Compound, preparation method thereof and application of compound in preparation of electroplating additive

Abstract

The invention relates to the technical field of electroplating of printed circuit boards, and particularly discloses a compound, a preparation method of the compound and application of the compound in preparation of an electroplating additive. The compound has a chemical structure as shown in a formula (I), # imgabs0 # formula (I); wherein R1 and R2 are independently selected from one or more groups of methyl, ethyl, methoxyl, phenyl, dimethylaminoethyl, diethylaminoethyl, 4-hydroxyphenyl, sodium methanesulfonate, acetic acid group, ethoxyl, 4-methoxyphenyl, 3-sulfonyl phenyl, 4-carboxylic phenyl, 4-ethoxyl phenyl and 4-chlorphenyl. Researches show that ultrathin surface copper can be prepared by adopting the compound as an electroplating additive; the prepared ultrathin surface copper has a relatively high pore filling rate and a relatively small recess; and the ultra-thin surface copper required by a high-precision circuit can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of printed circuit board electroplating, and specifically relates to a compound, a preparation method thereof, and an application thereof in the preparation of electroplating additives. Background Art

[0002] With the development of the refinement and miniaturization of electronic devices, the substrate wiring of printed circuit boards is designed towards multi-layerization, and the connection holes are designed towards smaller diameters. The number of layers of the circuit board is increasing, and the smaller the connection holes are, the more common it becomes to fill high-density micro-blind holes and arrange fine circuits. This requires the electroplating process to be more efficient and reliable. Electroplated copper filling holes require a thin surface copper thickness and good blind hole filling at the same time.

[0003] In order to obtain filling that meets the requirements of copper-plated blind holes and has a thin surface copper thickness, the organic additives in the electroplated copper bath are particularly crucial.

[0004] The organic additives in the electroplated copper bath are divided into accelerators, leveling agents, and inhibitors. Among them, the leveling agent is the main component for the smoothness and gloss of the copper layer and the filling of blind holes during electroplating. The accelerator and the inhibitor cooperate with the leveling agent to form blind hole filling and inhibit the deposition of surface copper. For traditional conventional blind hole filling electroplating additives, when filling blind holes with a diameter of 120 microns and a dielectric thickness of 75 microns, the depression value is generally about 5-10 microns after filling, and the surface copper thickness reaches more than 15 microns, while ultra-thin hole filling requires a surface copper of 10-12 microns.

[0005] The main traditional acidic copper plating filling accelerators are sodium 3-mercaptopropanesulfonate, sodium disulfanedipropanesulfonate, sodium N,N-dimethylthiopropanesulfonate, etc. The inhibitors are polyethylene glycol, polypropylene glycol, polyethylene glycol-polypropylene glycol block polymers, etc. The leveling agent is mainly the reaction product of an epoxy diluent and an amine. For example, in patents CN103774188, CN103451691, etc., these leveling agents will have a relatively thick surface copper during the blind hole filling process and cannot meet the requirements of the ultra-thin surface copper thickness for high-precision circuits. However, some of the existing electroplating additives, although they can prepare an ultra-thin surface copper, still have defects such as a low hole filling rate and excessive depression. Summary of the Invention

[0006] In order to overcome the technical problems existing in the prior art, the present invention first provides a compound, a preparation method thereof, and an application thereof in the preparation of electroplating additives.

[0007] The above technical problems to be solved by the present invention are realized by adopting the following technical solutions: The present invention first provides a compound having a chemical structure shown in formula (I); Formula (I); Among them, R1 and R2 are independently selected from one or more groups of methyl, ethyl, methoxy, phenyl, dimethylaminoethyl, diethylaminoethyl, 4-hydroxyphenyl, sodium methanesulfonate group, acetate group, hydroxyethyl, 4-methoxyphenyl, 3-sulfophenyl, 4-carboxyphenyl, 4-ethoxyphenyl, and 4-chlorophenyl; A has a chemical structure represented by the general formula (II), (III), or (IV); (II); (III); (IV); Among them, in formula (II), m = 1 - 4; in formula (III), n = 1 - 7; in formula (IV), o = 1 - 3.

[0008] Preferably, R1 and R2 are independently selected from methyl or ethyl.

[0009] Preferably, the compound is specifically selected from the following structures: ; ; ; .

[0010] The present invention also provides a preparation method of the above compound, which comprises the following steps: React a tetrazole compound having the structure shown in formula (VI) with a halide having the structure shown in formula (I), (VIII), (IX), or (X) in a mixed solution of ethanol and water, and the compound is obtained after the reaction ends; Among them, (VI); (VII); (VIII); (IX); Among them, in formulas VI, VII, VIII, and IX, R3 is one group of methyl, ethyl, methoxy, phenyl, dimethylaminoethyl, diethylaminoethyl, 4-hydroxyphenyl, sodium methanesulfonate group, acetate group, hydroxyethyl, 4-methoxyphenyl, 3-sulfophenyl, 4-carboxyphenyl, 4-ethoxyphenyl, 4-chlorophenyl; X is a halogen, Cl, Br; r = 1 - 4; s = 1 - 7; t = 1 - 3.

[0011] Preferably, the molar ratio of the tetrazole compound having the structure shown in formula (VI) to the halide having the structure shown in formula (I), (VIII), (IX) or (X) is 1: (0.48 - 0.52).

[0012] Preferably, for the said reaction, the reaction temperature is 40 - 100 °C and the reaction duration is 2 - 14 h.

[0013] Most preferably, for the said reaction, the reaction temperature is 80 °C and the reaction duration is 4 h.

[0014] Preferably, the volume ratio of ethanol to water is 1 - 4:1; Most preferably, the volume ratio of ethanol to water is 3:1.

[0015] Preferably, the ratio of the total mass of the reactants to the total volume of ethanol and water is 1 kg:5 - 15 L.

[0016] The present invention also provides an application of the above compound in the preparation of an electroplating additive.

[0017] Preferably, the electroplating additive is an ultra-thin via-filling electroplating additive.

[0018] Preferably, the compound is specifically applied in the form of an aqueous solution.

[0019] Beneficial effects: The present invention provides a compound with a brand-new structure; research shows that using the compound of the present invention as an electroplating additive can prepare ultra-thin surface copper; and the prepared ultra-thin surface copper has a high via-filling rate and small depressions; it can meet the requirements of ultra-thin surface copper for high-precision circuits.

[0020] In addition, the present invention also provides a brand-new preparation method for the said compound; this method uses ethanol-water as a solvent and can obtain the said compound by reaction under relatively mild conditions, which is an energy-saving and environmentally friendly preparation method. Specific embodiments

[0021] The following combines specific embodiments to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] Example 1 Put 60 ml of absolute ethanol and 20 ml of deionized water into a three-necked flask. Then add 0.1 mol of 5-mercapto-1-methyltetrazole into the flask and stir. Heat up to 80 °C and stir. Then add 0.05 mol of dichlorodiethyl ether for reaction and continue the reaction for 4 h. Then filter the system to remove a small amount of insoluble substances, collect the filtrate. Then add 150 ml of deionized water to the filtrate, stir for 5 min, and use a separatory funnel to separate the product system. Collect the aqueous part, and after concentration and drying, the described compound is obtained, named T1.

[0023] The chemical name of T1 is 5,5'-((oxybis(ethane-2,1-diyl))bis(thiodiyl))bis(1-methyl-1H-tetrazole), and the structure is as follows: ; The detection data of 1H NMR of T1 are: 1H NMR (400 MH, D2O) δ = 3.91 (m, 6H), 3.83~3.75 (m, 4H), 3.45~3.38 (m, 4H).

[0024] Example 2 Put 60 ml of absolute ethanol and 20 ml of deionized water into a three-necked flask. Then add 0.1 mol of 5-mercapto-1-ethyltetrazole into the flask and stir. Heat up to 80 °C and stir. Then add 0.05 mol of dichlorodiethyl ether for reaction and continue the reaction for 4 h. Then filter the system to remove a small amount of insoluble substances, collect the filtrate. Then add 150 ml of deionized water to the filtrate, stir for 5 min, and use a separatory funnel to separate the product system. Collect the aqueous part, and after concentration and drying, the described compound is obtained, named T2.

[0025] The chemical name of T2 is 5,5'-((oxybis(ethane-2,1-diyl))bis(thiodiyl))bis(1-ethyl-1H-tetrazole), and the structure is as follows: ; The detection data of 1H NMR of T2 are: 1H NMR (400 MH, D2O) δ = 3.99 - 3.95 (m, 4H), 3.82~3.75 (m, 4H), 3.43~3.38 (m, 4H), 1.55 (m, 6H).

[0026] Example 3 60 ml of absolute ethanol and 20 ml of deionized water were charged into a three-necked flask, and then 0.1 mol of 5-mercapto-1-ethyltetrazole was added to the flask and stirred. The temperature was raised to 80 °C and stirred. Then 0.05 mol of 1,2-bis(2-chloroethoxy)ethane was added for reaction, and the reaction continued for 4 h. Then the system was filtered to remove a small amount of insoluble substances, and the filtrate was collected. Then 150 ml of deionized water was added to the filtrate, stirred for 5 min, and the product system was separated using a separating funnel. The aqueous part was collected, concentrated and dried to obtain the described compound, named T3.

[0027] The chemical name of T3 is 1,2-bis(2-((1-methyl-1H-tetrazol-5-yl)thio)ethoxy)ethane, and the structure is as follows: ;

[0028] The detection data of 1H NMR of T3 are as follows: 1H NMR (400 MHz, D2O) δ = 3.92 (m, 6H), 3.82 - 3.75 (m, 4H), 3.55 - 3.49 (m, 4H), 3.43 - 3.38 (m, 4H).

[0029] Example 4 60 ml of absolute ethanol and 20 ml of deionized water were charged into a three-necked flask, and then 0.1 mol of 5-mercapto-1-ethyltetrazole was added to the flask and stirred. The temperature was raised to 80 °C and stirred. Then 0.05 mol of 1,2-bis(2-chloroethoxy)ethane was added for reaction, and the reaction continued for 4 h. Then the system was filtered to remove a small amount of insoluble substances, and the filtrate was collected. Then 150 ml of deionized water was added to the filtrate, stirred for 5 min, and the product system was separated using a separating funnel. The aqueous part was collected, concentrated and dried to obtain the described compound, named T4.

[0030] The chemical name of T4 is 1,2-bis(2-((1-ethyl-1H-tetrazol-5-yl)thio)ethoxy)ethane, and the structure is as follows: ; The detection data of 1H NMR of T4 are as follows: 1H NMR (400 MHz, D2O) δ = 3.99 - 3.95 (m, 4H), 3.82 - 3.75 (m, 4H), 3.55 - 3.49 (m, 4H), 3.43 - 3.38 (m, 4H), 1.55 (m, 6H).

[0031] Test Example 1 PCB was used as an electroplating test piece to perform electroplating operations in electroplating solutions containing different electroplating additives respectively to test the via filling performance of different electroplating additives. Specifically, it includes: 1. Preparation of Electroplated Copper Plating Solution Seven groups of brighteners were set (test numbers were one to seven), among which: numbers one to four were T1 - T4 prepared in Examples 1 - 4 respectively; numbers five to seven were 5 - mercapto - 1 - methyltetrazole, 5 - mercapto - 1 - ethyltetrazole, and 5 - mercapto - 1 - phenyltetrazole respectively.

[0032] The seven groups of electroplating additives were respectively mixed with copper sulfate pentahydrate, sulfuric acid, chloride ions, polyethylene glycol 10000, sodium bis(propylsulfonyl) disulfide, and deionized water to prepare an electroplated copper plating solution. The content of each component in the plating solution: 220 g / L of copper sulfate pentahydrate, 70 g / L of sulfuric acid, 65 ppm of chloride ions, 600 ppm of polyethylene glycol 10000, 2 ppm of sodium bis(propylsulfonyl) disulfide, and the balance was deionized water.

[0033] 2. Electroplating Conditions Electroplated sample: The electroplated board (PCB) had a thickness of 1.6 mm, a blind hole diameter of 100 μm, a surface copper dielectric thickness of 100 μm, a board length of 20 cm, and a width of 5.5 cm. Electroplating parameters were 1.2 ASD × 40 min. The filling rate was calculated as [surface copper dielectric thickness - dimple (absolute value)] / surface copper dielectric thickness 100%, and the test results are shown in Table 1 below.

[0034] Table 1 Filling Hole Effects and Board Surface Effects of Each Test Group

[0035] It can be seen from the test results in Table 1 that for test groups one to four (Examples 1 - 4 as filling hole additives), the surface copper obtained was ultra - thin, with a surface copper thickness of 8 - 9 μm, and its filling rate was greater than 90%, and the dimple was less than 6 μm. While for test groups five to seven (comparative example additives), under the condition of 8 - 9 μm surface copper, their filling rates were all less than 90%, significantly or even greatly less than those of test groups one to four; and the dimple (depression) exceeded 10 μm, much higher than those of test groups one to four; they could not meet the requirements of ultra - thin filling hole electroplating.

[0036] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above - mentioned exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non - restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention.

[0037] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A compound, characterized in that Having a chemical structure shown in formula (I); Formula (I); Wherein, R1 and R2 are independently selected from one or more groups selected from methyl, ethyl, methoxy, phenyl, dimethylaminoethyl, diethylaminoethyl, 4-hydroxyphenyl, sodium methanesulfonate, acetoxy, hydroxyethyl, 4-methoxyphenyl, 3-sulfonatephenyl, 4-carboxylatephenyl, 4-ethoxyphenyl and 4-chlorophenyl; A has a chemical structure represented by general formula (II), (III) or (IV); (II); (III); (IV); Wherein, in formula (II), m=1-4; in formula (III), n=1-7; in formula (IV), o=1-3.

2. The compound according to claim 1, characterized in that R1 and R2 are independently selected from methyl or ethyl.

3. The compound according to claim 1, characterized in that The compound is specifically selected from the following structures: ； ； ； 。 4. The method for preparing the compound according to any one of claims 1 to 3, characterized in that: Include Follow these steps: The tetrazole compound of the structure represented by formula (VI) is reacted with the halide of the structure represented by formula (I), (VIII), (IX) or (X) in a mixed solution of ethanol and water to obtain the compound after the reaction is completed; in, (VI); (VII); (VIII); (IX); Wherein, R3 in formula VI, VII, VIII, IX is methyl, ethyl, methoxy, phenyl, dimethylaminoethyl, diethylaminoethyl, 4-hydroxyphenyl, sodium methanesulfonate, acetate, hydroxyethyl, 4-methoxyphenyl, 3-sulfonate phenyl, 4-carboxylate phenyl, 4-ethoxyphenyl, 4-chlorophenyl, a group; X is a halogen, such as Cl or Br; r=1-4;s=1-7;t=1-3.

5. The method for preparing the compound according to claim 4, characterized in that: The molar ratio of the tetrazole compound of the structure represented by formula (VI) to the halide of the structure represented by formula (I), (VIII), (IX) or (X) is 1:(0.48-0.52).

6. The method for preparing the compound according to claim 4, characterized in that: The reaction temperature is 40-100°C and the reaction time is 2-14h.

7. The method for preparing the compound according to claim 4, characterized in that: The volume ratio of ethanol to water is 1-4:

1.

8. The method for preparing the compound according to claim 4, characterized in that: The total mass of the reactants and the total volume ratio of ethanol and water is 1kg:5-15L.

9. Use of the compound according to any one of claims 1 to 3 in the preparation of an electroplating additive.

10. The use according to claim 9, characterized in that: The electroplating additive is an ultra-thin hole-filling electroplating additive.

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