Composition and its application, and leveling agent and its preparation method

Abstract

A composition is provided, the composition comprising a metal ion source and a compound of formula (I): R1-S-(R3-O) m -(R2-O) n -R2-(O-R3) m -S-R1 and a leveling agent represented by the formula (I): In formula (I), the two R1 terms are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups, the two R2 terms are independently substituted or unsubstituted linear alkylene, the two R3 terms are independently substituted or unsubstituted linear alkylene, m is 0 or 1, and n is an integer of 2 or greater. The composition is applied to fill metal into through-holes of electronic substrates, and through-holes with different openings are uniformly filled, resulting in a reduction in the thickness of the surface metal layer and a reduction in the dimple value.

Description

[Technical Field]

[0001] This application claims priority to Chinese Patent Application No. 202211056305.5, entitled "Composition and Application Thereof, as well as Leveling Agent and Preparation Method Thereof," filed with the State Intellectual Property Office of the People's Republic of China on August 31, 2022, the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION Embodiments of the present application relate to the field of metal electroplating technology, and in particular to compositions and their applications, as well as leveling agents and methods for their preparation. [Background technology]

[0003] Electronic substrates include common substrates, printed circuit boards, and package substrates. Package substrates are the core material for mounting chips and can provide functions such as electrical connection, support and protection, signal distribution, and chip heat dissipation. Through holes (including plated through holes, blind via holes, and buried via holes) are the most typical interconnection structures for package substrates. Copper electroplating technology can perform filling or shape-retaining deposition of interconnection structures such as plated through holes, blind via holes, and buried via holes, resulting in high-quality electroplated copper layers that can meet the electrical interconnection requirements of package substrates. Figures 1A and 1B show a blind via hole without copper filling and a blind via hole with copper filling, respectively. Here, 1 is the blind via hole. Summary of the Invention [Problem to be solved by the invention]

[0004] Electroplated copper layers provide electrical connection channels for package substrates. Copper plating is a key process for manufacturing package substrates. To improve interconnect reliability and product yield and meet the process requirements for fine wiring, the following requirements must be met when filling plated through holes, blind via holes, and buried via holes with copper electroplating: (1) Small copper plating thickness: Small copper plating thickness facilitates the formation of fine wiring, effectively shortens electroplating time, and improves production efficiency. (2) The ability to deposit into different apertures, such as deposition into small holes with high aspect ratios (aspect ratio > 1) and large holes (opening range of 125 μm to 150 μm). (3) Small dimple value, high hole filling rate, uniformity of electroplating (>90%), and less impurities in the plating layer.

[0005] To better meet the aforementioned technical demands, electroplating chemicals are usually improved in the industry, and leveling agents are considered to be a key factor for the improvement. [Means for solving the problem]

[0006] In view of this, an embodiment of the present application provides a composition, which includes a leveling agent with a special structure, and is used to fill interconnect structures in electronic circuit boards, thereby more uniformly filling through-holes with different openings and reducing the thickness and dimple value of the surface metal layer, thereby improving the reliability of interconnections and the yield of electronic products.

[0007] Specifically, in a first aspect of the present embodiment, a composition is provided, the composition being an electroplating composition, the electroplating composition comprising a metal ion source and a leveling agent represented by formula (I): R1-S-(R3-O) m -(R2-O) n-R2-(O-R3) m -S-R1 formula (I). In formula (I), The two R1 moieties are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups; The two R2 terms are independently substituted or unsubstituted linear alkylene; The two R3 terms are independently substituted or unsubstituted linear alkylene; m is 0 or 1, and n is an integer of 2 or more.

[0008] Electroplating compositions provided in embodiments of the present application include a leveling agent having a specific structure. The leveling agent has an ether oxygen chain: (R-O) m -(R2-O) n -R2-(O-R3) m and a nitrogen-containing heterocyclic group connected to both ends of the ether oxygen chain via a sulfur bond. Electroplating compositions containing leveling agents with specific structures are used as electroplating metals to fill through-holes in electronic substrates. The leveling agents are selectively adsorbed in areas of high current density, thereby better adjusting the current density distribution on the cathode surface during the electroplating process. Furthermore, the leveling agents are convection-dependent, resulting in a high concentration in areas of high convection strength. Finally, metal deposition in areas corresponding to high current density is effectively suppressed, resulting in a uniform metal plating layer. In the present application, electroplating compositions containing leveling agents with specific structures are used to simultaneously fill through-holes with different openings, reducing copper plating thickness and dimple values, and improving the uniformity of electroplating across electronic circuit boards. This facilitates the production of fine wiring, promotes improved reliability of electronic products, and allows for a simple, low-cost process to better meet the manufacturing requirements for high-density interconnected electronic substrates. Furthermore, the molecular structure of the leveling agents is stable, making it easier to suppress the amount of impurities in the metal plating layer. The leveling agent may also be prepared using simple ingredients and processes.

[0009] In an embodiment of the present application, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of substituted or unsubstituted pyrrole group, substituted or unsubstituted imidazole group, substituted or unsubstituted pyridine group, substituted or unsubstituted pyrimidine group, substituted or unsubstituted triazole group, substituted or unsubstituted tetrazole group, substituted or unsubstituted thiozole group, substituted or unsubstituted benzopyrrole group, substituted or unsubstituted benzimidazole group, substituted or unsubstituted benzopyridine group, substituted or unsubstituted benzopyrimidine group, substituted or unsubstituted benzotriazole group, substituted or unsubstituted benzothiazole group, substituted or unsubstituted bipyridine group, and substituted or unsubstituted triazobenzene group.The substituted or unsubstituted nitrogen-containing heterocyclic group is useful for the leveling agent to obtain good leveling properties.

[0010] In embodiments of the present application, the substituents in the substituted nitrogen-containing heterocyclic group include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

[0011] In an embodiment of the present application, the two R2 terms are independently substituted or unsubstituted linear alkylenes having from 2 to 10 carbon atoms, and the two R3 terms are independently substituted or unsubstituted linear alkylenes having from 2 to 10 carbon atoms.

[0012] In an embodiment of the present application, the substituted linear alkylene includes linear alkylene substituted with hydroxyl.

[0013] In an embodiment of the present application, the concentration of the leveling agent represented by formula (I) in the electroplating composition ranges from 0.01 ppm to 1000 ppm. The concentration of the leveling agent in the electroplating composition is controlled within a suitable range to facilitate an appropriate deposition rate, more effectively fill through-holes with different openings simultaneously, reduce the thickness of the surface metal layer and the dimple value, and improve the uniformity of the electroplating across the entire electronic circuit board. This facilitates the production of fine wiring and promotes the improvement of the reliability of electronic products.

[0014] In embodiments of the present application, the plating composition further comprises at least one acid, wherein the at least one acid comprises one or more of sulfuric acid and methanesulfonic acid.

[0015] In embodiments of the present application, the concentration of the at least one acid in the electroplating composition ranges from 1 g / L to 300 g / L. A suitable acid system and suitable acid concentration help to obtain an adequate electroplating rate.

[0016] In an embodiment of the present application, the electroplating composition further comprises one or more of an accelerator, an inhibitor, and an inorganic additive, which cooperate with each other to simultaneously better fill through-holes with different openings, thereby reducing the thickness of the surface metal layer and the dimple value.

[0017] In an embodiment of the present application, the accelerator comprises one or more of sodium 3-mercapto-1-propanesulfonate (MPS), sodium polyanetholesulfonate (SPS), and sodium N,N-dimethyl-dithioformamidopropylenesulfonate (DPS), and the concentration of the accelerator in the electroplating composition ranges from 0.01 ppm to 500 ppm. The addition of the accelerator achieves a depolarization effect, promotes metal deposition, and refines grains in the metal layer.

[0018] In an embodiment of the present application, the inhibitor comprises one or more of polyethylene glycol (PEG), polypropylene glycol (PPG), block copolymer PEO-PPO-PEO, block copolymer PPO-PEO-PPO, random copolymer of EO and PO, and propylene glycol block polyether, and the concentration of the inhibitor in the electroplating composition ranges from 1 ppm to 2000 ppm. The addition of the inhibitor inhibits the growth rate of the surface metal and promotes the formation of a thin surface metal layer after electroplating is completed.

[0019] In an embodiment of the present application, the inorganic additive comprises chloride anions, and the concentration of chloride anions in the electroplating composition ranges from 0.1 ppm to 100 ppm. The addition of chloride ions can make the plated crystals dense and fine.

[0020] In an embodiment of the present application, the metal ion source includes any one of a copper ion source, a nickel ion source, a tin ion source, a cobalt ion source, a ruthenium ion source, and a silver ion source. When a metal layer is pre-deposited, it is understood that the metal ion source in the electroplating composition includes a metal ion source corresponding to the metal element in the pre-deposited metal layer. For example, when a metallic copper layer is pre-deposited, the metal ion source includes a copper ion source.

[0021] In an embodiment of the present application, the copper ion source comprises one or more of copper sulfate pentahydrate and copper methanesulfonate, and the concentration of the copper ion source in the electroplating composition ranges from 1 g / L to 120 g / L of copper ions. The concentration of the copper ion source is controlled within a suitable range to help maintain a balance between the deposition rate, brightness, and flatness of the resulting copper plating layer.

[0022] In a second aspect of the present embodiment, there is provided the application of the electroplating composition of the first aspect to electroplating metals.

[0023] In embodiments of the present application, the electroplated metal includes any one of electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, and electroplated silver and silver alloys.

[0024] In an embodiment of the present application, the electroplated metal comprises a metal electroplated into a through-hole of an electronic substrate to perform a metal fill.

[0025] In a third aspect of the present embodiment, there is provided the application of a compound of formula (I) to electroplating metals: R1-S-(R3-O) m -(R2-O) n -R2-(O-R3) m -S-R1 formula (I) In formula (I), the two R1 terms are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups, the two R2 terms are independently substituted or unsubstituted linear alkylene, the two R3 terms are independently substituted or unsubstituted linear alkylene, m is 0 or 1, and n is an integer of 2 or greater.

[0026] In an embodiment of the present application, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyridine group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

[0027] In embodiments of the present application, substituents in a substituted nitrogen-containing heterocyclic group include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

[0028] In an embodiment of the present application, the two R2 terms are independently substituted or unsubstituted linear alkylene having a carbon number ranging from 2 to 10, and the two R3 terms are independently substituted or unsubstituted linear alkylene having a carbon number ranging from 2 to 10.

[0029] In embodiments of the present application, substituted linear alkylene includes linear alkylene substituted with hydroxyl.

[0030] In a fourth aspect of the present embodiment, a leveling agent is provided, the leveling agent having the general structural formula shown in formula (II): R1-S-(R3-O) m -(R2-O) n -R2-(O-R3) m-S-R1 formula (II) wherein in formula (II), two R1's are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups, two R2's are independently substituted or unsubstituted chain alkylene, two R3's are independently substituted or unsubstituted chain alkylene, m is 0 or 1, and n is an integer of 2 or more.

[0031] When m=0, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

[0032] When m=1, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

[0033] Substituents in said substituted nitrogen-containing heterocyclic groups include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

[0034] In an embodiment of the present application, in formula (II), the two R2 terms are independently substituted or unsubstituted linear alkylene having a carbon number ranging from 2 to 10, and the two R3 terms are independently substituted or unsubstituted linear alkylene having a carbon number ranging from 2 to 10.

[0035] In embodiments of the present application, substituted linear alkylene includes linear alkylene substituted with hydroxyl.

[0036] In a fifth aspect of the present embodiment, there is provided a method for preparing the leveling agent according to the fourth aspect.

[0037] The method comprises the steps of: n The method includes the step of substituting -R2-OH with a p-toluenesulfonyl group or an epoxy group, and then reacting the resulting compound with a mercapto or a nitrogen-containing heterocyclic compound containing a carbon-sulfur double bond to obtain a leveling agent, wherein in compound A, the two R2 terms are independently substituted or unsubstituted linear alkylene, and n is an integer of 2 or greater.

[0038] In a sixth aspect of the present embodiment, there is provided an electroplating composition comprising the leveling agent of the fourth aspect of the present embodiment.

[0039] In a seventh aspect of the present embodiment, there is provided the application of the leveling agent of the fourth aspect or the electroplating composition of the sixth aspect to a metal electroplating process.

[0040] In embodiments of the present application, the electroplated metal includes any one of electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, and electroplated silver and silver alloys.

[0041] In an embodiment of the present application, the electroplated metal comprises a metal electroplated into a through-hole of an electronic substrate to perform a metal fill.

[0042] In an eighth aspect of the present embodiment, a metal electroplating method is provided.

[0043] The method includes contacting a substrate to be electroplated with the electroplating composition of the first aspect or the electroplating composition of the sixth aspect, and applying a current to the substrate to be electroplated for electroplating, thereby forming a metal layer on the substrate to be electroplated.

[0044] In an embodiment of the present application, a through-hole is provided in a substrate to be electroplated, and the metal layer includes an inner hole filling layer that fills the through-hole and a surface deposition layer that is deposited around the through-hole.

[0045] In the present embodiment, the through-holes have a diameter of 10 μm to 200 μm and a depth of 20 μm to 200 μm.

[0046] In the embodiment of the present application, the electroplating process conditions are as follows: the electroplating temperature is in the range of 10°C to 40°C, the current density is in the range of 0.5 ASD to 5 ASD, and the electroplating time is in the range of 30 minutes to 300 minutes.

[0047] In a ninth aspect of the present application, there is further provided an electronic substrate, the electronic substrate including a substrate layer and a metal layer disposed on the substrate layer, the metal layer being provided by electroplating the electroplating composition of the first aspect of the present application or the electroplating composition of the sixth aspect of the present application, or formed by using the metal electroplating method of the eighth aspect of the present application.

[0048] In one embodiment of the present application, there is further provided an electronic device, which uses the electronic board according to the ninth aspect of the embodiment of the present application. [Brief explanation of the drawings]

[0049] [Figure 1A] FIG. 1 shows a blind via hole that is not filled with copper. [Figure 1B] FIG. 1 illustrates a copper-filled blind via hole. [Figure 2] FIG. 1 is a diagram of electroplated copper. [Figure 3] FIG. 1 is a diagram of dimple values. [Figure 4] 1 is a diagram of a structure of an electronic substrate 100 according to an embodiment of the present application. [Figure 5] FIG. 1 shows the hydrogen nuclear magnetic resonance spectrum of the prepared leveling agent 1 according to Example 1 of the present application. [Figure 6] FIG. 1 shows the hydrogen nuclear magnetic resonance spectrum of the prepared leveling agent 1 according to Example 1 of the present application. [Figure 7] FIG. 1 shows the carbon nuclear magnetic resonance spectrum of prepared leveling agent 1 according to Example 1 of the present application. [Figure 8] FIG. 1 shows linear sweep voltammetry curves of Leveling Agent 1, Leveling Agent 2, and Leveling Agent 3. [Figure 9] FIG. 1 is a diagram showing cyclic voltammetry curves of Leveling Agent 1, Leveling Agent 2, and Leveling Agent 3. [Figure 10A]1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 1, respectively. [Figure 10B] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 1, respectively. [Figure 10C] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 1, respectively. [Figure 10D] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 1, respectively. [Figure 11A] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 2, respectively. [Figure 11B] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 2, respectively. [Figure 11C] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 2, respectively. [Figure 11D] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Example 2, respectively. [Figure 12A]1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 1. [Figure 12B] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 1. [Figure 12C] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 1. [Figure 12D] 1A and 1B show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 1. [Figure 13A] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 2. [Figure 13B] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 2. [Figure 13C] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 2. [Figure 13D] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 2. [Figure 14A]10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 3. [Figure 14B] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 3. [Figure 14C] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 3. [Figure 14D] 10A-10C show the results of filling blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm via electroplating using the copper electroplating solution in Comparative Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0050] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings.

[0051] Electronic substrates include common substrates, printed circuit boards, package substrates, etc. Package substrates are the core material for mounting chips and can provide functions such as electrical connection, support and protection, signal distribution, and chip heat dissipation. Through holes (including plated through holes, blind via holes, and buried via holes) are the most typical interconnection structures of package substrates. Copper electroplating technology performs filling or shape-retaining deposition of interconnection structures such as plated through holes, blind via holes, and buried via holes, resulting in high-quality electroplated copper layers that can meet the electrical interconnection requirements of package substrates.

[0052] Electroplating is a method of electrochemically reducing metal ions to metal and depositing the metal on the surface of a metal or nonmetallic product to form a smooth, dense metal plating layer that meets required specifications. In electroplating, a conductive substrate is used as the cathode, and a metal is obtained through a reduction reaction and deposited on the surface of the conductive substrate (the cathode is the electrode that obtains electrons, i.e., the electrode where the reduction reaction occurs). A soluble or insoluble anode undergoes a metal dissolution reaction or an oxygen evolution reaction (the anode is the electrode where the electrolyte can perform the oxidation reaction), and the electroplating solution is used as a conductive loop for the electrolyte. Figure 2 shows a diagram of electroplated copper. In copper electroplating technology for package substrates, the cathode plating component is the package substrate to be electroplated. Conductive metallic copper is deposited into the required interconnect structure through a metal deposition reaction at the cathode. However, in the metal electroplating process, the package substrate to be electroplated at the cathode is usually an irregular plating component, and various interconnect structures containing different openings are arranged based on the required specifications. According to the law of initial current density distribution, regions that are geometrically far from the anode (e.g., the bottom of a blind via hole) have a low current density, while regions that are geometrically close to the anode (e.g., the top of a blind via hole) have a high current density. In this case, the current density difference causes uneven filling of the interconnect structure, making it difficult to obtain a uniform metal plating layer, maintaining a low dimple value, and even filling in some wiring structures. As shown in FIG. 3, the dimple value = B-A, where B is the distance between the top surface of the copper surface and the bottom of the blind via hole, and A is the distance between the bottom of the dimple and the bottom of the blind via hole. In one embodiment of the present application, an electroplating composition is provided for forming a uniform plating layer and achieving a superfilled or shape-retaining filled structure in the interconnect structure through deposition. The electroplating composition includes a leveling agent having a specific structure, and the addition of the leveling agent helps improve the uniformity of electroplating across an electronic circuit board, can fill through holes with different aspect ratios, and can reduce the thickness and dimple value of the surface metal layer.

[0053] The electroplating composition provided in the embodiments of the present application may be used as an electroplating solution for obtaining a metal layer through electroplating deposition. The electroplating composition includes a metal ion source and a leveling agent represented by formula (I): R1-S-(R3-O) m -(R2-O) n -R2-(O-R3) m -S-R1 formula (I) In formula (I), the two R1 terms are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups, the two R2 terms are independently substituted or unsubstituted linear alkylene, the two R3 terms are independently substituted or unsubstituted linear alkylene, m is 0 or 1, and n is an integer of 2 or greater.

[0054] Electroplating compositions provided in embodiments of the present application include a leveling agent having a specific structure shown in formula (I). The leveling agent has an ether oxygen chain: (R3-O) m -(R2-O) n -R2-(O-R3) mThe leveling agent has a nitrogen-containing heterocyclic group bonded to two ends of the ether oxygen chain via a sulfur bond. Electroplating compositions containing a leveling agent with a specific structure are used as electroplating metals to fill through-holes in electronic substrates. Because the leveling agent is selectively adsorbed in areas of high current density, the current density distribution on the cathode surface during the electroplating process can be more effectively controlled. Furthermore, the leveling agent exhibits convection dependence, resulting in a high concentration in areas of high convection intensity. Finally, metal deposition in areas corresponding to high current density is effectively suppressed, resulting in a uniform metal plating layer. In this application, the electroplating composition containing a leveling agent with a specific structure can simultaneously fill through-holes with different openings, reducing copper plating thickness and dimple values ​​and improving the uniformity of electroplating across the entire electronic circuit board. This facilitates the production of fine wiring, promotes improved reliability of electronic products, and better meets the demand for the production of high-density interconnect electronic substrates using a low-cost, simple process. Furthermore, the molecular structure of the leveling agent is stable, facilitating the reduction of impurities in the metal plating layer. Additionally, the leveling agent can be prepared using simple ingredients and processes.

[0055] In an embodiment of the present application, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyridine group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group. The substituted or unsubstituted bipyridine may be a substituted or unsubstituted 2,2'-bipyridine or a substituted or unsubstituted terpyridine. Substituted or unsubstituted nitrogen-containing heterocyclic groups are beneficial in the leveling agent to obtain good leveling properties.

[0056] In embodiments of the present application, the substituents in the substituted nitrogen-containing heterocyclic group may include one or more (two or more) of unsubstituted alkyl, haloalkane, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur (=S), mercapto (-SH), hydroxyl (-OH), carboxy (-COOH), amino (-NH), and amido (-CO-NH). The substituents may be located on the nitrogen atom of the nitrogen heterocycle or on a carbon atom of the nitrogen heterocycle. One or more (two or more) substituents may be present, and the multiple substituents may be the same or different groups. The unsubstituted alkyl and haloalkane may be a haloalkane or unsubstituted alkyl having a carbon number ranging from 1 to 10 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms), specifically, for example, methyl, ethyl, propyl, isopropyl, butyl, or tertbutyl, substituted or unsubstituted by halogen. The substituted or unsubstituted aryl may be a substituted or unsubstituted aryl having 6 to 20 carbon atoms (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms), specifically, for example, substituted or unsubstituted phenyl, naphthyl, or biphenyl. The substituent in the substituted aryl may be a halogen atom, alkyl, mercapto, hydroxyl, amino, or the like. The substituted or unsubstituted alkoxy may be a substituted or unsubstituted alkoxy having 1 to 10 carbon atoms (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 carbon atoms), specifically, for example, substituted or unsubstituted methoxy, ethoxy, propoxy, isopropoxy, butoxy, or tertbutoxy. The substituent in the substituted alkoxy may be a halogen atom, hydroxyl, amino, mercapto, or the like.The substituted or unsubstituted aryloxy may be a substituted or unsubstituted aryloxy having 6 to 20 carbon atoms (e.g., 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms), specifically, for example, a substituted or unsubstituted phenoxy. The substituent in the substituted aryloxy may be a halogen atom, alkyl, mercapto, hydroxyl, amino, or the like. The substituted sulfur group (=S) and the carbon atom of the heterocycle of the nitrogen-containing heterocyclic group form a C=S double bond. The aforementioned halogen atom may include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[0057] In some embodiments of the present application, the substituted or unsubstituted nitrogen-containing heterocyclic group is selected from the group consisting of a pyridine group, a 2,2'-bipyridine group, a terpyridine group, a methoxy-substituted 2,2'-bipyridine group, a hydroxyl-substituted 2,2'-bipyridine group, a carboxyl-substituted 2,2'-bipyridine group, a hydroxymethyl-substituted 2,2'-bipyridine group, an amino-substituted pyridine group, a tertbutyl-substituted 2,2'-bipyridine group, a pyrimidine group, an isoquinoline group, an imidazole group, a methyl-substituted imidazole group, an amino-substituted imidazole group, a phenyl-substituted imidazole group, an amido-substituted imidazole group, and the like. The hydroxyl-substituted pyrimidine group includes any one of a substituted imidazole group, a normal butyl-substituted imidazole group, a methyl-substituted imidazole group, a methoxy-substituted benzimidazole group, a benzimidazole group, an amino-substituted benzimidazole group, a hydroxyl-substituted pyrimidine group, a methyl-substituted pyrimidine group, an amino-substituted pyrimidine group, a benzotriazole group, a triazole group, a methyl-substituted triazole group, a phenyl-substituted triazole group, a tetrazole group, a methyl-substituted tetrazole group, a phenyl-substituted tetrazole group, a triazobenzene group, a thiozole group, and a benzothiazole group.

[0058] In some embodiments of the present application, the two R1 terms may be the same substituted or unsubstituted nitrogen-containing heterocyclic group. In some embodiments of the present application, the two R1 terms may be different substituted or unsubstituted nitrogen-containing heterocyclic groups. When the two R1 terms are the same substituted or unsubstituted nitrogen-containing heterocyclic group, the types of raw materials required to prepare the leveling agent can be reduced, and the preparation process of the leveling agent can be more easily controlled.

[0059] In embodiments of the present application, the two R2 terms are independently substituted or unsubstituted linear alkylenes having 2 to 10 carbon atoms (e.g., 2, 3, 4, 5, 6, 7, 8, 9, and 10 carbon atoms). With a suitable number of carbon atoms, the leveling agent can exhibit good water solubility. The two R2 terms may be the same or different substituted or unsubstituted linear alkylenes. In some embodiments of the present application, the two R2 terms may be the same substituted or unsubstituted linear alkylenes. In some embodiments of the present application, the two R2 terms may be different substituted or unsubstituted linear alkylenes. The linear alkylenes may have a linear or branched structure. Specifically, the substituted or unsubstituted linear alkylenes may be substituted or unsubstituted ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, etc. In embodiments of the present application, the substituted linear alkylenes may be hydroxyl-substituted linear alkylenes. In some embodiments, the two R2 terms are the same group. For example, the two R2 terms are both ethyl, propyl, etc. The two R2 terms are the same group to facilitate preparation of the leveling agent.

[0060] In embodiments of the present application, in formula (I), n may be an integer of 1 or greater. In some embodiments, n may be an integer ranging from 1 to 10. In other words, n may be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. The larger the value of n, the longer the ether oxygen molecular chain, which indicates a stronger inhibitory effect on the electroplated metal and better leveling properties of the leveling agent. Within a suitable range of n values, the leveling agent can achieve a balance between leveling performance and dissolution performance.

[0061] In an embodiment of the present application, the two R3 terms are independently substituted or unsubstituted linear alkylenes having 2 to 10 carbon atoms (e.g., 2, 3, 4, 5, 6, 7, 8, 9, and 10 carbon atoms). The two R3 terms may be the same or different substituted or unsubstituted linear alkylenes. The linear alkylenes may have a linear or branched structure. Specifically, the substituted or unsubstituted linear alkylenes may be substituted or unsubstituted ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, etc. In an embodiment of the present application, the substituted linear alkylenes include linear alkylenes substituted with hydroxyl, for example, propylidene substituted with hydroxyl.

[0062] In the present embodiment, in formula (I), m may be 0 or 1. When m is 0, the leveling agent is represented by formula (Ia): R1-S-(R2-O) n -R2-S-R1(Ia). When m is 1, the leveling agent has the structural formula shown in formula (Ib): R1-S-R3-O-(R2-O) n It has the structural formula shown in -R2-O-R3-S-R1(Ib). When m is 0, the preparation process of the leveling agent is simpler.

[0063] In embodiments herein, the concentration of the leveling agent in the electroplating composition may range from 0.01 ppm to 1000 ppm. In some embodiments, the concentration of the leveling agent ranges from 0.1 ppm to 500 ppm. In some embodiments, the concentration of the leveling agent ranges from 0.2 ppm to 100 ppm. In some embodiments, the concentration of the leveling agent ranges from 1 ppm to 50 ppm. Specifically, in some embodiments, the concentration of the leveling agent may be 1 ppm, 2 ppm, 5 ppm, 8 ppm, 10 ppm, 12 ppm, 15 ppm, 18 ppm, 20 ppm, 25 ppm, 30 ppm, 40 ppm, 50 ppm, 60 ppm, 70 ppm, 80 ppm, 90 ppm, or 100 ppm. The concentration of the leveling agent in the electroplating composition can be controlled within a suitable range to achieve a suitable deposition rate, improve simultaneous filling of through-holes with different openings, reduce the thickness of the surface metal layer and the dimple value, and improve the uniformity of electroplating across the entire electronic circuit board, thereby facilitating the production of fine wiring and improving the reliability of electronic products.

[0064] In an embodiment of the present application, the electroplating composition may further include one or more of an accelerator, an inhibitor, and an inorganic additive, which cooperate with each other to better fill through-holes with different openings, thereby reducing the thickness of the surface metal layer and the dimple value.

[0065] In embodiments of the present application, the accelerator includes, but is not limited to, one or more of sodium 3-mercapto-1-propanesulfonate (MPS), sodium polyanetholesulfonate (SPS), and sodium N,N-dimethyl-dithioformamidopropylenesulfonate (DPS). The addition of an accelerator can provide a depolarization effect, promote metal deposition, and refine the grain of the metal layer. In embodiments of the present application, the accelerator concentration in the electroplating composition can range from 0.01 ppm to 500 ppm. In some embodiments, the accelerator concentration in the electroplating composition can range from 0.05 ppm to 100 ppm. In some embodiments, the accelerator concentration in the electroplating composition can range from 0.2 ppm to 50 ppm. In some embodiments, the accelerator concentration in the electroplating composition can range from 0.5 ppm to 20 ppm. In some embodiments, the accelerator concentration in the electroplating composition can range from 1 ppm to 10 ppm.

[0066] In embodiments of the present application, the inhibitor includes, but is not limited to, one or more of polyethylene glycol (PEG), polypropylene glycol (PPG), block copolymer PEO-PPO-PEO (polyethylene oxide-polypropylene oxide-polyethylene oxide), block copolymer PPO-PEO-PPO (polypropylene oxide-polyethylene oxide-polypropylene oxide), random copolymers of ethylene oxide (EO) and propylene oxide (PO), and propylene glycol block polyether. The addition of the inhibitor suppresses the growth rate of the surface metal and promotes the formation of a thin surface metal layer after electroplating is completed. In embodiments of this application, the concentration of the inhibitor in the electroplating composition may range from 1 ppm to 2000 ppm. In some embodiments, the concentration of the inhibitor in the electroplating composition may range from 10 ppm to 1000 ppm. In some embodiments, the concentration of the inhibitor in the electroplating composition is in the range of 20 ppm to 500 ppm. In some embodiments, the concentration of the inhibitor in the electroplating composition ranges from 50 ppm to 300 ppm, hi some embodiments, the concentration of the inhibitor in the electroplating composition ranges from 100 ppm to 200 ppm.

[0067] In embodiments of the present application, the inorganic additive comprises chloride anions, and the concentration of the chloride anions in the electroplating composition ranges from 0.1 ppm to 100 ppm. In some embodiments, the concentration of the chloride anions in the electroplating composition may range from 0.1 ppm, 1 ppm, 5 ppm, 10 ppm, 20 ppm, 30 ppm, 40 ppm, 50 ppm, 60 ppm, 70 ppm, 80 ppm, 90 ppm, or 100 ppm. The addition of chloride ions densifies and refines the plated crystals.

[0068] In the present embodiment, the metal ion source includes any one of a copper ion source, a nickel ion source, a tin ion source, a cobalt ion source, a ruthenium ion source, and a silver ion source. When a metal layer is pre-deposited, it is understood that the metal ion source in the electroplating composition includes a metal ion source corresponding to the metal element of the pre-deposited metal layer. For example, when a metallic copper layer is pre-deposited, the metal ion source includes a copper ion source.

[0069] In an embodiment of the present application, the copper ion source includes one or more of copper sulfate pentahydrate and copper methanesulfonate. Electroplating is performed using an acid system of the copper ion source, which provides high current efficiency, an environmentally friendly solution, and, due to the cooperation of various additives, can successfully fill blind via holes. In an embodiment of the present application, the concentration of the copper ion source in the electroplating composition ranges from 1 g / L to 120 g / L of copper ions. In some embodiments, the concentration of the copper ion source in the electroplating composition may be, for example, 1 g / L, 10 g / L, 20 g / L, 30 g / L, 40 g / L, 50 g / L, 60 g / L, 70 g / L, 80 g / L, 90 g / L, 100 g / L, 110 g / L, or 120 g / L per copper ion. The concentration of the copper ion source is controlled within a suitable range to balance the deposition rate, brightness, and flatness of the resulting copper plating layer.

[0070] In embodiments of the present application, the at least one acid includes one or more of sulfuric acid and methanesulfonic acid. In embodiments of the present application, the concentration of the at least one acid in the electroplating composition ranges from 1 g / L to 300 g / L. In some embodiments, the concentration of the at least one acid in the electroplating composition may be, for example, 1 g / L, 10 g / L, 20 g / L, 30 g / L, 40 g / L, 50 g / L, 55 g / L, 60 g / L, 70 g / L, 80 g / L, 100 g / L, 120 g / L, 150 g / L, 180 g / L, 200 g / L, 220 g / L, 250 g / L, or 300 g / L. A suitable acid system and suitable acid concentration facilitate obtaining a suitable electroplating rate.

[0071] In one embodiment of the present application, there is further provided a leveling agent having the general structural formula shown in formula (II): R1-S-(R3-O) m -(R2-O) n -R2-(O-R3) m -S-R1 formula (II) In formula (II), the two R1 terms are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups, the two R2 terms are independently substituted or unsubstituted linear alkylene, the two R3 terms are independently substituted or unsubstituted linear alkylene, m is 0 or 1, and n is an integer of 2 or greater.

[0072] When m=0, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

[0073] When m=1, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

[0074] Substituents in substituted nitrogen-containing heterocyclic groups include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

[0075] In formula (II), the selection of various substituted or unsubstituted nitrogen-containing heterocyclic groups contained in the two R1 terms refers to the selection range of the two R1 terms in the leveling agent having the general structural formula shown in the above formula (I). The selection of the two R2 terms and the two R3 terms refers to the selection range of the two R2 terms and the two R3 terms in the leveling agent having the general formula shown in the above formula (I). Details will not be described again here.

[0076] The leveling agent provided in the embodiments of the present application has an ether oxygen chain: (R3-O) m -(R2-O) n -R2-(O-R3) mand nitrogen-containing heterocyclic groups attached to both ends of the ether oxygen chain via sulfur bonds. A leveling agent having a specific structure is prepared in an electroplating solution and used as an electroplating metal to fill through-holes in electronic substrates. The leveling agent is selectively adsorbed in areas of high current density, thereby better controlling the current density distribution on the cathode surface during the electroplating process. Furthermore, the leveling agent is convection-dependent, exhibiting a high concentration in areas of high convection intensity. Finally, metal deposition in areas corresponding to high current density is effectively suppressed, resulting in a uniform metal plating layer. The electroplating solution containing the leveling agent having a specific structure described herein enables simultaneous filling of through-holes with different openings, reduces copper plating thickness and dimple values, and improves the uniformity of electroplating across electronic circuit boards. This facilitates the production of fine wiring, promotes improved reliability of electronic products, and better meets the manufacturing requirements for high-density interconnect electronic substrates using a low-cost, simple process. Furthermore, the molecular structure of the leveling agent provided in the embodiment of the present application is stable, which facilitates reducing the amount of impurities in the metal plating layer.The leveling agent provided in the embodiment of the present application can be prepared using simple raw materials and processes.

[0077] Accordingly, one embodiment of the present application further provides a method for preparing a leveling agent, the method comprising: Compound A:OH-(R2-O) n After substituting -R2-OH with a p-toluenesulfonyl group or an epoxy group, compound A is reacted with a mercapto or a nitrogen-containing heterocyclic compound containing a carbon-sulfur double bond to obtain a leveling agent represented by formula (II), where in compound A, two R2 are independently substituted or unsubstituted linear alkylene, and n is an integer of 1 or greater.

[0078] It can be understood that the selection of the chemical group of R2 and the value of n in compound A are consistent with the selection of the chemical group of R2 and the value of n in the molecular structure of the leveling agent shown in formula (II). In other words, the selection of compound A determines the partial molecular structure of the leveling agent. The selection of the chemical group of R2 and the value of n in compound A refer to the selection of the chemical group of R2 and the value of n in the molecular structure of the leveling agent shown in formula (I). Details will not be described again here.

[0079] In an embodiment of the present application, for example, R2 is isopropyl, n is 3, and compound A is tripropylene glycol.

[0080] In an embodiment of the present application, for example, R2 is ethyl, n is 3, and compound A is triethylene glycol (HO-CH2-CH2-O-CH2-CH2-O-CH2-CH2-O-CH2-CH2-OH). For example, in a method for preparing a leveling agent by using triethylene glycol as a raw material, triethylene glycol is first reacted with toluenesulfonyl chloride and then reacted with 1,5-mercapto-1-methyltetrazole to obtain a leveling agent.

[0081] In an embodiment of the present application, the temperature of the first reaction may range from 50° C. to 90° C., and the time may range from 10 hours to 36 hours. The temperature of the second reaction may range from 50° C. to 90° C., and the time may range from 10 hours to 36 hours.

[0082] In one embodiment of the present application, there is further provided an electroplating composition. The electroplating composition includes a leveling agent having the general structural formula shown in Formula (II) in this embodiment of the present application. The concentration, other components, and content of the leveling agent in the electroplating composition are consistent with those in the aforementioned electroplating compositions. Details will not be described again here.

[0083] One embodiment of the present application further provides for the application of the leveling agent and / or electroplating composition in a metal electroplating process, wherein the electroplated metal may include any one of electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, and electroplated silver and silver alloys.

[0084] In embodiments of the present application, the electroplated metal includes electroplated metal in a printed circuit board preparation process, electroplated metal in an integrated circuit metal interconnect process, or electroplated metal in an electronic packaging process. In particular, the electroplated metal may be electroplated metal in processes such as through-silicon via filling, substrate redistribution, under-bump metallization, and through-hole filling.

[0085] In embodiments of the present application, the electroplated metal includes a superfill metal filled into through-holes of an electronic substrate by electroplating. The electronic substrate may be a common substrate, a printed circuit board, a package substrate, etc. The through-holes may include plated through-holes, blind via holes, and buried via holes. The superfill metal filling may be filled with electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, or electroplated silver and silver alloys.

[0086] The leveling agent and electroplating composition provided in the embodiments of the present application are used to perform metal electroplating to fill through-holes in electronic circuit boards, thereby simultaneously filling through-holes with different openings, reducing the thickness and dimple value of the surface metal layer, and improving the uniformity of electroplating across the entire electronic circuit board. This facilitates the production of fine wiring, helps improve the reliability of electronic products, and better meets the manufacturing requirements of high-density interconnect electronic boards by using a low-cost, simple process.

[0087] In one embodiment of the present application, there is further provided a metal electroplating method including the following steps: contacting a substrate to be electroplated with the electroplating composition provided in an embodiment of the present application, and applying a current to the substrate to be electroplated for electroplating, thereby forming a metal layer on the substrate to be electroplated.

[0088] Specifically, a substrate to be electroplated is immersed in an electroplating composition as a cathode, and the electroplating composition, i.e., the electroplating solution, is used as an electrolyte, forming a conductive loop together with a soluble or insoluble anode, and metal deposition is carried out on the substrate to be electroplated.

[0089] In an embodiment of the present application, a through hole is provided in a substrate to be electroplated, and the metal layer includes an inner hole filling layer that fills the through hole and a surface deposition layer that is deposited around the through hole. The through hole may include one or more of a plated through hole, a blind via hole, and a buried via hole.

[0090] In the present embodiment, the diameter of the through-hole may be in the range of 10 μm to 200 μm, and the depth may be in the range of 20 μm to 200 μm. Specifically, the diameter of the through-hole may be, for example, 10 μm, 20 μm, 30 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm. The through-hole depth may be, for example, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm. The substrate to be electroplated may have through-holes of different diameters and depths.

[0091] In embodiments of the present application, the electroplating process conditions are as follows: the electroplating temperature is in the range of 10° C. to 40° C., the current density is in the range of 0.5 ASD to 5 ASD, and the electroplating time is in the range of 30 minutes to 300 minutes. In some embodiments, the electroplating temperature is 10° C., 20° C., 25° C., 30° C., or 40° C., the current density is 0.5 ASD, 1 ASD, 1.5 ASD, 2 ASD, 2.5 ASD, 3 ASD, 4 ASD, or 5 ASD, and the electroplating time is 30 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes, 180 minutes, 200 minutes, 250 minutes, or 300 minutes.

[0092] Typically, prior to electroplating, a metallization process is performed on the walls of the through-holes, e.g., a metal layer is chemically plated onto the walls of the through-holes to act as a metal seed layer, e.g., a copper seed layer is chemically plated onto the walls of the through-holes.

[0093] In the present embodiment, after the metal layer is formed by electroplating, the metal layer may be smoothed using a process such as chemical mechanical planarization, or the surface deposition layer may be removed using a planarization process. Since the surface deposition layer can be formed on the electroplating composition of the present application with a smooth surface and a thin thickness, the difficulty of the subsequent planarization process can be reduced.

[0094] See Figure 4. In one embodiment of the present application, an electronic substrate 100 is provided, further comprising a substrate layer 101 and a metal layer 102 disposed on the substrate layer. The metal layer 102 is formed by electroplating an electroplating composition in an embodiment of the present application or by using a metal electroplating method in an embodiment of the present application.

[0095] In the present embodiment, the metal layer 102 includes any one of a copper or copper alloy layer, a nickel or nickel alloy layer, a tin or tin alloy layer, a cobalt or cobalt alloy layer, a ruthenium or ruthenium alloy layer, and a silver or silver alloy layer.

[0096] In the embodiment of the present application, a through hole 10 is provided in a substrate layer 101, and a metal layer 102 includes an inner hole filling layer 1021 that fills the through hole 10 and a surface deposition layer 1022 that is deposited around the through hole 10.

[0097] In the present embodiment, a chemically plated metal seed layer 103, for example a copper seed layer formed by performing a metallization process on the through hole 10, is further included between the substrate layer 101 and the metal layer 102.

[0098] In the present embodiment, the diameter of the through hole 10 may be in the range of 10 μm to 200 μm, and the depth may be in the range of 20 μm to 200 μm. In the present embodiment, the diameter of the through hole 10 may be in the range of 10 μm to 200 μm, and the depth may be in the range of 20 μm to 200 μm. Specifically, the diameter of the through hole 10 may be, for example, 10 μm, 20 μm, 30 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm. The depth of the through holes 10 may be, for example, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm. The substrate layer 101 may be provided with multiple through holes 10, and the multiple through holes 10 may have different diameters and depths or the same diameter and depth.

[0099] In embodiments of the present application, the leveling agent may achieve a low dimple value while maintaining a low thickness of the surface deposition layer. In some embodiments, the leveling agent may be applied such that the thickness of the surface deposition layer 1022 is less than 18 μm and the absolute value of the dimple value of the pore filling layer 1021 is less than 5 μm. In some embodiments, the thickness of the surface deposition layer 1022 is less than 17 μm. In some embodiments, the thickness of the surface deposition layer 1022 is less than 16 μm. In some embodiments, the thickness of the surface deposition layer 1022 is less than 15 μm. In some embodiments, the absolute value of the dimple value of the pore filling layer 1021 is less than 5 μm. In some embodiments, the absolute value of the dimple value of the pore filling layer 1021 is 4 μm or less. In some embodiments, the absolute value of the dimple value of the pore filling layer 1021 is 3 μm or less.

[0100] It can be appreciated that during practical semiconductor applications, a process such as chemical mechanical planarization may be used to smooth the metal layer 102, or a planarization process may be used to remove the surface deposition layer 1022.

[0101] In one embodiment of the present application, an electronic device is further provided, which uses the electronic board 100 according to the embodiment of the present application.

[0102] Hereinafter, the embodiments of the present application will be further described using several embodiments.

[0103] Example 1 Triethylene glycol, triethylamine, N'N-dimethylaminopyridine, and dichloromethane are added sequentially to a round-bottom flask and stirred for 5 minutes. Toluenesulfonyl chloride is then added and reacted at a temperature of 50 to 90°C to obtain an intermediate. The intermediate, 5-mercapto-1-methyltetrazole, and acetonitrile are stirred and reacted at a temperature of 50 to 90°C. The solvent is then removed using a rotary evaporator, and the mixture is purified using a column chromatography to obtain Leveling Agent 1. Figure 5 shows the hydrogen nuclear magnetic resonance spectrum of Leveling Agent 1 prepared in Example 1 of the present application.

[0104] The copper electroplating solution comprises the following ingredients by weight: Copper sulfate pentahydrate: 220 g / L (units of copper sulfate pentahydrate); Sulfuric acid: 55g / L; Chloride ions: 60 ppm; Leveling agent 1:10 ppm; Accelerator: 1 ppm; Inhibitor: 100 ppm.

[0105] The blind via holes were filled by electroplating using the copper electroplating solution of Example 1. The electroplating temperature was room temperature, the current density was 1.5 ASD, and the electroplating time was 90 minutes.

[0106] Example 2 Triethylene glycol, epichlorohydrin, sodium hydroxide, tetrabutylammonium fluoride, and water are sequentially added to a round-bottom flask and mixed to react with each other to obtain an intermediate. The resulting intermediate, 4-mercaptopyridine, and isopropyl alcohol are sequentially added to a round-bottom flask equipped with a magnetic stirrer. The mixture is heated to return the vapor, and then purified using column chromatography to obtain leveling agent 2. Figure 6 shows the hydrogen nuclear magnetic resonance spectrum of leveling agent 1 prepared in Example 1 of the present application. Figure 7 shows the carbon nuclear magnetic resonance spectrum of leveling agent 1 prepared in Example 1 of the present application.

[0107] The copper electroplating solution comprises the following ingredients by weight: Copper sulfate pentahydrate: 220g / L (copper sulfate pentahydrate unit); Sulfuric acid: 55g / L; Chloride ions: 60 ppm; Leveling agent 2: 10 ppm; Accelerator: 1 ppm; Inhibitor: 100 ppm.

[0108] The blind via holes were filled by electroplating using the copper electroplating solution of Example 2. Here, the electroplating temperature was room temperature, the current density was 1.5 ASD, and the electroplating time was 60 minutes.

[0109] Comparative Example 1 The copper electroplating solution comprises the following ingredients by weight: Copper sulfate pentahydrate: 220g / L (copper sulfate pentahydrate unit); sulfate 55g / L; Chloride ions: 60 ppm; Accelerator: 1 ppm; Inhibitor: 100 ppm.

[0110] The blind via holes were filled by electroplating using the copper electroplating solution of Comparative Example 1. Here, the electroplating temperature was room temperature, the current density was 1.5 ASD, and the electroplating time was 60 minutes.

[0111] Comparative Example 2 The copper electroplating solution comprises the following ingredients by weight: Copper sulfate pentahydrate: 220g / L (copper sulfate pentahydrate unit); sulfate 55g / L; Chloride ions: 60 ppm; Leveling agent 3: 10 ppm; Accelerator: 1 ppm; Inhibitor: 100 ppm.

[0112] Leveling agent 3 is an N-heterocyclic leveling agent commonly used in the prior art, and has a different structure from the leveling agent used in the present embodiment. Using the copper electroplating solution of Comparative Example 2, blind via holes were filled by electroplating. The electroplating temperature was room temperature, the current density was 1.5 ASD, and the electroplating time was 90 minutes.

[0113] Comparative Example 3 The copper electroplating solution comprises the following ingredients by weight: Copper sulfate pentahydrate: 220g / L (copper sulfate pentahydrate unit); sulfate 55g / L; Chloride ions: 60 ppm; Leveling agent 4: 10 ppm; Accelerator: 1 ppm; Inhibitor: 100 ppm.

[0114] Leveling agent 4 is another N-heterocyclic leveling agent commonly used in the prior art, and has a different structure from the leveling agent used in the present embodiment. Using the copper electroplating solution of Comparative Example 3, blind via holes were filled by electroplating. The electroplating temperature was room temperature, the current density was 1.5 ASD, and the electroplating time was 60 minutes.

[0115] Figure 8 shows the linear sweep voltammetry curves of leveling agents 1, 2, and 3. It can be seen from Figure 8 that in the region where the sedimentation potential is -0.6 V vs. SSE (mercury / mercury sulfate electrode), the polarization ability of leveling agents 1 and 2 is clearly stronger than that of leveling agent 3. Figure 9 shows the cyclic voltammetry curves of leveling agents 1, 2, and 3. It can be seen from Figure 9 that only leveling agents 1 and 2 have hysteresis loops, and that leveling agents 1 and 2 have stronger filling ability.

[0116] 10A, 10B, 10C, and 10D show the results of electroplating blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm, respectively, using the copper electroplating solution of Example 1. FIG. 10A shows the results of electroplating a blind via hole having an 80 μm opening. FIG. 10B shows the results of electroplating a blind via hole having an opening of 100 μm. FIG. 10C shows the results of electroplating a blind via hole having an opening of 125 μm. FIG. 10D shows the results of electroplating a blind via hole having an opening of 150 μm. In FIGS. 10A, 10B, and 10C, the thickness of the surface copper layer is 22 μm, and the dimple value is 0. In FIG. 10D, the thickness of the surface copper layer is 23 μm, and the dimple value is 8 μm.

[0117] 11A, 11B, 11C, and 11D show the results of electroplating blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm, respectively, using the copper electroplating solution of Example 2. FIG. 11A shows the results of electroplating a blind via hole having an 80 μm opening. FIG. 11B shows the results of electroplating a blind via hole having an opening of 100 μm. FIG. 11C shows the results of electroplating a blind via hole having an opening of 125 μm. FIG. 11D shows the results of electroplating a blind via hole having an opening of 150 μm. In FIGS. 11A, 11B, 11C, and 11D, the thickness of the surface copper layer is 17 μm, and the dimple values ​​are 4 μm, 4 μm, 9 μm, and 4 μm, respectively. 12A, 12B, 12C, and 12D show the results of electroplating blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm, respectively, using the copper electroplating solution of Comparative Example 1. In FIGS. 12A, 12B, 12C, and 12D, the thickness of the surface copper layer is 19 μm, and the dimple values ​​are 95 μm, 95 μm, 104 μm, and 84 μm, respectively. 13A, 13B, 13C, and 13D show the results of electroplating blind via holes having openings of 80 μm, 100 μm, 125 μm, and 150 μm, respectively, using the copper electroplating solution of Comparative Example 2. In Figures 13A, 13B, 13C, and 13D, the thickness of the surface copper layer is 22 μm, and the dimple values ​​are 0 μm, 2 μm, 6 μm, and 50 μm, respectively. Figures 14A, 14B, 14C, and 14D show the results of electroplating blind via holes with openings of 80 μm, 100 μm, 125 μm, and 150 μm, respectively, using the copper electroplating solution of Comparative Example 3. In Figures 14A, 14B, 14C, and 14D, the thickness of the surface copper layer is 19 μm, 19 μm, 19 μm, and 20 μm, respectively, and the dimple values ​​are 9 μm, 49 μm, 91 μm, and 93 μm, respectively.

[0118] The electroplating results for Examples 1, 2, and Comparative Examples 1 to 3 show that the addition of leveling agents significantly reduces the dimple value of blind via hole filling in Examples 1 and 2 compared to Comparative Example 1, which did not contain a leveling agent. The dimple value is less than 10 μm. Furthermore, in the present embodiment, using Leveling Agent 1 and Leveling Agent 2 for filling times of 60 and 90 minutes, blind via holes with openings ranging from 80 μm to 150 μm are simultaneously and completely filled, while the copper plating thickness is reduced. However, when using a general leveling agent in Comparative Examples 2 and 3, it is difficult to simultaneously fill small 80 μm holes and large 150 μm holes while maintaining a low dimple value.

[0119] It should be understood that the terms "first," "second," and various numerals used herein are merely for ease of explanation and distinction, and are not intended to limit the scope of the present application.

[0120] In this application, "and / or" represents a correlation between related entities and indicates that three cases may exist. For example, A and / or B may represent three cases: when only A exists, when both A and B exist, and when only B exists. Here, A and B may be singular or plural. The character " / " usually indicates an "or" relationship between related entities.

[0121] As used herein, "at least one" means one or more, and "plurality" means two or more. References to at least one of the following items (elements) or similar expressions refer to any combination of those items, including any combination of singular items (elements) or plural items (elements). For example, "at least one of a, b, or c" or "at least one of a, b, and c" may refer to a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c may be singular or plural.

[0122] The above description is merely a specific description of the present application, and the scope of protection of the present application is not limited thereto. Any modifications or substitutions that can be easily understood by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

Claims

1. 1. A composition comprising: A metal ion source and a leveling agent represented by formula (I): R 1 -S-(R 3 -O) m -(R 2 -O) n -R 2 -(O-R 3 ) m -S-R 1 Formula (I) In formula (I), The Two R's 1 are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups; The Two R's 2 The terms are independently substituted or unsubstituted linear alkylenes, The Two R's 3 The terms are independently substituted or unsubstituted linear alkylenes, A composition wherein m is 0 or 1 and n is an integer of 2 or greater.

2. 2. The composition of claim 1, wherein the substituted or unsubstituted nitrogen-containing heterocyclic group comprises any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyridine group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group.

3. 3. The composition of claim 1 or 2, wherein the substituents in the substituted nitrogen-containing heterocyclic group include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted aryl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

4. The two R 2 are independently substituted or unsubstituted linear alkylenes having from 2 to 10 carbon atoms; The two R 3 4. The composition of claim 1, wherein each term is independently a substituted or unsubstituted linear alkylene having from 2 to 10 carbon atoms.

5. 5. The composition of claim 1, wherein the substituted linear alkylene comprises a linear alkylene substituted with hydroxyl.

6. 6. The composition according to claim 1, wherein the concentration of the leveling agent represented by formula (I) in the composition ranges from 0.01 ppm to 1000 ppm.

7. 7. The composition of claim 1, further comprising at least one acid, wherein the at least one acid comprises one or more of sulfuric acid and methanesulfonic acid.

8. 8. The composition of claim 7, wherein the concentration of the at least one acid in the composition ranges from 1 g / L to 300 g / L.

9. 9. The composition of claim 1, further comprising one or more of an accelerator, an inhibitor, and an inorganic additive.

10. the accelerator comprises one or more of sodium 3-mercapto-1-propanesulfonate, sodium polyanetholesulfonate, and sodium N,N-dimethyl-dithioformamidopropylenesulfonate; 10. The composition of claim 9, wherein the concentration of the accelerator in the composition ranges from 0.01 ppm to 500 ppm.

11. the inhibitor comprises one or more of polyethylene glycol, polypropylene glycol, block copolymer PEO-PPO-PEO, block copolymer PPO-PEO-PPO, random copolymer of EO and PO, and propylene glycol block polyether; 10. The composition of claim 9, wherein the concentration of the inhibitor in the composition ranges from 1 ppm to 2000 ppm.

12. the inorganic additive comprises a chloride anion; 10. The composition of claim 9, wherein the concentration of chloride anions in the composition ranges from 0.1 ppm to 100 ppm.

13. 13. The composition of claim 1, wherein the metal ion source comprises any one of a copper ion source, a nickel ion source, a tin ion source, a cobalt ion source, a ruthenium ion source, and a silver ion source.

14. 14. The composition of claim 13, wherein the copper ion source comprises one or more of copper sulfate pentahydrate and copper methanesulfonate, and the concentration of the copper ion source in the composition ranges from 1 g / L to 120 g / L of copper ions.

15. 15. The application of the composition according to any one of claims 1 to 14 to electroplating metal.

16. 16. The application of claim 15, wherein the electroplated metal comprises any one of electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, and electroplated silver and silver alloys.

17. 17. The application of claim 15 or 16, wherein the electroplated metal comprises metal electroplated into through-holes of an electronic substrate to effect metal filling.

18. Application of the compound represented by formula (I) to electroplating metals: R 1 -S-(R 3 -O) m -(R 2 -O) n -R 2 -(O-R 3 ) m -S-R 1 Formula (I) Here, in formula (I), The Two R's 1 are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups; The Two R's 2 The terms are independently substituted or unsubstituted linear alkylenes, The Two R's 3 The terms are independently substituted or unsubstituted linear alkylenes, m is 0 or 1, and n is an integer of 2 or more.

19. A leveling agent, having the general structural formula shown in formula (II): R 1 -S- (R 3 -O) m - (R 2 -O) n -R 2 - (O-R 3 ) m -S-R 1 Formula (II) wherein in formula (II): The Two R's 1 are independently selected from substituted or unsubstituted nitrogen-containing heterocyclic groups; The Two R's 2 are independently substituted or unsubstituted linear alkylene; The Two R's 3 are independently substituted or unsubstituted linear alkylene; m is 0 or 1, and n is an integer of 2 or greater; When m=0, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group; When m=1, the substituted or unsubstituted nitrogen-containing heterocyclic group includes any one of a substituted or unsubstituted pyrrole group, a substituted or unsubstituted imidazole group, a substituted or unsubstituted pyrimidine group, a substituted or unsubstituted triazole group, a substituted or unsubstituted tetrazole group, a substituted or unsubstituted thiozole group, a substituted or unsubstituted benzopyrrole group, a substituted or unsubstituted benzimidazole group, a substituted or unsubstituted benzopyridine group, a substituted or unsubstituted benzopyrimidine group, a substituted or unsubstituted benzotriazole group, a substituted or unsubstituted benzothiazole group, a substituted or unsubstituted bipyridine group, and a substituted or unsubstituted triazobenzene group; A leveling agent, wherein the substituents in the substituted nitrogen-containing heterocyclic group include one or more of unsubstituted alkyl, haloalkane, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, sulfur, mercapto, hydroxyl, carboxyl, amino, and amido.

20. The two R 2 are independently substituted or unsubstituted linear alkylenes having from 2 to 10 carbon atoms; The two R 3 20. The leveling agent according to claim 19, wherein each term is independently a substituted or unsubstituted chain alkylene having 2 to 10 carbon atoms.

21. 21. The leveling agent according to claim 19 or 20, wherein the substituted linear alkylene comprises a linear alkylene substituted with hydroxyl.

22. 22. A method for preparing the leveling agent according to any one of claims 19 to 21, comprising: Compound A: OH-(R 2 -O) n -R 2 replacing the —OH with a p-toluenesulfonyl group or an epoxy group; Next, reacting the compound A with a mercapto or nitrogen-containing heterocyclic compound containing a carbon-sulfur double bond to obtain the leveling agent; and In the compound A, two R 2 The term "a" is independently a substituted or unsubstituted linear alkylene, and n is an integer of 2 or more.

23. A composition comprising the leveling agent according to any one of claims 19 to 21.

24. 24. The application of a leveling agent according to any one of claims 19 to 22 or a composition according to claim 23 to electroplated metal.

25. 25. The application of claim 24, wherein the electroplated metal comprises any one of electroplated copper and copper alloys, electroplated nickel and nickel alloys, electroplated tin and tin alloys, electroplated cobalt and cobalt alloys, electroplated ruthenium and ruthenium alloys, and electroplated silver and silver alloys.

26. 26. The application of claim 24 or 25, wherein the electroplated metal comprises metal electroplated into through-holes of an electronic substrate to effect metal filling.

27. 1. A method of metal electroplating comprising: contacting a substrate to be electroplated with the composition of any one of claims 1 to 14 or the composition of claim 23; applying a current to a substrate to be electroplated for electroplating to form a metal layer on the substrate to be electroplated; A method comprising:

28. The substrate to be electroplated is provided with a through hole, 28. The method of claim 27, wherein the metal layer comprises an in-hole fill layer that fills the through-hole and a surface deposition layer that is deposited around the through-hole.

29. 29. The method of claim 28, wherein the through-holes have a diameter in the range of 10 μm to 200 μm and a depth in the range of 20 μm to 200 μm.

30. 30. The method of any one of claims 27 to 29, wherein the electroplating process conditions are: electroplating temperature in the range of 10°C to 40°C, current density in the range of 0.5 ASD to 5 ASD, and electroplating time in the range of 30 minutes to 300 minutes.

31. An electronic substrate, a substrate layer and a metal layer disposed on the substrate layer; 31. An electronic substrate, wherein the metal layer is formed by electroplating the composition of claim 1 or the composition of claim 23, or by using the method of metal electroplating of claim 27.

32. An electronic device, 32. An electronic device using the electronic substrate according to claim 31.

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