearable flexible hybrid electronic devices. In order to achieve high integration of devices, the connecting wires between the "soft" and "hard" components need to have high conductivity, narrow line width, flexibility, high adhesion and other properties, especially the line width should be within 5 microns.

[0003] In the prior art, there are three methods to obtain silver wire:

[0004] First, conventional photolithography or electron beam etching uses high resolution of photon or electron exposure to etch to obtain silver wires with micron-level line width. Here, in order to obtain very high resolution, a proprietary photolithography machine or etching machine is required. However, proprietary photolithography machines or etching machines are expensive and costly, and are difficult to produce at low cost on flexible substrates due to high equipment requirements.

[0005] Second, the mask-combined chemical etching method uses photolithography or electron beam etching to produce a mask, combined with a chemical etching method, which can achieve template reuse. However, chemical etching uses corrosive solutions such as hydrofluoric acid and nitric acid, which will produce highly polluted wastewater and the material utilization rate of this method is low.

[0006] Third, printing or printing technology is to print the conductive paste directly onto the substrate. However, this requires high compatibility between the substrate surface and the conductive paste, and the subsequent heat treatment process may damage the polymer flexible substrate. In addition, the resolution of printing or printing technology is also limited by the nozzle, and it is difficult to achieve micron-level line width.

[0007] Therefore, it is necessary to develop a low-cost, environmentally friendly, substrate-safe processing method for micron- and submicron-level silver wires. Summary of the invention

[0008] The present invention aims to solve the problem in the prior art that it is difficult to process silver wires with micron and submicron line widths at low cost, in an environmentally friendly manner, and without damaging the substrate, and proposes a silver wire based on a laser direct writing system and a processing method thereof.

[0009] The technical method of the present invention is as follows:

[0010] A silver wire processing method based on a laser direct writing system, the processing method comprising: coating a mixed solution of a silver compound and a polymer on a substrate to form a precursor film; using laser light emitted by the laser direct writing system to cause an in-situ photochemical or photothermochemical reaction on the precursor film to obtain the silver wire, wherein the in-situ photochemical or photothermochemical reaction comprises: removing the polymer and reducing the silver compound to silver.

[0011] The step of emitting laser light through the laser direct writing system includes: constructing a laser direct writing system, wherein the laser direct writing system includes a laser, an optical path and an optical lens unit, and a sample motion platform; the laser light emitted by the laser passes through the optical path and the optical lens unit to obtain a focused light beam; and the precursor film is driven to move relative to the focused light beam through the sample motion platform.

[0012] The step of allowing the laser emitted by the laser to pass through an optical path and an optical lens unit comprises: constructing an optical path and an optical lens unit, wherein the optical path and the optical lens unit comprise an aperture, a filter, a reflector, and a focusing lens; adjusting the laser diameter of the laser emitted by the laser generator through the aperture; filtering the laser with the adjusted diameter through a filter; reflecting the filtered laser through a reflector; and focusing the reflected laser through a focusing lens to obtain a focused light beam.

[0013] The step of focusing includes: focusing the reflected laser light by using a lens focusing power of 5 to 100 times.

[0014] The laser is a continuous wave laser, the wavelength range of the laser is 193-1064nm, and the power of the laser is 30-5000mW; the speed of the sample motion platform is 0.1-500mm / s.

[0015] The silver compound includes an organic silver compound and / or an inorganic silver compound; wherein the inorganic silver compound includes one or more of silver nitrate, silver phosphate, silver fluoride, silver tetrafluoroborate, silver hexafluorophosphate, and silver perchlorate; the organic silver compound includes one or more of silver acetate, silver citrate, silver trifluoroacetate, silver acetylacetonate, silver cyclohexylbutyrate, silver benzoate, silver lactate, silver cyanate, silver salicylate, silver trifluoromethanesulfonate, silver thiocyanate, and silver methanesulfonate.

[0016] The polymer includes one or more of polyacrylamide, polyacrylic acid, polyvinyl pyrrolidone, polyvinyl alcohol, polymaleic anhydride, polyquaternium salt, polyethylene glycol, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, starch, gum arabic, sodium alginate, bone meal, gelatin, casein, polyaniline, polymethyl methacrylate, polyacrylonitrile, and phenolic resin.

[0017] The precursor film has a thickness of 0.01 to 50 μm.

[0018] The present invention also provides a silver wire, which is obtained by the silver wire processing method based on the laser direct writing system, and the line width of the silver wire is 0.5-50 μm.

[0019] The beneficial effects of the present invention are:

[0020] (1) First, the laser direct writing system used in the present invention is a non-contact, fast one-step preparation system that does not require masks, post-processing, and complex clean rooms, and has low cost. Second, compared with printing technology, the laser direct writing system adopts a fast line scanning method, which is a local interaction. Only the reaction occurs at the laser irradiation point, which effectively avoids the influence of overall heat treatment and is suitable for any substrate. At the same time, by adjusting the laser wavelength, laser power and other parameters, it can achieve no damage to the substrate. The thermal effect of laser direct writing also makes the interface bonding stronger, which is conducive to enhancing mechanical stability. Third, the laser direct writing system focuses the laser to form high-energy micro spots after focusing. Since the size of the high-energy micro spots is in the micron and submicron levels, the high-energy micro spots induce photothermal or photochemical reactions to reduce the silver compound to micron and submicron silver wires. Fourth, by adjusting the precursor film thickness, silver compound content, laser power, sample motion platform speed, and focusing multiple, the silver wire width, conductivity and production efficiency can be adjusted very conveniently and pollution-free. It has great flexibility and can match the product requirements of different scenarios.

[0021] (1) The present invention can be integrated with the roll-to-roll process to achieve batch and automated production.

[0022] (2) The silver compound and polymer used in the present invention are both mature chemical industrial products with low cost and no complicated production and processing process.

[0023] (3) The laser light source used in the present invention is a continuous wave laser with adjustable wavelength, low cost and easy integration.

[0024] (4) The present invention uses an optical unit to focus the laser to obtain high resolution and high energy density, so that the silver compound irradiated by the laser reacts with the polymer to generate dense silver wires.

[0025] (5) The present invention can be used to process silver wires of the micron and submicron order, for example, silver wires of 0.5 to 50 μm in width, thereby combining traditional “hard” and small high-performance silicon-based electronic devices with “soft” and flexible low-cost electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Process flow chart for preparing silver wire for laser direct writing;

[0027] Figure 2is the relationship between the silver line width and the laser power and scanning speed;

[0028] Figure 3 This is a graph showing the relationship between the resistance of the silver wire and the laser power and scanning speed. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The concept of the present invention is: the present invention adopts a laser direct writing system and two materials to prepare a high-conductivity, high-resolution silver wire to solve the problems of high cost, high pollution and damage to the substrate in the existing process.

[0031] The present invention provides a silver wire processing method based on a laser direct writing system, the processing method comprising:

[0032] S1. Apply a mixed solution of a silver compound and a polymer on a substrate to form a precursor film.

[0033] Specifically, the silver compound includes an organic silver compound and / or an inorganic silver compound; wherein the inorganic silver compound includes one or more of silver nitrate, silver phosphate, silver fluoride, silver tetrafluoroborate, silver hexafluorophosphate, and silver perchlorate; the organic silver compound includes one or more of silver acetate, silver citrate, silver trifluoroacetate, silver acetylacetonate, silver cyclohexylbutyrate, silver benzoate, silver lactate, silver cyanate, silver salicylate, silver trifluoromethanesulfonate, silver thiocyanate, and silver methanesulfonate. Preferably, the silver compound may be silver nitrate.

[0034] Specifically, the polymer includes one or more of polyacrylamide, polyacrylic acid, polyvinyl pyrrolidone (PVP), polyvinyl alcohol, polymaleic anhydride, polyquaternium salt, polyethylene glycol, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, starch, gum arabic, sodium alginate, bone meal, gelatin, casein, polyaniline, polymethyl methacrylate, polyacrylonitrile, and phenolic resin. Preferably, the polymer can be polyvinyl pyrrolidone or polyethylene glycol.

[0035] The silver compound and the polymer can be mixed by ultrasound for 20 to 50 minutes. The ratio of the silver compound to the polymer can be 0.05 to 1:0.05 to 1.

[0036] Here, the polymer and / or the silver compound can also be mixed with a solvent for use. The solvent includes one or more of water, ethanol, toluene, acetone, methanol, and acetonitrile.

[0037] The present invention uses a polymer as a dispersant to evenly disperse the silver compound and to control the thickness of the precursor film, thereby regulating the thickness of the silver line. At the same time, the present invention only uses a polymer as a dispersant, does not require other additives, has a simpler composition, and is easier to control the laser direct writing line width.

[0038] The thickness of the precursor film of the present invention is 0.01-50 μm, preferably 1 μm. Meanwhile, different precursor films can use different silver compounds and polymers.

[0039] The mixed solution of the silver compound and the polymer is spin-coated, drip-coated, spray-coated, pulled, scraped, or coated to form a precursor film on the surface of the substrate. The spin coating method is preferred. Compared with the direct coating method, the spin coating method can be used to control the thickness of the precursor film, which can be adjusted more finely and can obtain an ultra-thin thickness of less than 1 μm. Ultra-thin and ultra-fine silver wires (silver wire thickness less than 100 nm and width less than 5 μm) can be obtained by laser direct writing.

[0040] The substrate of the present invention may be a flexible substrate, such as one or more of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl alcohol (PVA), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyimide (PI), and polyurethane (PU).

[0041] S2. The laser emitted by the laser direct writing system causes an in-situ photochemical or photothermochemical reaction on the precursor film to obtain a silver wire, wherein the in-situ photochemical or photothermochemical reaction includes: removing the polymer and reducing the silver compound to silver. Here, in the in-situ photochemical reaction, the silver compound undergoes a reduction reaction under the action of the polymer to generate a silver wire. In the photothermochemical reaction, the polymer decomposes and reacts chemically with oxygen in the air and is removed simultaneously. In the present invention, the steps of emitting laser light by the laser direct writing system include:

[0042] A1. Construct a laser direct writing system, wherein the laser direct writing system includes a laser, an optical path and an optical lens unit, and a sample motion platform.

[0043] Specifically, the laser emitted by the laser passes through the optical path and optical lens unit, including: constructing the optical path and optical lens unit, wherein the optical path and optical lens unit include an aperture, a filter, a reflector, and a focusing lens. Here, in the laser direct writing system, the aperture controls the light flux entering the optical system by limiting the beam diameter, reduces stray light to improve the imaging resolution and signal-to-noise ratio, and ensures accurate and stable writing. The filter can select a laser of a specific wavelength, adjust the light intensity, and shape the beam so that the laser wavelength, intensity, and beam shape meet the processing requirements. The reflector is responsible for changing the propagation direction of the laser and guiding the beam to the specified area. Some curved reflectors can also focus the beam, increase the energy density, or shape the beam, optimize the spot shape and divergence angle, and improve the writing resolution and accuracy. These three parts in the laser direct writing device will affect the final laser focus spot, thereby affecting the reaction. The focusing lens is used to focus the laser. When the size of the focus spot is micron and submicron, the generated silver wire will also be micro-nano and submicron.

[0044] Specifically, the number of reflectors can be multiple, which are used for multiple reflections to enhance the coherence and stability of light and achieve laser amplification and stable output. For example, the number of reflectors is 3, and when the laser is located at the bottom of the reflector, the laser enters the reflector above the focusing lens after being reflected twice.

[0045] Specifically, the laser emitted by the laser generator is adjusted through an aperture to adjust the laser diameter; the laser with adjusted diameter is filtered through a filter; the filtered laser is reflected through a reflector; the reflected laser enters a focusing lens for focusing to obtain a focused beam. Here, the laser is focused using a corresponding optical path and a focusing lens as needed to obtain high resolution and high energy density, so that the precursor irradiated by the laser reacts to generate dense silver wires.

[0046] Specifically, the focusing step includes: the focusing lens adjusts the focal length to focus the reflected laser through a 5-100 times focusing lens. The optical path system and the optical lens are crucial to the silver line resolution, and the focusing lens magnification is 5-100 times. The focusing lens magnification is preferably 50 times.

[0047] A2. The laser emitted by the laser passes through the optical path and the optical lens unit to obtain a focused beam; the precursor film is driven to move relative to the focused beam through the sample motion platform.

[0048] Optionally, lasers have been widely used in industry for material welding, cutting, polishing, marking, etc., and their wavelength and power can be adjusted over a wide range, and can be compatible with existing production lines for industrial production. The laser is a continuous wave laser with adjustable wavelength, low cost and easy integration. The wavelength range of the laser is 193-1064nm, preferably 405nm. For example, within the range of 193-1064nm, a smaller diffraction limit can be obtained, while silver nitrate efficiently absorbs laser energy and undergoes a reduction reaction. The power of the laser is 30-5000mW, preferably 60mW. The speed of the motion platform is 0.1-500mm / s, preferably 3mm / s. Here, the speed of the sample motion platform, the laser power and the focusing lens multiple will affect the silver line width.

[0049] In one embodiment, the laser direct writing system further comprises a computer control system, which uses a computer control program to control the movement of the sample motion platform to generate a corresponding laser irradiation path, thereby obtaining a silver line.

[0050] Specifically, the process flow chart of the laser direct writing method for preparing silver wires used in the present invention is as follows: Figure 1 As shown. After the surface of any substrate is cleaned, a mixed solution of a silver compound (silver nitrate) and a polymer (PVP) is spin-coated, drip-coated, spray-coated, pulled, scraped or coated on the surface of the substrate to form a precursor film, and the film is placed in a laser direct writing system for laser irradiation, and a specific pattern is completed through a control program. The laser irradiated part undergoes a photochemical or photothermochemical reaction to form a silver wire fused with silver particles, and the remaining part is cleaned with a solvent to obtain a substrate with a specific silver wire pattern. The cleaning solution can be reused as a precursor solution after being quantified or fixed in volume, and there is no material loss in the entire process. Here, the silver wire particle size is 5 to 200 nm. The line width of the silver wire is 0.5 to 50 μm. It should be noted that the present invention can also use this method to prepare zero-dimensional silver dots and two-dimensional silver surfaces.

[0051] The present invention also provides a silver wire based on a laser direct writing system, the silver wire is obtained by the silver wire processing method based on a laser direct writing system, and the line width of the silver wire is 0.5 to 50 μm. For example, the line width of the silver wire can be 1 to 5 μm.

[0052] The present invention is further described in detail below by taking the specific application of the method of the present invention in silver wire as an example.

[0053] Example 1

[0054] A silver wire processing method based on a laser direct writing system, comprising:

[0055] Step 1: Prepare a silver precursor solution by mixing 1 g / ml silver nitrate aqueous solution and 0.1 g / ml PVP aqueous solution in a ratio of 1:1, ultrasonicate the prepared precursor mixture for 30 minutes, then drop 0.1 ml of the precursor solution on a 1.5 cm × 1.5 cm substrate, and spin coat it on a coater at 1500 RPM for 200 seconds to obtain a silver precursor film.

[0056] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0057] Step 3: The 60mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0058] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain 5 ± 0.3 μm silver wire.

[0059] Example 2

[0060] A silver wire processing method based on a laser direct writing system, comprising:

[0061] Step 1: Prepare a silver precursor solution by mixing 1 g / ml silver nitrate aqueous solution and 0.1 g / ml gum arabic aqueous solution in a ratio of 1:1, ultrasonicate the prepared silver precursor mixture for 30 minutes, then drop 0.1 ml of the precursor solution on a 1.5 cm×1.5 cm substrate, and spin coat it on a coater at 1500 RPM for 200 seconds to obtain a silver precursor film.

[0062] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0063] Step 3: The 84.5mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0064] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain 8.5 ± 0.3 μm silver wire.

[0065] Example 3

[0066] A silver wire processing method based on a laser direct writing system, comprising:

[0067] Step 1: Weigh 1g of silver acetate and put it into 1ml of ethanol solution, dissolve it at high temperature to obtain 1g / ml silver acetate ethanol solution. Prepare 0.1g / ml gum arabic aqueous solution. Mix the prepared silver acetate ethanol solution and gum arabic aqueous solution in a ratio of 1:1 to obtain a silver precursor solution, then ultrasonicate the silver precursor mixture for 30 minutes, then take 0.1ml of the precursor solution and drop it on a 1.5cm×1.5cm substrate, and spin coat it on a coating machine at 1500RPM for 200s to obtain a silver precursor film.

[0068] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0069] Step 3: The 60mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0070] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 6 μm silver wire.

[0071] Example 4

[0072] A silver wire processing method based on a laser direct writing system, comprising:

[0073] Step 1: Weigh 1g of silver acetate and put it into 1ml of ethanol solution, dissolve it at high temperature to obtain 1g / ml silver acetate ethanol solution. Prepare 0.1g / ml PVP aqueous solution. Ultrasonicate the silver precursor mixture for 30 minutes, then mix the prepared silver acetate ethanol solution and PVP aqueous solution in a ratio of 1:1 to obtain a silver precursor solution. Ultrasonicate the mixture for 30 minutes, then take 0.1ml of the precursor solution and drop it on a 1.5cm×1.5cm substrate, and spin coat it at 1500RPM for 200s on a coating machine to obtain a silver precursor film.

[0074] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0075] Step 3: The 84.5mW laser emitted by the laser passes through the aperture, filter, reflector, and 10x focusing lens in sequence to obtain a focused beam;

[0076] Step 4: Set the speed of the motion platform to 1 mm / s, driving the precursor film to move relative to the focused beam to obtain a 24 μm silver wire.

[0077] Example 5

[0078] A silver wire processing method based on a laser direct writing system, comprising:

[0079] Step 1: Weigh 1g of polyethylene glycol powder and silver nitrate and dissolve them in 1ml of deionized water to obtain 1g / ml polyethylene glycol aqueous solution and 1g / ml silver nitrate aqueous solution. Mix the two solutions in a ratio of 1:1 and put them into an ultrasonic machine for 30 minutes to obtain a silver precursor mixed solution. Take 1ml of the mixed solution and drop it on a 1.5cm×1.5cm substrate, and spin coat it at 1000RPM for 200s to obtain a silver precursor film.

[0080] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0081] Step 3: The 84.5mW laser emitted by the laser passes through the aperture, filter, reflector, and 20x focusing lens in sequence to obtain a focused beam;

[0082] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 12 μm silver wire.

[0083] Example 6

[0084] A silver wire processing method based on a laser direct writing system, comprising:

[0085] Step 1: Prepare 1g / ml polyvinyl alcohol aqueous solution and 0.2g / ml silver nitrate aqueous solution in a ratio of 1:1 and put them into an ultrasonic machine for 30 minutes of ultrasonic treatment. Then take 0.2ml of the precursor solution and drop it on a 2cm×2cm substrate and place it in a fume hood to dry. A 2cm×2cm silver precursor film is obtained. Finally, use scissors to cut the middle part to obtain a 1.5×1.5 relatively uniform film.

[0086] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0087] Step 3: The 60mW laser emitted by the laser passes through the aperture, filter, reflector, and 100x focusing lens in sequence to obtain a focused beam;

[0088] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 1.2 μm silver wire.

[0089] Example 7

[0090] A silver wire processing method based on a laser direct writing system, comprising:

[0091] Step 1: Weigh 0.2g of silver acetate and put it into 1ml of ethanol solution, dissolve it at high temperature to obtain 0.2g / ml silver acetate ethanol solution. Weigh 0.5g of polyvinyl alcohol and dissolve it in 1ml of deionized water to obtain 0.5g / ml polyvinyl alcohol aqueous solution. Mix the two solutions in a ratio of 1:1 and then ultrasonically treat for 30min. Immerse a 1.5cm×1.5cm substrate in a container with the prepared silver precursor solution, repeat several times, and put it in an oven for low-temperature drying to obtain a silver precursor film.

[0092] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0093] Step 3: The 60mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0094] Step 4: Set the speed of the motion platform to 1 mm / s, driving the precursor film to move relative to the focused beam to obtain a 10 μm silver wire.

[0095] Example 8

[0096] A silver wire processing method based on a laser direct writing system, comprising:

[0097] Step 1: Dissolve 0.2g of silver nitrate in 10ml of deionized water, shake the reagent bottle to fully dissolve the silver nitrate in the bottle. Add 0.2g of gelatin to the solution, stir in a 70℃ water bath until the gelatin is fully dissolved. Then use a pipette to take 0.1ml of the prepared solution and drop it on a 1.5×1.5 substrate, and cool it to room temperature to form a gelatin matrix with silver ions.

[0098] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0099] Step 3: The 104mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0100] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 9 μm silver wire.

[0101] Example 9

[0102] A silver wire processing method based on a laser direct writing system, comprising:

[0103] Step 1: Dissolve 1g of silver nitrate in 1ml of deionized water, shake the reagent bottle to fully dissolve the silver nitrate in the bottle. Add 0.02g of gelatin to the solution, and stir in a 70°C water bath until the gelatin is fully dissolved. Then use a pipette to take 0.1ml of the prepared solution and drop it on a 1.5cm×1.5cm substrate, and use a gelator to spin coat at 2000RPM for 200s to obtain a gel film with silver ions.

[0104] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0105] Step 3: The 60mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0106] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 4 μm silver wire.

[0107] Example 10

[0108] A silver wire processing method based on a laser direct writing system, comprising:

[0109] Step 1: Dissolve 1g of silver fluoride in 1ml of deionized water at room temperature to obtain a 1g / ml silver fluoride aqueous solution, take 0.5g of PVP with a large relative molecular weight and put it into a small beaker filled with 5ml of deionized water, place it on a magnetic stirrer to fully dissolve, and after the PVP in the beaker is fully dissolved, take 0.5g of PVP and put it into it and continue stirring. After the dissolution is complete, a 0.2g / ml PVP aqueous solution is obtained. Take 1ml of the PVP aqueous solution and slowly drip it into the silver fluoride aqueous solution, shake the reagent bottle to fully mix the two solutions. Take 0.1ml of the precursor solution and drop it on a 1.5cm×1.5cm substrate, and spin coat it on a gel coater at 1500RPM for 200s to obtain a silver precursor film.

[0110] Step 2: Fix the prepared silver precursor film on the sample motion platform;

[0111] Step 3: The 84.5mW laser emitted by the laser passes through the aperture, filter, reflector, and 50x focusing lens in sequence to obtain a focused beam;

[0112] Step 4: Set the speed of the motion platform to 3 mm / s, driving the precursor film to move relative to the focused beam to obtain a 7 μm silver wire.

[0113] like Figure 2 and Figure 3As shown, a silver precursor film is prepared by step 1 of Example 1, and a data comparison chart of the line width and resistance of the silver wire prepared at different scanning speeds and different powers is shown. It can be seen that when the power is in the range of 60 to 140 mW, the line width of the silver wire is 4 to 12 μm.

[0114] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A silver wire processing method based on a laser direct writing system, characterized in that: The processing method comprises: coating a mixed solution of a silver compound and a polymer on a substrate to form a precursor film; The laser emitted by the laser direct writing system causes an in-situ photochemical or photothermochemical reaction on the precursor film to obtain a silver conductor, wherein the in-situ photochemical or photothermochemical reaction includes: removing the polymer and reducing the silver compound to silver.

2. The processing method according to claim 1, characterized in that: The step of emitting laser light through the laser direct writing system comprises: Constructing a laser direct writing system, wherein the laser direct writing system includes a laser, an optical path and an optical lens unit, and a sample motion platform; The laser light emitted by the laser passes through the optical path and the optical lens unit to obtain a focused beam; The precursor film is moved relative to the focused light beam by the sample motion platform.

3. The processing method according to claim 2, characterized in that: The steps of the laser emitted by the laser passing through the optical path and the optical lens unit include: Constructing an optical path and an optical lens unit, wherein the optical path and the optical lens unit include an aperture, a filter, a reflector, and a focusing lens; The laser emitted by the laser generator adjusts the laser diameter through the aperture; The laser beam after adjusting the diameter is filtered through a filter; reflecting the filtered laser light through a mirror; The reflected laser enters the focusing lens for focusing to obtain a focused beam.

4. The processing method according to claim 3, characterized in that: The focusing step comprises: The reflected laser is focused using a 5 to 100 times lens.

5. The processing method according to claim 2, characterized in that: The laser is a continuous wave laser, the wavelength range of the laser is 193-1064nm, and the power of the laser is 30-5000mW; The speed of the motion platform is 0.1-500 mm / s.

6. The processing method according to claim 1, characterized in that: The silver compound includes an organic silver compound and / or an inorganic silver compound; wherein, The inorganic silver compound includes one or more of silver nitrate, silver phosphate, silver fluoride, silver tetrafluoroborate, silver hexafluorophosphate, and silver perchlorate; The organic silver compound includes one or more of silver acetate, silver citrate, silver trifluoroacetate, silver acetylacetonate, silver cyclohexylbutyrate, silver benzoate, silver lactate, silver cyanate, silver salicylate, silver trifluoromethanesulfonate, silver thiocyanate, and silver methanesulfonate.

7. The processing method according to claim 1, characterized in that: The polymer includes one or more of polyacrylamide, polyacrylic acid, polyvinyl pyrrolidone, polyvinyl alcohol, polymaleic anhydride, polyquaternium salt, polyethylene glycol, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, starch, gum arabic, sodium alginate, bone meal, gelatin, casein, polyaniline, polymethyl methacrylate, polyacrylonitrile, and phenolic resin.

8. The processing method according to claim 1, characterized in that: The precursor film has a thickness of 0.01 to 50 μm.

9. A silver wire, characterized in that: The silver wire is obtained by the silver wire processing method based on a laser direct writing system according to claims 1 to 8, and the line width of the silver wire is 0.5 to 50 μm.

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