Synthesis of a saccharide derivative electroplating leveler and use thereof

Abstract

The application discloses a synthesis method of a sugar derivative electroplating leveler, which comprises the following steps: S1, dissolving a sugar derivative in an organic solvent I, then adding a catalyst, and stirring to form a suspension; adding an epoxy halogen compound, stirring to react, obtaining a reaction product, extracting the reaction product, washing with water for 2-5 times, and evaporating the solvent under reduced pressure to obtain a one-step product; dissolving the one-step product in an organic solvent II, adding a nitrogen-containing compound, stirring to react, evaporating the solvent under reduced pressure, and obtaining a final product, the leveler; the glucose and the epichlorohydrin are reacted under the action of sodium hydride, and the formed leveler is specially applied to high-current-density and high-uniformity copper column electroplating, and the electroplated surface is smooth and uniform, and the crystallization is fine and bright.

Description

Technical Field

[0001] This invention relates to a method for synthesizing a sugar derivative electroplating leveling agent and its application, specifically to C25D, and more particularly to the field of copper electroplating. Background Technology

[0002] Electroplating is a common method for optimizing the surface properties of metallic materials. During processing, metallic materials inevitably develop surface defects such as dents and protrusions. To optimize the surface condition of metallic materials, certain additives are needed to improve the electroplating process. Existing electroplating leveling agents are limited in variety and have incomplete efficacy for all electroplating applications, and their effects are poor at high current densities. Especially for large-area electroplating, process deviations are prone to occur at high current densities. Commonly used leveling agents exhibit low electroplating efficiency, and controlling the leveling effect is difficult. Therefore, developing a leveling agent specifically designed for high current density electroplating solutions is crucial.

[0003] Chinese invention patent CN202210596769.9 discloses a method for preparing high-purity copper sulfate and an electroplating process for copper interconnects. It utilizes hydrogen peroxide oxidation combined with piperidine complexation to dissolve metallic copper. A leveling agent with a positive charge adsorbs onto the substrate surface to suppress protrusions, resulting in copper pillars with excellent uniformity, no cracks, and fine, bright crystals. However, the leveling agent is a composite leveling agent using a combination of multiple substances, making the application process complex. Chinese invention patent CN201610673904.X discloses a soluble anolyte copper plating solution for filling holes. It uses a soluble anode as the anode for electroplating and removes Cu from the plating solution by adding a cuprous sulfate remover. + It can achieve perfect filling of through and blind holes, but it is suitable for low current density and is not suitable for electroplating leveling of copper pillars. Summary of the Invention

[0004] To develop a copper plating leveling agent suitable for high current densities, the first aspect of the present invention provides a method for synthesizing a sugar derivative plating leveling agent, comprising the following steps:

[0005] S1 dissolves the carbohydrate derivative in organic solvent I, then adds the catalyst and stirs to form a suspension;

[0006] S2 is added to an epoxy halogen compound, the mixture is stirred to react, and the reaction product is obtained. The reaction product is extracted, washed with water 2-5 times, and the solvent is removed by vacuum evaporation to obtain the first-step product.

[0007] S3 dissolves the one-step product in organic solvent II, adds a nitrogen-containing compound and stirs the reaction, then evaporates under reduced pressure to remove the solvent, yielding the final product, leveling agent.

[0008] In a preferred embodiment, the hydroxyl molar amount in the sugar derivative is ≥5 mol, and the sugar derivative is selected from one or a combination of monosaccharides, disaccharides, and polysaccharides.

[0009] In a preferred embodiment, the sugar derivative is a monosaccharide, and more preferably, the sugar derivative is glucose.

[0010] In a preferred embodiment, the catalyst is sodium hydride, and the molar ratio of the sugar derivative to sodium hydride is 1:(8-12). The organic solvent I is dimethyl sulfoxide.

[0011] In a preferred embodiment, the molar ratio of the sugar derivative to the epoxide halogen compound is 1:(3-8). More preferably, the molar ratio of the sugar derivative to the epoxide halogen compound is 1:5.

[0012] During the experiment, the applicant discovered that glucose, a monosaccharide derivative, contains numerous terminal hydroxyl groups and a relatively large molecular structure. Introducing epichlorohydrin can yield a molecular configuration containing multiple epoxy groups, which can act as a leveling agent in copper plating solutions, suitable for high-current-density copper plating. However, the terminal hydroxyl groups in glucose show poor reactivity with epichlorohydrin. Introducing sodium hydride can promote the reaction, allowing epichlorohydrin to connect to all end groups of glucose. This is likely because sodium hydride removes the hydrogen from the hydroxyl groups, facilitating electrophilic substitution between carbocations and oxygen atoms, thus shifting the reaction forward and increasing the degree of reactivity. This allows glucose to acquire multiple epoxy groups, enabling it to achieve a suitable leveling effect in high-current-density copper plating.

[0013] In a preferred embodiment, the epoxy halogen compound is selected from one or a combination of several of epichlorohydrin, epifluoropropane, and epibromopropane.

[0014] In a preferred embodiment, the epoxy halogen compound is epichlorohydrin.

[0015] In a preferred embodiment, the extraction solvent is selected from one or a combination of two of ethyl acetate and dichloromethane, preferably ethyl acetate.

[0016] In a preferred embodiment, the molar ratio of the one-step product to the nitrogen-containing compound is 1:(5-10).

[0017] In a preferred embodiment, the molar ratio of the one-step product to the nitrogen-containing compound is 1:(7-9). More preferably, the molar ratio of the one-step product to the nitrogen-containing compound is 1:8.

[0018] During the experiment, the applicant discovered that using a 1:8 molar ratio of the product from the first step to a nitrogen-containing compound increased the yield of the leveling agent final product, reduced the formation of byproducts, and improved the dispersibility of the leveling agent in the copper plating solution, enabling a uniform electroplating reaction. The likely reason is that the glucose structure containing multiple epoxy groups has significant steric hindrance; a 1:8 molar ratio of the first-step product to the nitrogen-containing compound promotes the opening of the epoxy ring, facilitating its connection with the nitrogen-containing structure and resulting in a good nitrogen-containing leveling agent. The prepared leveling agent product contains multiple nitrogen-based structures with uniform dispersion, allowing for uniform deposition of copper ions during electroplating and achieving a good leveling effect.

[0019] In a preferred embodiment, the nitrogen-containing compound is selected from one or a combination of nitrogen-containing chain compounds or nitrogen-containing cyclic compounds.

[0020] As a preferred embodiment, the nitrogen-containing compound has the following structural formula: R1 and R2 are selected from one or more of alkyl, aromatic, alkoxy, hydroxy, aldehyde, and ester groups.

[0021] In a preferred embodiment, the nitrogen-containing compound includes, but is not limited to, one or a combination of several of the following: butylamine, hexylamine, diethylamine, dibutylamine, pyrrolidine, piperidine, piperazine, pyrrole, pyrazole, imidazole, cyclohexylamine, aniline, morpholine, dicyclohexylamine, N-methylcyclohexylamine, and N-methylpiperazine.

[0022] In a preferred embodiment, the nitrogen-containing compound is pyrrolidine.

[0023] In a preferred embodiment, the reaction temperature in step S2 is 40-80℃ and the reaction time is 15-25h.

[0024] In a preferred embodiment, the reaction temperature in step S2 is 45-75℃ and the reaction time is 18-22h.

[0025] In a preferred embodiment, the reaction temperature in step S2 is 50°C and the reaction time is 20 hours.

[0026] In a preferred embodiment, the reaction time in step S3 is 28-32 hours.

[0027] In a preferred embodiment, the reaction time in step S3 is 29-31 hours. Preferably, the reaction time in step S3 is 30 hours.

[0028] In a preferred embodiment, the organic solvent II is selected from one or a combination of methanol, ethanol, propanol, tetrahydrofuran, and ethyl acetate.

[0029] As a preferred embodiment, the synthetic chemical equation for the sugar derivative electroplating leveling agent is as follows:

[0030]

[0031] The second aspect of the present invention provides an application of a method for synthesizing a sugar derivative electroplating leveling agent. The prepared sugar derivative electroplating leveling agent is applied to an electroplating solution. The raw materials and amounts used in the electroplating solution include: CuSO4·5H2O 150-250 g / L, sulfuric acid 40-120 g / L, chloride ions 20-80 mg / L, accelerator 0.2-100 mg / L, inhibitor 0.01-5 g / L, and leveling agent 0.1-500 mg / L.

[0032] In a preferred embodiment, the raw materials and usage amounts of the electroplating solution include: CuSO4·5H2O 170-220 g / L, sulfuric acid 80-110 g / L, chloride ions 40-70 mg / L, accelerator 1-10 mg / L, inhibitor 0.1-1 g / L, and leveling agent 1-100 mg / L.

[0033] In a preferred embodiment, the raw materials and usage amounts for preparing the electroplating solution include: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ion 50mg / L, accelerator 4mg / L, inhibitor 0.5g / L, and leveling agent 25mg / L.

[0034] The applicant found in experiments that when using the leveling agent of this application and when the concentration in the copper plating solution is 0.1-500 mg / L, the surface of the formed copper pillar is horizontal, which can achieve the leveling of the concave holes. However, when the preferred weight ratio is exceeded, the surface of the formed copper pillar is concave or convex, and the leveling effect is not good. The possible reason is that under high current density electroplating, the metal ions in the electroplating solution are controlled by the electrochemical reaction rate and the metal ions are deposited at the concave holes. When the preferred concentration range is exceeded, the deposition of metal ions becomes tilted, which is not conducive to the leveling of the concave holes.

[0035] In a preferred embodiment, the chloride ion is selected from one or a combination of sodium chloride and hydrogen chloride. Preferably, the chloride ion is sodium chloride.

[0036] In a preferred embodiment, the accelerator is selected from one or a combination of sodium polydithiopropane sulfonate (SPS) or 3-mercapto-1-propane sulfonate.

[0037] In a preferred embodiment, the inhibitor is selected from one or a combination of polyethylene glycol (PEG), polypropylene glycol (PPG), or a triblock copolymer of PEG and PPG. Preferably, the molecular weight of the inhibitor is 6000-20000 Da. More preferably, the inhibitor is PEG10000.

[0038] In a preferred embodiment, the electroplating solution is applied to copper pillar electroplating at a high current density of 3-12 ASD, the electroplating temperature is 15-40℃, and the depth of the plated holes is 50-90μm.

[0039] In a preferred embodiment, the electroplating solution is applied to copper pillar electroplating at a high current density of 8-11 ASD, the electroplating temperature is 20-30℃, and the depth of the plated holes is 70-88μm.

[0040] In a preferred embodiment, the electroplating solution is applied to copper pillar electroplating at a high current density of 10 ASD, the electroplating temperature is 25°C, and the depth of the plated holes is 80 μm.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) The method for synthesizing the sugar derivative electroplating leveling agent of the present invention involves glucose and epichlorohydrin reacting in a molar ratio of 1:5 under the action of sodium hydride to form a compound with epoxy groups attached to the end groups, thereby improving the reactivity and promoting the reaction between epichlorohydrin and the end groups of glucose to form a compound containing multiple epoxy groups.

[0043] (2) The method for synthesizing the sugar derivative electroplating leveling agent of the present invention has a molar ratio of one-step product to nitrogen-containing compound of 1:8, which can improve the reaction yield of the leveling agent, reduce the generation of by-products, and improve the uniform dispersion of the leveling agent in copper plating solution.

[0044] (3) The method for synthesizing the sugar derivative electroplating leveling agent of the present invention prepares a leveling agent with a concentration of 0.1-500 mg / L in the electroplating solution, which can make the electroplating solution form a horizontal surface on the copper pillar and achieve leveling of 50-90 μm holes.

[0045] (4) The sugar derivative electroplating leveling agent of the present invention is specifically used in the electroplating of copper pillars with high current density and high uniformity, resulting in a smooth and uniform electroplated surface with fine and bright crystals.

[0046] (5) The method for synthesizing the sugar derivative electroplating leveling agent described in this invention expands the types of leveling agents, reduces the production cost of leveling agents, and is suitable for industrial production applications. Attached Figure Description

[0047] Figure 1-6 The electroplating leveling effect of copper pillars corresponds to Examples 1-6 of the present invention, respectively;

[0048] Figure 7-12 The images are cross-sectional views of the copper pillars after electroplating, corresponding to embodiments 1-6 of the present invention. Detailed Implementation

[0049] Example 1

[0050] A method for synthesizing a sugar derivative electroplating leveling agent includes the following steps:

[0051] S1 Dissolves 2 mol of carbohydrate derivatives in 2 L of organic solvent I, then adds 20 mol of catalyst and stirs to form a suspension;

[0052] S2 was added to 10 mol of epoxy halogen compound, and the reaction was stirred to obtain the reaction product. The reaction product was extracted, washed with water three times, and the solvent was removed by vacuum evaporation to obtain the one-step product with a yield of 90%.

[0053] S3 dissolved 1 mol of the one-step product in 1 L of organic solvent II, added 8 mol of nitrogen-containing compound and stirred the reaction, then evaporated under reduced pressure to remove the solvent, and obtained the final product leveling agent with a yield of 86%.

[0054] The sugar derivative is glucose.

[0055] The catalyst is sodium hydride, and the molar ratio of the sugar derivative to sodium hydride is 1:5. The organic solvent I is dimethyl sulfoxide.

[0056] The epoxy halogen compound is epichlorohydrin. The extraction solvent is ethyl acetate.

[0057] The nitrogen-containing compound is pyrrolidine. The organic solvent II is methanol.

[0058] In step S2, the reaction temperature is 50°C and the reaction time is 20 hours. In step S3, the reaction time is 30 hours.

[0059] The application of a sugar derivative electroplating leveling agent in an electroplating solution, wherein the raw materials and usage of the electroplating solution are: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ion 50mg / L, accelerator 4mg / L, inhibitor 0.5g / L, and leveling agent 25mg / L.

[0060] The chloride ions are sodium chloride. The accelerator is sodium polydisulfide dipropane sulfonate, purchased from Jihechang New Materials (Jingmen) Co., Ltd., with a purity of 99%. The inhibitor is PEG10000.

[0061] The electroplating solution is obtained by mixing the raw materials evenly.

[0062] Example 2

[0063] A method for synthesizing a sugar derivative electroplating leveling agent includes the following steps:

[0064] S1 Dissolves 2 mol of carbohydrate derivatives in 2 L of organic solvent I, then adds 20 mol of catalyst and stirs to form a suspension;

[0065] S2 was added to 10 mol of epoxy halogen compound, and the reaction was stirred to obtain the reaction product. The reaction product was extracted, washed with water three times, and the solvent was removed by vacuum evaporation to obtain the one-step product.

[0066] S3 dissolves 1 mol of the one-step product in 1 L of organic solvent II, adds 8 mol of nitrogen-containing compound and stirs to react, then evaporates under reduced pressure to remove the solvent, obtaining the final product leveling agent.

[0067] The sugar derivative is glucose.

[0068] The catalyst is sodium hydride, and the molar ratio of the sugar derivative to sodium hydride is 1:5. The organic solvent I is dimethyl sulfoxide.

[0069] The epoxy halogen compound is epichlorohydrin. The extraction solvent is ethyl acetate.

[0070] The nitrogen-containing compound is pyrrolidine. The organic solvent II is methanol.

[0071] In step S2, the reaction temperature is 50°C and the reaction time is 20 hours. In step S3, the reaction time is 30 hours.

[0072] The application of a sugar derivative electroplating leveling agent in an electroplating solution, wherein the raw materials and usage of the electroplating solution are: CuSO4·5H2O 220g / L, sulfuric acid 110g / L, chloride ion 70mg / L, accelerator 10mg / L, inhibitor 1g / L, and leveling agent 100mg / L.

[0073] The chloride ions are sodium chloride. The accelerator is 3-mercapto-1-propanesulfonate, purchased from Jihechang New Materials (Jingmen) Co., Ltd., with a purity of 99%. The inhibitor is PEG10000.

[0074] The electroplating solution is obtained by mixing the raw materials evenly.

[0075] Example 3

[0076] An electroplating solution is prepared using the following raw materials and amounts: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ions 50mg / L, accelerator 4mg / L, and inhibitor 0.5g / L.

[0077] The electroplating solution is obtained by mixing the raw materials evenly.

[0078] Example 4

[0079] An electroplating solution is prepared using the following raw materials and dosages: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ion 50mg / L, accelerator 4mg / L, inhibitor 0.5g / L, and leveling agent 0.3mg / L.

[0080] The electroplating solution is obtained by mixing the raw materials evenly.

[0081] Example 5

[0082] A method for synthesizing a sugar derivative electroplating leveling agent, the specific implementation method is the same as in Example 1.

[0083] The application of a sugar derivative electroplating leveling agent in an electroplating solution, wherein the raw materials and usage of the electroplating solution are: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ion 50mg / L, accelerator 4mg / L, inhibitor 0.5g / L, and leveling agent 750mg / L.

[0084] The electroplating solution is obtained by mixing the raw materials evenly.

[0085] Example 6

[0086] A method for synthesizing a sugar derivative electroplating leveling agent, the specific implementation method is the same as in Example 1.

[0087] The application of a sugar derivative electroplating leveling agent in an electroplating solution, wherein the raw materials and usage of the electroplating solution are: CuSO4·5H2O 200g / L, sulfuric acid 100g / L, chloride ion 50mg / L, accelerator 4mg / L, inhibitor 0.5g / L, and leveling agent 550mg / L.

[0088] The electroplating solution is obtained by mixing the raw materials evenly.

[0089] Performance testing

[0090] The electroplating solutions prepared in Examples 1-6 were used to electroplate copper pillars under the conditions of a current density of 10 ASD, an electroplating temperature of 25°C, an electroplating time of 18 min, and a hole depth of 80 μm. The results after electroplating in Examples 1-6 are shown in [Figure 1-6]. Figure 1-6 . Figure 1-6 See the cross-sectional view of the copper pillar. Figure 7-12 .

Claims

1. The application of a sugar derivative electroplating leveling agent, characterized in that, The sugar derivative electroplating leveling agent is applied in the electroplating solution, and the raw materials and usage of the electroplating solution include: CuSO4·5H2O 150-250g / L, sulfuric acid 40-120g / L, chloride ion 20-80mg / L, accelerator 0.2-100mg / L, inhibitor 0.01-5g / L, and leveling agent 0.1-500 mg / L; The method for synthesizing the sugar derivative electroplating leveling agent includes the following steps: S1 dissolves the carbohydrate derivative in organic solvent I, then adds the catalyst and stirs to form a suspension; S2 is added to an epoxy halogen compound, and the mixture is stirred to react and obtain the reaction product. The reaction product is then extracted, washed with water, and the solvent is removed by vacuum evaporation to obtain the first-step product. S3 dissolves the one-step product in organic solvent II, adds a nitrogen-containing compound and stirs the reaction, then evaporates under reduced pressure to remove the solvent, obtaining the final product leveling agent; The sugar derivative is glucose, the epoxy halogen compound is epichlorohydrin, and the nitrogen-containing compound is pyrrolidine. The catalyst is sodium hydride.

2. The application of the sugar derivative electroplating leveling agent according to claim 1, characterized in that, The molar ratio of the sugar derivative to the epoxide halogen compound is 1:(3-8).

3. The application of the sugar derivative electroplating leveling agent according to claim 1, characterized in that, The molar ratio of the one-step product to the nitrogen-containing compound is 1:(5-10).

4. The application of the sugar derivative electroplating leveling agent according to claim 1, characterized in that, In step S2, the reaction temperature is 40-80℃ and the reaction time is 15-25h.

5. The application of the sugar derivative electroplating leveling agent according to claim 1, characterized in that, The organic solvent II is selected from one or a combination of several of methanol, ethanol, propanol, tetrahydrofuran, and ethyl acetate.

Images