Plating solution additives

Abstract

The present invention provides an additive for a plating solution that provides excellent filling properties, a plating solution containing the additive, and a method for manufacturing an electronic substrate using the plating solution. [Solution] A method for manufacturing an electronic substrate, comprising: a plating solution additive containing a sulfone compound having a specific structure including a sulfonyl group and two or more nitrogen-containing functional groups; a plating solution containing the plating solution additive and metal ions; and a step of plating a substrate using the plating solution. The sulfone compound is a compound selected from the group consisting of an ethylene group, a (poly)alkyleneoxy group, a -CH2-C(=O)-NH(CH2)2NH-C(=O)-CH2- group, a -CH2-C(=O)-NH(CH2)3NH-C(=O)-CH2- group, a -N + (CH3)2-Za-N + It preferably has a group selected from a (CH3)2- group (Za is a (poly)alkyleneoxy group substituted with a hydroxy group) and a propylene group substituted with a hydroxy group.

Description

[Technical Field]

[0001] The present invention relates to a plating solution additive. More specifically, the present invention relates to a plating solution additive containing a compound having a nitrogen-containing sulfonyl structure, a plating solution containing the plating solution additive, and a method for producing an electronic substrate using the plating solution. [Background technology]

[0002] In the field of electronic materials, plating technology for forming metals on substrates is widely used, and its range of applications extends to electronic devices such as liquid crystal displays and semiconductor devices. High-precision, uniform metal plating is particularly required in processes such as forming fine circuits and wiring layers, and forming metal layers on semiconductor wafers. To meet these requirements, copper, which has excellent conductivity and workability, is primarily used as a plating material.

[0003] In the manufacture of printed wiring boards, it is necessary to uniformly fill gaps between wiring and holes such as via holes with metal such as copper. The manufacture of semiconductor wafers also involves a process of filling tiny vias and trenches formed on the wafer surface with metal. In particular, in substrate lamination methods such as the build-up method, the importance of filling connection holes between layers, known as filling plating, is increasing, and high-precision metal filling technology is required.

[0004] Electrolytic plating is the main metal embedding technique typified by filling plating, and uses an acid copper plating solution, an alkaline cyanide copper plating solution, a copper pyrophosphate plating solution, etc. In particular, acid plating solutions containing copper sulfate as the main component are advantageous in terms of ease of solution management and adjustment of the electrodeposition rate, and are widely used in a variety of applications, such as wiring formation and via filling.

[0005] The plating solution used for filling plating contains metal salts as well as organic additives called levelers (leveling agents), as well as acids and surfactants. Levelers play a role in controlling the deposition behavior and electrodeposition properties of plating, filling vias, trenches, and gaps between wiring, enabling uniform plating. Nitrogen-containing compounds are often used as levelers (for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-105584 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-183410 [Patent Document 3] International Publication No. 2011 / 135716 [Patent Document 4] International Publication No. 2023 / 166552 Summary of the Invention [Problem to be solved by the invention]

[0007] In the recent manufacture of printed wiring boards and semiconductor wafers, it is required to completely fill gaps by plating and achieve a high level of planarization. The plating solutions disclosed in Patent Documents 1 and 2 have difficulty achieving such a high level of planarization, and are not necessarily applicable to processes such as copper plating. Although these issues are resolved by the levelers disclosed in Patent Documents 3 and 4, further improvements in plating performance, particularly filling characteristics, are required.

[0008] The present invention has been made in view of the above circumstances, and aims to provide a plating solution additive that provides excellent filling properties, a plating solution containing the plating solution additive, and a method for manufacturing an electronic substrate using the plating solution. [Means for solving the problem]

[0009] The present inventors have discovered that a plating solution with excellent filling properties can be obtained by adding a compound having a specific nitrogen-containing sulfonyl structure to the plating solution, and have thus completed the present invention.

[0010] That is, the present invention provides the following (1) to (8). (1) A compound having a nitrogen-containing sulfonyl structure represented by the following formula 1: Additive for plating solution. [ka] (In formula 1, X is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, a substituted or unsubstituted arylene group, or a group represented by formula 2 or formula 3, which may have any of a linear, branched, or cyclic structure; Y is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted (poly)alkyleneimino group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted araryl group, which may have any of a linear, branched, or cyclic structure; R 1 is an alkylene group; a+b R 2 may be the same or different and are a hydrogen atom or an alkyl group; a and b are each independently 1 or 2. [ka] (In Formula 2 and Formula 3, R 3 is a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted araryl group, which may have a linear, branched, or cyclic structure; R 3 When there are a plurality of R, they may be the same or different; Z is a substituted or unsubstituted (poly)alkyleneoxy group, which may have a linear, branched, or cyclic structure; c+d R4 may be the same or different and are a hydrogen atom or an alkyl group; c and d are each independently 1 or 2. (2) The compound contains a nitrogen-containing sulfonyl structure represented by the following formula 4: The plating solution additive described above in (1). [ka] (In formula 4, X, Y, R 1 , R 2 a and b are the same as those in Formula 1 above; e is 1 or 2, independently of a and b; and a plurality of R 1 and R 2 may be the same or different.) (3) The compound has a structure in which the nitrogen-containing sulfonyl structure is bridged via the group in X and / or Y in the formula 1. The plating solution additive according to (1) or (2) above. (4) In the compound, X in the formula 1 is an ethylene group, a (poly)ethyleneoxy group, a (poly)propyleneoxy group, a -CH2-C(=O)-NH(CH2)2NH-C(=O)-CH2- group, a -CH2-C(=O)-NH(CH2)3NH-C(=O)-CH2- group, a -N + (CH3)2-Za-N + a group selected from a (CH3)2- group (Za is a (poly)alkyleneoxy group substituted with a hydroxy group) and a propylene group substituted with a hydroxy group; The plating solution additive according to any one of (1) to (3) above. (5) The plating solution additive according to any one of the above (1) to (4), wherein Y in formula 1 is a (poly)alkyleneoxy group. (6) The compound further has a hydroxy group-containing (poly)alkyleneoxy group, a glycidyl group, a halogenated hydrocarbon group, and / or a sulfonate ester group. The plating solution additive according to any one of (1) to (5) above. (7) The weight average molecular weight (Mw) of the compound is 300 or more and 50,000 or less. The plating solution additive according to any one of (1) to (6) above. (8) metal ions, and a plating solution additive according to any one of (1) to (7) above, Plating solution. (9) The metal ions include copper ions. The plating solution (8) above. (10) The plating solution additive contains the compound constituting the plating solution additive at a concentration of 0.5 mg / L to 1000 mg / L. The plating solution according to (8) or (9) above. (11) A method for manufacturing a method for plating a substrate using the plating solution according to any one of (8) to (10) above. Manufacturing method for electronic substrates. [Effects of the Invention]

[0011] The plating solution additive of the present invention and the plating solution containing it exhibit excellent filling properties. DETAILED DESCRIPTION OF THE INVENTION

[0012] Specific embodiments of the present invention will be described in detail below, but the present invention is not limited to these embodiments.

[0013] ≪1. Plating solution additives≫ The present embodiment is an additive for a plating solution that contains a compound having a nitrogen-containing sulfonyl structure represented by formula 1 (hereinafter, sometimes referred to as a "nitrogen-containing sulfone compound"). [ka] (In formula 1, X is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, a substituted or unsubstituted arylene group, or a group represented by formula 2 or formula 3, which may have any of a linear, branched, or cyclic structure; Y is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted (poly)alkyleneimino group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted araryl group, which may have any of a linear, branched, or cyclic structure; R 1 is an alkylene group; a+b R 2 may be the same or different and are a hydrogen atom or an alkyl group; a and b are each independently 1 or 2. [ka] (In Formula 2 and Formula 3, R 3 is a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted araryl group, which may have a linear, branched, or cyclic structure; R 3 When there are a plurality of R, they may be the same or different; Z is a substituted or unsubstituted (poly)alkyleneoxy group, which may have a linear, branched, or cyclic structure; c+d R 4 may be the same or different and are a hydrogen atom or an alkyl group; c and d are each independently 1 or 2.

[0014] The plating solution additive of this embodiment provides excellent filling properties. The main components of the plating solution additive of this embodiment will be described in detail below.

[0015] <1-1. Nitrogen-containing sulfone compounds> The plating solution additive of this embodiment is characterized by containing a compound (nitrogen-containing sulfone compound) having a nitrogen-containing sulfonyl structure represented by the above formula 1. Note that the two nitrogen atoms in formulas 1 and 3 may both be imino groups having a -N< structure, or both may be >N + <structure, or one may be an imino group and the other an ammonium-containing group. That is, the nitrogen-containing sulfonyl structure represented by formula 1 includes various nitrogen-containing sulfonyl structures represented by the following formulae 1a to 1d, and the group represented by formula 3 includes various groups represented by the following formulae 3a to 3d. In formulae 1a to 1d and 3a to 3d, X, Y, Z, and R 1 ~R 4 is the same as in the above formula 1 and formula 3. [ka] [ka]

[0016] In X and Y in Formula 1, the "(poly)alkyleneoxy group" may be any divalent group having an alkylene and an oxygen atom, and there is no particular limitation on the number of alkyleneoxy groups. Examples include a methylenedioxy group (-O-CH2-O-), an ethylenedioxy group (-O-CH2CH2-O-), a propylenedioxy group (-O-CH2CH2CH2-O-, -O-CH(CH3)CH2-O-), a butylenedioxy group (-O-CH2CH2CH2CH2-O-, etc.), a polyethyleneoxy group (-O-(CH2CHO) n -: n is an integer of 2 or more, for example, -OC2H4OC2H4OC2H4OC2H4O-, etc.), polypropyleneoxy group (-O-[CH(CH3)CH2O] n - (n is an integer of 2 or more), polybutyleneoxy group, etc., but are not limited to these. Groups having multiple structures such as -OCH2CH2OCH(CH3)CH2O- may also be used.

[0017] In the formula 1, Y may be any divalent group having an alkylene and an imino group (-NH-), and the hydrogen on the nitrogen atom may be substituted with an alkyl group such as a methyl group. Examples include an iminodiethylidyl group (-CHNHCH-), an iminodipropylidyl group (-CHNHCH-), and a polyethyleneimino group (-(CHCHN) n Examples include, but are not limited to, CH2CH2-: n is an integer of 2 or more, for example, -C2H4NHC2H4NHC2H4-.

[0018] X, Y, and R in Formula 1 1 and R in Formula 2 and Formula 3 3 In the above, the alkylene group, arylene group, aralkylene group, and ararylene group are not particularly limited and include groups of various structures and carbon atoms. Specific examples of the alkylene group include groups having 1 to 20 carbon atoms, particularly 2 to 8 carbon atoms, such as methylene group, ethylene group, propylene group, isopropylene group, butylene group, isobutylene group, pentylene group, hexylene group, octylene group, isooctylene group, and cyclohexylene group. Specific examples of the arylene group include groups having 6 to 20 carbon atoms, particularly 6 to 10 carbon atoms, such as phenylene group, naphthylene group, and biphenylene group. Specific examples of the aralkylene group include groups having 7 to 20 carbon atoms, particularly 8 to 12 carbon atoms, such as phenylmethylene group and phenylethylene group. Specific examples of the araryl group include groups having 7 to 20 carbon atoms, particularly 8 to 14 carbon atoms, such as xylylenediyl group. It should be noted that the alkylene group and the like are not limited to these specific examples.

[0019] X and Y in Formula 1, and R in Formulas 2 and 3 3In the above, the (poly)alkyleneoxy group, (poly)alkyleneimino group, alkylene group, arylene group, aralkylene group, and ararylene group may each have a substituent such as an alkyl group, a hydroxy group, or a nitrogen-containing functional group. Furthermore, they may be bonded to other molecules or have intramolecular crosslinking points via these substituents such as hydroxy groups. That is, the sulfone compound may have a structure in which a nitrogen-containing sulfonyl structure is crosslinked via a group in X and / or Y.

[0020] R in Equation 1 2 is a hydrogen atom or an alkyl group, for example, an alkyl group having 1 to 6 carbon atoms. 2 is preferably a hydrogen atom or a methyl group.

[0021] The compound having the nitrogen-containing sulfonyl structure represented by Formula 1 can function as, for example, a leveler (leveling agent, smoothing agent) in a plating solution. Therefore, a plating solution containing such a nitrogen-containing sulfone compound has excellent filling properties. In some cases, the plating surface can be planarized.

[0022] Although the present invention is not limited by any particular theory, it is believed that the excellent filling properties achieved by the addition of the plating solution additive of this embodiment are brought about by the structure represented by Formula 1. As will be shown in the Examples and Comparative Examples described later, nitrogen-containing compounds that do not have a sulfonyl group do not exhibit good filling properties. Furthermore, even in nitrogen-containing compounds that have a sulfonyl group, sufficient filling properties cannot be obtained if the nitrogen atom is fixed in a ring structure rather than on the main chain. In contrast, the mechanism by which the nitrogen-containing sulfonyl structure represented by Formula 1 exhibits its effects is unknown, but it is thought that the sulfonyl group may be activated by the nitrogen atom on the same main chain.

[0023] (Preferred Nitrogen-Containing Sulfone Compounds) Considering the above possibilities, it is preferable that the nitrogen-containing sulfone compound has multiple sulfonyl groups and nitrogen-containing functional groups on the main chain in order to further improve the filling property of the plating solution. One example is a compound having a nitrogen-containing sulfonyl structure represented by the following formula 4: [ka]

[0024] In Equation 4, X, Y, and R 1 , R 2 a and b are the same as those in Formula 1 above; e is 1 or 2, independently of a and b; and a plurality of R 1 and R 2 may be the same or different. Compounds having a nitrogen-containing structure with two sulfonyl groups may be more likely to exhibit the filling properties attributable to the sulfonyl groups. The nitrogen-containing sulfonyl structures represented by Formula 1 and Formula 4 may have a crosslinked structure via a group in X and / or Y, such as a hydroxy group.

[0025] In nitrogen-containing sulfone compounds, the number of sulfonyl groups (-SO2-) is also proportional to the number of nitrogen-containing functional groups (-N<, >N + In order to further improve the filling properties of the plating solution, it is preferable that the ratio of the number of groups is 1:1 to 1:5, preferably 2:3 to 1:4, and particularly preferably about 1:2 to 1:3. In particular, if the compound contains nitrogen-containing functional groups in a molar amount twice or more that of the sulfonyl group on the same main chain, the sulfonyl group is more activated, making it easier to exhibit even better filling properties. From the same perspective, it is preferable that X in the above formula 1 or 3 has a nitrogen-containing sulfonyl structure, which is a group represented by formula 2 and / or formula 3.

[0026] In the nitrogen-containing sulfone compound, X in formula 1 and formula 3 represents a group having a linear structure, particularly an ethylene group, a (poly)ethyleneoxy group, a (poly)propyleneoxy group, a -CH2-C(=O)-NH(CH2)2NH-C(=O)-CH2- group, a -CH2-C(=O)-NH(CH2)3NH-C(=O)-CH2- group, a -N+ (CH3)2-Za-N + It is preferably a group selected from a (CH3)2- group (Za is a (poly)alkyleneoxy group substituted with a hydroxy group) and a propylene group substituted with a hydroxy group. Among these, particularly preferred are a -CH2-C(=O)-NH(CH2)2NH-C(=O)-CH2- group, a -CH2-C(=O)-NH(CH2)3NH-C(=O)-CH2- group, and a -N + (CH3)2-Za-N + A (CH3)2- group (Za is a (poly)alkyleneoxy group substituted with a hydroxy group) is preferred.

[0027] The nitrogen-containing sulfone compound also preferably has a linear structure, and preferably has a structure that allows easy bending around the nitrogen atom in Formula 1. In particular, it is preferable that Y in Formula 1 is a (poly)alkyleneoxy group, particularly a poly(ethyleneoxy) group. The reason for this is unclear, but even if Y has a (poly)alkyleneoxy group or a ring structure such as a benzene ring, if it has an easy-to-bend structure in which it is bonded to the nitrogen atom via an alkyl group or an oxy group, the adjacent nitrogen functional group may also be easily mobile, which may facilitate interaction with the nearby sulfonyl group.

[0028] (Specific Examples of Nitrogen-Containing Sulfonyl Structures) Among the nitrogen-containing sulfonyl structures (hereinafter sometimes referred to as "NS-containing structures"), specific examples of preferred structures include, but are not limited to, the following: In the nitrogen-containing sulfonyl structures of the following formulas, the position marked with "*" indicates a terminal single bond in each structure. [ka] [ka]

[0029] Among the above, NS-containing structures-1, 2, 5, 6, 15 to 17, and 19 to 23 are preferred, and NS-containing structures-1, 2, 5, 6, 15 to 17, 19, 20, and 22 are particularly preferred. A plurality or a plurality of types of these nitrogen-containing sulfonyl structures may be linked to form the compound of this embodiment, and the site marked with "*" may be bonded to a hydrogen atom, an alkyl group, or the like, or may form a terminal group such as a vinyl group or an allyl group. When a plurality or a plurality of types of nitrogen-containing sulfonyl structures are linked, there is no particular limitation on the number.

[0030] (Molecular weight of nitrogen-containing sulfone compound) As shown in the above specific examples, the nitrogen-containing sulfonyl structure may have a relatively long chain length. In other words, the nitrogen-containing sulfone compound may be a compound with a relatively large molecular weight. There are no particular restrictions on the molecular weight of the nitrogen-containing sulfone compound, but the weight-average molecular weight is preferably 300 to 50,000, more preferably 500 to 20,000, even more preferably 1,000 to 15,000, and particularly preferably 2,000 to 10,000. The molecular weight of the nitrogen-containing sulfone compound can be measured, for example, by gel permeation chromatography (GPC) using monodisperse polyethylene oxide or polyethylene glycol as a standard. It may also be measured by analytical methods such as light scattering or mass spectrometry.

[0031] <1-2. Preparation of nitrogen-containing sulfone compounds> The compound having a nitrogen-containing sulfonyl structure represented by formula 1 can be prepared by reacting a sulfone compound having a C=C double bond-containing group, such as a vinyl group or an allyl group, with a primary or secondary diamine. An example of such a reaction is shown in the following reaction scheme 1. Of course, these nitrogen-containing sulfone compounds can also be prepared using starting materials and reaction routes other than those shown in reaction scheme 1. [ka]

[0032] Here, there is no particular limitation on the sulfone compound and diamine used as raw materials, and the group X capable of generating X o and R 1 a sulfone compound having a group capable of forming Y and R 2 Any diamine compound having the formula:

[0033] Specifically, the nitrogen-containing sulfone compound having the above-mentioned NS structure-1 is prepared from the following sulfone compound raw material-1 and diamine compound-1. [ka]

[0034] In addition, a third or even fourth compound may be used in combination with the sulfone compound and diamine compound described above to introduce a third structural unit, or even a fourth or subsequent structural unit, into the nitrogen-containing sulfonyl structure. For example, a (poly)epoxy compound such as glycidyl ether, a (poly)halogenated hydrocarbon such as an alkyl halide, or a halide such as polyoxyalkylene halide may be reacted, or a sulfone compound such as a sulfonic acid ester such as polyalkyleneoxysulfonate and / or a diamine compound may be used in combination. Alternatively, a compound having an ether bond (e.g., a polyoxyethylene group) in the nitrogen-containing sulfonyl structure can be prepared using divinyl sulfone (CHCH-SO-CHCH) or the like as a sulfone compound raw material, CHNHCH or the like as a diamine compound, and a diepoxy compound.

[0035] This embodiment also encompasses embodiments in which the nitrogen-containing sulfone compound further comprises a hydroxyl group-containing (poly)alkyleneoxy group, a glycidyl group, a halogenated hydrocarbon group, and / or a sulfonate ester group. The hydroxyl group-containing (poly)alkyleneoxy group or glycidyl group can be introduced, for example, by reacting with the above-mentioned (poly)epoxy compound. The halogenated hydrocarbon group can be introduced, for example, by reacting with a halide such as a (poly)halogenated hydrocarbon or a polyoxyalkylene halide. The sulfonate ester group can be introduced as a group having a structure different from the above-mentioned nitrogen-containing sulfonyl structure, for example, by using multiple sulfone compounds in combination. These groups may be divalent, monovalent, or trivalent or higher. For example, a monovalent halogenated alkyl group or a glycidyl group can be introduced as a terminal group. The halogenated hydrocarbon group or the like may be bonded via an oxygen atom or the like.

[0036] The synthesis reaction shown in Reaction Scheme 1 can be carried out, for example, using a water solvent under atmospheric pressure at a temperature of 10 to 100°C, particularly 30 to 50°C. The structure of the nitrogen-containing sulfone compound produced by the reaction is 1 H-NMR, 13 The compound can be identified by analytical methods such as C-NMR, infrared absorption spectroscopy (IR), mass spectroscopy (MS), and elemental analysis.

[0037] <1-3. Other ingredients> The plating solution additive of this embodiment may contain other components in addition to the nitrogen-containing sulfone compound. For example, it may be a mixture of the nitrogen-containing sulfone compound and a general-purpose plating solution additive such as a brightener, a suppressor, an acid, a halide ion, a complexing agent, an antioxidant, a conductive salt, a wetting agent, or a dye. However, from the standpoints of ease of preparation and storage stability, it is preferable to add these plating solution additives at the plating solution preparation stage. Therefore, these additives will be described later as components of the plating solution.

[0038] 2. Plating Solution The present embodiment provides a plating solution containing metal ions and the above-described plating solution additive. The plating solution additive of the present embodiment exhibits excellent filling properties. The components of the plating solution of the present embodiment will be described below.

[0039] <2-1. Metal ions> The metal ions contained in the plating solution of this embodiment are not particularly limited, but examples include ions of copper (Cu), tin (Sn), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), cobalt (Co), zinc (Zn), silver (Ag), gold (Au), platinum (Pt), palladium (Pd), indium (In), molybdenum (Mo), tungsten (W), lead (Pb), rhenium (Re), rhodium (Rh), ruthenium (Ru), osmium (Os), iridium (Ir), bismuth (Bi), and aluminum (Al). Metalloid ions such as germanium (Ge), arsenic (As), and antimony (Sb) are also included. The metal ions may also be complex ions. Multiple metal ions may be used in combination to form an alloy plating solution. In the plating solution of this embodiment, the metal ions preferably include copper ions.

[0040] The metal ions in the plating solution according to this embodiment are usually obtained by dissolving a metal salt in a solvent such as water. The plating solution according to this embodiment is preferably obtained by dissolving a copper-containing metal salt in water. The copper-containing metal salt is not particularly limited, but examples thereof include copper sulfate, copper pyrophosphate, and copper acetate. Among these, copper sulfate is preferred. Furthermore, when copper sulfate is used, copper sulfate pentahydrate is preferred.

[0041] The concentration of metal ions in the plating solution according to this embodiment is not particularly limited, but may be, for example, about 10 to 80 g / L, and preferably about 35 to 75 g / L. In the case of copper sulfate pentahydrate, the preferred concentration is, for example, 50 to 300 g / L, and more preferably 100 to 280 g / L.

[0042] <2-2. Plating solution additives> The plating solution of this embodiment contains the plating solution additive of the previous embodiment in addition to the metal ions. In other words, it contains the nitrogen-containing sulfone compound. In the plating solution of this embodiment, multiple types of nitrogen-containing sulfone compounds may be used in combination, and other types of plating solution additives, such as a leveler, may also be used in combination.

[0043] (Content of nitrogen-containing sulfone compounds) In the plating solution of this embodiment, there is no particular limitation on the content of the compound having a nitrogen-containing sulfonyl structure represented by Formula 1, and it can be set as desired depending on the object to be plated and the metal salt used. For example, by adding the nitrogen-containing sulfone compound at a concentration of about 0.5 mg / L to 1000 mg / L, the filling properties can be further improved, with a concentration of about 1.0 to 500 mg / L being more preferable, and a concentration of about 10 to 200 mg / L being particularly preferable.

[0044] <2-3. Other additives> The plating solution of this embodiment may contain other additives in addition to the nitrogen-containing sulfone compound and metal ions. For example, the plating solution may contain additives such as a leveler having a different chemical structure from the nitrogen-containing sulfone compound, a brightener, a suppressor, an acid, a halide ion, a complexing agent, an antioxidant, a conductive salt, a wetting agent, or a dye such as a phthalocyanine compound. Some of these additives will be described below, but the additives are not limited to these.

[0045] (brightener) Brighteners not only impart brightness to the plated film, but also promote deposition of metal in recesses and can contribute to flattening the plated surface.

[0046] The type of brightener is not particularly limited, and examples include, but are not limited to, various aldehydes, benzothiazoles, sulfonic acids, sulfides, and other sulfur-containing compounds. Multiple types of brighteners can also be used in combination.

[0047] Among these, it is preferable to contain a brightener containing a sulfur-containing compound. A plating solution containing a sulfur-containing compound as a brightener can exhibit better planarization performance. Preferred sulfur-containing compounds include, but are not limited to, bis(3-sulfopropyl)disulfide (SPS), bis(2-sulfopropyl)disulfide, 3-mercapto-1-propanesulfonic acid, 3-(benzothiazol-2-ylthio)propane-1-sulfonic acid, 3-[N,N-dimethyl(thiocarbamoyl)thio]-1-propanesulfonic acid, 3-[(aminoiminomethyl)thio]-1-propanesulfonic acid, and salts thereof.

[0048] The concentration of the brightener is not particularly limited and can be, for example, about 0.01 to 10 mg / L. In particular, a concentration of about 0.1 mg / L to 5 mg / L is preferable. This can impart better brightness and smoothness to the metal plating film.

[0049] (inhibitor) Suppressors can also contribute to the leveling performance of the plating solution.

[0050] The inhibitor is not particularly limited, and for example, a polymer component, specifically, a polymer having various structures such as linear, branched, cyclic, network, etc. It is also possible to use a plurality of inhibitors in combination.

[0051] The plating solution preferably contains a suppressor containing a nonionic surfactant. By including such a suppressor, particularly a polymer component, the smoothing performance of the plating solution can be further improved.

[0052] Examples of nonionic surfactants include, but are not limited to, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, Pluronic (trademark) type surfactants, Tetronic type surfactants, polyethylene glycol glyceryl ether, and polyethylene glycol dialkyl ether.

[0053] There are no particular restrictions on the molecular weight of the inhibitor, but it is preferable that the weight average molecular weight is in the range of 100 to 50000, particularly 200 to 20000. With an inhibitor of such a molecular weight, better filling properties can be obtained.

[0054] There is no particular limitation on the concentration of the inhibitor, and it can be, for example, about 0.1 to 5000 mg / L, particularly about 0.1 to 2000 mg / L.

[0055] (surfactant) The plating solution may also contain a surfactant other than the suppressor. The surfactant can be selected from among ordinary anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, etc. When a surfactant is contained, its concentration is preferably about 10 mg / L to 50 g / L, and more preferably about 50 mg / L to 500 mg / L.

[0056] (acid) The plating solution may contain an acid. There are no particular limitations on the acid used, and any known inorganic and / or organic acid, such as sulfuric acid or nitric acid, may be used depending on the composition of the plating solution and the object to be plated. For example, when the water-soluble metal salt is copper sulfate, the plating solution preferably contains sulfuric acid as the acid.

[0057] There is no limitation on the concentration of the acid, and it can be, for example, about 5 to 300 g / L, particularly about 10 to 250 g / L.

[0058] (halide ions) The plating solution may contain halide ions such as chlorine, bromine, and iodine. The halide ions include, in particular, chloride ions (Cl - ) is preferred. Halide ions can improve the brightness and leveling performance of the plating solution.

[0059] The concentration of halide ions can be, for example, 0.01 to 200 mg / L, preferably about 10 to 100 mg / L, in terms of ion mass concentration in the plating solution.

[0060] (complexing agent) Complexing agents are additives that can contribute to stabilizing metal ions in plating solutions and homogenizing the composition of deposited alloys in alloy plating. Plating solutions containing precious metals, such as silver, typically use complexing agents such as oxycarboxylic acids, polycarboxylic acids, and monocarboxylic acids. When a complexing agent is included, its concentration can be, for example, about 0.1 g / L to 500 g / L, and particularly about 1 g / L to 100 g / L.

[0061] Specific examples of complexing agents include gluconic acid, citric acid, glucoheptonic acid, gluconolactone, glucoheptolactone, formic acid, acetic acid, propionic acid, butyric acid, ascorbic acid, oxalic acid, malonic acid, succinic acid, glycolic acid, malic acid, tartaric acid, diglycolic acid, thioglycolic acid, thiodiglycolic acid, thioglycol, thiodiglycol, mercaptosuccinic acid, 3,6-dithia-1,8-octanediol, 3,6,9-trithiadecane-1,11-disulfonic acid, and thiobis(dodecaethylene glycol). , di(6-methylbenzothiazolyl)disulfide trisulfonic acid, di(6-chlorobenzothiazolyl)disulfide disulfonic acid, gluconic acid, citric acid, glucoheptonic acid, gluconolactone, glucoheptolactone, dithiodianiline, dipyridyl disulfide, mercaptosuccinic acid, sulfite, thiosulfate, ethylenediamine, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), nitrilotriacetic acid (NTA), iminodiacetic acid (IDA), iminodipropionic acid (IDP), hydroxyethylethylenediaminetriacetic acid (HEDTA), triethylenetetraminehexaacetic acid (TTHA), ethylenedioxybis(ethylamine)-N,N,N',N'-tetraacetic acid, glycines, nitrilotrimethylphosphonic acid, and salts thereof. Furthermore, sulfur-containing compounds such as thioureas, tris(3-hydroxypropyl)phosphine, and the like may also be contained.

[0062] (antioxidant) Antioxidants are used to prevent oxidation of metal salts and are important in tin plating solutions, etc. The antioxidant can be contained at a concentration of, for example, about 0.1 g / L to 500 g / L, particularly about 1 g / L to 100 g / L. Examples of antioxidants include hypophosphorous acids, ascorbic acid, phenolsulfonic acid, cresolsulfonic acid, hydroquinonesulfonic acid, hydroquinone, α- or β-naphthol, catechol, resorcinol, phloroglucinol, hydrazine, phenolsulfonic acid, catecholsulfonic acid, hydroxybenzenesulfonic acid, naphtholsulfonic acid, and salts thereof.

[0063] <2-4. Preparation of plating solution> The plating solution of this embodiment can be prepared from the above-mentioned components using a conventional method, and the details may be appropriately determined taking into consideration the composition and blending amounts of each component.

[0064] ≪3. Manufacturing method of electronic substrate≫ As described above, by performing plating treatment using the plating solution of the previous embodiment, filling, for example, via filling, of printed wiring boards, semiconductor wafers, etc. This embodiment is a method for manufacturing an electronic substrate, which includes a step of plating a substrate using the above plating solution.

[0065] <3-1. Plating target> The manufacturing method of this embodiment can be applied to various substrates, wafers, etc. The manufacturing method of this embodiment has excellent filling characteristics and is also capable of forming a flat plated surface. Furthermore, it has excellent electrodeposition uniformity and can flatten voids of various sizes ranging from sub-micron to hundreds of microns. The plating solution of the previous embodiment also has excellent anisotropy and can plate only the target area, making it useful for plating electronic components, etc. Examples of electronic components include glass substrates, silicon substrates, wafers, printed circuit boards, flexible printed circuit boards, film carriers, semiconductor integrated circuits, resistors, capacitors, filters, inductors, thermistors, quartz oscillators, switches, lead wires, etc., but the processing targets are not limited to these. The plating solution of the previous embodiment can also be applied to a portion of an electronic component, such as a bump electrode on a wafer, to form a film.

[0066] There are no particular limitations on the material of the substrate to be plated. For example, substrates that can be plated include those in which a conductive layer of metal or the like is formed and patterned on a substrate made of resin or the like, semiconductor substrates such as silicon wafers, electronic circuit substrates such as printed circuit boards, and glass substrates, each of which has a fine circuit pattern on its surface.

[0067] These substrates may contain a mixture of blind via holes, trenches for fine wiring, through-holes that penetrate the substrate, etc. The manufacturing method of this embodiment has excellent filling characteristics, making it suitable for plating substrates with vias or trenches. The manufacturing method of this embodiment can also be used for forming wiring on a substrate.

[0068] Specific examples of these substrates include printed circuit boards such as package substrates on which IC bare chips are directly mounted, silicon wafers on which LSIs and the like are directly mounted, and silicon wafer substrates intended for the manufacture of semiconductor chips themselves.

[0069] <3-2. Plating treatment> The manufacturing method of this embodiment can be carried out by, for example, subjecting the substrate as described above to a normal plating process. An example of the plating process in the manufacturing method of this embodiment will be described below.

[0070] For example, a substrate to be plated is subjected to pretreatment such as the formation of a barrier layer, if desired, and then subjected to a conductive treatment such as the formation of a metal seed layer to serve as a power supply layer on the substrate. This conductive treatment can be carried out by a conventional conductive treatment method, such as a metal (including carbon) coating treatment by electroless plating, a so-called direct plating method using carbon, palladium, or the like, sputtering, vapor deposition, or chemical vapor deposition (CVD), etc.

[0071] The substrate that has been subjected to the conductive treatment is then plated with the plating solution of the previous embodiment. The conditions for this are not particularly limited, and may be the same as ordinary plating conditions. For example, the solution temperature is about 20 to 40°C, and the cathode current density is 0.05 to 10 A / dm 2 The plating may be performed at a current of about 1000 W / m, and the current used for plating may be either a direct current or a pulsed current. The plating time may be appropriately set depending on the purpose of plating. Furthermore, during plating, it is preferable to agitate the solution by aeration, pump circulation, paddle stirring, etc.

[0072] According to the embodiment described above, blind via holes, through holes, trenches, silicon through electrodes, glass through electrodes, etc. in the electronic substrate can be filled with a thin surface plating thickness (the plating thickness of the substrate parts that are plated simultaneously with the blind via holes, through holes, trenches, silicon through electrodes, and glass through electrodes and do not have these).

[0073] Specifically, for example, in order to completely fill a patterned substrate having a blind via hole with a diameter of 65 μm and a depth of 40 μm by plating, a current of 2.0 A / dm 2The plating can be performed for about 30 minutes at a cathode current density of 1000 .mu.m. In this case, the thickness of the surface plating layer can be, for example, about 15 .mu.m.

[0074] For the purpose of semiconductor manufacturing, for example, in order to completely fill via holes or trenches with a diameter of 0.1 to 0.5 μm and a depth of 0.2 to 1 μm by plating a substrate such as a silicon wafer, a current of 2 A / dm 2 It is also possible to plate for about 150 seconds at a cathode current density of about 1000 volts. In this case, the surface plating thickness will be about 1 μm.

[0075] Furthermore, for the purpose of three-dimensional packaging, for example, to fill a silicon through-hole with plating having a diameter of 10 μm and a depth of 50 μm, a current of 0.2 A / dm 2 The plating thickness at this time is, for example, about 2 μm. For example, for filling plating on a silicon through-hole electrode with a diameter of 20 μm and a depth of 100 μm, a cathode current density of 0.2 A / dm 2 It is also possible to plate for about 60 minutes at a cathode current density of 1000 kJ / cm. In this case, the surface plating thickness will be, for example, about 4 μm.

[0076] The processing operations and conditions in the manufacturing method of this embodiment are not limited to those described above, and the manufacturing method of this embodiment can be applied to various plating processes or devices. [Example]

[0077] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these descriptions in any way.

[0078] <Synthesis Examples 1-25> Various nitrogen-containing sulfone compounds constituting the plating solution additive according to the present invention were synthesized as follows. In the following synthesis examples, the structure of the product is 1The weight average molecular weight (Mw) was analyzed by H-NMR etc. and GPC. GPC analysis was performed using a refractive index detector (RI) with monodisperse polyethylene oxide and polyethylene glycol as standard samples. NMR measurement was performed at 400 MHz.

[0079] <Synthesis Example 1> 11.0 g of pure water and 0.83 g of N,N'-trimethylenebis[2-(vinylsulfonyl)acetamide] (VS-C manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.: structural formula below) were added to a reaction vessel and heated to 50°C. Next, 0.44 g of 1,2-bis(2-aminoethoxy)ethane was added little by little and reacted for 3 hours. After returning to room temperature, 1.0 g of 50% sulfuric acid and pure water were added to obtain the nitrogen-containing sulfone compound-1 having the above-mentioned NS structure-1 in the form of an 8.5 wt% aqueous solution. The progress of the reaction was 1 This was confirmed by 1 H-NMR, which showed the disappearance of signals around 6.5 ppm and 7.0 ppm. [ka]

[0080] <Synthesis Examples 2 to 25> The same operations as in Synthesis Example 1 were carried out, except that the compounds listed in Table 1 were used as raw materials. The nitrogen-containing sulfonyl structures (indicated by the numbers of the specific examples of the NS-containing structure listed above) and weight-average molecular weights (Mw) of the raw materials used and the products are shown in Table 1, along with the data for Synthesis Example 1. Note that VS-B used in Synthesis Example 5 and the like is N,N'-ethylenebis[2-(vinylsulfonyl)acetamide] manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., and has the following structure. [ka]

[0081] [Table 1]

[0082] Examples 1 to 25 (Preparation of copper sulfate plating solution) Using nitrogen-containing sulfone compounds 1 to 25 obtained in Synthesis Examples 1 to 25, copper sulfate plating solutions having the following compositions according to the present invention were prepared. <Copper sulfate plating solution composition> ·Copper sulfate pentahydrate: 200g / L(Cu 2+ Concentration: 50g / L) ·Sulfuric acid: 50g / L Chloride ions: 40 mg / L (Cl - concentration, added as hydrochloric acid) Polyethylene glycol (molecular weight 6000) (surfactant): 500 mg / L Bis-(3-sodium sulfopropyl) disulfide (brightener): 1 mg / L Nitrogen-containing sulfone compounds 1 to 25: Concentrations are listed in Table 2 below.

[0083] (copper sulfate plating) A resin substrate having an electroless copper-plated blind via hole with an opening diameter of φ65 μm and a depth of 40 μm was placed in each of the above copper sulfate plating solutions, and copper sulfate plating was carried out under the following conditions. <Copper sulfate plating conditions> ·Current density: 2.0A / dm 2 Duration: 34 minutes ·Bath temperature: 25℃ ·Bath volume: 500mL Agitation: Aeration 2.0L / min

[0084] (Evaluation of filling ability) For each plated substrate, the depth of the depressions (indentations) (μm) was measured using a three-dimensional white light interference microscope, and those with an indentation (indentation) depth of less than 1 μm were evaluated as ⊚, those with an indentation depth of 1 μm or more but less than 5 μm as ◯, and those with an indentation depth of 5 μm or more as ×. The evaluation results are shown in Table 2 below.

[0085] <Comparative Examples 1 to 3> The filling property was evaluated by the same procedures as in Examples 1 to 25, except that the following compounds or general-purpose levelers were used instead of the nitrogen-containing sulfone compounds. The evaluation results are shown in Table 2 below, along with the results of the examples. Comparative Example 1: KA-1375 (compound represented by the following formula, weight average molecular weight 5923) Comparative Example 2: PAA-D41-HCl (compound represented by the following formula, weight average molecular weight 20,000, manufactured by Nitto Boseki Co., Ltd.) Comparative Example 3: PAS2401 (compound represented by the following formula, weight average molecular weight 2000, manufactured by Nitto Boseki Co., Ltd.) [ka]

[0086] [Table 2]

[0087] As is clear from the results shown in Table 2, the plating solutions of Examples 1 to 25, which contained the plating solution additives of Synthesis Examples 1 to 25, each of which was composed of a compound having a nitrogen-containing sulfonyl structure represented by Formula 1 according to the present invention, all exhibited excellent filling properties.

[0088] On the other hand, the plating solutions of Comparative Examples 1 and 2, which used a compound not containing a sulfonyl group as a leveler, did not exhibit good filling properties. In Comparative Example 3, a compound having both a sulfonyl group and a nitrogen-containing ring was used, but the evaluation results for filling properties were poor. This demonstrates the importance of the sulfonyl compound having a nitrogen-containing functional group in the same main chain as the sulfonyl group, as in the present invention.

Claims

1. The present invention relates to a compound having a nitrogen-containing sulfonyl structure represented by the following formula 1: Additive for plating solution. 【Chemistry 1】 (In Formula 1, X is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, a substituted or unsubstituted xylylenediyl group, or a group represented by Formula 2 or Formula 3, which may have any of a linear, branched, or cyclic structure; Y is a substituted or unsubstituted (poly)alkyleneoxy group, a substituted or unsubstituted (poly)alkyleneimino group, a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted xylylenediyl group, which may have any of a linear, branched, or cyclic structure; R １ is an alkylene group; a+b R ２ may be the same or different and are a hydrogen atom or an alkyl group; a and b are each independently 1 or 2. 【Chemistry 2】 (In Formula 2 and Formula 3, R ３ represents a substituted or unsubstituted alkylene group, a substituted or unsubstituted arylene group, a substituted or unsubstituted aralkylene group, or a substituted or unsubstituted xylylenediyl group, which may have a linear, branched, or cyclic structure; R ３ When there are a plurality of R , they may be the same or different; Z is a substituted or unsubstituted (poly)alkyleneoxy group, which may have any of a linear, branched, or cyclic structure; ４ may be the same or different and are a hydrogen atom or an alkyl group; c and d are each independently 1 or 2.

2. The compound has a nitrogen-containing sulfonyl structure represented by the following formula 4: The plating solution additive according to claim 1 . 【Transformation 3】 (In formula 4, X, Y, R １ , R ２ a and b are the same as those in Formula 1 above; e is 1 or 2 independently of a and b; １ and R ２ may be the same or different.)

3. The compound has a structure in which the nitrogen-containing sulfonyl structure is bridged via the group in X and / or Y in Formula 1. The plating solution additive according to claim 1 or 2.

4. In the compound, X in the formula 1 is an ethylene group, a (poly)ethyleneoxy group, a (poly)propyleneoxy group, or —CH ２ -C(=O)-NH(CH ２ ) ２ NH-C(=O)-CH ２ - group, -CH ２ -C(=O)-NH(CH ２ ) ３ NH-C(=O)-CH ２ - group, -N ＋ (CH ３ ) ２ -Za-N ＋ (CH ３ ) ２ - group (Za is a (poly)alkyleneoxy group substituted with a hydroxy group), and a propylene group substituted with a hydroxy group; The plating solution additive according to claim 1 or 2.

5. In the compound, Y in formula 1 is a (poly)alkyleneoxy group. The plating solution additive according to claim 1 or 2.

6. the compound further has a hydroxy group-containing (poly)alkyleneoxy group, a glycidyl group, a halogenated hydrocarbon group, and / or a sulfonate ester group; The plating solution additive according to claim 1 or 2.

7. The weight average molecular weight (Mw) of the compound is 300 or more and 50,000 or less. The plating solution additive according to claim 1 or 2.

8. metal ions, and The plating solution additive according to claim 1 or 2 is contained. Plating solution.

9. the metal ions include copper ions; The plating solution according to claim 8.

10. The plating solution additive contains the compound constituting the plating solution additive at a concentration of 0.5 mg / L to 1000 mg / L. The plating solution according to claim 8.

11. A step of plating a substrate using the plating solution according to claim 8. Manufacturing method for electronic substrates.

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