Silver etching solution, preparation method and application thereof
By optimizing the silver etching solution formula and adding components such as polyethylene glycol-modified siloxane and benzotriazole derivatives, the problems of silver residue and aluminum damage in OLED manufacturing were solved, resulting in a more stable etching process and a longer service life, while reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI SHUNAO ENVIROMENTAL TECH CO LTD
- Filing Date
- 2026-03-08
- Publication Date
- 2026-06-05
AI Technical Summary
Existing silver etching solutions have problems such as silver residue, aluminum damage, and short lifespan in OLED manufacturing, which affect device performance and production costs.
A silver etching solution formulation is used, which includes phosphoric acid, nitric acid, acetic acid, organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor and etching conditioner. By adding polyethylene glycol modified siloxane as surfactant, benzotriazole derivative as corrosion inhibitor and etching conditioner to control etching rate, form protective film and reduce silver residue and aluminum corrosion.
It significantly reduces silver residue and aluminum damage, improves etching uniformity and stability, extends the service life of the etching solution, and reduces production costs.
Abstract
Description
Technical Field
[0001] This application relates to the field of etching technology, and more specifically, to a silver etching solution, its preparation method, and its application. Background Technology
[0002] With the rapid development of display technology, Organic Light Emitting Diodes (OLEDs) have become one of the mainstream technologies in the flat panel display field due to their advantages such as self-illumination, high contrast, and flexibility. In the manufacturing process of OLED devices, silver film is often used as an anode or cathode material due to its excellent conductivity and reflectivity. Wet etching is a crucial step in patterning the silver film, and its quality directly affects the performance and yield of the device.
[0003] Currently, commonly used silver etching solutions mainly consist of phosphoric acid, nitric acid, and acetic acid, achieving etching through the dissolution of silver by strong acids. However, this type of etching solution has several problems in practical applications: First, silver residue is easily generated during the etching process, leading to short circuits or unstable performance; second, the etching solution corrodes the underlying aluminum signal lines, causing variations in aluminum linewidth and affecting signal transmission quality; furthermore, traditional etching solutions have a short lifespan, and as the etching reaction proceeds, the increased silver ion concentration leads to unstable etching rates, affecting product consistency.
[0004] An existing silver etching solution comprises the following components by mass percentage: 55-60% phosphoric acid, 5-10% nitric acid, 10-15% acetic acid, 5-8% hydroxyl-containing carboxylic acid, 0.5-1% inorganic salt, 0.1-0.3% polyethylene glycol-functionalized thioctic acid polymer, 1-3% viscosity reducer, and the balance being water. By adding the polyethylene glycol-functionalized thioctic acid polymer, whose thioctic acid (LA) contains disulfide bonds, a monomolecular self-assembled film can be formed on the aluminum surface through disulfide bond interactions, constituting a dense nano-etching barrier layer that effectively isolates the silver etching solution and prevents damage to the aluminum. Furthermore, the disulfide bonds in the polyethylene glycol-functionalized thioctic acid polymer can coordinate with silver ions, suppressing the etching characteristic fluctuations caused by increased silver ion concentration and stabilizing the etching effect. However, this etching solution still cannot effectively solve the problems of silver residue and aluminum damage during long-term use, especially with the increase in the number of sheets processed, the etching performance significantly decreases.
[0005] Therefore, developing a silver etching solution that can effectively reduce silver residue, prevent aluminum layer damage, and has a long service life is of great significance for improving the quality of OLED display devices and reducing production costs. Summary of the Invention
[0006] The purpose of this invention is to provide a silver etching solution, its preparation method and application, which effectively solves the problems of silver residue, aluminum damage and short service life in the prior art.
[0007] In a first aspect, this application provides a silver etching solution, comprising, by weight percentage:
[0008] The composition includes 50-65% phosphoric acid, 3-12% nitric acid, 8-18% acetic acid, 4-10% organic acid complexing agent, 0.5-2% inorganic salt, 0.05-0.5% surfactant, 0.1-1% corrosion inhibitor, 0.5-3% etching conditioner, and the balance being water; wherein the surfactant is polyethylene glycol modified siloxane.
[0009] Preferably, the silver etching solution comprises, by weight percentage:
[0010] Phosphoric acid 55-62%, nitric acid 5-10%, acetic acid 10-15%, organic acid complexing agent 6-8%, inorganic salt 0.8-1.5%, surfactant 0.1-0.3%, corrosion inhibitor 0.3-0.7%, etching conditioner 1-2%, balance being water.
[0011] More preferably, the silver etching solution comprises, by weight percentage:
[0012] The composition is as follows: 58% phosphoric acid, 8% nitric acid, 12% acetic acid, 7% organic acid complexing agent, 1.2% inorganic salt, 0.2% surfactant, 0.5% corrosion inhibitor, 1.5% etching conditioner, and the balance is water.
[0013] Furthermore, the polyethylene glycol-modified siloxane has the general structural formula: Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3, where a takes the value of 5~15, b takes the value of 3~8, and n takes the value of 10~30.
[0014] Furthermore, the preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and catalyst chloroplatinic acid are added to a reactor, and toluene is used as a solvent. The reaction is carried out at 80~110°C for 6~12 hours. After the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0015] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5~2.5;
[0016] The amount of catalyst used is 50-100 ppm of the total mass of the reactants.
[0017] Furthermore, the corrosion inhibitor is a benzotriazole derivative.
[0018] Further, the corrosion inhibitor is one or more of 5-methylbenzotriazole, 5-carboxybenzotriazole, and 1-hydroxybenzotriazole.
[0019] Furthermore, the etching modifier is one or more of polyacrylamide, polyvinylpyrrolidone, and polyoxyethylene ether.
[0020] Furthermore, the organic acid complexing agent is one or more of citric acid, tartaric acid, oxalic acid, malic acid, and gluconic acid.
[0021] Furthermore, the inorganic salt is one or more of sodium nitrate, potassium nitrate, ammonium nitrate, sodium sulfate, and potassium sulfate.
[0022] Secondly, this application provides a method for preparing the silver etching solution according to any of the first aspects, comprising the following steps:
[0023] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0024] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 0.5 to 2 hours, and then filtered to obtain silver etching solution.
[0025] Thirdly, this application provides the application of any of the silver etching solutions described in the first aspect in flat panel OLED displays.
[0026] In summary, this application has the following beneficial effects:
[0027] 1. The silver etching solution of the present invention significantly reduces the surface tension of the etching solution and improves the etching uniformity by adding polyethylene glycol modified siloxane as a surfactant. At the same time, its siloxane structure can form a protective layer on the aluminum surface, effectively reducing the erosion of aluminum signal lines.
[0028] 2. This invention uses benzotriazole derivatives as corrosion inhibitors, which work synergistically with surfactants to form a denser protective film on the surfaces of silver and aluminum, significantly improving the protection effect on non-target metals without affecting the normal etching of silver.
[0029] 3. By adding an etching regulator, this invention effectively controls the etching rate, improves the stability of the etching process, and prevents lateral corrosion and silver residue problems caused by excessively fast etching.
[0030] 4. The synergistic effect of the components of the silver etching solution of the present invention not only effectively solves the problems of silver residue and aluminum damage, but also significantly extends the service life of the etching solution. It can maintain stable etching performance even after the number of sheets processed increases, thereby reducing production costs. Detailed Implementation
[0031] The technical solutions and effects of this application will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely for explaining the invention and are not intended to limit the invention.
[0032] Example 1
[0033] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0034] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0035] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0036] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0037] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0038] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0039] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0040] The etching modifier is polyacrylamide.
[0041] The organic acid complexing agent is citric acid.
[0042] The inorganic salt is sodium nitrate.
[0043] The method for preparing the silver etching solution includes the following steps:
[0044] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0045] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0046] Example 2
[0047] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0048] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0049] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0050] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 95°C for 8 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0051] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:2;
[0052] The amount of catalyst used is 75 ppm of the total mass of the reactants.
[0053] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0054] The etching modifier is polyacrylamide.
[0055] The organic acid complexing agent is citric acid.
[0056] The inorganic salt is sodium nitrate.
[0057] The method for preparing the silver etching solution includes the following steps:
[0058] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0059] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0060] Example 3
[0061] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0062] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0063] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0064] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, and toluene is used as solvent. The reaction is carried out at 110°C for 6 hours. After the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0065] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:2.5;
[0066] The amount of catalyst used is 100 ppm of the total mass of the reactants.
[0067] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0068] The etching modifier is polyacrylamide.
[0069] The organic acid complexing agent is citric acid.
[0070] The inorganic salt is sodium nitrate.
[0071] The method for preparing the silver etching solution includes the following steps:
[0072] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0073] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0074] Example 4
[0075] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0076] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0077] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0078] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0079] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0080] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0081] The corrosion inhibitor is a benzotriazole derivative, specifically a mixture of 5-methylbenzotriazole and 1-hydroxybenzotriazole, wherein the weight ratio of 5-methylbenzotriazole to 1-hydroxybenzotriazole is 1:0.3.
[0082] The etching modifier is polyacrylamide.
[0083] The organic acid complexing agent is citric acid.
[0084] The inorganic salt is sodium nitrate.
[0085] The method for preparing the silver etching solution includes the following steps:
[0086] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0087] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0088] Example 5
[0089] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0090] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0091] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0092] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0093] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0094] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0095] The corrosion inhibitor is a benzotriazole derivative, specifically a mixture of 5-methylbenzotriazole and 1-hydroxybenzotriazole, wherein the weight ratio of 5-methylbenzotriazole to 1-hydroxybenzotriazole is 1:0.6.
[0096] The etching modifier is polyacrylamide.
[0097] The organic acid complexing agent is citric acid.
[0098] The inorganic salt is sodium nitrate.
[0099] The method for preparing the silver etching solution includes the following steps:
[0100] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0101] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0102] Example 6
[0103] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0104] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0105] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0106] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0107] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0108] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0109] The corrosion inhibitor is a benzotriazole derivative, specifically a mixture of 5-methylbenzotriazole and 1-hydroxybenzotriazole, wherein the weight ratio of 5-methylbenzotriazole to 1-hydroxybenzotriazole is 1:0.8.
[0110] The etching modifier is polyacrylamide.
[0111] The organic acid complexing agent is citric acid.
[0112] The inorganic salt is sodium nitrate.
[0113] The method for preparing the silver etching solution includes the following steps:
[0114] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0115] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0116] Example 7
[0117] A silver etching solution comprises the following components by weight percentage: 50% phosphoric acid, 3% nitric acid, 8% acetic acid, 4% organic acid complexing agent, 0.5% inorganic salt, 0.05% surfactant, 0.1% etching inhibitor, 0.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0118] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0119] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0120] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0121] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0122] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0123] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0124] The etching modifier is a mixture of polyvinylpyrrolidone and polyoxyethylene ether, with a weight ratio of 1:1.4 between the two.
[0125] The organic acid complexing agent is oxalic acid.
[0126] The inorganic salt is a mixture of sodium sulfate and potassium sulfate, with a weight ratio of sodium sulfate to potassium sulfate of 1:1.
[0127] The method for preparing the silver etching solution includes the following steps:
[0128] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0129] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0130] Example 8
[0131] A silver etching solution comprises the following components by mass percentage: 55% phosphoric acid, 5% nitric acid, 10% acetic acid, 6% organic acid complexing agent, 0.8% inorganic salt, 0.1% surfactant, 0.3% etching inhibitor, 1% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0132] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0133] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0134] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0135] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0136] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0137] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0138] The etching modifier is polyacrylamide.
[0139] The organic acid complexing agent is citric acid.
[0140] The inorganic salt is sodium nitrate.
[0141] The method for preparing the silver etching solution includes the following steps:
[0142] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0143] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0144] Example 9
[0145] A silver etching solution comprises the following components by mass percentage: 58% phosphoric acid, 8% nitric acid, 12% acetic acid, 7% organic acid complexing agent, 1.2% inorganic salt, 0.2% surfactant, 0.5% etching inhibitor, 1.5% etching conditioner, and the balance being water. Polyethylene glycol modified siloxane, with the general structural formula:
[0146] Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3,
[0147] Where a takes values from 5 to 15, b takes values from 3 to 8, and n takes values from 10 to 30.
[0148] The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80°C for 12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane.
[0149] The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5;
[0150] The amount of catalyst used is 50 ppm of the total mass of the reactants.
[0151] The corrosion inhibitor is a benzotriazole derivative, specifically 5-methylbenzotriazole.
[0152] The etching modifier is polyacrylamide.
[0153] The organic acid complexing agent is citric acid.
[0154] The inorganic salt is sodium nitrate.
[0155] The method for preparing the silver etching solution includes the following steps:
[0156] Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid;
[0157] Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor, and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 1 hour, and the silver etching solution is obtained after filtration.
[0158] Comparative Example 1
[0159] Compared with Example 1, the only difference is that the surfactant polyethylene glycol modified siloxane is not added, while the other components and amounts are the same.
[0160] Comparative Example 2
[0161] Compared with Example 1, the only difference is that no corrosion inhibitor is added, while the other components and amounts are the same.
[0162] Comparative Example 3
[0163] Compared with Example 1, the only difference is that no etching modifier is added, while the other components and amounts are the same.
[0164] Comparative Example 4
[0165] The etching solution formulation used in the prior art comprises the following components by mass percentage: 58.5% phosphoric acid, 8% nitric acid, 13% acetic acid, 6.5% hydroxyl-containing carboxylic acid, 0.85% inorganic salt, 0.2% polyethylene glycol-functionalized thioctic acid polymer, 2% viscosity reducer, and the balance being water.
[0166] Performance testing:
[0167] At 40°C, OLED test samples with an ITO / Ag / ITO multilayer structure were immersed in the etching solutions of the respective examples and comparative examples for 60 seconds, then rinsed with ultrapure water for 1 minute and dried with nitrogen. Evaluation indicators included: degree of silver residue, degree of aluminum damage, and service life (expressed as the number of processed sheets before the etching performance began to decline significantly).
[0168] Evaluation of silver residue: The presence of silver residue was confirmed by scanning electron microscopy (SEM) in the area of residual metal film between the ITO / Ag / ITO wiring; Evaluation criteria:
[0169] None: No visible silver residue, residue area ratio <0.1%;
[0170] Small amount: Slight silver residue, with a residual area ratio of 0.1% to 1%;
[0171] Significant silver residue: The residue area ratio is >1%.
[0172] Aluminum Damage Assessment: The degree of aluminum damage was assessed using focused ion beam microscopy (FIB). Aluminum damage assessment: Top is the horizontal distance of the upper Ti layer extending from the intermediate Al layer, and bottom is the horizontal distance of the lower Ti layer extending from the intermediate Al layer: A: Top value less than 300 nm and Bottom value less than 350 nm; B: Top value between 300 nm and 350 nm, or Bottom value between 350 nm and 400 nm; C: Top value greater than 350 nm and Bottom value greater than 400 nm.
[0173] The test results are shown in Table 1.
[0174] Table 1. Performance test results of silver etching solution
[0175] Group Silver residue Aluminum damage level Lifespan / sheet Example 1 none A 850 Example 2 none A 900 Example 3 none A 880 Example 4 none A 890 Example 5 none A 930 Example 6 none A 910 Example 7 none A 860 Example 8 none A 870 Example 9 none A 910 Comparative Example 1 small amount B 600 Comparative Example 2 none C 550 Comparative Example 3 More A 700 Comparative Example 4 small amount B 500
[0176] As can be seen from the test results in Table 1:
[0177] The embodiments of this application (Examples 1-9) all exhibit excellent performance in terms of silver residue control, aluminum damage protection, and service life. Comparative Example 1, lacking a surfactant, showed a small amount of silver residue after testing, resulting in increased aluminum damage (Grade B) and a significantly shortened service life to 600 sheets, demonstrating the crucial role of polyethylene glycol-modified siloxane in improving wettability and reducing aluminum damage. Comparative Example 2, lacking an etching inhibitor, suffered severe aluminum damage (Grade C) and had a service life of only 550 sheets. Comparative Example 3, lacking an etching conditioner, showed significant silver residue, demonstrating the important role of etching conditioners in controlling etching uniformity and preventing silver residue. Comparative Example 4 performed worse than the embodiments of this application in terms of both silver residue and aluminum damage, with a service life of only 500 sheets, significantly lower than the technical solution of this application. In summary, the comparative examples, lacking key components, showed a significant decrease in various performance aspects, fully demonstrating the importance of the synergistic effect between the components in this application in improving the overall performance of the etching solution.
[0178] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A silver etching solution, characterized in that, Calculated by weight percentage, including: The composition includes 50-65% phosphoric acid, 3-12% nitric acid, 8-18% acetic acid, 4-10% organic acid complexing agent, 0.5-2% inorganic salt, 0.05-0.5% surfactant, 0.1-1% corrosion inhibitor, 0.5-3% etching conditioner, and the balance being water; wherein the surfactant is polyethylene glycol modified siloxane.
2. The silver etching solution according to claim 1, characterized in that, The polyethylene glycol-modified siloxane has the following general structural formula: Si(CH3)3-[O-Si(CH3)2]a-[O-Si(CH3)(C2H4O)nH]bO-Si(CH3)3, where a takes values of 5~15, b takes values of 3~8, and n takes values of 10~30.
3. The silver etching solution according to claim 1, characterized in that, The preparation method of the polyethylene glycol modified siloxane is as follows: under nitrogen protection, hydrogen-containing silicone oil, allyl polyethylene glycol and chloroplatinic acid catalyst are added to a reactor, toluene is used as solvent, and the reaction is carried out at 80~110°C for 6~12 hours; after the reaction is completed, the solvent is removed by vacuum distillation to obtain polyethylene glycol modified siloxane. The molar ratio of the hydrogen-containing silicone oil to allyl polyethylene glycol is 1:1.5~2.5; The amount of catalyst used is 50-100 ppm of the total mass of the reactants.
4. The silver etching solution according to claim 1, characterized in that, The corrosion inhibitor is a benzotriazole derivative.
5. The silver etching solution according to claim 4, characterized in that, The corrosion inhibitor is one or more of 5-methylbenzotriazole, 5-carboxybenzotriazole, and 1-hydroxybenzotriazole.
6. The silver etching solution according to claim 1, characterized in that, The etching modifier is one or more of polyacrylamide, polyvinylpyrrolidone, and polyoxyethylene ether.
7. The silver etching solution according to claim 1, characterized in that, The organic acid complexing agent is one or more of citric acid, tartaric acid, oxalic acid, malic acid, and gluconic acid.
8. The silver etching solution according to claim 1, characterized in that, The inorganic salt is one or more of sodium nitrate, potassium nitrate, ammonium nitrate, sodium sulfate, and potassium sulfate.
9. The method for preparing the silver etching solution according to any one of claims 1-8, characterized in that, Includes the following steps: Phosphoric acid, nitric acid, and acetic acid are mixed under cooling conditions to obtain a mixed acid; Organic acid complexing agent, inorganic salt, surfactant, corrosion inhibitor and etching conditioner are dissolved in water in sequence, stirred evenly, and then mixed acid is added. Stirring is continued for 0.5 to 2 hours, and then filtered to obtain silver etching solution.
10. The application of the silver etching solution according to any one of claims 1-8 in a flat panel display OLED.