Blind hole over-speed electroplating leveling agent, electroplating liquid and application of blind hole over-speed electroplating leveling agent

Abstract

The invention discloses a blind hole overspeed electroplating leveling agent, which is prepared from the following raw materials: tertiary amine, glycidyl ether, a quaternization reagent and water, and the molar ratio of the tertiary amine to the glycidyl ether to the quaternization reagent is 1: (0.1-10): (0.1-10). The leveling agent disclosed by the invention is applied to high-current copper plating, and has excellent hole filling capability and excellent surface copper control capability. And under the combined action of the copper ions, sodium 3, 3 '-dithiodipropane sulfonate and PEG8000, deposition of the copper ions at the low potential position is accelerated, copper grains are finer, and therefore the copper plating rate is increased, and meanwhile a copper layer is not coarsened. The electroplating solution has good hole filling capacity for blind hole filling of various sizes, the electroplating solution is stable in performance, a plating layer is bright, crystals are fine, ductility is good, electroplating copper thickness distribution is uniform, electroplating under the large current density can be achieved, and the electroplating efficiency is greatly improved.

Description

Technical Field

[0001] The invention relates to a blind hole ultra-speed electroplating leveler, an electroplating solution and application thereof, and relates to C25D, in particular to the field of chemistry or physical metallurgy. Background Art

[0002] With the advancement of science and technology, the demand for integrated circuits and printed circuit boards in electronic information products is increasing, and the technical requirements for printed circuit boards PCB are getting higher and higher. Metal copper has the advantages of being cheap, low toxicity, and good conductivity, so it is widely used in PCB boards. The traditional copper plating method has great harm to the environment and has been gradually eliminated. Copper plating is now mainly carried out through the sulfate copper plating system, but the traditional leveling agent has low plating efficiency when working in the electroplating copper solution, which affects the production efficiency. In order to improve the electroplating efficiency, the copper plating current density will be increased, but the higher current density will lead to a decrease in the plating ability of the blind hole, the coating will be rough and easy to produce core, resulting in signal loss during high-frequency signal transmission of the PCB board, which cannot meet the use requirements of the PCB board.

[0003] Chinese invention patent CN201910458563.8 discloses a copper electroplating hole filling leveler and its preparation method and application. Block polymers and quaternized block polymers are used as copper electroplating hole filling levelers, combined with wetting agents and accelerators to form acid copper-type electroplating hole filling additives, which are applied to through holes or blind holes on semiconductor substrates or printed circuit boards to achieve full copper filling. However, the current density during copper electroplating is 2.0A, and the electroplating rate is slow. Chinese invention patent CN202111432088.0 discloses a quaternary ammonium salt leveler and its preparation method, an electroplating solution containing it, and an electroplating method. A nitrogen-containing heterocyclic compound and an epoxy compound are polymerized to first obtain a tertiary amine compound, and then a quaternization reaction is completed with a halide. The obtained leveler has a stronger leveling ability, can obtain a thinner electroplating thickness, and is more conducive to the production of fine circuits, but the electroplating efficiency is not high. Summary of the invention

[0004] In order to develop a leveler that can be used in a plating solution under high current density electroplating, the first aspect of the present invention provides a blind hole ultra-speed electroplating leveler, the preparation raw materials include tertiary amine, glycidyl ether, quaternary ammonium agent and water, and the molar ratio of the tertiary amine, glycidyl ether and quaternary ammonium agent is 1: (0.1-10): (0.1-10).

[0005] As a preferred embodiment, the molar ratio of the tertiary amine, the glycidyl ether, and the quaternizing agent is 1:(1-10):(1-10).

[0006] The molar ratio of the tertiary amine, the glycidyl ether and the quaternary ammonium agent is 1:(0.1-10):(0.1-10).

[0007] As a preferred embodiment, the tertiary amine has a structure of Formula I: Wherein X, Y, and Z are selected from C1-C 10 Straight chain alkyl, C1-C 10 One of branched alkyl, aromatic, heteroaromatic, carboxyl, sulfonic acid, and heteroatom groups containing N, O, and S; wherein n is selected from one of 1, 2, and 3.

[0008] As a preferred embodiment, the tertiary amine is selected from one or a combination of aminosulfonic acid, amino acid, diamine, amino ether, and amino thioether compounds; the tertiary amine is selected from one of monosubstituted organic amines, disubstituted organic amines, and trisubstituted organic amines.

[0009] As a preferred embodiment, the glycidyl ether is selected from one or a combination of monofunctional glycidyl ether, difunctional glycidyl ether, and polyfunctional glycidyl ether; the monofunctional glycidyl ether comprises formula II: The structure of the difunctional glycidyl ether comprises formula III: Formula IV: Formula V: Formula VI: structure.

[0010] As a preferred embodiment, the monofunctional glycidyl ether is selected from one or a combination of benzyl glycidyl ether, phenyl glycidyl ether, butyl glycidyl ether, octyl glycidyl ether, carbon dodecyl glycidyl ether, and allyl glycidyl ether; the difunctional glycidyl ether is selected from one or a combination of ethylene glycol glycidyl ether, polyethylene glycol glycidyl ether, polypropylene glycol glycidyl ether, 1,4-butanediol glycidyl ether, 1,6-hexanediol diglycidyl ether, diethylene glycol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, and neopentyl glycol diglycidyl ether; the multifunctional glycidyl ether is selected from one or a combination of glycerol triglycidyl ether, glycerol propoxy triglycidyl ether, and trimethylolpropane triglycidyl ether.

[0011] As a preferred embodiment, the quaternizing agent is a halogenated hydrocarbon, and the halogenated hydrocarbon is selected from one or a combination of alkyl halogenated hydrocarbons, benzyl halogenated hydrocarbons, allyl halogenated hydrocarbons, and propargyl halogenated hydrocarbons.

[0012] As a preferred embodiment, the preparation method of the leveling agent comprises the following steps: mixing tertiary amine, glycidyl ether, quaternary ammonium agent and water, reacting at a temperature of 70-90° C. for a reaction time of 12-24 h, and obtaining the leveling agent after the reaction.

[0013] As a preferred embodiment, the preparation method of the leveling agent comprises the following steps: adding tertiary amine and deionized water into a reactor, stirring, controlling the reaction temperature to 55-65°C, adding glycidyl ether by injection pump, dropping for 8-12 minutes, reacting exothermically, and controlling the feeding rate to keep the temperature below 65°C; then heating to 65-75°C for reaction for 5-7h, adding a quaternary ammonium agent, continuing the reaction for 5-7h, then cooling to room temperature, and adjusting the pH to 1-3 to obtain the product.

[0014] As a preferred embodiment, the reagent used to adjust the pH is a 50 wt % sulfuric acid aqueous solution.

[0015] As a preferred embodiment, the molecular weight of the leveling component in the leveling agent after the reaction is 500-20000 Da, and the pH of the leveling agent is 1.0-3.0.

[0016] As a preferred embodiment, the molecular weight of the leveling component in the leveling agent after the reaction is 500-5000Da.

[0017] The applicant found in the experiment that the current of copper plating is small and the efficiency is low when the traditional leveling liquid is used for copper electroplating, which affects the production capacity. After the traditional leveling agent increases the plating current, the all-plating ability will decrease, the coating will be rough and it is very easy to produce core wrapping, resulting in signal loss during high-frequency signal transmission, which cannot meet the use requirements of PCB boards. In this application, by introducing tertiary amine, it is applied to copper plating with high current, and has excellent hole filling ability and excellent surface copper control ability. The possible reason is guessed that the steric hindrance of the tertiary amine is large, and it has a strong positive charge like copper ions in the leveling agent, which is easy to adsorb at the high current density of the device surface, and has a strong electronegativity. The leveling agent competes with copper ions, making it difficult for copper ions to settle at high current, but it will not affect the copper plating in the low current area, making the copper plating surface flat, and at the same time, due to the small impact on the low current density area, the hole phenomenon caused by premature sealing during the hole filling process can be avoided, and the formed copper crystals are more delicate, and it also has a good copper electroplating effect at high current density.

[0018] A second aspect of the present invention provides an electroplating solution comprising the blind hole ultra-speed electroplating leveler according to any one of claims 1 to 8, wherein the mass concentration of the leveler in the electroplating solution is 10-100 ppm.

[0019] As a preferred embodiment, the raw materials for preparing the electroplating solution include 40-120 g / L sulfuric acid, 120-240 g / L copper sulfate pentahydrate, 40-80 ppm chloride ions, 1-10 ppm accelerator, 60-6000 ppm inhibitor, and 10-100 ppm leveler.

[0020] As a preferred embodiment, the accelerator is sodium poly(disulfide propane sulfonate) (SPS) and the inhibitor is PEG8000.

[0021] In this application, sodium polydisulfide dipropane sulfonate is used as an accelerator. The system produces a depolarization effect in the presence of chloride ions, accelerates the deposition of copper ions at low potentials, and enters the copper plating layer to affect the crystal structure of the plating layer, making the copper grains more refined, thereby increasing the copper plating rate while not coarsening the copper layer. The inhibitor used is PEG8000, which works synergistically with the leveling agent to inhibit the copper ions from being deposited at low potentials under the action of chloride ions. 2+ During high potential deposition, the accelerator is carried to the cathode depression, thereby promoting the deposition of the accelerator in the pores. 2+ The electron transfer that forms a stable conversion between the double electrical layers of metallic copper acts as a carrier medium for the copper plating additive to a certain extent, promoting the full performance of the copper plating additive.

[0022] The third aspect of the present invention provides an application of an electroplating solution for use in circuit board electroplating and / or integrated circuit electroplating, wherein the current density during electroplating is 3.0-5.0 A / dm 2 .

[0023] As a preferred embodiment, the temperature during electroplating is 30-50° C., and the electroplating time is 20-40 min.

[0024] As a preferred embodiment, the size of the electroplated blind hole is 2-6 mil in diameter and 2-5 mil in depth.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The blind hole ultra-speed electroplating leveler of the present invention, by introducing tertiary amine, is applied to high current copper plating and has excellent hole filling ability and excellent surface copper control ability.

[0027] (2) The blind hole ultra-fast electroplating leveler of the present invention is applied to the electroplating solution and acts together with sodium polydisulfide dipropane sulfonate and PEG8000 to accelerate the deposition of copper ions at low potentials and refine the copper grains, thereby increasing the copper plating rate without coarsening the copper layer.

[0028] (3) The blind hole ultra-speed electroplating leveler of the present invention is applied to the electroplating solution. When electroplating the blind hole, it is suitable for the insoluble anode and has good filling ability for blind holes of various sizes. The plating solution is stable, the coating is bright, the crystals are fine, the ductility is good, and the thickness of the electroplated copper is uniformly distributed. Electroplating under high current density can be achieved, and the electroplating efficiency is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a diagram showing the effect of filling a blind hole after the leveling agent prepared in Example 1 is applied to the electroplating solution;

[0030] Figure 2 This is a diagram showing the effect of filling a blind hole after the leveling agent prepared in Example 2 is applied to the electroplating solution;

[0031] Figure 3 This is a diagram showing the filling effect of the leveling agent prepared in Example 3 after being applied to electroplating blind holes in the electroplating solution. DETAILED DESCRIPTION

[0032] Example 1

[0033] A blind hole ultra-speed electroplating leveler, the preparation raw materials include tertiary amine, glycidyl ether, quaternary ammonium agent and water, the molar concentrations of the tertiary amine, glycidyl ether and quaternary ammonium agent are 0.03mmol, 0.02mmol and 0.01mmol respectively. The volume of deionized water is 25mL.

[0034] The tertiary amine is aminosulfonic acid, the glycidyl ether is ethylene glycol glycidyl ether, and the quaternizing agent is benzyl chloride.

[0035] The preparation method of the leveling agent comprises the following steps: adding tertiary amine and deionized water into a reactor, stirring, controlling the reaction temperature to 60°C, adding glycidyl ether by an injection pump, dripping for 10 minutes, reacting exothermically, and controlling the feeding speed to keep the temperature below 55°C; then heating to 70°C for reaction for 6 hours, adding a quaternary ammonium agent, continuing the reaction for 6 hours, then cooling to room temperature, and adjusting the pH to 3 to obtain the leveling agent.

[0036] The reagent used for adjusting pH is a 50wt% sulfuric acid aqueous solution.

[0037] Example 2

[0038] A blind hole ultra-speed electroplating leveler, the preparation raw materials include tertiary amine, glycidyl ether, quaternary ammonium agent and water, the molar concentrations of the tertiary amine, glycidyl ether and quaternary ammonium agent are 0.03mmol, 0.02mmol and 0.01mmol respectively. The volume of deionized water is 25mL.

[0039] The tertiary amine is D(-)-isovaline, the glycidyl ether is ethylene glycol glycidyl ether, and the quaternizing agent is benzyl chloride.

[0040] The preparation method of the leveling agent comprises the following steps: adding tertiary amine and deionized water into a reactor, stirring, controlling the reaction temperature to 60°C, adding glycidyl ether by an injection pump, dripping for 10 minutes, reacting exothermically, and controlling the feeding speed to keep the temperature below 65°C; then heating to 70°C for reaction for 6 hours, adding a quaternary ammonium agent, continuing the reaction for 6 hours, then cooling to room temperature, and adjusting the pH to 3 to obtain the leveling agent.

[0041] The reagent used for adjusting pH is a 50wt% sulfuric acid aqueous solution.

[0042] Example 3

[0043] A blind hole ultra-speed electroplating leveler, the preparation raw materials include tertiary amine, glycidyl ether, quaternary ammonium agent and water, the molar concentrations of the tertiary amine, glycidyl ether and quaternary ammonium agent are 0.03mmol, 0.02mmol and 0.01mmol respectively. The volume of deionized water is 25mL.

[0044] The tertiary amine is a diamine, the glycidyl ether is ethylene glycol glycidyl ether, and the quaternizing agent is benzyl chloride.

[0045] The preparation method of the leveling agent comprises the following steps: adding tertiary amine and deionized water into a reactor, stirring, controlling the reaction temperature to 60°C, adding glycidyl ether by an injection pump, dripping for 10 minutes, reacting exothermically, and controlling the feeding speed to keep the temperature below 65°C; then heating to 70°C for reaction for 6 hours, adding a quaternary ammonium agent, continuing the reaction for 6 hours, then cooling to room temperature, and adjusting the pH to 3 to obtain the leveling agent.

[0046] The reagent used for adjusting pH is a 50wt% sulfuric acid aqueous solution.

[0047] Example 4

[0048] A blind hole ultra-fast electroplating leveler, the specific implementation method is the same as that of Example 1, except that the dripping time of glycidyl ether is 3 minutes. The formed leveler gelled and the preparation failed. (The reason is that the reaction temperature rises quickly, and the heat is difficult to transfer out in the system in time, resulting in side reactions and even gelation)

[0049] Performance Testing

[0050] Prepare 1.5 L of plating solution according to Table 1 below.

[0051] Table 1

[0052] Components concentration Copper sulfate pentahydrate 240g / L sulfuric acid 40g / L Chloride ion: hydrochloric acid 90ppm Accelerator: Sodium polydisulfide dipropane sulfonate 2ppm Inhibitor: PEG8000 400ppm Leveling agent 50ppm

[0053] The sodium poly(dipropane disulfide sulfonate) was purchased from Shanghai Bid Pharmaceutical Technology Co., Ltd.

[0054] The prepared raw materials are mixed in a Haring tank, and stirred evenly to obtain an electroplating solution.

[0055] After the electroplating sheet is pre-treated by pickling for 2 minutes, degreasing for 2 minutes, and micro-etching for 2 minutes, it enters the electroplating process.

[0056] Electroplating method: Place the pre-treated HDI double-sided four-layer blind hole board with the following specifications: board thickness 1mm, blind hole diameter 120μm×85μm in a 1.5L Haring tank with air stirring device and insoluble anode filled with copper plating solution. Electroplating is carried out for 25 minutes with DC 4ASD and the electroplating temperature is 30℃.

[0057] Use a microscope to measure the copper thickness of the plated board, the Dimple value of the filled hole, and the voids in the filled hole. See the photo of the filled hole for details. Figure 1-3 The measurement results are shown in Table 2.

[0058] Table 2

[0059] Dimple value of hole filling / μm Copper thickness of plated surface Example 1 4.87μm 19.16μm Example 2 5.00μm 18.36μm Example 3 3.69μm 20.25μm

[0060] As can be seen from Table 2, the leveling agent synthesized by the present invention has strong burst capacity. It is suitable for high current short-time electroplating, and can complete hole filling in 25 minutes, which significantly improves production efficiency. Using this additive formula, a depression within 5μm can be obtained. The hole filling performance is excellent, and there is no poor quality such as plating voids and cracks in the filled blind hole.

Claims

1. A blind hole ultra-fast electroplating leveling agent, characterized in that: The preparation raw materials include tertiary amine, glycidyl ether, quaternary ammonium agent and water, and the molar ratio of the tertiary amine, glycidyl ether and quaternary ammonium agent is 1:(0.1-10):(0.1-10).

2. The blind hole ultra-fast electroplating leveling agent according to claim 1, characterized in that: The tertiary amine has a structure of Formula I: Wherein X, Y, and Z are selected from C1-C 10 Straight chain alkyl, C1-C 10 One of branched alkyl, aromatic, heteroaromatic, carboxyl, sulfonic acid, and heteroatom groups containing N, O, and S; wherein n is selected from one of 1, 2, and 3.

3. The blind hole ultra-fast electroplating leveling agent according to claim 1, characterized in that: The tertiary amine is selected from one or a combination of aminosulfonic acid, amino acid, diamine, amino ether, and amino thioether compounds; the tertiary amine is selected from one of monosubstituted organic amines, disubstituted organic amines, and trisubstituted organic amines.

4. The blind hole ultra-fast electroplating leveling agent according to claim 1, characterized in that: The glycidyl ether is selected from one or a combination of monofunctional glycidyl ether, difunctional glycidyl ether, and polyfunctional glycidyl ether; the monofunctional glycidyl ether comprises formula II: The structure of the difunctional glycidyl ether comprises formula III: Formula IV: Formula V: Formula VI: One of the structures.

5. The blind hole ultra-fast electroplating leveling agent according to claim 4, characterized in that: The monofunctional glycidyl ether is selected from one or a combination of benzyl glycidyl ether, phenyl glycidyl ether, butyl glycidyl ether, octyl glycidyl ether, carbon dodecyl glycidyl ether, and allyl glycidyl ether; the difunctional glycidyl ether is selected from one or a combination of ethylene glycol glycidyl ether, polyethylene glycol glycidyl ether, polypropylene glycol glycidyl ether, 1,4-butanediol glycidyl ether, 1,6-hexanediol diglycidyl ether, diethylene glycol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, and neopentyl glycol diglycidyl ether; the multifunctional glycidyl ether is selected from one or a combination of glycerol triglycidyl ether, glycerol propoxy triglycidyl ether, and trimethylolpropane triglycidyl ether.

6. The blind hole ultra-fast electroplating leveling agent according to claim 1, characterized in that: The quaternizing agent is a halogenated hydrocarbon, and the halogenated hydrocarbon is selected from one or a combination of alkyl halogenated hydrocarbons, benzyl halogenated hydrocarbons, allyl halogenated hydrocarbons, and propargyl halogenated hydrocarbons.

7. The blind hole ultra-fast electroplating leveling agent according to claim 1, characterized in that: The preparation method of the leveling agent comprises the following steps: mixing tertiary amine, glycidyl ether, quaternary ammonium agent and water, reacting at a temperature of 70-90° C. for a reaction time of 12-24 hours, and obtaining the leveling agent after the reaction.

8. The blind hole ultra-fast electroplating leveling agent according to claim 7, characterized in that: The molecular weight of the leveling component in the leveling agent after the reaction is 500-20000 Da, and the pH of the leveling agent is 1.0-3.

0.

9. An electroplating solution, characterized in that The blind hole ultra-speed electroplating leveler comprises the blind hole ultra-speed electroplating leveler according to any one of claims 1 to 8, wherein the mass concentration of the leveler in the electroplating solution is 10-100 ppm.

10. Use of the electroplating solution according to claim 9, characterized in that: Applied to circuit board plating and / or integrated circuit plating, the current density during plating is 3.0-5.0A / dm 2 .

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