Electroplating liquid leveling agent and application thereof

Abstract

The invention provides an electroplating liquid leveling agent and application thereof. The electroplating liquid leveling agent is obtained by sequentially reacting isocyanate halide or isothiocyanate halide with aliphatic diamine and aromatic compounds. The leveling agent provided by the invention is added into an electroplating solution to be used in copper interconnection electroplating, so that the diffusion migration capability can be improved, the adsorption and desorption activity can be balanced, the generation of in-hole filling morphology defects and subsequent reliability risks are avoided, and the electroplating quality and reliability of an electroplating solution composition in hole filling and pattern co-plating are comprehensively improved; the requirements of electroplating filling and pattern co-plating of the opening structure in a certain depth-to-width ratio span range on the wafer and the substrate can be met, and the method has the industrial application advantages of being wide in adaptive scene, easy and convenient to maintain and control, low in production cost and the like; the method can be applied to the fields of integrated circuit manufacturing, integrated circuit packaging, circuit board manufacturing and photovoltaic manufacturing which relate to hole structure copper interconnection electroplating.

Description

Technical Field

[0001] This invention belongs to the field of electronic electroplating technology, specifically relating to an electroplating solution leveling agent and its application. Background Technology

[0002] Electroplating copper is a fundamental and universal technology used in chip manufacturing, advanced packaging, and circuit board manufacturing to achieve horizontal and vertical electrical interconnections. It enables the smooth and uniform filling of openings of different shapes and sizes, such as damascus trenches, redistribution layers, microbumps, through-silicon vias (TSVs), glass vias (SIVs), and micro-blind vias. In addition to copper sulfate, sulfuric acid, and chloride ions, the electroplating solution requires the addition of organic additives such as inhibitors, accelerators, and leveling agents to control the appearance, growth morphology, and material properties of the plating. Among these, the leveling agent is the core component that determines the filling method and performance of the electroplating solution.

[0003] With the miniaturization and integration of integrated circuits, the electroplating filling of copper interconnects on semiconductors and circuit boards has also faced new development challenges: On the one hand, the aspect ratio range of open-hole interconnect structures has been further expanded, including both silicon through-holes with a large aspect ratio of 10:1 or more and redistribution layer patterned holes with a small aspect ratio of less than 0.5:1. It is necessary to develop high-performance electroplating solution leveling agents and electroplating solution formulations to match the design and processing of new interconnect structures; On the other hand, in actual production, it is expected that the same electroplating solution can meet the defect-free filling of interconnect structures of different sizes and types by simply adjusting the component concentration and current density, thereby reducing the cost problems and quality fluctuations caused by switching electroplating solutions. The appearance requirements for electroplating filling of open-hole structures generally include: (1) bright and flat appearance with uniform thickness; (2) as small a depression or protrusion value as possible at the orifice, and coplanarity of different patterns; (3) no voids, gaps or other defects in the orifice; (4) based on the filling quality, the current density should be increased as much as possible and the process control window should be expanded.

[0004] To meet the filling requirements of complex open-hole interconnect structures, the industry has developed various leveling agent molecular systems and electroplating solutions with synergistic effects of multiple leveling agents. However, in the process of technological updates and iterations, how to precisely control the morphology and optimize the performance of electroplating solutions and materials through the design and synthesis of novel additives remains a key focus and challenge in the industry's technological development. Therefore, how to provide an electroplating solution that can adapt to different open-hole types and sizes, precisely control the growth morphology, and ensure material performance has become an urgent problem to be solved. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an electroplating solution leveling agent and its application. The leveling agent provided by this invention, when added to an electroplating solution for copper interconnect electroplating, can improve diffusion and migration capabilities, balance adsorption and desorption activities, avoid defects in the in-hole filling morphology, and mitigate subsequent reliability risks. This comprehensively improves the electroplating quality and reliability of the electroplating solution composition in both open-hole filling and pattern co-plating. Furthermore, it can meet the requirements for electroplating filling and pattern co-plating of open-hole structures with a certain aspect ratio range on wafers and substrates. It has advantages for industrial application, including wide applicability, simple maintenance and management, and low production costs. It can be applied in integrated circuit manufacturing, integrated circuit packaging, circuit board manufacturing, and photovoltaic manufacturing fields involving open-hole copper interconnect electroplating.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides an electroplating solution leveling agent, wherein the electroplating solution leveling agent is obtained by reacting an isocyanate halide or an isothiocyanate halide with an aliphatic diamine and an aromatic compound in sequence;

[0008] The isocyanate halides include aliphatic isocyanate halides or aromatic isocyanate halides;

[0009] The isothiocyanate halides include aliphatic isothiocyanate halides or aromatic isothiocyanate halides.

[0010] The aromatic compounds include tertiary amine compounds containing aromatic rings or aromatic nitrogen heterocyclic compounds.

[0011] The aforementioned specific leveling agents are prepared by sequentially reacting selected raw materials. They possess a first ionic coordinating group (such as urea, thiourea, urea condensate, acylurea, etc.) that regulates the leveling agent's intrapore migration and coverage capabilities; a second coordinating adsorption group (such as ether, alcohol, ketone, ester) that regulates the leveling agent's non-selective adsorption stability at the interface; and a third electrostatic adsorption group (such as quaternary ammonium, conjugated heterocycles) that regulates the leveling agent's selective adsorption intensity at the discharge site. The synergistic effect of these three groups improves the leveling agent's ability to fill various open-hole interconnect structures on electroplated wafers and substrates, avoiding intrapore filling morphology defects and subsequent reliability risks, thus meeting industrial application requirements.

[0012] For example, the electroplating solution leveling agent can be prepared by the following method:

[0013] An intermediate is obtained by reacting an isocyanate halide or isothiocyanate halide with an aliphatic diamine, and then the intermediate is reacted with a monotertiary amine compound to obtain the electroplating solution leveling agent.

[0014] Preferably, the structure of the aliphatic isocyanate halide or aliphatic isothiocyanate halide is as shown in Formula I:

[0015]

[0016] Formula I;

[0017] In the formula, x is selected from fluorine, chlorine, bromine or iodine, y is selected from carbonyl or methylene, z is selected from oxygen or sulfur, and n is an integer from 1 to 5 (1, 2, 3, 4, 5).

[0018] Preferably, the structure of the aromatic isocyanate halide or aromatic isothiocyanate halide is as shown in Formula II:

[0019]

[0020] Formula II;

[0021] In the formula, x1 is selected from fluorine, chlorine, bromine or iodine, z1 is selected from oxygen or sulfur, and R is selected from hydrogen, C1-C6 alkyl or C1-C6 alkoxy.

[0022] Preferably, the isocyanate halide includes any one or a combination of at least two of the following: chloroacetyl isocyanate, p-chlorophenyl isocyanate, m-chlorophenyl isocyanate, o-chlorophenyl isocyanate, 2-chloroethyl isocyanate, 3-chloropropyl isocyanate, 6-chlorohexyl isocyanate, p-bromophenyl isocyanate, m-bromophenyl isocyanate or o-bromophenyl isocyanate, with 3-chloropropyl isocyanate being the most preferred.

[0023] Preferably, the isothiocyanate halide includes any one or a combination of at least two of 2-chloroethyl isothiocyanate, 2-bromoethyl isothiocyanate, 3-bromopropyl isothiocyanate, 3-chloropropyl isothiocyanate, p-chlorophenyl isothiocyanate, m-chlorophenyl isothiocyanate or o-chlorophenyl isothiocyanate, preferably 3-chloropropyl isothiocyanate.

[0024] Preferably, the structure of the aliphatic diamine is as shown in Formula III:

[0025]

[0026] Formula III;

[0027] In the formula, R1 is selected from substituted or unsubstituted C1-C12 alkylene or substituted or unsubstituted C1-C12 alkeneoxy groups, and each R2 is independently selected from any one of imino, methylene, amide, carbonyl, urea, hydrazide or benzenesulfonamide groups.

[0028] Preferably, the substituent is selected from methylene.

[0029] Preferably, R1 and R2 are selected from methylene.

[0030] Preferably, the aliphatic diamine includes any one of propylenediamine, butanediamine, pentanediamine, hexanediamine, 2,2′-(ethylenedioxy)bis(ethylamine), 1,11-diamino-3,6,9-trioxadecane, 4,7,10-trioxa-1,13-tetrazanediamine, polyetheramine, p-phenylenediamine, adipamide, 6-aminohexamethylenediamide, octanoic acid hydrazide, heptanediamide, or adipate dihydrazide, preferably 4,7,10-trioxa-1,13-tetrazanediamine, polyetheramine, or p-phenylenediamine.

[0031] Preferably, the monotertiary amine compound includes an aliphatic monotertiary amine compound or an aromatic monotertiary amine compound.

[0032] Preferably, the structure of the aromatic ring-containing tertiary amine compound is shown in Formula IV:

[0033]

[0034] Formula IV;

[0035] In the formula, R3 is selected from substituted or unsubstituted C6-C16 aryl groups, R4 and R5 are independently selected from any one of substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C1-C6 alkoxy groups, m is an integer from 0 to 3 (0, 1, 2, 3), and when m is 0, the group does not exist here;

[0036] Preferably, the structure of the aromatic nitrogen heterocyclic compound is shown in Formula V:

[0037]

[0038] Formula V;

[0039] It represents any one of the following: aromatic heterocycle, aromatic heterocyclic fused ring, or aromatic heterocyclic combined ring containing one nitrogen atom.

[0040] Preferably, the aromatic compound includes any one or a combination of at least two of pyridine, imidazole, quinoline, isoquinoline, benzimidazole, N,N-dimethylaniline, N,N-dimethylbenzylamine, N,N-dimethylnaphth-1-amine, N,N-dimethylnaphth-2-amine, or N,N-dimethylphenethylamine, and more preferably any one or a combination of at least two of pyridine, quinoline, isoquinoline, or N,N-dimethylbenzylamine.

[0041] The aforementioned specific raw materials can be effectively combined to synergistically improve the leveling agent's ability to fill various open-hole interconnect structures on electroplated wafers and substrates, avoid the generation of defects in the hole filling morphology and subsequent reliability risks, and meet the requirements of industrial applications.

[0042] In a second aspect, the present invention provides an electroplating solution composition comprising water, copper salt, hydrochloric acid, sulfuric acid, inhibitors (e.g., polyethylene glycol, polypropylene glycol, polyethylene glycol-polypropylene glycol copolymer, etc.), accelerators (e.g., sodium 3-mercapto-1-propanesulfonate, sodium polydithiopropanesulfonate, sodium N,N-dimethyldithiocarbamate propanesulfonate, sodium 3-(benzothiazol-2-mercapto)-propanesulfonate, potassium salt of (O-ethyldithiocarbonate)-S-(3-sulfonylpropyl) ester, inner salt of 3-isothiourea propanesulfonate, etc.), and an electroplating solution leveling agent as described above.

[0043] Preferably, the concentration of the electroplating solution leveling agent is 0.5-100 mg / L, such as 0.5 mg / L, 10 mg / L, 20 mg / L, 30 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 70 mg / L, 80 mg / L, 90 mg / L, or 100 mg / L, but is not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0044] Preferably, the electroplating solution composition further includes a second leveling agent, which comprises an oligomeric quaternary ammonium salt obtained by reacting a nitrogen-containing heterocyclic dye (e.g., Janus Green, diazine Black, Alcian Blue, gentian violet, etc.) or a nitrogen-containing heterocyclic dye (e.g., pyrrole, imidazole, pyrazole, pyridine, etc.) with 1,4-butanediol diglycidyl ether.

[0045] Preferably, the concentration of the second leveling agent is 0.5-100 mg / L, such as 0.5 mg / L, 10 mg / L, 20 mg / L, 30 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 70 mg / L, 80 mg / L, 90 mg / L or 100 mg / L, but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0046] Thirdly, the present invention also provides a copper interconnect electroplating method for filling open-hole structures, the electroplating method comprising the following steps:

[0047] The cathode substrate with an open interconnect structure and the metallized anode are immersed in the electroplating solution composition described above, and then plating is applied between the cathode substrate and the anode.

[0048] Preferably, the cathode substrate comprises any one of a silicon-based wafer, an organic substrate, or a glass substrate;

[0049] Preferably, the aspect ratio of the aperture interconnection structure of the cathode substrate is (0.1-4):1, such as 0.1:1, 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or 4:1, but not limited to the values ​​listed above. Other unlisted values ​​within the above range are also applicable.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] (1) The present invention provides a copper interconnect copper electroplating solution composition, wherein the composition contains at least one isocyanate halide or isothiocyanate halide reacting sequentially with an aliphatic diamine derivative and an aromatic ring-containing tertiary amine compound or an aromatic nitrogen heterocyclic compound as a leveling agent. Through the synergy and regulation of multiple functional groups, it can improve its diffusion and migration ability, balance adsorption and desorption activity, avoid the generation of morphological defects in the hole filling and subsequent reliability risks, and comprehensively improve the electroplating quality and reliability of the electroplating solution composition in hole filling and pattern co-plating.

[0052] (2) This invention provides an electroplating method for the copper interconnect electroplating solution composition involved, which can satisfy the electroplating filling and pattern co-plating of open-hole structures with a certain aspect ratio span on wafers and substrates. This invention has advantages in industrial application such as wide applicability, simple maintenance and control, and low production cost, and can be applied to the fields of integrated circuit manufacturing, integrated circuit packaging, circuit board manufacturing and photovoltaic manufacturing involving open-hole copper interconnect electroplating. Attached Figure Description

[0053] Figure 1 This is a cross-sectional focused ion beam imaging of the wafer pattern openings of the electroplated redistribution layer in Example 1;

[0054] Figure 2 This is a cross-sectional focused ion beam imaging of the patterned circuitry on the electroplated redistribution layer wafer in Example 1;

[0055] Figure 3 This is a cross-sectional metallographic section of the micro-blind vias of the electroplated high-density interconnect board in Example 1;

[0056] Figure 4 These are metallographic sections of cross-sections of micro-blind holes in two sets of electroplated high-density interconnect boards, representing comparative examples. Detailed Implementation

[0057] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0058] Example 1

[0059] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0060] 4.4 g of 4,7,10-trioxo-1,13-tridecanediamine and 40 mL of dichloromethane were added to a three-necked flask. Then, a solution of 4.78 g of 3-chloropropyl isocyanate in 30 mL of dichloromethane was added dropwise to the flask at 20 °C. The mixture was stirred at 25 °C in a water bath for 12 hours. The reaction was stopped, and the dichloromethane in the mixture was removed by vacuum distillation to obtain a white solid intermediate 1 (8.72 g, 95% yield). 4.59 g of intermediate 1 and 3.6 g of pyridine were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80 °C and stirred for 24 hours. The reaction was stopped, and the acetonitrile in the mixture was removed by vacuum distillation. The crude product was purified by column chromatography to obtain a pale yellow viscous product (3.12 g, 57% yield).

[0061] Example 2

[0062] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0063] 4.4 g of 4,7,10-trioxo-1,13-tridecanediamine, 1 g of triethylamine, and 40 mL of dichloromethane were added to a three-necked flask. Then, a solution of 5.4 g of 3-chloropropyl isothiocyanate in 30 mL of dichloromethane was added dropwise to the flask at room temperature. The mixture was then stirred at 20 °C for 12 hours. The reaction was stopped, and the solvent was removed by vacuum distillation to obtain a white solid intermediate 1 (6.17 g, 63% yield). 4.9 g of intermediate 2 and 6.68 g of N,N-dimethylbenzylamine were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80 °C and stirred for 24 hours. The reaction was stopped, and the acetonitrile in the mixture was removed by vacuum distillation. The crude product was purified by column chromatography to give a pale yellow viscous product (4.96 g, 72% yield).

[0064] Example 3

[0065] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0066] 4.4 g of 4,7,10-trioxo-1,13-tridecanediamine and 40 mL of dichloromethane were added to a three-necked flask. Then, a solution of 4.78 g of 3-chloropropyl isocyanate in 30 mL of dichloromethane was added dropwise to the flask at room temperature. The mixture was stirred for 12 hours in a water bath at 25°C. The reaction was stopped, and the dichloromethane in the mixture was removed by vacuum distillation to obtain a white solid intermediate 1 (8.72 g, 95% yield). 4.59 g of intermediate 1 and 5.2 g of quinoline were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80°C and stirred for 24 hours. The reaction was stopped, and the acetonitrile in the mixture was removed by vacuum distillation. The crude product was purified by column chromatography to obtain a pale yellow viscous product (5.8 g, 81% yield).

[0067] Example 4

[0068] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0069] 2.72 g of p-phenylenediamine and 40 mL of dichloromethane were added to a three-necked flask. Then, a solution of 4.78 g of 3-chloropropyl isocyanate in 30 mL of dichloromethane was added dropwise to the flask at room temperature. The mixture was stirred for 12 hours in a water bath at 25°C. The reaction was stopped, and the dichloromethane in the mixture was removed by vacuum distillation to obtain a white solid intermediate 3 (7.3 g, 97% yield). 6.16 g of intermediate 3 and 5.34 g of N,N-dimethylbenzylamine were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80°C and stirred for 24 hours. The reaction was stopped, and the acetonitrile in the mixture was removed by vacuum distillation. The crude product was purified by column chromatography to obtain a pale yellow viscous product (6.5 g, 79% yield).

[0070] Example 5

[0071] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0072] 4.6 g of polyetheramine (commercial product D230) and 40 mL of dichloromethane were added to a three-necked flask. Then, a 30 mL solution of dichloromethane containing 4.78 g of 3-chloropropyl isocyanate was added dropwise to the flask at room temperature. The mixture was stirred for 12 hours in a water bath at 25°C. The reaction was stopped, and the dichloromethane was removed from the mixture by vacuum distillation to obtain a white solid intermediate 4 (8.7 g, 92% yield). 4.7 g of intermediate 4 and 6 g of isoquinoline were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80°C and stirred for 24 hours. The reaction was stopped, and the acetonitrile was removed from the mixture by vacuum distillation. The crude product was purified by column chromatography to obtain a pale yellow viscous product (5.1 g, 69% yield).

[0073] Example 6

[0074] This embodiment provides an electroplating solution leveling agent, the preparation method of which is as follows:

[0075] 2.72 g of p-phenylenediamine, 1 g of triethylamine, and 40 mL of dichloromethane were added to a three-necked flask. Then, a solution of 5.4 g of 3-chloropropyl isothiocyanate in 30 mL of dichloromethane was added dropwise to the flask at room temperature. The mixture was stirred at 20 °C for 12 hours. The reaction was stopped, and the solvent was removed by vacuum distillation to obtain a white solid intermediate 3 (5.76 g, 71% yield). 4.06 g of intermediate 3 and 5.34 g of N,N-dimethylbenzylamine were added to the three-necked flask, followed by the addition of 10 mL of acetonitrile. The mixture was heated to 80 °C and stirred for 24 hours. The reaction was stopped, and the acetonitrile in the mixture was removed by vacuum distillation. The crude product was purified by column chromatography to give a pale yellow viscous product (4.12 g, 68% yield).

[0076] Example 7

[0077] This embodiment provides an electroplating solution leveling agent. The preparation method is the same as in Example 1, except that 3-chloropropyl isocyanate is replaced with an equimolar amount of 3-chloropropyl isothiocyanate.

[0078] The final product was a colorless, viscous product (3.03 g, yield 75%).

[0079] Example 8

[0080] This embodiment provides an electroplating solution leveling agent. The preparation method is the same as in Example 1, except that 3-chloropropyl isocyanate is replaced with an equimolar amount of chloroacetyl isocyanate.

[0081] The final product was a pale yellow color (2.97 g, yield 61%).

[0082] Example 9

[0083] This embodiment provides an electroplating solution leveling agent. The preparation method is the same as in Example 1, except that 4,7,10-trioxo-1,13-tetanediamine is replaced with an equimolar amount of propylenediamine.

[0084] The final product was a colorless, viscous product (2.65 g, yield 57%).

[0085] Example 10

[0086] This embodiment provides an electroplating solution leveling agent. The preparation method is the same as in Example 1, except that pyridine is replaced with an equimolar amount of benzimidazole.

[0087] The final product was a yellow product (3.01 g, 68%).

[0088] Effect evaluation:

[0089] Prepare electroplating solution composition 1 according to the following formula and mix evenly: 1500 mL pure water, 200 g / L copper sulfate pentahydrate, 56 ml / L 98wt% concentrated sulfuric acid, 0.15 ml / L 37wt% hydrochloric acid, 2 mg / L sodium polydisulfide dipropane sulfonate as the accelerator, 400 mg / L polyethylene glycol (weight average molecular weight 20000) as the inhibitor, and 10 mg / L electroplating solution leveling agent provided in the example above as the leveling agent.

[0090] Electroplating experiments were conducted in a Harlem tank using the above-mentioned electroplating solution composition 1 according to the following method: The cathode was a redistribution layer wafer with a cutting size of 25×25 mm. It underwent multiple photolithography and sputtering processes to simultaneously form a second-order open-cell structure with a lower layer of 30×5 μm (aperture × depth) and an upper layer of 50×10 μm (aperture × depth). The upper layer also had a 20 / 20 μm (linewidth / spacing) circuit pattern. The anode was a phosphor bronze plate (phosphorus content 0.05 wt%) with a cutting size of 120×60 mm. The volume of the electroplating solution composition was 1500 mL, the temperature was 25°C, and air stirring was applied at 7.2 L / min. The applied current density was 3 A / dm³. 2 The electroplating time was 18 minutes. After electroplating, the bare wafer was rinsed with pure water and treated with dimethyl sulfoxide to remove the upper photoresist layer. Then, a focused ion beam was used to cut the cross-section, and the range values ​​of filling defects, hole center, and edge were observed (range value = center plating height - edge plating height). Figure 1-2 This is a focused ion beam image of the cross-section of the wafer pattern openings and lines of the electroplated redistribution layer in Example 1.

[0091] The results are as follows (Comparative Example 1 uses Janus Green B (JGB) as a leveling agent instead of the leveling agent in the electroplating solution):

[0092]

[0093] From the above table and Figure 1-2 As can be seen, the leveling agent prepared in Examples 1-7 of this invention can achieve defect-free (core-wrapped or incompletely filled) filling of second-order vias and their coplanar lines in the redistribution layer wafer bare die with an aspect ratio of 0.17:1. The via openings are slightly concave or slightly convex, and the lines are all slightly convex. The difference between the center and edge of the via is about -0.4~0.5 μm, which meets the requirements of the redistribution layer filling technology for wafer-level packaging. However, in Comparative Example 1, the difference between the center and edge of the via is about -4 μm, and it is not fully filled and leveled. The opening filling effect does not meet the requirements of the redistribution layer filling technology for wafer-level packaging.

[0094] Then, electroplating solution composition 2 was prepared according to the following formula and mixed evenly: 1500 mL of pure water, 220 g / L of copper sulfate pentahydrate, 28 ml / L of 98 wt% concentrated sulfuric acid, 0.15 ml / L of 37 wt% hydrochloric acid, 2 mg / L of sodium polydisulfide dipropane sulfonate as the accelerator, 400 mg / L of polyethylene glycol (weight average molecular weight 20000) as the inhibitor, and 15 mg / L of electroplating solution leveling agent provided in Examples 1-3 and 7-10, or a mixture of 5 mg / L of electroplating solution leveling agent provided in Examples 1-3 and 10 mg / L of commercially available leveling agent.

[0095] Electroplating experiments were conducted in a Harlem tank using the above-mentioned electroplating solution composition 2 according to the following method: The cathode was a high-density interconnect board sample, cut to size 100×50 mm (length×width), which underwent electroless copper plating and flash copper plating to form an open structure of 100×75 μm (pore diameter×pore depth); the anode was a phosphor bronze plate (phosphorus content 0.05 wt%), cut to size 120×60 mm (length×width); the volume of the electroplating solution composition was 1500 ml, the temperature was 25℃, air stirring was applied at 7.2 L / min, and the applied current density was 1.8 A / dm³. 2 The electroplating time was 43 min. After electroplating, the sample was rinsed with pure water and dried with cold air. Then, cross-sectional metallographic sections of the micro-blind holes were prepared to observe the filling defects, the thickness of the surface copper (excluding the approximately 10 μm of bottom copper), and the value of the central depression. Figure 3-4 The images shown are cross-sectional metallographic photographs of micro-blind vias in the electroplated high-density interconnect boards of Example 1 and Comparative Example 2, respectively. The results are as follows (the leveling agents in Comparative Examples 2-4 were replaced with equal amounts of Janus Green B (JGB), imidazole-epoxychloropropane copolymer (IMEP), and methylene blue (MB), respectively):

[0096]

[0097] From the above table and Figure 3 It can be seen that the leveling agent prepared in Examples 1-3 of the present invention, and the mixture of the leveling agent prepared in Examples 1-3 and the commercially available leveling agent, can achieve defect-free filling when used for electroplating micro blind holes with an aspect ratio of 0.75 in high-density interconnect boards. The hole opening is basically flat, the surface copper thickness is about 15 μm, and the center depression value is -3.9~-5.7 μm, which meets the blind hole filling technology requirements of circuit board manufacturing.

[0098] From the above table and Figure 4As can be seen, when Comparative Examples 2-4 used JGB, IMEP, and MB as the sole leveling agents to electroplate high-density interconnect micro blind vias with an aspect ratio of 0.75, the via openings exhibited a concave morphology, with a copper thickness of approximately 15 μm and a central concavity of -18.1 to 25.6 μm, failing to fill and level the vias. This does not meet the blind via filling plating technology requirements for circuit board manufacturing and shows significant differences from Examples 1-3 and their mixtures.

[0099] Furthermore, the data above shows that by using specific raw materials, the present invention can further reduce the porosity value and effectively control the range of depression values, thereby improving the product performance.

[0100] The applicant declares that this invention illustrates the electroplating solution leveling agent and its application through the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials of this invention, addition of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

[0101] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0102] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

Claims

1. A leveling agent for electroplating solutions, characterized in that, The electroplating solution leveling agent is obtained by reacting isocyanate halides or isothiocyanate halides with aliphatic diamines and aromatic compounds in sequence; The isocyanate halides include aliphatic isocyanate halides or aromatic isocyanate halides; The isothiocyanate halides include aliphatic isothiocyanate halides or aromatic isothiocyanate halides; The aromatic compounds include tertiary amine compounds containing aromatic rings or aromatic nitrogen heterocyclic compounds.

2. The electroplating solution leveling agent according to claim 1, characterized in that, The structure of the aliphatic isocyanate halide or aliphatic isothiocyanate halide is shown in Formula I: Formula I; In the formula, x is selected from fluorine, chlorine, bromine or iodine, y is selected from carbonyl or methylene, z is selected from oxygen or sulfur, and n is an integer from 1 to 5; Preferably, the structure of the aromatic isocyanate halide or aromatic isothiocyanate halide is as shown in Formula II: Formula II; In the formula, x1 is selected from fluorine, chlorine, bromine or iodine, z1 is selected from oxygen or sulfur, and R is selected from hydrogen, C1-C6 alkyl or C1-C6 alkoxy.

3. The electroplating solution leveling agent according to claim 1 or 2, characterized in that, The isocyanate halide includes any one or a combination of at least two of the following: chloroacetyl isocyanate, p-chlorophenyl isocyanate, m-chlorophenyl isocyanate, o-chlorophenyl isocyanate, 2-chloroethyl isocyanate, 3-chloropropyl isocyanate, 6-chlorohexyl isocyanate, p-bromophenyl isocyanate, m-bromophenyl isocyanate or o-bromophenyl isocyanate, preferably 3-chloropropyl isocyanate; Preferably, the isothiocyanate halide includes any one or a combination of at least two of 2-chloroethyl isothiocyanate, 2-bromoethyl isothiocyanate, 3-bromopropyl isothiocyanate, 3-chloropropyl isothiocyanate, p-chlorophenyl isothiocyanate, m-chlorophenyl isothiocyanate or o-chlorophenyl isothiocyanate, preferably 3-chloropropyl isothiocyanate.

4. The electroplating solution leveling agent according to any one of claims 1-3, characterized in that, The structure of the aliphatic diamine is shown in Formula III: Formula III; In the formula, R1 is selected from substituted or unsubstituted C1-C12 alkylene or substituted or unsubstituted C1-C12 alkeneoxy groups, and each R2 is independently selected from any one of imino, methylene, amide, carbonyl, urea, hydrazide or benzenesulfonamide groups; Preferably, the substituent is selected from methyl; Preferably, R1 and R2 are selected from methylene.

5. The electroplating solution leveling agent according to claim 4, characterized in that, The aliphatic diamine includes any one of propylenediamine, butanediamine, pentanediamine, hexanediamine, 2,2′-(ethylenedioxy)bis(ethylamine), 1,11-diamino-3,6,9-trioxadecane, 4,7,10-trioxa-1,13-tetrazanediamine, polyetheramine, p-phenylenediamine, adipamide, 6-aminohexamethylenediamine, octanoic acid hydrazide, heptane dihydrazide, or adipate dihydrazide, preferably 4,7,10-trioxa-1,13-tetrazanediamine, polyetheramine, or p-phenylenediamine.

6. The electroplating solution leveling agent according to any one of claims 1-5, characterized in that, The structure of the aromatic ring-containing tertiary amine compound is shown in Formula IV: Formula IV; In the formula, R3 is selected from substituted or unsubstituted C6-C16 aryl groups, R4 and R5 are independently selected from any one of substituted or unsubstituted C1-C6 alkyl groups and substituted or unsubstituted C1-C6 alkoxy groups, m is an integer from 0 to 3, and when m is 0, the group does not exist here; Preferably, the structure of the aromatic nitrogen heterocyclic compound is shown in Formula V: Formula V; It represents any one of the following: aromatic heterocycle, aromatic heterocyclic fused ring, or aromatic heterocyclic combined ring containing one nitrogen atom.

7. The electroplating solution leveling agent according to claim 5 or 6, characterized in that, The aromatic compound includes any one or a combination of at least two of pyridine, imidazole, quinoline, isoquinoline, benzimidazole, N,N-dimethylaniline, N,N-dimethylbenzylamine, N,N-dimethylnaphth-1-amine, N,N-dimethylnaphth-2-amine, or N,N-dimethylphenethylamine, preferably any one or a combination of at least two of pyridine, quinoline, isoquinoline, or N,N-dimethylbenzylamine.

8. An electroplating solution composition, characterized in that, The electroplating solution composition includes water, copper salt, hydrochloric acid, sulfuric acid, inhibitor, accelerator, and electroplating solution leveling agent according to any one of claims 1-7.

9. The electroplating solution composition according to claim 8, characterized in that, The concentration of the electroplating solution leveling agent is 0.5-100 mg / L; Preferably, the electroplating solution composition further includes a second leveling agent, which comprises a nitrogen-containing heterocyclic dye or an oligomeric quaternary ammonium salt obtained by reacting a nitrogen-containing heterocyclic dye with 1,4-butanediol diglycidyl ether. Preferably, the concentration of the second leveling agent is 0.5-100 mg / L.

10. A method for electroplating copper interconnects with a filled open-hole structure, characterized in that, The electroplating method includes the following steps: The cathode substrate and anode, which have an open interconnect structure and are metallized, are immersed in the electroplating solution composition of claim 8 or 9, and then plating is applied between the cathode substrate and the anode. Preferably, the cathode substrate comprises any one of a silicon-based wafer, an organic substrate, or a glass substrate; Preferably, in the aperture interconnection structure of the cathode substrate, the aspect ratio is (0.1-4):1.

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