Post-treatment ion solution for photoresist and method for post-treatment of photoresist

Abstract

The application discloses a post-processing ion solution of photoresist and a photoresist post-processing method. The post-processing ion solution comprises a solvent, active ions and a pH regulating system. The concentration of the active ions in the post-processing ion solution is 0.005 mol / L-0.5 mol / L. The solvent is a mixture of a polar organic solvent and deionized water or water. The active ions can chemically react with active functional groups remaining in the exposed and developed photoresist, so as to realize passivation of the photoresist. The post-processing method comprises the following steps: immersing a photoresist wafer which has been patterned into the post-processing ion solution to perform infiltration treatment, and then performing electroplating. The method can significantly improve the corrosion resistance and structural stability of the photoresist in the electroplating solution through coordination or cross-linking reaction between the active ions and the functional groups of the photoresist, effectively inhibit swelling and permeation plating and the like, and improve forming quality.

Description

Technical Field

[0001] This application belongs to the field of microelectronic processing technology, and specifically relates to a post-processing ionic solution and a photoresist post-processing method for enhancing cross-linking degree. Background Technology

[0002] In processes such as copper filling of through-holes in printed circuit boards (PCBs), bump fabrication, or electroplating of metal structures in micro-electromechanical systems (MEMS), photoresists (such as epoxy resins and acrylates) are commonly used as electroplating masks or molds. The basic process is as follows: photoresist is coated on a substrate, and cross-linking reaction of the colloid in a designated area is achieved through ultraviolet exposure or thermal curing to form a resist layer with a specific pattern structure. Subsequently, electroplating metal deposition is performed in the areas not covered by the colloid.

[0003] However, even after standard UV or thermal curing treatment, existing photoresists may still have microscopic defects or unreacted active sites in their crosslinked network. This structural imperfection leads to challenges for photoresists in actual production environments. The problem is particularly prominent when in prolonged contact with complex electroplating solutions. When in prolonged contact with complex electroplating solutions containing strong acids, strong alkalis, or complexing agents (such as acidic copper sulfate plating solutions or nickel-gold plating solutions), these solutions have strong permeability and chemical corrosiveness. They can easily penetrate and erode the colloid along the microscopic defects inside the photoresist, leading to a series of process problems: (1) pattern swelling, deformation, or even peeling, resulting in distortion of the electroplated pattern and a decrease in precision; (2) contaminants generated by the dissolution of the colloid enter the electrolytic cell, affecting the stability of the plating solution and the purity of the electroplated metal; (3) the interface between the colloid and the substrate is eroded, causing metal creep (seepage plating) phenomenon, which significantly reduces the product yield. Summary of the Invention

[0004] The purpose of this application is to overcome the shortcomings of the prior art and provide a post-processing ionic solution and photoresist post-processing method for enhancing cross-linking degree, so as to improve the corrosion resistance of the colloid to the electroplating solution, thereby ensuring the integrity of the pattern and improving the adhesion and forming quality of the electroplated metal.

[0005] To achieve the above objectives, in a first aspect, this application provides a post-treatment ionic solution comprising a solvent, active ions, and a pH control system; wherein the concentration of the active ions in the post-treatment ionic solution is 0.005 mol / L-0.5 mol / L; the solvent is a mixture of a polar organic solvent and deionized water or water; the active ions are capable of chemically reacting with the active functional groups remaining in the exposed and developed photoresist to passivate the photoresist.

[0006] In one feasible embodiment, the post-treatment ionic solution comprises 0.5%-8% by mass of an effective ionic salt, 30%-70% of a polar organic solvent, 25%-65% of water or deionized water, 0.1%-2% of a pH adjuster, 0-0.1% of a nonionic surfactant, and 0-5% of a penetration enhancer.

[0007] In one feasible embodiment, the volume ratio of the polar organic solvent to deionized water or water in the solvent is 1:1-4; the polar organic solvent is selected from one or both of isopropanol and ethanol.

[0008] In one feasible embodiment, the pH control system includes a pH adjuster and a buffer system; the pH adjuster includes an acidic adjuster and an alkaline adjuster, the acidic adjuster includes at least one of dilute nitric acid or dilute hydrochloric acid; the alkaline adjuster includes at least one of ammonia or organic amine; and the buffer system includes a polyacid salt or a weak acid salt.

[0009] In one feasible embodiment, the chemical reaction between the active ion and the active functional group includes at least one of coordination reaction, complexation reaction, ionic bonding reaction or cross-linking reaction.

[0010] In one feasible embodiment, the active ion is a metal cation, which includes at least one of aluminum ions, zirconium ions, titanium ions, cerium ions, or hafnium ions.

[0011] In one feasible embodiment, the active ion is a metal ion with coordination ability, and the metal ion includes at least one of cerium ion, zinc ion, zirconium ion or tin ion.

[0012] In one feasible embodiment, the active ion is an oxyacid anion or a divalent transition metal ion with coordination ability, wherein the oxyacid anion is selected from at least one of borate ions or molybdate ions; and the divalent transition metal ion with coordination ability includes at least one of chromium ions, zinc ions, copper ions or manganese ions.

[0013] On the other hand, this application provides a post-processing method for photoresist, comprising: before the electroplating process, treating the exposed and developed photoresist with the post-processing ionic solution described in any one of the above-mentioned methods, so that the residual active functional groups in the photoresist react chemically with the active ions to achieve chemical modification and cross-linking enhancement of the photoresist.

[0014] In one feasible embodiment, the photoresist is an epoxy resin-based photoresist, the active functional group is an epoxy group or a hydroxyl group, and the active ion is a metal cation selected from at least one of aluminum ions, zirconium ions, titanium ions, cerium ions, or hafnium ions.

[0015] In one feasible embodiment, the photoresist is an acrylate photoresist, the active functional group is a carboxyl or hydroxyl group, and the active ion is a metal ion with coordination ability, wherein the metal ion is selected from at least one of cerium ions, zinc ions, zirconium ions or tin ions.

[0016] In one feasible embodiment, the photoresist is a phenolic resin-based photoresist, the active functional group is a phenolic hydroxyl group, and the active ion is an oxyacid anion or a divalent transition metal ion with coordination ability. The oxyacid anion is selected from at least one of borate ions or molybdate ions. The divalent transition metal ion with coordination ability includes at least one of chromium ions, zinc ions, copper ions or manganese ions.

[0017] In one feasible embodiment, the following steps are included: Step 1: Expose and develop the substrate coated with photoresist; Step 2: Immerse the patterned photoresist substrate vertically or at an angle into the post-processing ionic solution for wetting. Step 3: Clean and dry the photoresist substrate after impregnation treatment; Step 4: Immerse the photoresist substrate in an organic solvent to remove moisture from the colloidal micropores of the photoresist, and then dry the substrate. Step 5: Immerse the substrate in the electroplating solution for electroplating.

[0018] In one feasible embodiment, the electroplating process includes via filling of printed circuit boards, bump fabrication, or electroplating of metal structures in microelectromechanical systems.

[0019] This application has the following advantages compared with the prior art: By employing ion solution post-treatment, specific ions in the solution can penetrate into the colloidal interior of the photoresist, undergoing coordination, complexation, or ionic bonding reactions with residual active functional groups (such as epoxy, carboxyl, and hydroxyl groups) in the polymer network. This creates additional physicochemical cross-linking points on top of the existing cross-linked network, resulting in a denser cross-linked structure on the surface and within the cured photoresist, fundamentally improving its resistance to electroplating solutions. This process is mild and does not cause macroscopic changes in pattern dimensions, effectively ensuring pattern integrity and electroplating quality. Simultaneously, the colloidal stability is significantly improved, completely eliminating plating bleeding and resulting in clearer edges and stronger adhesion of electroplated metal lines. Furthermore, this method exhibits good compatibility with existing standard photolithography electroplating processes. Specific Implementation

[0020] To illustrate the technical content, structural features, achieved objectives, and effects of the invention in detail, the technical solutions in the embodiments of this application are described. Obviously, the described embodiments are merely a part of the embodiments of this application, and not all of them. In the following description, for illustrative purposes, numerous specific details are set forth to provide a detailed description of various exemplary embodiments or implementations of the invention.

[0021] The photoresist post-processing method provided in this application is based on the fact that, before electroplating, a specific ionic solution is used to post-process the patterned and initially cured photoresist to improve its density and chemical stability, thereby enhancing its tolerance in the electroplating process.

[0022] Specifically, after the photoresist has been patterned and initially cured, it is immersed in the post-processing ionic solution disclosed in this application. This allows the active ions in the solution to effectively penetrate into the photoresist matrix and react with the residual active functional groups in the polymer network. Examples of active functional groups include epoxy and hydroxyl groups in epoxy resin photoresists, carboxyl and hydroxyl groups in acrylate photoresists, and phenolic hydroxyl groups in phenolic resin photoresists. Through coordination, complexation, or ionic bonding reactions, the active ions and the aforementioned functional groups construct additional physicochemical crosslinking points on top of the original crosslinked network of the photoresist. The mechanism of action is mainly reflected in the following three aspects: (1) The introduced ionic bonds or coordination structures with large volume can effectively fill the free volume between polymer molecular chains. This filling effect makes the cross-linked network of photoresist more compact, thereby forming a barrier layer in physical space, which significantly hinders the penetration and diffusion of electroplating solution molecules into the colloid body, thus preventing the photoresist pattern from swelling, deforming, or even peeling off from the substrate, thereby causing the metal pattern obtained by electroplating to be distorted.

[0023] (2) Through ionic reactions, the terminal active groups in the photoresist that are sensitive to the electroplating solution are effectively consumed, thereby reducing the chemical activity of the colloid surface. On the one hand, this reduces the probability of chemical reactions between the photoresist and corrosive components (such as acids, complexing agents, etc.) in the electroplating solution, thus improving its chemical stability; on the other hand, it prevents dissolved contaminants from entering the electroplating solution, reducing the purity of the electroplated metal and affecting the long-term stability of the electroplating solution.

[0024] (3) The interface between the colloid and the substrate is a weak point in terms of corrosion resistance. Once the interface is eroded by the plating solution, the electroplated metal will grow under the colloid, forming the so-called "climbing" or "penetration" phenomenon. This will directly lead to short circuits or abnormal morphology, which is one of the key factors affecting product yield. The post-processing process of this application forms an extremely thin ion-polymer composite layer in situ on the surface of the photoresist. This composite layer can effectively seal the inherent micropores and micro-defects on the surface of the colloid, significantly improve the barrier ability of the photoresist-substrate interface, and fundamentally eliminate the occurrence of penetration.

[0025] Through the combined effect of the above mechanisms, this application provides a post-processing ionic solution and photoresist post-processing method for enhancing cross-linking degree. While maintaining the dimensional accuracy of the photoresist pattern, it significantly improves its resistance to electroplating solution corrosion, ensuring the integrity and yield of the electroplated pattern.

[0026] Specifically, a photoresist post-processing method includes: S1: Expose, develop, and dry the substrate coated with photoresist; S2: Immerse the obtained patterned photoresist substrate vertically or at an angle into the corresponding post-processing ionic solution for wetting treatment; S3: Immerse the photoresist substrate after wetting treatment into deionized water for 10-30 seconds to remove most of the residual ionic solution on the surface. S4: Immerse the photoresist substrate in an organic solvent (such as isopropanol) for 10-20 seconds to remove moisture from the colloidal micropores of the photoresist. Blow the substrate dry with a nitrogen gun and place it on a hot plate to dry for 1-2 minutes to remove residual moisture. S5: Immerse the substrate in the electroplating solution for electroplating.

[0027] Photoresist undergoes exposure, development, and drying to obtain a patterned substrate; however, some residual active functional groups remain on its surface or inside. For epoxy resin photoresists, the active functional groups are epoxy and hydroxyl groups; for acrylate photoresists, the active functional groups are carboxyl and hydroxyl groups; and for phenolic resin photoresists, the active functional group is phenolic hydroxyl groups.

[0028] In this embodiment, the post-processing ionic solution mainly comprises a solvent, active ions, and a pH control system. The solvent is either a polar organic solvent and deionized water, or a mixture of a polar organic solvent and water, to ensure that the swelling capacity of the photoresist is retained without damaging the colloid.

[0029] Specifically, the post-treatment ionic solution includes 0.5%-8% effective ionic salt, 30%-70% polar organic solvent, 25%-65% water or deionized water, 0.1%-2% pH adjuster, 0-0.1% nonionic surfactant, and 0-5% penetration enhancer.

[0030] Preferably, the volume ratio of the polar organic solvent to water or deionized water is 1:1-4. The polar organic solvent is selected from one or a mixture of two pure solvents, such as isopropanol or ethanol.

[0031] Nonionic surfactants and penetration enhancers can be added or not.

[0032] Furthermore, the concentration of active ions in the post-treatment ionic solution is 0.005 mol / L-0.5 mol / L, obtained by compounding ionic salts with solvents. The active ions are selected according to the type of photoresist using the method described below, while the effective ionic salt is selected to be consistent with the anions in the subsequent electroplating solution system to avoid introducing other anions.

[0033] Furthermore, to accommodate different types of photoresists, the active ions in the post-treatment ion solution are selected based on the type of functional groups contained in the patterned photoresist substrate, and are capable of chemically reacting with these active functional groups. The correspondence between active ions and photoresist functional groups and their mechanism of action are as follows: When the photoresist is an epoxy resin, its active functional groups include epoxy groups and / or hydroxyl groups, and the active ions are metal cations, such as aluminum ions, zirconium ions, titanium ions, cerium ions, or hafnium ions, etc., which are high-valence metal ions. The mechanism of action lies in the fact that high-valence metal cations have strong coordination ability, which can form stable coordination cross-linking structures with oxygen atoms in the photoresist, thereby significantly improving the resistance and structural stability of the colloid in acidic plating solutions. In the post-treatment process, the pH of the post-treatment ionic solution is 3.5-4.5, the reaction temperature is 30-60℃, and the treatment time is 10-30 min.

[0034] When the photoresist is an acrylate-based material, its active functional groups include carboxyl and / or hydroxyl groups, and the active ions are metal ions with strong coordination ability, such as at least one of cerium, zinc, zirconium, or tin ions. The mechanism of action lies in the fact that these active ions have good coordination affinity with functional groups such as carboxyl and hydroxyl groups, which can effectively enhance the photoresist's corrosion resistance and interfacial bonding strength in alkaline plating solutions. In the post-treatment process, the pH of the post-treatment ionic solution is 3.5-4.5, the reaction temperature is room temperature-35℃, and the treatment time is 5-15 minutes.

[0035] When the photoresist is a phenolic resin, its functional group includes phenolic hydroxyl groups, and the active ions are oxyacid anions or other divalent transition metal ions with coordination ability. Oxyacid anions include borate or molybdate ions; divalent transition metal ions with coordination ability include at least one of chromium, zinc, copper, and manganese ions. The mechanism of action is that borate or molybdate ions can react with the phenolic hydroxyl groups to form stable borate esters or coordination compounds, thereby improving the chemical stability of the photoresist in various plating bath environments. This makes it suitable for electroplating systems with complex structures and high process requirements. In the post-treatment process, the pH of the post-treatment ionic solution is 8.5-9.5, the reaction temperature is 50-60℃, and the treatment time is 15-25 min.

[0036] The aforementioned pH control system includes a pH adjuster and a buffer system. The pH adjuster includes acidic and basic adjusters, used to adjust the pH of the solution to a target range. The acidic adjuster includes at least one of dilute nitric acid and dilute hydrochloric acid; the basic adjuster includes at least one of ammonia and organic amines. The buffer system acts as a buffer in the solution to maintain pH balance during the reaction. The buffer system includes polybasic acid salts or weak acid salts, and some of the aforementioned effective ionic salts can also be used as buffer systems. In some embodiments, the buffer system may also be potassium dihydrogen phosphate-dipoxatium hydrogen phosphate.

[0037] In this embodiment, to improve the wettability of the solution, 0.01-0.1% of a nonionic surfactant can be added to the solution. To promote the diffusion of ions inside the photoresist, 1-5% of a penetration enhancer, such as dimethyl sulfoxide, can be added to the solution.

[0038] In this embodiment, a photoresist substrate with the target pattern is obtained using a conventional photolithography process, and this substrate is used as the processing object. The photoresist post-processing method of this application can also be used as a pre-processing method for electroplating.

[0039] In this embodiment, step S2 is performed in a constant temperature water bath shaker, immersing the substrate in the post-treatment ionic solution step to ensure uniformity and repeatability. After the treatment is completed, the substrate is removed with tweezers.

[0040] Considering that different types of photoresists have different types of active ions and processing conditions, there are also differences.

[0041] Example 1: Post-processing of epoxy resin photoresist.

[0042] The active functional groups of the photoresist include epoxy groups and / or hydroxyl groups. Aluminum nitrate is selected as the active ion source, and a post-treatment ion solution with an ion concentration of 0.05 mol / L to 0.2 mol / L is prepared. The pH of the solution is maintained in a weakly acidic range of 3.5 to 4.5 by a pH control system to prevent the hydrolysis of aluminum ions and maintain their reactivity. Then, the patterned photoresist substrate is immersed in the post-treatment solution and reacted at a temperature of 40 to 50°C for 10 to 30 minutes to allow aluminum ions to fully coordinate with the functional groups of the photoresist, thereby improving the tolerance to acidic plating solutions.

[0043] Example 2: Post-processing of acrylate photoresist.

[0044] The active functional groups of the photoresist include carboxyl and / or hydroxyl groups. Zinc acetate is selected as the active ion source, and a post-treatment ion solution with an ion concentration of 0.1 mol / L to 0.3 mol / L is prepared. The pH of the solution is maintained in a weakly acidic range of 3.5 to 4.5 by a pH control system to ensure that zinc ions exist stably in a free state and have good coordination activity. Then, the patterned photoresist substrate is immersed in the solution and reacted at a temperature of room temperature to 35°C for 5 to 15 minutes to allow zinc ions to fully coordinate with the carboxyl or hydroxyl groups in the photoresist, thereby enhancing the colloid's corrosion resistance in alkaline plating solutions.

[0045] Example 3: Post-treatment of phenolic resin photoresist.

[0046] The active functional groups of the photoresist include phenolic hydroxyl groups. A post-treatment ion solution with a borate ion concentration of 0.2 mol / L to 0.5 mol / L is prepared using a borate-borax buffer solution. The pH of the solution is maintained in a weakly alkaline range of 8.5 to 9.5 by a pH control system to promote the formation of stable borate ester bonds between borate ions and phenolic hydroxyl groups. Then, the patterned photoresist substrate is immersed in this solution and reacted at a temperature of 50 to 60°C for 15 to 25 minutes to ensure that the crosslinking reaction is fully carried out, thereby significantly improving the chemical stability of the photoresist in complex plating bath environments.

[0047] The following examples and comparative examples will be used to verify the corrosion resistance of the post-processed photoresist substrate to electroplating solution and the forming quality. Example

[0048] SU-8 2150 photoresist was spin-coated onto a silicon wafer, and a columnar mold with an aspect ratio of 5:1 was fabricated using standard processes (coating, photolithography, development, and hardening). The post-treatment ionic solution was a 0.1 mol / L aluminum nitrate solution, with the pH maintained at 4.0 using a pH control system. The mold was immersed in the post-treatment ionic solution and soaked at a constant temperature of 45°C for 20 minutes. After treatment, the mold was removed with tweezers and then sequentially rinsed in deionized water for 20-30 seconds, followed by rinsing in isopropanol for 20-40 seconds. The mold was then dried with a nitrogen gun and placed on a hot plate to dry for 2-5 minutes.

[0049] The columnar mold, after being treated with post-treatment ionic solution, was immersed in an acidic copper sulfate plating solution and electroplated at a current density of 2 ASD.

[0050] Comparative example: SU-8 2150 photoresist was spin-coated onto a silicon wafer, and a columnar mold with an aspect ratio of 5:1 was fabricated using standard processes. Without post-treatment ion exchange solution immersion, the columnar mold was directly immersed in an acidic copper sulfate plating solution and electroplated at a current density of 2 ASD.

[0051] Comparison of experimental results after 30 minutes of electroplating: In Example 4, the top edge of the mold remains clear, the resulting copper layer is bright, and the bottom is smooth when the adhesive is removed.

[0052] In the comparative example, the top of the mold showed obvious swelling, some of the bottom showed plating seepage, and some of the copper layer surfaces showed nodules or roughness.

[0053] The results show that, under the same electroplating conditions, the swelling ratio of the colloidal material treated with the post-treatment ionic solution can be reduced by more than 70%, the erosion resistance time is significantly extended, and the chemical resistance of the photoresist is significantly improved.

[0054] The photoresist substrate coated with the post-treatment ion solution has high pattern fidelity, the treatment process is gentle, the edges of the electroplated metal lines are clearer, the adhesion is stronger, and the electroplating quality is higher.

[0055] The post-processing method of this application has strong process compatibility and good compatibility with existing standard photolithography and electroplating processes. It does not require modification of the preceding and following processes and can be used for pre-processing of electroplating processes such as through-hole filling, bump fabrication, or electroplating of metal structures in microelectromechanical systems on printed circuit boards, thus having high versatility.

[0056] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope. The scope of protection of the present invention is defined by the appended claims, specification, and their equivalents.

Claims

1. A post-treatment ionic solution for photoresist, characterized in that, The post-treatment ionic solution comprises a solvent, active ions, and a pH control system, wherein the concentration of the active ions in the post-treatment ionic solution is 0.005 mol / L-0.5 mol / L; the solvent is a mixture of a polar organic solvent and deionized water or water; the active ions can chemically react with the active functional groups remaining in the exposed and developed photoresist to achieve passivation of the photoresist.

2. The post-treatment ionic solution according to claim 1, characterized in that, The post-treatment ionic solution comprises 0.5%-8% effective ionic salt, 30%-70% polar organic solvent, 25%-65% water or deionized water, 0.1%-2% pH adjuster, 0-0.1% nonionic surfactant, and 0-5% penetration enhancer.

3. The post-treatment ionic solution according to claim 2, characterized in that, The volume ratio of the polar organic solvent to deionized water or water in the solvent is 1:1-4; the polar organic solvent is selected from one or both of isopropanol and ethanol.

4. The post-treatment ionic solution according to claim 1, characterized in that, The pH control system includes a pH adjuster and a buffer system; the pH adjuster includes an acidic adjuster and an alkaline adjuster, the acidic adjuster includes at least one of dilute nitric acid or dilute hydrochloric acid; the alkaline adjuster includes at least one of ammonia or organic amine; the buffer system includes polyacid salts or weak acid salts.

5. The post-treatment ionic solution according to claim 1, characterized in that, The chemical reaction between the active ions and the active functional groups includes at least one of coordination reaction, complexation reaction, ionic bonding reaction or cross-linking reaction.

6. The post-treatment ionic solution according to claim 5, characterized in that, The active ion is a metal cation, which includes at least one of aluminum ion, zirconium ion, titanium ion, cerium ion or hafnium ion.

7. The post-treatment ionic solution according to claim 5, characterized in that, The active ion is a metal ion with coordination ability, and the metal ion includes at least one of cerium ion, zinc ion, zirconium ion or tin ion.

8. The post-treatment ionic solution according to claim 5, characterized in that, The active ion is an oxyacid anion or a divalent transition metal ion with coordination ability. The oxyacid anion is selected from at least one of borate ion or molybdate ion. The divalent transition metal ion with coordination ability includes at least one of chromium ion, zinc ion, copper ion or manganese ion.

9. A post-processing method for photoresist, characterized in that: Before the electroplating process, the photoresist that has been exposed and developed is treated with the post-treatment ionic solution as described in any one of claims 1-5, so that the residual active functional groups in the photoresist react with the active ions to achieve chemical modification and cross-linking enhancement of the photoresist.

10. The method according to claim 9, characterized in that, The photoresist is an epoxy resin-based photoresist, the active functional group is an epoxy group or a hydroxyl group, and the active ion is a metal cation, which is selected from at least one of aluminum ions, zirconium ions, titanium ions, cerium ions or hafnium ions.

11. The method according to claim 9, characterized in that, The photoresist is an acrylate photoresist, the active functional group is a carboxyl or hydroxyl group, and the active ion is a metal ion with coordination ability, wherein the metal ion is selected from at least one of cerium ions, zinc ions, zirconium ions or tin ions.

12. The method according to claim 9, characterized in that, The photoresist is a phenolic resin-based photoresist, the active functional group is a phenolic hydroxyl group, and the active ion is an oxyacid anion or a divalent transition metal ion with coordination ability. The oxyacid anion is selected from at least one of borate ions or molybdate ions. The divalent transition metal ions with coordination ability include at least one of chromium ions, zinc ions, copper ions or manganese ions.

13. The method according to claim 9, characterized in that, Includes the following steps: Step 1: Expose and develop the substrate coated with photoresist; Step 2: Immerse the patterned photoresist substrate vertically or at an angle into the post-processing ionic solution for wetting. Step 3: Clean and dry the photoresist substrate after impregnation treatment; Step 4: Immerse the photoresist substrate in an organic solvent to remove moisture from the colloidal micropores of the photoresist, and then dry the substrate. Step 5: Immerse the substrate in the electroplating solution for electroplating.

14. The method according to claim 9, characterized in that: The electroplating process includes through-hole filling of printed circuit boards, bump fabrication, or electroplating of metal structures in microelectromechanical systems.