Polymer, leveler and preparation method thereof, electroplating solution and electroplating method

Abstract

The present application discloses a polymer, a leveler and a preparation method thereof, an electroplating solution and an electroplating method, and belongs to the field of electroplating technology. The polymer includes a plurality of repeating units, and the repeating units include: a binary epoxy compound residue group and a nitrogen-containing group; the binary epoxy compound residue group is a residue formed after the epoxy bond of the binary epoxy compound is ring-opened; the nitrogen-containing group includes: an alkyl group, a dimethylamine group and a nitrogen-containing heterocyclic group connected to both ends of the alkyl group, respectively, and the dimethylamine group is also connected to the binary epoxy compound residue group through a single bond. The polymer is conducive to obtaining a highly coplanar coating at a high current density, and is particularly suitable for use as a leveler in an electroplating solution.

Description

Technical Field

[0001] The present disclosure relates to the field of electroplating technology, and in particular to a polymer, a leveler and a preparation method thereof, an electroplating solution and an electroplating method. Background Art

[0002] In the process of integrated circuit manufacturing, electroplating is usually used to form electrical interconnects. For example, copper is used as an anode and a silicon wafer is used as a cathode. Electroplating is performed in an electroplating solution to deposit copper on the silicon wafer to form copper pillars, which are electrical interconnects. In order to avoid electrical connection failure, the copper pillars on the silicon wafer need to have high coplanarity.

[0003] The related art adds a leveling agent to the electroplating solution to improve the coplanarity of the copper pillars. For example, the chemical structure of the leveling agent is as follows:

[0004]

[0005] Wherein, X is hydrogen, alkyl, monool, diol, triol or polyol group, Y is hydrogen, alkyl, monool, diol, triol or polyol group, and R is a nitrogen-containing atomic group.

[0006] However, the leveler is not suitable for use at high current density. When electroplating is performed using an electroplating solution containing the leveler, the coplanarity of the copper pillars decreases as the current density increases.

[0007] Public Content

[0008] In view of this, the present disclosure provides a polymer, a leveler and a preparation method thereof, an electroplating solution and an electroplating method, which can solve the above technical problems.

[0009] Specifically, the following technical solutions are included:

[0010] In one aspect, a polymer is provided, the polymer comprising a plurality of repeating units, the repeating units comprising: a divalent epoxy compound residue group and a nitrogen-containing group;

[0011] The binary epoxy compound residue group is a residue formed after the ring-opening of the epoxy bond of the binary epoxy compound;

[0012] The nitrogen-containing group includes an alkyl group, a dimethylamino group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamino group is further connected to a divalent epoxy compound residue group through a single bond.

[0013] The polymer provided by the embodiment of the present disclosure combines the binary epoxy compound residue group and the nitrogen-containing group to form a repeating unit. Since the dimethylamine group and the nitrogen-containing heterocyclic group of the nitrogen-containing group both include N atoms, they are all strong positive functional groups with strong positive charge. When the polymer is used in the electroplating process, the N atoms in the nitrogen-containing group can be characteristically adsorbed on the high current density area on the cathode plated piece, competing with the anode ions, so that the polymer inhibits the metal deposition in the high current density area through steric hindrance, and achieves the purpose of slowing down the electroplating speed in the high current density area. Further, on the basis of using the above-mentioned nitrogen-containing group, the nitrogen-containing group is used in combination with the binary epoxy compound residue group, and in the area with greater convection intensity, the polymer has stronger adsorption on the cathode plated piece, and in the area with less convection intensity, the polymer has relatively weak adsorption on the cathode plated piece, and the polymer can adaptively adjust its adsorption on the cathode plated piece according to the size of the current density, providing stronger metal deposition inhibition for the area with greater current density, and providing weaker metal deposition inhibition for the area with less current density.

[0014] The polymer provided in the embodiment of the present disclosure has a positive effect on obtaining a highly uniform coating, and is particularly suitable for obtaining a coating with high coplanarity at a high current density, which has a positive significance for improving the coplanarity of the coating while increasing the plating speed at a high current density, making the polymer in the embodiment of the present disclosure particularly suitable as a leveling agent in the electroplating solution.

[0015] In some possible implementations, the number of carbon atoms in the alkyl group is 1-5, for example, 1, 2, 3, 4, 5. The number of carbon atoms in the alkyl group is within the above range, so that the polymer has a suitable molecular weight and the polymer can obtain better adsorption capacity on the cathode plated part.

[0016] In some possible implementations, the nitrogen-containing heterocyclic group is a morpholine group or a pyrrolyl group, both of which are strongly positively charged groups, which are conducive to the adsorption of the polymer in a high current density area.

[0017] In some possible implementations, the chemical formula of the nitrogen-containing group includes:

[0018] or

[0019] Wherein, b is an integer, and 1≤b≤5.

[0020] In some possible implementations, the binary epoxy compound residue group includes: a non-epoxy linking group, and two epoxy residues respectively connected to both ends of the non-epoxy linking group;

[0021] The epoxy residue is a residue formed after the ring-opening of the epoxy bond, and the epoxy residue is connected to the dimethylamine group.

[0022] In some possible implementations, the chemical structural formula of the binary epoxy compound residue group is one of the following chemical structural formulas:

[0023] or

[0024] Among them, a 1 、a 2 、a 3 、a 4 are all integers, and are individually integers from 0 to 8.

[0025] In some possible implementations, the number of repeating units is 3-100, which allows the polymer to have a suitable molecular weight and obtain better adsorption capacity on the cathode plated component.

[0026] In some possible implementations, the chemical structure of the polymer is as follows:

[0027]

[0028] Wherein, 0≤a≤8, 1≤b≤5, 3≤n≤100, and a, b, and n are all integers;

[0029] R is or

[0030] The polymer having the above chemical structure is particularly conducive to obtaining a highly uniform coating, and is suitable for obtaining a coating with high coplanarity at a high current density. That is to say, when the polymer having the above chemical structure is used in the electroplating solution, it can effectively solve the contradiction between the electroplating production efficiency and the coplanarity of the coating, and the electroplating rate can be significantly improved without losing the coplanarity of the coating.

[0031] On the other hand, a method for preparing a polymer is provided, wherein the polymer comprises a plurality of repeating units, wherein the repeating units comprise: a binary epoxy compound residue group and a nitrogen-containing group; the nitrogen-containing group comprises: an alkyl group, a dimethylamine group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamine group is further connected to the binary epoxy compound residue group through a single bond;

[0032] The preparation method of the polymer comprises: polymerizing a binary epoxy compound and a nitrogen-containing compound in a solvent to obtain a polymer;

[0033] Wherein, the residue formed after the ring-opening of the epoxy bond of the binary epoxy compound serves as the binary epoxy compound residue group;

[0034] The nitrogen-containing compound includes an alkyl group, an amine group connected to both ends of the alkyl group, and a nitrogen-containing heterocyclic group. The residue formed after the amine group of the nitrogen-containing compound participates in the polymerization reaction serves as the nitrogen-containing group.

[0035] The two epoxy groups at both ends of the binary epoxy compound and the amine group in the nitrogen-containing compound participate in the polymerization reaction. The epoxy group on the binary epoxy compound can undergo a polymerization reaction with the active hydrogen on the amine group of the nitrogen-containing compound. During the reaction, the epoxy group is ring-opened to generate a hydroxyl group and a methylene group, and the amine group forms a dimethylamine group, which is connected to the methylene group as a nucleophile. That is to say, the epoxy group of the binary epoxy compound forms a hydroxyl group and a methylene group in the binary epoxy compound residue group after the polymerization reaction, and the amine group in the nitrogen-containing compound forms a dimethylamine group in the nitrogen-containing group after the polymerization reaction. The dimethylamine group is connected to the methylene group through a single bond, thereby realizing the connection between the nitrogen-containing group and the binary epoxy compound residue group, and obtaining a polymer having the embodiment shown in the present disclosure.

[0036] In some possible implementations, the number of carbon atoms in the alkyl group is 1 to 5. When the number of carbon atoms in the alkyl group is within the above range, the polymer has a suitable molecular weight, and the polymer can obtain better adsorption capacity on the cathode plated component.

[0037] In some possible implementations, the nitrogen-containing heterocyclic group is a morpholinyl group or a pyrrolyl group.

[0038] In some possible implementations, the chemical structural formula of the nitrogen-containing compound includes:

[0039] or

[0040] Wherein, b is an integer, and 1≤b≤5.

[0041] In some possible implementations, the binary epoxy compound includes: a non-epoxy connecting group, and two epoxy groups respectively connected to both ends of the non-epoxy connecting group.

[0042] In some possible implementations, the chemical structural formula of the binary epoxy compound is one of the following chemical structural formulas:

[0043] or

[0044] Among them, a 1 、a 2 、a 3 、a 4 are all integers, and are individually integers from 0 to 8.

[0045] In some possible implementations, the polymerization reaction temperature is 60° C.-75° C. Within the above reaction temperature range, the polymerization reaction can proceed rapidly and thoroughly with a high reaction rate. In addition, the reaction temperature can be kept stable by using a water bath or an oil bath.

[0046] In some possible implementations, the solvent includes at least one of ethanol, methanol, and water.

[0047] In another aspect, provided is a use of any one of the above polymers in preparing a leveling agent.

[0048] Any of the above-mentioned polymers refers to any of the polymers involved in the aforementioned embodiments of the polymer and the embodiments of the method for preparing the polymer in the present disclosure.

[0049] The polymers provided in the embodiments of the present disclosure can be used to prepare a leveling agent. In some cases, these polymers can be used directly as a leveling agent. The prepared leveling agent is particularly advantageous for obtaining a highly uniform coating, and the prepared leveling agent is suitable for obtaining a coating with high coplanarity at a high current density. In other words, the leveling agent prepared based on the polymer provided in the embodiments of the present disclosure can effectively solve the contradiction between electroplating production efficiency and coating coplanarity. Without losing the coating coplanarity (e.g., copper column coplanarity), the electroplating rate can be significantly improved, for example, to at least greater than 2 μm / min, and further greater than 4 μm / min.

[0050] In another aspect, a leveler is provided, comprising any one of the above-mentioned polymers.

[0051] Any of the above-mentioned polymers refers to any of the polymers involved in the aforementioned embodiments of the polymer and the embodiments of the method for preparing the polymer in the present disclosure.

[0052] In some possible implementations, the chemical structure of the polymer is as follows:

[0053]

[0054] Among them, 2≤a≤4, 2≤b≤3, 5≤n≤40;

[0055] R is or

[0056] On the other hand, a method for preparing a leveler is provided. The method for preparing the leveler is the same as the method for preparing any of the polymers described in the embodiments of the present disclosure. That is, the desired leveler of the embodiments of the present disclosure can be obtained by using the same method as the method for preparing any of the polymers described in the embodiments of the present disclosure.

[0057] According to another aspect of the embodiments of the present disclosure, there is provided an electroplating solution, the electroplating solution comprising any one of the above-mentioned leveling agents.

[0058] Any of the aforementioned types of leveling agents in the embodiments of the present disclosure can be used in the electroplating solution and play a role in obtaining a highly uniform coating. At the same time, a coating with high coplanarity can also be obtained under high current density. The electroplating solution provided by the embodiments of the present disclosure effectively solves the contradiction between electroplating production efficiency and coating coplanarity. The electroplating rate can be significantly improved without losing the coating coplanarity (such as copper column coplanarity). Compared with improving equipment or replacing the electroplating solution system, using the electroplating solution provided by the embodiments of the present disclosure to solve the above technical problems is more convenient, easy and reliable, and is also conducive to the maintenance of the electroplating solution.

[0059] In some possible implementations, the electroplating solution further includes: a metal salt, an acid solution, a water-soluble chloride, an accelerator, and an inhibitor;

[0060] Wherein, the concentration of the metal salt in the electroplating solution is 5g / L-300g / L;

[0061] The concentration of the acid solution in the electroplating solution is 10 g / L-300 g / L;

[0062] The concentration of chloride ions in the water-soluble chloride in the electroplating solution is 1ppm-100ppm;

[0063] The concentration of the leveler in the electroplating solution is 0.01ppm-1000ppm;

[0064] The concentration of the accelerator in the electroplating solution is 0.01ppm-100ppm;

[0065] The concentration of the inhibitor in the plating solution is 1 ppm-2000 ppm.

[0066] In some possible implementations, the metal salt includes at least one of copper sulfate, copper cyanide and copper pyrophosphate;

[0067] The acid solution includes at least one of sulfuric acid, hydrochloric acid and an organic acid;

[0068] The water-soluble chloride includes at least one of hydrochloric acid, sodium chloride, potassium chloride and ammonium chloride.

[0069] In some possible implementations, the accelerator is at least one of sodium polydisulfide propane sulfonate and sodium 3-mercapto-1-propane sulfonate; the above-mentioned types of accelerators are conducive to making the coating distribution dense, improving the throwing power of the electroplating solution, and making the coating smooth and reflective.

[0070] The inhibitor includes at least one of polyethylene glycol, polypropylene glycol, PEO-PPO-PEO block copolymer and PPO-PEO-PPO block copolymer. The above inhibitors are easily adsorbed on the active points of grain growth, increase the electrochemical reaction resistance, and enhance the electrochemical polarization, thereby achieving the effect of refining the grains and inhibiting the growth of the plate surface coating.

[0071] According to another aspect of the embodiments of the present disclosure, a method for electroplating a plated component is provided, the method comprising: using any one of the above-mentioned electroplating solutions.

[0072] The plated part is a cathode plated part, and its material includes but is not limited to: resin, ceramic, metal, silicon chip wafer, etc.

[0073] By using the electroplating solution provided in the embodiment of the present disclosure for electroplating, a highly uniform coating can be obtained. In particular, even under high current density and high plating speed conditions, a highly uniform coating can still be obtained, and a high electroplating efficiency is ensured.

[0074] In some possible implementations, the method includes: performing the electroplating at a current density greater than or equal to 5 ASD.

[0075] In some possible implementations, the method includes: performing the electroplating at a current density greater than or equal to 15 ASD.

[0076] In some examples, the method for electroplating a plated part provided by the embodiments of the present disclosure includes performing electroplating at a plating rate ≥ 2 μm / min.

[0077] It can be seen that the electroplating method provided in the embodiment of the present disclosure is suitable for use under high current density and can obtain a coating with high coplanarity.

[0078] In some examples, the embodiments of the present disclosure use a silicon wafer as a cathode plated object and copper ions as the metal to be plated, and perform electroplating in the above-mentioned electroplating solution, so as to form highly coplanar copper columns on the silicon wafer, and the current density during electroplating is greater than 5ASD, and further, greater than or equal to 15ASD; the plating speed is greater than 2μm / min, and further, the plating speed is greater than 4μm / min. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 A laser confocal microscope image of a copper pillar provided for Test Example 1 of the present disclosure;

[0080] Figure 2 Laser confocal microscope image of the copper pillar provided for Test Example 2 of the present disclosure;

[0081] Figure 3A laser confocal microscope image of a copper pillar provided for Test Example 3 of the present disclosure;

[0082] Figure 4 A laser confocal microscope image of a copper column provided for Comparative Example 1 of the present disclosure;

[0083] Figure 5 This is a laser confocal microscope image of the copper pillar provided for Comparative Example 2 of the present disclosure. DETAILED DESCRIPTION

[0084] In order to make the technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0085] As an important component of semiconductor chips, metal interconnects can interconnect various components in integrated circuits to form the required circuits. Copper pillars are widely used in integrated circuits as a typical metal interconnect. They are used to connect the chip and the substrate in integrated circuits and have excellent electrical properties, thermal properties and reliability. Copper pillars are prepared by electroplating, which includes: using copper as an anode and a silicon wafer as a cathode, electroplating in an electroplating solution, and depositing copper on the silicon wafer to form copper pillars.

[0086] In order to avoid electrical connection failure, higher requirements are placed on the flatness of the copper pillars, that is, the coplanarity of the copper pillars. It is usually required that the non-coplanarity rate used to characterize the coplanarity of the copper pillars is less than 10%, so that the copper pillars have high coplanarity.

[0087] Among them, the non-coplanarity rate, on the one hand, represents the ratio of the height of defects such as protrusions or depressions on the top surface of a single copper pillar to the height of the shoulder of the copper pillar; on the other hand, it represents the difference in copper pillar height on the same cathode plated part (that is, the coplanarity of the copper pillar array), which refers to the (highest value of the copper pillar - the lowest value of the copper pillar) divided by twice the average height of the copper pillar within the wafer body (die) of each chip.

[0088] The related art uses a leveling agent to improve the coplanarity of copper pillars by adding a leveling agent to the electroplating solution. For example, the chemical structure of the leveling agent is shown below:

[0089]

[0090] Wherein, X is hydrogen, alkyl, monool, diol, triol or polyol group, Y is hydrogen, alkyl, monool, diol, triol or polyol group, and R is a nitrogen-containing atomic group.

[0091] Since the current density directly affects the plating speed of the copper column, it further affects the production efficiency of the copper column, wherein the greater the current density, the greater the plating speed. In order to obtain a higher copper column production efficiency, it is expected that the current density during electroplating is greater than 5ASD (ampere / square decimeter). However, the leveling agent provided by the related art is not suitable for use under high current density. When electroplating is performed using an electroplating solution containing the leveling agent, the coplanarity of the copper column deteriorates as the current density increases. It can be seen that it is very necessary to provide a leveling agent suitable for use under high current density.

[0092] According to one aspect of an embodiment of the present disclosure, an embodiment of the present disclosure provides a polymer, wherein the polymer includes a plurality of repeating units, wherein the repeating units include: a binary epoxy compound residue group and a nitrogen-containing group.

[0093] The binary epoxy compound residue group is a residue formed after the ring-opening of the epoxy bond of the binary epoxy compound.

[0094] The nitrogen-containing group includes an alkyl group, a dimethylamino group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamino group is further connected to a divalent epoxy compound residue group through a single bond.

[0095] In the electroplating process, the cathode is usually an irregular plated part, for example, the cathode is a pattern with different interconnected structures. According to the initial current density distribution in the electroplating process, the current density of the close-range area with a smaller geometric distance (i.e., closer) between the cathode and the anode is larger, while the current density of the long-range area with a larger geometric distance (i.e., farther) between the cathode and the anode is relatively small. This current density difference caused by the cathode geometry can cause uneven coating on the cathode plated part. According to the current density distribution rule, this coating unevenness will become more serious with the increase of current density. In the process of microelectronics manufacturing, it has extremely high and almost harsh requirements for the uniformity of the metal interconnection structure, that is, the coating. Therefore, when using electroplating technology to manufacture microelectronics, in order to ensure the uniformity of the coating on the cathode plated part, it is necessary to add additives in the electroplating solution to characteristically accelerate and suppress the coating deposition speed at different sites, so as to achieve a uniform coating effect.

[0096] The polymer provided by the embodiment of the present disclosure combines a binary epoxy compound residue group and a nitrogen-containing group to form a repeating unit. Since the dimethylamine group and the nitrogen-containing heterocyclic group of the nitrogen-containing group both include N atoms, they are both strongly positively charged functional groups with strong positive charge. When the polymer is used in the electroplating process, the N atoms in the nitrogen-containing group can be characteristically adsorbed in the high current density area on the cathode plated piece, competing with the anode ions, so that the polymer inhibits metal deposition (such as copper deposition) in the high current density area through steric hindrance, thereby achieving the purpose of slowing down the electroplating speed in the high current density area. Furthermore, on the basis of using the above-mentioned nitrogen-containing group, the nitrogen-containing group is used in combination with a binary epoxy compound residue group, so that the polymer also has the characteristics of convection dependence and current intensity dependence (wherein convection refers to the flowing electroplating solution, and the greater the flow rate of the electroplating solution, the greater the convection intensity). In this way, in areas with greater convection intensity, the adsorption of the polymer on the cathode plated component is stronger, and in areas with less convection intensity, the adsorption of the polymer on the cathode plated component is relatively weaker. In addition, the polymer can adaptively adjust its adsorption on the cathode plated component according to the current density, providing stronger metal deposition inhibition for areas with greater current density and weaker metal deposition inhibition for areas with less current density.

[0097] It can be seen that the polymer provided in the embodiment of the present disclosure has a positive effect on obtaining a highly uniform coating, and is particularly suitable for obtaining a coating with high coplanarity under high current density, which has a positive significance for improving the coplanarity of the coating while increasing the plating speed under high current density, making the polymer in the embodiment of the present disclosure particularly suitable as a leveling agent in the electroplating solution.

[0098] In some possible implementations, in the nitrogen-containing group, the number of carbon atoms in the alkyl group is 1-5, for example, 1, 2, 3, 4, 5. The number of carbon atoms in the alkyl group is within the above range, so that the polymer has a suitable molecular weight and the polymer can obtain better adsorption capacity on the cathode plated part.

[0099] In some possible implementations, among the nitrogen-containing groups, the nitrogen-containing heterocyclic group is a morpholine group or a pyrrolyl group, both of which are strongly positively charged groups, which are beneficial for the adsorption of the polymer in the high current density area.

[0100] Based on the above, in the embodiments of the present disclosure, the chemical structural formula of the nitrogen-containing group includes one of the following chemical structural formulas:

[0101] or

[0102] Wherein, b is an integer, and 1≤b≤5.

[0103] The binary epoxy compound residue group is a residue group derived from a binary epoxy compound, wherein two epoxy bonds in the binary epoxy compound participate in a polymerization reaction and then undergo ring-opening to form the above-mentioned binary epoxy compound residue group.

[0104] In some possible implementations, the binary epoxy compound residue group includes: a non-epoxy connecting group and two epoxy residues respectively connected to both ends of the non-epoxy connecting group; wherein the epoxy residue is a residue formed after the ring-opening of the epoxy bond, and the epoxy residue is connected to the dimethylamine group.

[0105] The non-epoxy linking group refers to a group that does not contain an epoxy group. The non-epoxy linking group is defined as M, and the chemical structure of the binary epoxy compound residue group is as follows:

[0106]

[0107] The chemical structure of the polymer composed of the binary epoxy compound residue group and the above nitrogen-containing group is as follows:

[0108]

[0109] In some possible implementations, the chemical structural formula of the binary epoxy compound residue group is one of the following chemical structural formulas:

[0110] or

[0111] Among them, a 1 、a 2 、a 3 、a 4 are all integers, and are individually integers of 0-8, for example, they can be 0, 1, 2, 3, 4, 5, 6, 7, 8 respectively.

[0112] In some possible implementations, the number of repeating units in the polymer is 3-100, for example, an integer of 3-90, an integer of 3-80, an integer of 3-70, an integer of 3-60, an integer of 3-50, an integer of 3-40, an integer of 3-30, an integer of 3-20, etc., which makes the polymer have a suitable molecular weight and can obtain better adsorption capacity on the cathode plated part.

[0113] In some possible implementations, the embodiments of the present disclosure provide such a polymer, the chemical structure of the polymer is as follows:

[0114]

[0115] Wherein, 0≤a≤8, 1≤b≤5, 3≤n≤100, and a, b, and n are all integers;

[0116] R is or

[0117] For example, a can be 0, 1, 2, 3, 4, 5, 6, 7, 8; b can be 1, 2, 3, 4, 5; n is an integer from 3 to 100, for example, an integer from 3 to 90, an integer from 3 to 80, an integer from 3 to 70, an integer from 3 to 60, an integer from 3 to 50, an integer from 3 to 40, an integer from 3 to 30, an integer from 3 to 20, etc.

[0118] The polymer with the above chemical formula provided by the embodiment of the present disclosure is particularly conducive to obtaining a highly uniform coating, and is suitable for obtaining a coating with high coplanarity at a high current density. That is to say, when the polymer with the above chemical formula is used in the electroplating solution, it can effectively solve the contradiction between electroplating production efficiency and coating coplanarity. Without losing the coplanarity of the coating (such as the coplanarity of the copper column), the electroplating rate can be significantly improved, for example, to greater than 2μm / min, and further greater than 4μm / min. Compared with improving equipment or replacing the electroplating solution system, using the above polymer provided by the embodiment of the present disclosure to solve the above technical problems is more convenient, easy and reliable, and is also conducive to the maintenance of the electroplating solution.

[0119] In some examples, a is 2, 3 or 4, b is 2 or 3, and n is an integer of 5-40, which makes the above polymer have a more suitable molecular weight and N atom density, so that the polymer can obtain better adsorption ability on the cathode plated part.

[0120] For example, when a is 2, b is 2, and R is The chemical structure of the corresponding polymer is as follows:

[0121]

[0122] For example, when a is 2, b is 3, and R is The chemical structure of the corresponding polymer is as follows:

[0123]

[0124] For example, when a is 2, b is 3, and R is The chemical structure of the corresponding polymer is as follows:

[0125]

[0126] For example, when a is 4, b is 3, and R is The chemical structure of the corresponding polymer is as follows:

[0127]

[0128] According to another aspect of an embodiment of the present disclosure, a method for preparing a polymer is also provided, wherein the polymer includes a plurality of repeating units, wherein the repeating units include: a binary epoxy compound residue group and a nitrogen-containing group; the nitrogen-containing group includes: an alkyl group, a dimethylamine group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamine group is also connected to the binary epoxy compound residue group through a single bond.

[0129] The preparation method of the polymer comprises: making a binary epoxy compound and a nitrogen-containing compound undergo polymerization reaction in a solvent to obtain the polymer.

[0130] The residue formed after the ring-opening of the epoxy bond of the binary epoxy compound serves as the binary epoxy compound residue group in the polymer.

[0131] The nitrogen-containing compound includes an alkyl group, an amine group connected to both ends of the alkyl group, and a nitrogen-containing heterocyclic group. The residue formed after the amine group of the nitrogen-containing compound participates in the polymerization reaction serves as the nitrogen-containing group.

[0132] The preparation method of the polymer provided in the embodiment of the present disclosure is to make a binary epoxy compound and a nitrogen-containing compound undergo a polymerization reaction in a solvent, and the two epoxy groups at both ends of the binary epoxy compound and the amine group in the nitrogen-containing compound participate in the polymerization reaction, and the epoxy group on the binary epoxy compound can undergo a polymerization reaction with the active hydrogen on the amine group of the nitrogen-containing compound. During the reaction, the epoxy group is ring-opened to generate a hydroxyl group and a methylene group, and the amine group forms a dimethylamine group, and the dimethylamine group is connected to the methylene group as a nucleophilic reagent. That is to say, the epoxy group of the binary epoxy compound forms a hydroxyl group and a methylene group in the binary epoxy compound residue group after the polymerization reaction, and the amine group in the nitrogen-containing compound forms a dimethylamine group in the nitrogen-containing group after the polymerization reaction, and the dimethylamine group is connected to the methylene group through a single bond, thereby realizing the connection between the nitrogen-containing group and the binary epoxy compound residue group, and obtaining the polymer shown in the embodiment of the present disclosure.

[0133] It can be seen that the polymer prepared by the above-mentioned preparation method has a repeating unit including: a binary epoxy compound residue group and a nitrogen-containing group; the nitrogen-containing group includes: an alkyl group, a dimethylamine group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamine group is also connected to the binary epoxy compound residue group through a single bond.

[0134] For the nitrogen-containing compound, the alkyl group and the nitrogen-containing heterocyclic group therein do not participate in the polymerization reaction, so that the alkyl group and the nitrogen-containing heterocyclic group in the nitrogen-containing compound are the same as the alkyl group and the nitrogen-containing heterocyclic group in the polymer.

[0135] The molecular weight of the polymer (i.e., the number of repeating units) can be controlled by at least one of the following parameters: the mass of the dicyclic epoxy compound and the nitrogen-containing compound, the reaction time, the reaction temperature, etc. For example, when the reaction time is within 24 hours, if the amount of the dicyclic epoxy compound and the nitrogen-containing compound is sufficient, the longer the reaction time, the greater the number of repeating units. When the reaction time exceeds 24 hours, the number of repeating units can be controlled more by other factors.

[0136] In some possible implementations, in the nitrogen-containing group, the number of carbon atoms in the alkyl group is 1-5, for example, 1, 2, 3, 4, 5. The number of carbon atoms in the alkyl group is within the above range, so that the polymer has a suitable molecular weight and the polymer can obtain better adsorption capacity on the cathode plated part.

[0137] In some possible implementations, among the nitrogen-containing groups, the nitrogen-containing heterocyclic group is a morpholine group or a pyrrolyl group, both of which are strongly positively charged groups, which are beneficial for the adsorption of the polymer in the high current density area.

[0138] In some possible implementations, the chemical structural formula of the nitrogen-containing compound involved in the embodiments of the present disclosure includes:

[0139] or

[0140] Wherein, b is an integer, and 1≤b≤5.

[0141] For example, for the nitrogen-containing compound having a morpholine group, when b is 2, the nitrogen-containing compound is N-(2-aminoethyl)morpholine, and when b is 3, the nitrogen-containing compound is N-(3-aminopropyl)morpholine.

[0142] Regarding the nitrogen-containing compound having a pyrrolyl group, when b is 2, the nitrogen-containing compound is N-(2-aminoethyl)pyrrolidine, and when b is 3, the nitrogen-containing compound is N-(3-aminopropyl)pyrrolidine.

[0143] In some possible implementations, the binary epoxy compound includes: a non-epoxy linking group and two epoxy groups connected to both ends of the non-epoxy linking group, respectively, wherein the non-epoxy linking group does not participate in the polymerization reaction, and only the two epoxy groups participate in the polymerization reaction.

[0144] For example, the chemical structural formula of the binary epoxy compound is one of the following chemical structural formulas:

[0145] or

[0146] Among them, a1 、a 2 、a 3 、a 4 are all integers, and are individually integers from 0 to 8.

[0147] For example, the present disclosure provides a binary epoxy compound particularly suitable for preparing a leveling agent, and its chemical structure is as follows:

[0148]

[0149] When a is 2, the divalent epoxy compound is 1,4-butanediol diglycidyl ether, and when a is 4, the divalent epoxy compound is 1,6-hexanediol diglycidyl ether.

[0150] In some possible implementations, the chemical structure of the polymer is as follows:

[0151]

[0152] Wherein, 0≤a≤8, 1≤b≤5, 3≤n≤100, and a, b, and n are all integers;

[0153] R is or

[0154] For example, a can be 0, 1, 2, 3, 4, 5, 6, 7, 8; b can be 1, 2, 3, 4, 5; and n is an integer from 3 to 100.

[0155] In some examples, when the divalent epoxy compound is 1,4-butanediol diglycidyl ether and the nitrogen-containing compound is N-(3-aminopropyl)morpholine, the chemical structure of the prepared polymer is as follows:

[0156]

[0157] In some examples, when the binary epoxy compound is 1,4-butanediol diglycidyl ether and the nitrogen-containing compound is N-(3-aminopropyl)pyrrolidine, the chemical structure of the prepared polymer is as follows:

[0158]

[0159] In some examples, when the binary epoxy compound is 1,6-hexanediol diglycidyl ether and the nitrogen-containing compound is N-(3-aminopropyl)morpholine, the chemical structure of the prepared polymer is as follows:

[0160]

[0161] In order to make the polymerization reaction proceed fully and thoroughly, the above polymerization reaction can be carried out under stirring conditions. Furthermore, the nitrogen-containing compound can be gradually added to the divalent epoxy compound, which is conducive to sufficient and uniform mixing of the divalent epoxy compound and the nitrogen-containing compound.

[0162] In the embodiment of the present disclosure, the reaction temperature of the polymerization reaction between the binary epoxy compound and the nitrogen-containing compound is 60°C-75°C. For example, this includes but is not limited to: 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, etc.

[0163] In the above reaction temperature range, the polymerization reaction can be carried out rapidly and thoroughly, with a high reaction rate. In addition, the reaction temperature can be kept stable by a water bath or an oil bath.

[0164] The polymerization reaction of the binary epoxy compound and the nitrogen-containing compound is carried out in a solvent. In the embodiment of the present disclosure, the applicable solvent includes at least one of ethanol, methanol and water. For example, the solvent is ethanol.

[0165] After the polymerization reaction is completed, the reaction system needs to be post-treated to remove the solvent therein to obtain a high-purity leveling agent. For example, the post-treatment includes but is not limited to: vacuum distillation, for example, using a rotary evaporator to perform vacuum rotary evaporation to quickly remove the solvent in the reaction system.

[0166] According to another aspect of the embodiments of the present disclosure, there is also provided a use of any one of the polymers mentioned above in the embodiments of the present disclosure in preparing a leveling agent.

[0167] Any of the above-mentioned polymers refers to any of the polymers involved in the aforementioned embodiments of the polymer and the embodiments of the method for preparing the polymer in the present disclosure.

[0168] The polymers provided in the embodiments of the present disclosure can be used to prepare a leveling agent. In some cases, these polymers can be used directly as a leveling agent. The prepared leveling agent is particularly advantageous for obtaining a highly uniform coating, and the prepared leveling agent is suitable for obtaining a coating with high coplanarity at a high current density. In other words, the leveling agent prepared based on the polymer provided in the embodiments of the present disclosure can effectively solve the contradiction between electroplating production efficiency and coating coplanarity. Without losing the coating coplanarity (e.g., copper column coplanarity), the electroplating rate can be significantly improved, for example, to at least greater than 2 μm / min, and further greater than 4 μm / min.

[0169] According to another aspect of the embodiments of the present disclosure, a leveler is provided. The leveler includes any one of the polymers mentioned above in the embodiments of the present disclosure.

[0170] Any of the above-mentioned polymers refers to any of the polymers involved in the aforementioned embodiments of the polymer and the embodiments of the method for preparing the polymer in the present disclosure.

[0171] In some examples, the leveler has a chemical formula as shown below:

[0172]

[0173] Wherein, 0≤a≤8 (further, 2≤a≤4), 1≤b≤5 (further, 2≤b≤3), 3≤n≤100 (further, 5≤n≤40), and a, b, and n are all integers;

[0174] R is or

[0175] The leveler with the above chemical structure provided by the embodiment of the present disclosure has the function of adjusting the current distribution on the cathode plated part (such as a wafer) at different convection positions (wherein the convection position refers to the position where the flowing electroplating solution passes, and the greater the flow rate of the electroplating solution, the greater the convection intensity). Since the leveler has a strong positive functional group containing N atoms and has a strong positive charge, the N atoms can characteristically adsorb on the high current density area on the cathode plated part, competing with the anode ions, so that the leveler inhibits metal deposition (such as copper deposition) in the high current density area through steric hindrance, and slows down the electroplating speed in the high current density area. At the same time, in the area with greater convection intensity, the leveler has a stronger adsorption on the cathode plated part, and in the area with less convection intensity, the leveler has a relatively weak adsorption on the cathode plated part. In addition, the leveler can adaptively adjust its adsorption on the cathode plated part according to the size of the current density, provide a stronger metal deposition inhibition to the area with greater current density, and provide a weaker metal deposition inhibition to the area with less current density, and finally achieve the purpose of obtaining a highly uniform coating. In particular, the leveling agent can also obtain a coating with high coplanarity at a high current density, which has a positive significance for increasing the plating speed at a high current density while also improving the coplanarity of the coating.

[0176] It can be seen that when the leveling agent provided in the embodiment of the present disclosure is used in the electroplating solution, the contradiction between the electroplating production efficiency and the coplanarity of the coating is effectively solved. Without losing the coplanarity of the coating (for example, the coplanarity of the copper pillars), the electroplating rate can be increased to at least greater than 2 μm / min, and further greater than 4 μm / min. Compared with improving equipment or replacing the electroplating solution system, using the leveling agent provided in the embodiment of the present disclosure to solve the above-mentioned technical problems is more convenient, easy and reliable, and is also beneficial to the maintenance of the electroplating solution.

[0177] When a is 2, 3 or 4, b is 2 or 3, and n is an integer of 5-40, the leveler has a suitable molecular weight and N atom density, so that the leveler can obtain better adsorption capacity on the cathode plated piece.

[0178] In some examples, when a is 2, b is 2, and R is When, the chemical structure of the corresponding leveling agent is as follows:

[0179]

[0180] In some examples, when a is 2, b is 3, and R is When, the chemical structure of the corresponding leveling agent is as follows:

[0181]

[0182] In some examples, when a is 2, b is 3, and R is When, the chemical structure of the corresponding leveling agent is as follows:

[0183]

[0184] In some examples, when a is 4, b is 3, and R is When, the chemical structure of the corresponding leveling agent is as follows:

[0185]

[0186] According to another aspect of the embodiments of the present disclosure, the embodiments of the present disclosure further provide a method for preparing a leveling agent. The method for preparing the leveling agent is the same as the method for preparing any one of the polymers described above in the embodiments of the present disclosure. That is, the desired leveling agent of the embodiments of the present disclosure can be obtained by adopting the same method as the method for preparing any one of the polymers involved in the embodiments of the present disclosure. Therefore, the method for preparing the leveling agent will not be described in detail herein.

[0187] According to another aspect of the embodiments of the present disclosure, the embodiments of the present disclosure further provide an electroplating solution, which includes any one of the above-mentioned leveling agents.

[0188] Any type of leveling agent described above in the embodiments of the present disclosure can be used in the electroplating solution and can achieve a highly uniform coating. At the same time, a highly coplanar coating can also be achieved under high current density.

[0189] It can be seen that the electroplating solution provided in the embodiment of the present disclosure effectively solves the contradiction between electroplating production efficiency and coating coplanarity. Without losing coating coplanarity (such as copper column coplanarity), the electroplating rate can be significantly improved. Compared with improving equipment or replacing the electroplating solution system, using the electroplating solution provided in the embodiment of the present disclosure to solve the above-mentioned technical problems is more convenient, easy and reliable, and is also beneficial to the maintenance of the electroplating solution.

[0190] In some examples, the chemical structure of the leveler is as follows:

[0191]

[0192] Wherein, 0≤a≤8, 1≤b≤5, 3≤n≤100, and a, b, and n are all integers;

[0193] R is or

[0194] The electroplating solution provided by the embodiment of the present disclosure uses the leveling agent of the above chemical structure. The leveling agent has the function of adjusting the current distribution on the cathode plated piece at different convection positions, and can inhibit metal deposition in high current density areas through steric hindrance, thereby slowing down the electroplating speed in high current density areas. The electroplating solution provided by the embodiment of the present disclosure, based on the use of the above leveling agent, is conducive to obtaining a highly uniform coating and is conducive to improving the stability of the electroplating solution. The electroplating solution is suitable for use under high current density, and can effectively improve the coplanarity of the copper pillars while increasing the plating speed under high current density.

[0195] The electroplating solution provided in the embodiment of the present disclosure includes, in addition to the above-mentioned leveling agent, other components, including: metal salt, acid solution, water-soluble chloride, accelerator and inhibitor.

[0196] In some possible implementations, the present disclosure provides an electroplating solution, which includes: a metal salt, an acid solution, a water-soluble chloride, a leveler, an accelerator, and an inhibitor. The following further describes each component:

[0197] For the metal salt, the metal salt is used as an anode component to form a metal coating on the cathode plated part, and the metal coating is the metal to be plated. The metal salt includes but is not limited to copper salts, aluminum salts, silver salts, etc. suitable for electroplating. In particular, the metal salt can be a commonly used copper salt, for example, the copper salt can include at least one of copper sulfate, copper cyanide and copper pyrophosphate. In some examples, the copper salt is copper sulfate.

[0198] The concentration of the metal salt in the electroplating solution is 5g / L-300g / L. For example, the concentration of the metal salt in the electroplating solution includes but is not limited to the following: 10g / L, 50g / L, 100g / L, 110g / L, 120g / L, 130g / L, 140g / L, 150g / L, 160g / L, 170g / L, 180g / L, 190g / L, 200g / L, 210g / L, 220g / L, 230g / L, 240g / L, 250g / L, 260g / L, 270g / L, 280g / L, 290g / L, 300g / L, etc. For further example, the concentration of the metal salt in the electroplating solution is 150g / L-250g / L. The concentration of the metal salt is within the above range, which can not only ensure that sufficient metal ions are provided to the cathode plated parts, but also facilitate the full dissolution of the metal salt in the electroplating solution.

[0199] For the acid solution, the acid solution is used as an electrolyte to promote the redox reaction involved in the electroplating process. In some examples, the acid solution includes at least one of sulfuric acid, hydrochloric acid and an organic acid. For example, the acid solution is sulfuric acid, which can be prepared into an acid solution with a mass concentration of 30%-60% by using concentrated sulfuric acid with a mass concentration of 98% and water.

[0200] The concentration of the acid solution in the electroplating solution is 10g / L-300g / L. For example, the concentration of the acid solution in the electroplating solution includes but is not limited to: 10g / L, 20g / L, 30g / L, 40g / L, 50g / L, 60g / L, 70g / L, 80g / L, 90g / L, 100g / L, 110g / L, 120g / L, 130g / L, 140g / L, 150g / L, 160g / L, 170g / L, 180g / L, 190g / L, 200g / L, 250g / L, 280g / L, etc. For further example, the concentration of the acid solution in the electroplating solution is 50g / L-150g / L. The concentration of the acid solution within the above range can not only ensure the good conductivity of the electroplating solution, but also ensure that the metal salt is fully dissolved in the electroplating solution to avoid precipitation.

[0201] As for the water-soluble chloride, the water-soluble chloride is used as an inorganic additive to provide chloride ions to cooperate with inhibitors, accelerators, etc. In some examples, the water-soluble chloride includes at least one of hydrochloric acid, sodium chloride, potassium chloride and ammonium chloride.

[0202] Taking the concentration of chloride ions as a reference, the concentration of chloride ions in the water-soluble chloride in the electroplating solution is 1ppm-100ppm, for example, 10ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, etc. For further example, the concentration of chloride ions in the water-soluble chloride in the electroplating solution is 40ppm-80ppm. The concentration of the water-soluble chloride within the above range can ensure that the leveler, inhibitor and accelerator can effectively play their due role in the electroplating solution, and also avoid the generation of chlorine gas at the anode to form a side reaction.

[0203] As for the leveling agent, as shown above, the concentration of the leveling agent provided by the embodiment of the present disclosure in the electroplating solution is 0.01ppm-1000ppm, for example, this includes but is not limited to: 0.01ppm, 0.05ppm, 0.1ppm, 0.5ppm, 1ppm, 5ppm, 10ppm, 20ppm, 50ppm, 100ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, etc. For further example, the concentration of the leveling agent in the electroplating solution is 0.1ppm-500ppm, or, further, 0.1ppm-100ppm. The concentration of the leveling agent within the above range is conducive to better synergistic effect with other components in the electroplating solution, has strong adaptability to current density, and has a good uniform plating effect.

[0204] As for the accelerator, the accelerator is used for the formation of crystal nuclei during the electroplating process and improves the throwing power of the electroplating solution. In some examples, the accelerator is at least one of sodium 3,3'-dithiodipropane sulfonate (SPS) and sodium 3-mercaptopropanesulphonate (MPS). The above-mentioned types of accelerators are conducive to making the coating distribution dense, improving the throwing power of the electroplating solution, and making the coating smooth and reflective.

[0205] The concentration of the accelerator in the plating solution is 0.01ppm-100ppm, for example, this includes but is not limited to: 0.01ppm, 0.05ppm, 0.08ppm, 0.1ppm, 0.2ppm, 0.3ppm, 0.5ppm, 0.6ppm, 0.8ppm, 1ppm, 5ppm, 10ppm, 15ppm, 20ppm, 25ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, etc. For further example, the concentration of the accelerator in the plating solution is 0.05ppm-50ppm, or, further, 0.1ppm-20ppm.

[0206] As for the inhibitor, the inhibitor is used to increase the electrochemical reaction resistance, so as to achieve the effect of refining the grains and inhibiting the growth of the coating on the board surface. In some examples, the inhibitor includes at least one of polyethylene glycol, polypropylene glycol, PEO-PPO-PEO block copolymer and PPO-PEO-PPO block copolymer. Among them, PPO (Polypropylene Oxide) is polyoxypropylene, PEO (Polyethylene oxide) is polyoxyethylene, PEO-PPO-PEO block copolymer is also called polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer, and PPO-PEO-PPO block copolymer is also called polyoxypropylene-polyoxyethylene-polyoxypropylene block copolymer. The above-mentioned types of inhibitors are easily adsorbed on the active points of grain growth, increase the electrochemical reaction resistance, and enhance the electrochemical polarization, so as to achieve the effect of refining the grains and inhibiting the growth of the coating on the board surface.

[0207] The concentration of the inhibitor in the plating solution is 1ppm-2000ppm, for example, this includes but is not limited to: 1ppm, 5ppm, 10ppm, 15ppm, 20ppm, 30ppm, 40ppm, 50ppm, 60ppm, 70ppm, 80ppm, 90ppm, 100ppm, 200ppm, 300ppm, 400ppm, 500ppm, 600ppm, 700ppm, 800ppm, 900ppm, 1000ppm, 1500ppm, etc. For further example, the concentration of the inhibitor in the plating solution is 50ppm-1500ppm, or, further, 100ppm-1000ppm.

[0208] The electroplating solution provided by the embodiments of the present disclosure having the above-mentioned components can effectively adjust the distribution of current during the electroplating process through the synergistic effect of metal salts, acid solution, water-soluble chloride, leveling agent, accelerator and inhibitor, significantly improve the dispersibility and throwing power of the electroplating solution, and obtain a highly coplanar coating, such as a copper pillar. In particular, the electroplating solution is suitable for use at high current density, and can still obtain a highly coplanar coating at high current density and high plating speed.

[0209] The electroplating solution provided in the embodiments of the present disclosure is suitable for forming a metal coating with uniform thickness on a substrate. For example, the substrate includes but is not limited to a printed circuit board, an integrated circuit, a semiconductor package, a lead frame and an interconnection. The electroplating solution provided in the embodiments of the present disclosure is suitable for the field of microelectronic packaging. For example, it can be used for electroplating of copper pillars in microelectronic packaging interconnections, effectively improving the coplanarity of the copper pillars under high current density, thereby effectively improving the service life and reliability of electronic devices.

[0210] According to another aspect of the embodiments of the present disclosure, the embodiments of the present disclosure also provide a method for electroplating a plated component, wherein the method uses the above-mentioned electroplating solution.

[0211] The plated part is a cathode plated part, and its material includes but is not limited to: resin, ceramic, metal, silicon chip (i.e. wafer), etc. For example, a cathode plated part can be prepared by using resin, and the cathode plated part can be used as a printed circuit board; or, a cathode plated part can be prepared by using ceramic, and the cathode plated part can be used as a semiconductor chip; or, a cathode plated part can be prepared by using metal silicon, and the cathode plated part can be used as a wafer.

[0212] By using the electroplating solution provided in the embodiment of the present disclosure for electroplating, a highly uniform coating can be obtained. In particular, even under high current density and high plating speed conditions, a highly uniform coating can still be obtained, and a high electroplating efficiency is ensured.

[0213] In some examples, the method for electroplating a plated part provided by the embodiments of the present disclosure includes: performing the electroplating at a current density greater than or equal to 5 ASD, for example, greater than or equal to 10 ASD. Further, the electroplating is performed at a current density greater than or equal to 15 ASD, for example, greater than or equal to 16 ASD, greater than or equal to 17 ASD, greater than or equal to 18 ASD, greater than or equal to 19 ASD, greater than or equal to 20 ASD, etc.

[0214] In some examples, the method for electroplating a plated part provided by the embodiments of the present disclosure includes performing electroplating at a plating rate ≥ 2 μm / min.

[0215] It can be seen that the electroplating method provided in the embodiment of the present disclosure is suitable for use under high current density and can obtain a coating with high coplanarity.

[0216] In some examples, the embodiments of the present disclosure use a silicon wafer as a cathode plated object and copper ions as the metal to be plated, and perform electroplating in the above-mentioned electroplating solution, so as to form highly coplanar copper columns on the silicon wafer, and the current density during electroplating is greater than 5ASD, and further, greater than or equal to 15ASD; the plating speed is greater than 2μm / min, and further, the plating speed is greater than 4μm / min.

[0217] The present disclosure will be further described below by more specific examples. Although some specific embodiments are described below, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in the art or the product instructions are used, and where the manufacturers of the reagents or instruments are not indicated, they can all be conventional products that can be obtained commercially.

[0218] Example 1

[0219] This embodiment 1 provides a polymer, which is prepared by the following method:

[0220] 3 g of 1,4-butanediol diglycidyl ether was dissolved in 20 ml of ethanol and stirred to obtain an intermediate mixed solution. Under stirring, 1.93 g of N-(3-aminopropyl)morpholine was added to the intermediate mixed solution and stirred to obtain a reaction raw material solution.

[0221] The reaction raw material liquid was heated to 65° C., and then a polymerization reaction was carried out at this temperature. After the polymerization reaction for 24 hours, the reaction system was cooled to room temperature to obtain a yellow viscous solution.

[0222] The yellow viscous solution was subjected to reduced pressure rotary evaporation to remove ethanol to obtain the polymer.

[0223] Example 2

[0224] This embodiment 2 provides a polymer, which is prepared by the following method:

[0225] 3 g of 1,4-butanediol diglycidyl ether was dissolved in 20 ml of ethanol and stirred to obtain an intermediate mixed solution. Under stirring, 1.9 g of N-(3-aminopropyl)pyrrolidine was added to the intermediate mixed solution and stirred to obtain a reaction raw material solution.

[0226] The reaction raw material liquid was heated to 67° C., and then a polymerization reaction was carried out at this temperature. After the polymerization reaction for 24 hours, the reaction system was cooled to room temperature to obtain a yellow viscous solution.

[0227] The yellow viscous solution was subjected to reduced pressure rotary evaporation to remove ethanol to obtain the polymer.

[0228] Example 3

[0229] This embodiment 3 provides a polymer, which is prepared by the following method:

[0230] 2.8 g of 1,6-hexanediol diglycidyl ether was dissolved in 30 ml of methanol and stirred to obtain an intermediate mixed solution. Under stirring, 1.93 g of N-(3-aminopropyl)morpholine was added to the intermediate mixed solution and stirred to obtain a reaction raw material solution.

[0231] The reaction raw material liquid was heated to 70° C., and then a polymerization reaction was carried out at this temperature. After the polymerization reaction lasted for 24 hours, the reaction system was cooled to room temperature to obtain a yellow viscous solution.

[0232] The yellow viscous solution was subjected to reduced pressure rotary evaporation to remove methanol to obtain the polymer.

[0233] Test Case

[0234] The polymers provided in Examples 1 to 3 are used as leveling agents in the electroplating solution (i.e., each of the above polymers is a leveling agent), and some electroplating solutions are provided for electroplating as test examples (corresponding to Test Example 1, Test Example 2, and Test Example 3, respectively). At the same time, some electroplating solutions are provided for electroplating as comparative examples (corresponding to Comparative Example 1 and Comparative Example 2, respectively) to test the leveling effect of the leveling agents corresponding to Examples 1 to 3 on the coating at a high current density.

[0235] Among them, the above-mentioned electroplating is actually a copper plating process, using a silicon wafer (referred to as silicon wafer) as a cathode, and electroplating copper columns on the silicon wafer. The electroplating process adopts a hanging plating process.

[0236] The formulas, electroplating conditions, and the electroplated copper pillar morphology and copper pillar array coplanarity results of the test examples and comparative examples are shown in Table 1. The copper sulfate in Table 1 is copper sulfate pentahydrate; the chloride ions in Table 1 are all provided by sodium chloride; and the EPE in Table 1 is a PEO-PPO-PEO block copolymer with a molecular weight of 6000.

[0237] Table 1

[0238]

[0239] The data related to "copper pillar uniformity" in Table 1 refers to the value obtained by dividing the difference between the height of the middle of the copper pillar and the height of the copper pillar shoulder by the height of the copper pillar shoulder.

[0240] The data related to “surface roughness” in Table 1 refers to the surface smoothness of the copper pillar.

[0241] The data related to "copper pillar array coplanarity" in Table 1 refers to the value obtained by dividing the difference between the heights of the highest copper pillar and the lowest copper pillar in the electroplating area by the average height of the copper pillars in this area and then dividing by 2.

[0242] The morphology of the copper pillar obtained by test example 1 is shown in Figure 1 The morphology and structure of the copper pillar obtained by Test Example 2 can be seen in Figure 2 The morphology and structure of the copper pillar obtained by Test Example 3 are shown in Figure 3 The morphology and structure of the copper column obtained by comparative example 1 are shown in Figure 4 The morphology and structure of the copper column obtained by comparative example 2 are shown in Figure 5 .

[0243] like Figure 1-Figure 3 From the copper plating results in Table 1, it can be seen that the electroplating solutions provided in Test Examples 1 to 3 are as high as 15A / dm 2 , even up to 20A / dm 2 Under current density of , high coplanarity copper pillars can be obtained. Figure 4 and Figure 5 Compared with Comparative Examples 1 and 2, the addition of the leveler of the embodiment of the present disclosure to the electroplating solution can greatly improve the uniformity of a single copper pillar and the coplanarity of the copper pillar array, which confirms that the electroplating solution provided by the embodiment of the present disclosure is conducive to obtaining highly uniform copper pillars under high current density.

[0244] In addition, it can be seen from Table 1 that when the deposition rate of the copper column is 4.4 μm / min, the uniformity of the copper column can be maintained within 5% (wherein, when the current density is 20 ASD, the theoretical growth rate of the copper column is about 4.4 μm / min).

[0245] The above description is only for the purpose of facilitating those skilled in the art to understand the technical solution of the present disclosure and is not intended to limit the present disclosure. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A polymer, It is characterized in that The polymer comprises a plurality of repeating units, wherein the repeating units comprise: a binary epoxy compound residue group and a nitrogen-containing group; The binary epoxy compound residue group is a residue formed after the epoxy bond of the binary epoxy compound is opened; The nitrogen-containing group includes: an alkyl group, a dimethylamino group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamino group is also connected to the divalent epoxy compound residue group through a single bond, the nitrogen-containing heterocyclic group is a morpholine group or a pyrrolyl group, and the nitrogen-containing heterocyclic group is connected to the alkyl group through a nitrogen atom.

2. The polymer according to claim 1, It is characterized in that The alkyl group has 1-5 carbon atoms.

3. The polymer according to claim 1, It is characterized in that The chemical structural formula of the nitrogen-containing group includes: or Wherein, b is an integer, and 1≤b≤5.

4. The polymer according to claim 1, It is characterized in that The binary epoxy compound residue group comprises: a non-epoxy linking group, and two epoxy residues respectively connected to both ends of the non-epoxy linking group; The epoxy residue is a residue formed after the epoxy bond is opened, and the epoxy residue is connected to the dimethylamine group.

5. The polymer according to claim 4, It is characterized in that The chemical structural formula of the binary epoxy compound residue group is one of the following chemical structural formulas: or Among them, a 1 、a 2 、a 3 、a 4 are all integers, and are individually integers from 0 to 8.

6. The polymer according to any one of claims 1 to 5, It is characterized in that The number of the repeating units is 3-100.

7. The polymer according to claim 6, It is characterized in that The chemical structural formula of the polymer is shown below: Wherein, 0≤a≤8, 1≤b≤5, 3≤n≤100, and a, b, and n are all integers; R is or 8. A method for preparing a polymer, It is characterized in that The polymer comprises a plurality of repeating units, wherein the repeating units comprise: a binary epoxy compound residue group and a nitrogen-containing group; the nitrogen-containing group comprises: an alkyl group, a dimethylamine group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, and the dimethylamine group is further connected to the binary epoxy compound residue group through a single bond; The preparation method of the polymer comprises: subjecting a binary epoxy compound and a nitrogen-containing compound to a polymerization reaction in a solvent to obtain the polymer; Wherein, the residue formed after the ring-opening of the epoxy bond of the binary epoxy compound serves as the binary epoxy compound residue group; The nitrogen-containing compound includes: an alkyl group, an amine group and a nitrogen-containing heterocyclic group respectively connected to both ends of the alkyl group, the residue formed after the amine group of the nitrogen-containing compound participates in the polymerization reaction serves as the nitrogen-containing group, the nitrogen-containing heterocyclic group is a morpholine group or a pyrrolyl group, and the nitrogen-containing heterocyclic group is connected to the alkyl group through a nitrogen atom.

9. The method for preparing a polymer according to claim 8, It is characterized in that The alkyl group has 1-5 carbon atoms.

10. The method for preparing a polymer according to claim 8, It is characterized in that The chemical structural formula of the nitrogen-containing compound includes: or Wherein, b is an integer, and 1≤b≤5.

11. The method for preparing a polymer according to claim 8, It is characterized in that The binary epoxy compound comprises: a non-epoxy connecting group and two epoxy groups respectively connected to both ends of the non-epoxy connecting group.

12. The method for preparing a polymer according to claim 11, It is characterized in that The chemical structural formula of the binary epoxy compound is one of the following chemical structural formulas: or Among them, a 1 、a 2 、a 3 、a 4 are all integers, and are individually integers from 0 to 8.

13. A method for preparing a polymer according to any one of claims 8 to 12, It is characterized in that The reaction temperature of the polymerization reaction is 60°C-75°C.

14. A method for preparing a polymer according to any one of claims 8 to 12, It is characterized in that The solvent includes at least one of ethanol, methanol and water.

15. Use of the polymer according to any one of claims 1 to 7 in the preparation of a leveling agent.

16. A leveling agent, It is characterized in that The leveler comprises the polymer according to any one of claims 1 to 7.

17. The leveling agent according to claim 16, It is characterized in that The chemical structural formula of the polymer is shown below: Among them, 2≤a≤4, 2≤b≤3, 5≤n≤40; R is or 18. A method for preparing a leveling agent, It is characterized in that The method for preparing the leveling agent is the method for preparing the polymer according to any one of claims 8 to 14.

19. An electroplating solution, It is characterized in that The electroplating solution comprises the leveler according to claim 16 or 17.

20. The electroplating solution according to claim 19, It is characterized in that The electroplating solution also includes: a metal salt, an acid solution, a water-soluble chloride, an accelerator and an inhibitor; Wherein, the concentration of the metal salt in the electroplating solution is 5g / L-300g / L; The concentration of the acid solution in the electroplating solution is 10 g / L-300 g / L; The concentration of chloride ions in the water-soluble chloride in the electroplating solution is 1ppm-100ppm; The concentration of the leveler in the electroplating solution is 0.01ppm-1000ppm; The concentration of the accelerator in the electroplating solution is 0.01ppm-100ppm; The concentration of the inhibitor in the plating solution is 1 ppm-2000 ppm.

21. The electroplating solution according to claim 20, It is characterized in that The metal salt includes at least one of copper sulfate, copper cyanide and copper pyrophosphate; The acid solution includes at least one of sulfuric acid, hydrochloric acid and an organic acid; The water-soluble chloride includes at least one of hydrochloric acid, sodium chloride, potassium chloride and ammonium chloride.

22. The electroplating solution according to claim 20 or 21, It is characterized in that The accelerator includes at least one of sodium polydisulfide propane sulfonate and sodium 3-mercapto-1-propane sulfonate; The inhibitor includes at least one of polyethylene glycol, polypropylene glycol, a PEO-PPO-PEO block copolymer, and a PPO-PEO-PPO block copolymer.

23. A method for electroplating a plated part, It is characterized in that The method comprises: using the electroplating solution according to any one of claims 19-22.

24. The method for electroplating a plated article according to claim 23, It is characterized in that The method includes: performing the electroplating at a current density greater than or equal to 5 ASD.

25. The method for electroplating a plated article according to claim 24, It is characterized in that The method includes: performing the electroplating at a current density greater than or equal to 15 ASD.

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