TWI534304B - Copper electrolytic plating bath and copper electrolytic plating method - Google Patents

Description

Copper electroplating bath and copper electroplating

The invention relates to a copper electrolytic plating bath and a copper electrolytic plating method, which enable high-speed plating of objects to be plated, in particular articles having perforations, blind via holes or pillars.

In the case of copper electrolytic plating on a flat surface such as a laminated copper foil on a substrate, high-speed plating is currently performed by increasing the plating bath temperature and the cathode current density (see Japanese Patent No. 3758552). However, in the case of copper electrolytic plating on a substrate having perforated (TH) or blind via holes (through holes), due to the ability to thicken the plating (TP: the ability of the electrolytic solution to deposit metal in a uniform thickness) and the physical properties of the deposit Due to the requirements of properties (such as appearance, tensile strength, elongation, etc.), it is not easy to accelerate plating.

When the substrate has a small aspect ratio (AR) of perforations or blind via holes, high speed plating may be achieved by enhancing plating agitation and increasing the plating temperature. However, if the aspect ratio becomes large, there arises a problem that the plating thinning ability deteriorates together with the physical properties of the deposit. Therefore, there is a limit to the type of substrate to be plated which is subjected to high-speed plating by enhancing agitation and increasing the plating temperature.

In the conventional copper electrolytic plating bath, if the plating temperature is lower than 30 ° C and the cathode current density is less than 5 A/dm ² , the plating has been performed by increasing the agitation while ensuring the plating uniformity and the physical properties of the deposit within an allowable range. . However, by applying other accelerations of at least 5 A/dm ² , the plating temperature must be raised due to limitations in starting agitation. Elevated temperatures have shown the problem of electroplating conventional organic additives with perforated and blind via holes that lose their efficacy.

In the case of column plating which is plated by the recessed portion formed by the protective agent film, if the protective agent film has individual openings of a low height and a large size (i.e., a small aspect ratio), such as a blind via hole, As long as the agitation is enhanced, an electrolytic plating bath can be used to ensure the plating uniformity and the physical properties of the deposit. However, if the aspect ratio becomes large, it is expected that there will be no good plating even if strong agitation is performed. Even if plating is performed at a high speed by enhancing the agitation and increasing the plating temperature, there is still a problem that the deposit cannot be flattened. In any case, when plating on a column (bump) having a large aspect ratio at a high speed, the plating temperature must be increased. Among the plating on a substrate having perforated or blind via holes and plating on a pillar (bump), an additive suitable for high temperature plating has been required.

The present invention has been accomplished under the circumstances of the present technology, and an object of the present invention is to provide high-speed plating on a substrate on which perforations, blind via holes, pillars, and the like are formed while maintaining good plating uniformity and ensuring physical properties of deposits. Copper electrolytic plating bath.

Another object of the present invention is to provide a copper electrolytic plating bath containing an organic additive which is effective in promoting high temperature electroplating.

Another object of the present invention is to provide a copper electrolytic plating method using the above copper electrolytic plating bath.

The advantages of high speed plating include the possibility of shortening the plating time and increasing the number of outputs per unit time. If the production time can be shortened, the output will increase. In addition, in terms of the same amount of output, the space of the plating apparatus can be saved and the size of the plating apparatus can be made smaller (for example, the number of piping and plating equipment can be reduced). For example, if the cathode current density can be doubled, any of the length of the line, the number of plating baths, the number of plating baths, and the plating time can be substantially reduced by half. Therefore, the acceleration of electroplating is important from the viewpoint of reducing the electroplating cost.

First, the inventors assumed in the following manner that the substrate having perforations, blind via holes, and the like has not been subjected to high-speed plating in the past (i.e., due to the problem of high-speed plating).

(1) The plating thickness of the perforated or blind via hole is deteriorated, so it does not meet the requirements of high-speed plating. The column geometry is poorly altered and therefore does not meet this requirement.

(2) The physical properties of the sediment deteriorate. Especially the gloss is not satisfactory.

(3) When a soluble anode is used, the anode is converted to non-conducting. When the current density is increased at 25 ° C, the copper concentration near the anode becomes high. In this case, the crystal of copper sulfate pentahydrate tends to deposit on the anode, thereby making the anode non-conductive.

(4) There are no organic additives, especially a homogenizer which can be used at high temperatures.

On the other hand, if the plating temperature becomes high, the solubility of copper sulfate pentahydrate is improved, so that crystallization cannot occur, and there is a concomitant advantage that non-conductivity cannot occur.

As a compound suitable as a homogenizer for a high-speed copper electrolytic plating bath, a study has been conducted to obtain a compound (i) as an effective additive, and the compound (i) can maintain the effect as a homogenizer when strongly stirred and the plating temperature is raised. That is, a compound which exhibits high plating uniformity for perforation and blind via holes and which can form a plating film having good physical properties, or a compound which can be plated by a flat column (bump).

Further, if the effect of any of the accelerator or the inhibitor of the organic additive is too large under the elevated temperature condition, the physical properties of the deposit deteriorate, and the plating thickening ability is lowered. In order to avoid this, the inventors have conducted research to obtain a compound which can balance the effect of the promoter and the inhibitor of the organic additive contained in the plating bath under the conditions of increasing the plating temperature as an effective additive.

The present inventors have conducted thorough research to solve the above problems, and as a result, found to have perforation in the presence of copper sulfate, sulfuric acid, and chloride ions, and as an organic additive, a sulfur atom-containing organic compound and a nitrogen atom-containing organic compound, which are adjusted to supply electroplating. In a copper electrolytic plating bath of a substrate such as a blind via hole or a column, when a specific polymer compound is used as the nitrogen atom-containing organic compound, high-speed copper electrolytic plating can be satisfactorily performed. More specifically, the polymer compound as a nitrogen atom-containing organic compound is made by including it in an acidic aqueous solution. The porphyrin reacts with the epichlorohydrin of the dimoral to obtain the reaction product, and one to two moles (relative to one mole) The imidazole of the porphyrin is obtained by a two-stage reaction in which the reaction product is further reacted. The polymer compound effectively functions as a homogenizer, particularly in a copper electrolytic plating bath at temperatures up to 35 ° C or higher. As a result, high-speed copper electrolytic plating can be performed on a substrate on which perforations, blind via holes, pillars, and the like are formed, while maintaining the plating uniformity and ensuring the physical properties of the deposit.

Accordingly, the present invention provides the following copper electrolytic plating bath and copper electrolytic plating method.

[1] A copper electrolytic plating bath comprising copper sulfate (as copper sulfate pentahydrate) in an amount of 50 to 250 g/l, sulfuric acid in an amount of 20 to 200 g/l, and chlorine in an amount of 20 to 150 mg/l An ion, and a sulfur atom-containing organic compound and a nitrogen atom-containing organic compound as an organic additive, the nitrogen atom-containing organic compound being a nitrogen atom-containing polymer compound, which is obtained by including in an acidic aqueous solution. The porphyrin reacts with the epichlorohydrin of the dimoral to obtain the reaction product, and one to two moles (relative to one mole) The imidazole of the porphyrin is obtained by a two-stage reaction in which the reaction product is further reacted.

[2] The copper electrolytic plating bath according to [1], wherein the nitrogen atom-containing polymer compound is present in an amount of from 1 to 1000 mg/l.

[3] The copper electrolytic plating bath according to [1], wherein the sulfur atom-containing organic compound is selected from the group consisting of sulfur atom-containing organic compounds represented by the following formulas (1) to (4), and is present in an amount of from 0.001 to 100 mg/ l

H─S─(CH ₂ ) _a ─(O) _b ─SO ₃ M (1)

Wherein R ₁ , R ₂ and R ₃ independently represent an alkyl group having 1 to 5 carbon atoms, M represents a hydrogen atom or an alkali metal, a is an integer of 1 to 8, and b, c and d are each 0 or 1.

[4] A copper electrolytic plating method comprising electroplating an object to be electroplated at a temperature of 30 to 50 ° C in a copper electrolytic plating bath of any one of [1] to [3].

[5] The copper electroplating method according to [4], wherein the object to be electroplated is a substrate having perforations, blind via holes or pillars.

[6] The copper electroplating method according to [5], wherein the perforation has a diameter of 0.05 to 2.0 mm, a height of 0.01 to 2.0 mm, and an aspect ratio of 0.1 to 10, and the blind via hole has a diameter of 20 to 300 μm. The height is 20 to 150 μm, and the column has a diameter of 30 to 300 μm, a height of 25 to 200 μm, and an aspect ratio of 0.2 to 3.

Advantageous effects of the present invention

The nitrogen atom-containing polymer compound as an organic additive and acting as a homogenizing agent has an unmodified quality at an elevated plating temperature and can maintain an accelerator effect and an inhibitor effect caused by an organic additive in an electroplating bath under temperature increase conditions. A good balance between. Therefore, the copper electrolytic plating bath of the present invention has the ability to plate the perforation or blind via holes and to maintain the physical properties of the deposit when the plating temperature is raised. With the copper electrolytic plating bath of the present invention, high speed plating can be performed even under weak agitation such as air agitation than the jet stream. In the past, high speed plating has hitherto been carried out by applying plating temperature and cathode current density conditions which substantially require vigorous agitation such as jet flow.

The invention will now be described in more detail.

The copper electrolytic plating bath of the present invention contains copper sulfate, sulfuric acid and chloride ions. The amount of copper sulfate contained is 50 to 250 g/l, preferably 100 to 200 g/l, based on copper sulfate pentahydrate, and the amount of sulfuric acid contained is 20 to 200 g/l, preferably 50 to 200. The g/l, and the amount of chloride ions contained therein is from 20 to 150 mg/l, preferably from 30 to 100 mg/l.

The copper electrolytic plating bath of the present invention additionally contains an organic compound containing a sulfur atom and an organic compound containing a nitrogen atom. The sulfur atom-containing organic compound may be a sulfur atom-containing organic compound which is conventionally used for copper electrolysis plating of perforated or blind via holes. More specifically, the sulfur atom-containing organic compound of the following formulas (1) to (4) can be used:

H─S─(CH ₂ ) _a ─(O) _b ─SO ₃ M (1)

Wherein R ₁ , R ₂ and R ₃ independently represent an alkyl group having 1 to 5 carbon atoms, M represents a hydrogen atom or an alkali metal, a is an integer of 1 to 8, and b, c and d are each 0 or 1. The concentration of the compound in the copper electrolytic plating bath is usually from 0.001 to 100 mg/l.

The nitrogen atom-containing organic compound used in the copper electroplating bath of the present invention is a polymer compound which is made into a molar by including in an acidic aqueous solution. The porphyrin reacts with the epichlorohydrin of the dimoral to obtain the reaction product, and one to two moles (relative to one mole) The imidazole of the porphyrin is obtained by a two-stage reaction in which the reaction product is further reacted. The nitrogen-containing polymer compound acts as a so-called homogenizer, and does not undergo a quality change when the plating temperature is raised (for example, to 30 ° C or higher, particularly to 35 to 50 ° C). The polymer compound maintains a good balance between the accelerator effect and the inhibitor effect caused by the organic additive contained in the plating bath under high temperature conditions. The nitrogen-containing portion is formed on a non-flat portion (such as a perforation or a blind via hole) formed on the substrate, or in the process of forming a pillar (bump) on a copper electroplating such as a non-flat portion formed by a resist film. The polymer compound acts as an effective homogenizer to maintain the ability to plate thickness and the physical properties of the deposit, as the plating temperature increases.

The nitrogen atom-containing polymer compound is conventionally known as CAS 109882-76-0 and is considered to be a polymer compound having a polyether structure. The polymer compound is comprised of a molar The first stage reaction between the porphyrin and the dimorinol epichlorohydrin and the first to second morrel (preferably about two moles, more preferably 1.8 to two moles) of imidazole added to the first stage of the reaction product The two-stage reaction of the two-stage reaction is obtained by providing a polymer compound.

More specifically, for example, a moir The porphyrin was dissolved in about 375 ml of distilled water and adjusted to pH 5.5 by HCl. Dimorol epichlorohydrin was dropped into the solution at a reaction temperature of about 50 ° C, and then maintained at 40 to 50 ° C until no free epichlorohydrin was detected (first stage). Next, a mole of imidazole was added to the reaction product obtained in the first stage, and 50 g of NaOH dissolved in 125 ml of water was added thereto, followed by a reaction at 55 ° C to 60 ° C for 6 hours (second stage). Further, water is added to the obtained solution, whereby a total amount of the formed solution of 1 liter can be used. Ralu (registered trademark) Plate MOME (manufactured by Raschig GmbH) or the like can be proposed as a commercially available product of such a polymer compound.

The concentration of the nitrogen atom-containing polymer compound in the copper electrolytic plating bath is from 1 to 1,000 mg/l, preferably from 10 to 500 mg/l.

The copper electrolytic plating bath of the present invention may additionally comprise an oxygen-containing organic compound comprising a polyether organic additive such as polyethylene glycol for copper electrolytic plating of perforated or blind via holes. The concentration of the oxygen-containing organic compound in the copper electrolytic plating bath is preferably from 0.001 to 5,000 mg/l. It should be noted that the polyethylene glycol which can be used in the present invention has a molecular weight of from 200 to 200,000. The molecular weight of this example was measured according to the method described in Japanese Pharmacopoeia.

In the copper electrolytic plating using the copper electrolytic plating bath of the present invention, conventional plating conditions can be applied. In particular, when a plating temperature of not lower than 35 ° C (preferably 35 ° C to 50 ° C) and a cathode current density of not less than 5 A/dm ² (preferably 5 to 20 A/dm ² ) are used, It is possible to obtain a more stable plating thickness and better sediment characteristics than those obtained in conventional copper electrolytic plating.

The anode used is preferably an insoluble anode. For example, an anode coated with platinum, ruthenium oxide or the like on titanium may be used. Various types of agitation that can be used by conventional agitation tools include, for example, jet agitation or cyclic agitation by a pump, or air agitation by an air pump, and machinery produced by paddles, cathode locking tools, and the like. agitation.

Copper electrolytic plating using the copper electrolytic plating bath of the present invention is particularly suitable for a non-flat portion formed of a resist film on a substrate or in which a non-flat portion (such as a perforation or a blind via hole) is formed or formed in a pillar (bump) or the like. Copper electrolytic plating of an electroplated article such as a printed circuit board. Copper electrolytic plating is particularly effective in the case where deposits are formed on the inner surface of the blind via hole (including the bottom surface and the side surface of the blind via hole) (the case where the via hole is filled with the via hole filled by the copper plating) is particularly effective.

The present invention is suitable for copper electroplating of substrates having large aspect ratio (AR) perforations or blind via holes. For example, the present invention has a diameter of 0.05 to 2.0 mm, preferably 0.1 to 1.0 mm, a sheet thickness (height) of 0.01 to 2.0 mm, preferably 0.05 to 1.6 mm, and an aspect ratio (AR, i.e., height/diameter). a perforation of 0.1 to 10, preferably 0.1 to 5.0, and a diameter of 20 to 300 um μm, preferably 30 to 200 μm, and a height (depth) of 20 to 150 μm, preferably 40 to 100 μm, High-speed plating of blind via holes having an aspect ratio (AR, i.e., height/diameter) of 0.2 to 1.5, preferably 0.4 to 1.0 is effective.

When a pillar (bump) is formed by electroplating, the following two methods are mainly used: an electroplated copper layer is formed on the surface of the object to be formed into the pillar (bump) and the pillar (bump) forming portion is protected with a protective agent film, and then Etching a portion not covered by the protective film and then removing the protective film; and forming a plating protectant pattern by a protective agent film on the surface of the object to open a column (bump) to be formed and in the opening portion A method of performing copper plating followed by removing the protective agent film. In the former method, copper plating may be accelerated. However, when a column (bump) having a large aspect ratio (AR) is formed, the periphery of the formed column (bump) is severely eroded into a bobbin shape along the central portion of its height, and the accompanying problem is local verticality. reduce. When the formed pillar (bump) is high, there is a problem that etching takes a long time.

When a column (bump) is formed by copper electrolytic plating according to the present invention, it is preferred to use a method using a plating resist film. More particularly, the copper electroplating of the present invention is for a column (bump) of a large aspect ratio (AR), for example, having a diameter of 30 to 300 μm, preferably 50 to 200 μm, and a height (protective film height) of 25 to High-speed plating of 200 μm, preferably 30 to 150 μm, and an aspect ratio (AR) of 0.2 to 3, preferably 0.3 to 2 (bulge) is effective. In this case, it will be noted that the plating causes the deposit to fill the recessed portion of the plating protectant opening.

Example

The examples and comparative examples are shown to more clearly illustrate the invention, and the invention should not be construed as being limited by the following examples.

Examples 1 to 4 and Comparative Examples 1 to 3

Using a laminate substrate having perforations (four types) or blind via holes (both types) as shown in Table 2, a copper electrolytic plating bath using the following formulation was formed in the perforated or blind via holes under the following plating conditions. Electrolytic plating of copper layers. It should be noted that copper electrolytic plating is carried out in a manner of performing a known pretreatment on a portion where a copper deposit is to be formed, on which an electroless copper film (thickness: 0.3 μm) is formed as a lower layer, followed by copper electrolytic plating.

<Copper Electroplating Bath>

Copper sulfate pentahydrate: 150 g/l

Sulfuric acid: 150 g/l

Chloride ion: 50 mg/l

Organic additives: shown in Table 1

<plating conditions>

Cathode current density: 15 ASD (A/dm ² )

Temperature: 40 ° C

Plating time: 8 minutes (corresponding to copper layer thickness of 26 μm)

Stirring: slightly stronger air agitation

SPS: disodium bis(3-sulfopropyl)disulfide disodium

PEG #6000: polyethylene glycol 6000 (manufactured by Wako Pure Chemical Industries, Ltd.)

Polymer Compound 1: Ralu (trademark) Plate MOME (manufactured by Raschig GmbH)

PAS-A-5: a copolymer of diallyldialkylammonium and sulfur dioxide (manufactured by Nitto Boseki Co., Ltd. and having an average molecular weight of 4,000)

JGB: Janus green black

It will be noted that the amounts of PAS-A-5 and JGB are respectively set to the additive concentration sufficient to provide gloss in the highest potential region when tested by Hertz.

The appearance after copper electrolytic plating was visually observed, and the plating thinning ability (TP) was evaluated in the following manner. The results are shown in Table 2.

[Evaluation of plating thickness (TP)]

(1) Perforation (TH)

The thickness of the copper layer at the portions A to F shown in Fig. 1(A) was measured, and then evaluated by the ratio (%) calculated according to the following equation. It should be noted that with respect to E and F, the thicknesses of the central portions of the perforations represented by Examples 1 to 4, Control Examples 1, 3, E ₁ and F ₁ were measured, and Comparative Example 2 was measured by E ₂ and F ₂ . The thickness of the upper end portion of the perforation.

TP (%) = 2 × (E + F) / (A + B + C + D) × 100

E = E ₁ or E ₂ and F = F ₁ or F ₂ .

(2) blind via hole

The thickness of the copper layer at the portions A to C shown in Fig. 1(B) was measured, and then evaluated by the ratio (%) calculated by the following equation.

TP (%) = 2 × C / (A + B) × 100

In Figs. 1(A) and 1(B), 1 is a substrate (insulating layer), 2 is laminated copper, 3 is an electroless copper layer, 4 is an electroplated copper layer, and t is a perforation, and v For blind via holes.

It will be noted that in Comparative Example 2, the thickness of the copper layer was the smallest at the corner portion of the open side of the blind via hole, and the thickness of the copper layer was the smallest at the corner portion of the bottom side except for this example.

<perforation>

Examples 1 to 4, Comparative Example 1: In the case where the thickness of the substrate is small (or the length of the perforation is short), current concentration is suppressed inside the perforation, so that the thickness of the copper layer inside the perforation is substantially the same as the surface, and thus the plating uniformity It is about 100%. When the thickness of the substrate is thick (or the length of the perforation is long), the current plating thickness reduction ability inside the perforation is small, so that the plating uniformity is suppressed from deteriorating.

Comparative Example 2: The homogenizer inhibited the deposition of the perforated corner portion to form a small thickness.

Comparative Example 3: When the thickness of the substrate was small (the length of the perforation was short), the current was concentrated on the perforated portion, so that the thickness of the copper layer inside the perforation was thick, so that the plating uniformity was much lower than 100%. On the other hand, when the thickness of the substrate is large (or the length of the perforation is long), the current does not flow through the inside of the perforation, so that the thickness of the copper layer in the central portion of the perforation becomes small, thereby deteriorating the plating uniformity.

<blind via hole>

Examples 1 to 4: The copper deposit on the surface was suppressed by a suitable uniform effect, and the current passed through the inside of the blind via hole. The suppression effect of the corner portion of the bottom side of the blind via hole is weak, so that the current also flows to the corner portion of the bottom side of the blind via hole.

Comparative Example 1: The uniformity effect was weak, and the plating portion of the bottom side of the blind via hole where the current could not flow was poor in plating uniformity.

Comparative Example 2: The uniform effect was too strong, so the uniform agent inhibited the deposition of the corner portion of the open side of the blind via hole to form a film.

Comparative Example 3: Due to the absence of a homogenizer, the plating thickness of the bottom side of the blind via hole where current cannot flow to is extremely poor.

The physical properties of the copper layer were evaluated using the copper electrolytic plating baths of Examples 1 to 4 and Comparative Examples 1 to 3 according to the following procedures.

[Evaluating the physical properties of the copper layer]

The SUS sheet was subjected to the following pretreatment, and an electroplated copper layer was formed on the SUS sheet under the following plating conditions using the above copper electrolytic plating bath. Further, after performing the following post-treatment, the foil-like plating layer was peeled off from the SUS sheet. The plating film (layer) was evaluated for tensile strength and elongation according to the following method.

<pretreatment>

(1) Acid detergent treatment (MSC-3-A, manufactured by Uyemura & Co., LTD.)

(2) hot water cleaning

(3) Water cleaning

(4) pickling

(5) Water cleaning

<plating conditions>

Cathode current density: 15 ASD (A/dm ² )

Temperature: 40 ° C

Plating time: 15 minutes (corresponding to the thickness of copper layer of 50 μm)

Stirring: slightly stronger air agitation

<post processing>

(1) Water cleaning

(2) Prevention of discoloration (AT-21, manufactured by Uyemura & Co., Ltd.)

(3) Water cleaning

(4) Drying

<Measurement of tensile strength and elongation>

The copper film prepared above was punched into a dumbbell-shaped test piece of the size shown in Fig. 2, and the elongation before the fracture at a clamping distance of 40 mm and an elongation of 4 mm/min was evaluated by the following equation. And tensile strength.

T[kgf/mm ² ]=F[kgf]/(10[mm]×d[mm])

Where T = tensile strength, F = maximum tensile strength, and d = film thickness of the central portion of the test piece.

E[%]=ΔL[mm]/20[mm]

Where E = elongation and ΔL = elongation length before the film breaks.

Examples 5 to 8 and Comparative Examples 4 to 6

A laminate substrate having a recessed portion having a diameter of 80 μm and a height (depth) of 100 μm was formed on the surface by a plating resist film, and a copper electrolytic plating bath shown in Table 1 was used for the laminate substrate under the following conditions. The recessed portion at which the pillar is to be formed is subjected to copper electrolytic plating. It will be noted that a portion to be formed with an electrolytically plated copper layer is previously subjected to a conventional pretreatment, followed by formation of an electroless copper layer having a thickness of 0.3 μm as a lower layer, and copper electrolytic plating is performed.

<plating conditions>

Cathode current density: 10 ASD (A/dm ² )

Temperature: 35 ° C

Plating time: 36 minutes (corresponding to a column height of 80 μm)

Stirring: slightly stronger air agitation

The shape of the column top after copper electrolytic plating was evaluated for the column profile (i.e., the section along the height). Measure the maximum and minimum heights of the columns and calculate the difference between them. The results are shown in Table 4.

Examples 5 to 8: Based on a suitable uniform effect, a substantially flat column can be obtained, except that the copper layer at the end portion is slightly thin.

Comparative Example 4: The uniform effect was too weak, so the copper layer at the end portion was thin.

Comparative Example 5: The uniform effect was too strong, so the copper layer at the end portion was extremely thick.

Comparative Example 6: The copper layer of the end portion became too thin due to the non-uniform effect.

1. . . Substrate

2. . . Laminated copper

3. . . Electroless copper plating

4. . . Electroplated copper layer

A/B/C/D/E/F. . . section

v. . . Blind via hole

t. . . perforation

1(A) and 1(B) are cross-sectional views of a part of a substrate, respectively, illustrating the measurement of the thickness of the deposit to evaluate the plating thickening ability of the examples and the comparative examples, wherein FIG. 1(A) is a perforation. Sectional view and Fig. 1(B) are sectional views of blind via holes;

Fig. 2 is a schematic view showing the shape and size of a test piece for measuring the physical properties of the deposits of the examples and the comparative examples.

1. . . Substrate

2. . . Laminated copper

3. . . Electroless copper plating

4. . . Electroplated copper layer

A/B/C/D. . . section

t. . . perforation

Claims (6)

A copper electrolytic plating bath comprising copper sulfate (as copper sulfate pentahydrate) in an amount of 50 to 250 g/l, sulfuric acid in an amount of 20 to 200 g/l, and chloride ion in an amount of 20 to 150 mg/l, and a sulfur atom-containing organic compound and a nitrogen atom-containing organic compound as an organic additive, the nitrogen atom-containing organic compound being a nitrogen atom-containing polymer compound, which is obtained by including in an acidic aqueous solution. The porphyrin reacts with the epichlorohydrin of the dimoral to obtain the reaction product, and one to two moles (relative to one mole) The imidazole of the porphyrin is obtained by a two-stage reaction in which the reaction product is further reacted. A copper electrolytic plating bath according to claim 1, wherein the nitrogen atom-containing polymer compound is present in an amount of from 1 to 1000 mg/l. The copper electrolytic plating bath according to claim 1, wherein the sulfur atom-containing organic compound is selected from the group consisting of sulfur atom-containing organic compounds represented by the following formulas (1) to (4), and is present in an amount of 0.001 to 100 mg/ lH─S─(CH ₂ ) _a ─(O) _b ─SO ₃ M (1) Wherein R ₁ , R ₂ and R ₃ independently represent an alkyl group having 1 to 5 carbon atoms, M represents a hydrogen atom or an alkali metal, a is an integer of 1 to 8, and b, c and d are each 0 or 1. A copper electrolytic plating method comprising electroplating an object to be electroplated at a temperature of 30 to 50 ° C in a copper electrolytic plating bath according to any one of claims 1 to 3. The copper electroplating method of claim 4, wherein the object to be electroplated is a substrate having perforations, blind via holes or pillars. The copper electrolytic plating method of claim 5, wherein the perforation has a diameter of 0.05 to 2.0 mm, a height of 0.01 to 2.0 mm, and an aspect ratio of 0.1 to 10, and the diameter of the blind via hole is 20 to 300 μm. The height is 20 to 150 μm, and the column has a diameter of 30 to 300 μm, a height of 25 to 200 μm, and an aspect ratio of 0.2 to 3.