JPS59211564A - Chemical copper plating solution - Google Patents

Abstract

PURPOSE:To permit high speed deposition of a copper plating film and to improve the ductility of the plating film by adding a proper amt. of specific cuprous ion complexing agent and nonionic surface active agent to a chemical copper plating soln. contg. a copper salt, cupric ion complexing agent, reducing agent and a pH adjusting agent. CONSTITUTION:1-200mg/l At least one kind among the cuprous ion complexing agents expressed by the formulas ( I ), (II), (III) and 10mg/l-5g/l at least one kind among the nonionic surface active agents expressed by the formulas (IV), (V), (VI) are added to a soln. contg. a copper salt such as copper sulfate, cupric ion complexing agent, paraform aldehyde as a copper ion reducing agent, NaOH as a pH adjusting agent, etc. as a chemical copper plating soln. The chemical copper plating soln. is used at 50-80 deg.C and 10.8-13.0pH, by which a copper plating film having excellent ductility is chemically plated at a high rate of deposition on the surface of a material to be plated.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a chemical copper plating solution, and more particularly to a novel chemical copper plating solution that is capable of high-speed deposition and that can form a matted film with excellent mechanical properties and spreadability. Regarding the composition of Ihigaku copper plating solution.

[Technical background of the invention and its problems]

Chemical copper plating solutions usually include cupric salts such as steel sulfate, copper nitrate, and cupric chloride; ethylenesoaminetetraacetic acid, N, N, N
',N'-tetrakis=(2-hydroxypropyl)-
complexing agents such as ethylenesoamine, Rothsell's salt; reducing agents such as formaldehyde, dimethylamine borane, sodium boronoylide; Contains anti-inflammatory drugs.

However, the chemistry of the composition consists only of these ingredients!
The matted film obtained from the 111J plating solution is generally brittle and has insufficient mechanical properties, especially spreadability, for practical use. For example, in manufacturing printed wiring boards using the so-called additive method in which the 'yh electric circuit part of the printed wiring board is formed by chemical copper plating, thermal stress and physical shock due to processing of the printed wiring board and environmental changes may occur. circuit breakage is likely to occur.

In order to improve the above drawbacks, copper salts, complexing agents, reducing agents, p
Attempts have been made to improve the spreadability of the chemical copper plating film by further adding polyethylene glycol, phenanthrolines, or water-soluble cyanides to the chemical copper plating solution having the composition of HRI7a conditioning agent. .

However, even if the above-mentioned components are added, the spreadability of the chemical copper plating film is only slightly improved, and the mechanical properties of the plating film are 1:1. However, we have not yet reached the point where it is possible.

Moreover, when these additional components are added, the problem that the deposition rate of plating becomes slow and productivity is reduced inevitably occurs.

[Purpose of the invention]

11. It is an object of the present invention to provide a tack plating solution having a novel composition that enables rapid plating deposition and provides a copper plating film with improved mechanical properties, especially ductility.

[Summary of the invention]

The chemical copper plating solution of the present invention is a chemical tM plating solution containing a copper salt, a second pyramidal ion marking agent, a reducing agent, and a pH adjuster, and further comprises the general formula (■): (wherein R1, R2 may be the same or different and each represents a hydrogen atom, a phenyl group, or a substituted phenyl group.) A cuprous ion leading agent represented by the general formula (■); (wherein, R8 , R', Rr', and R' may be the same or different, and each represents a hydrogen atom, carbon, Gl
~4 alkyl group. ) A cuprous ion complexing agent represented by the general formula Q11): (wherein, R' and R8 may be the same or different, and each represents a hydrogen atom or R7 and R8 together. R may form an aromatic ring or a substituted aromatic ring
", R"' may be the same or different and each represents an alkyl group having 1 to 4 carbon atoms. ) A cuprous ion lead agent represented by; at least one cuprous ion complexing agent selected from the group of; and the general formula: (where ml represents an integer of 1 or more. ) Nonionic surfactant represented by general formula (V): (wherein, m2.nl each represents an integer of 1 or more.

) A nonionic surfactant represented by; General formula ('VD: (In the formula, ml and nl each represent an integer of 1 or more.

) A nonionic surfactant represented by: The nonionic surfactant is characterized by containing at least one nonionic surfactant listed in A J1 to J5h.

The chemical copper plating solution of the present invention contains, in addition to four components: a copper salt, a cupric ion complexing agent, a retrograde agent, and a -l adjustment agent, a cuprous ion lead agent and a nonionic copper ion plating agent, which will be described later. System surface activity (<1.
It is composed of two components:

Among these components, the copper salt supplies copper ions, and the reducing agent reduces the copper ions to a metallic state.

The cupric ion complexing agent forms a stable complex with the cupric ion to prevent the formation of hydroxide (2@) in the plating bath (alkaline), and the p"ffl'lJl agent forms a stable complex with the cupric ion. Adjust the optimum plating deposition potential in. All of these components can be those conventionally used in the preparation of chemical copper plating solutions.

Cuprous ion complexing agent and nonionic surfactant f, i, 1 for this ¥14 light prevent the self-decomposition effect of the plating solution, improve the stability of the solution, and improve the mechanical properties of the precipitated plating film. It is a component that contributes 1j to the improvement of characteristics.

First, the cuprous ion complexing agent will be explained.

Examples of the cuprous ion complexing agent to be used include at least one TiX of the compounds represented by the general formula (I), the general formula (■), and the general formula (2)4. In the compound (1), R'', R2 may be the same or different, and each represents a hydrogen atom; a phenyl group; a benzenesulfone H,':= natD It #
*7x Nyl group. Among these, in the present invention, 3-(2-gyrinor)-1,2,4-triazine, 3-(2-pyridyl)-5,6-diphenyl-1゜2
．． 4-triazine, 3-(2-pyridyl)-6-phenyl-1,2,4-triazine, 3-(2-pyrisol)-
5,6-diphenyl-1,2,4-triazine-1+,
', P'-disulfonic acid, 3-(2-pyridyl)-6-
Phenyl-1,2,4-triazine-p-disulfonic acid and the like are preferred.

In compound (11), R", R', R',
R' may be the same or different, and each is a hydrogen atom, a lower alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl group, or a butyl group. Among these, in the present invention, 2,2'-bis (5°6
-Simethyl-1,2,4-triazine), 2,2'-bis(5,G-S'ethyl-1,2,4-triazine),
2,2'-bis(5,6-soderobyl-1°2.4-triazine), 2,2'-bis(5,6-cyptyl-1.
2.4-) Rhiannon) etc. are well received.

In the compound (In), R' and R' may be the same or different, and each is a hydrogen atom; a hydroxyl group, or R7 and R8 together form an aromatic ring such as quinoxaline or a 6,7-dualky A group that forms a substituted aromatic ring with quinoxaline, sweet R9, RIG
may be the same or different, and each represents a methyl group, an ethyl group, and a propyl group.

It is a lower alkyl group having 1 to 4 carbon atoms such as a butyl group.

Among these, in the present invention, 6,7-nomethyl-2,3-di(2-birituru)-quinoxaline, 2,3-
Bis(6-methyl-2-linol)-5,6-cyhydroviradun, 2,3-bis(6-methyl-2-birituru)
-Quinoxaline, 2.3-bis(2-birituru)-quinoxaline, 2.3-bis(6-ethyl-2-pyridyl)
-quinoxaline, 2,3-bis(6-butyl-2-pyridyl)-5,6-cyhydrobirazine, 6,7-danityl-2,3-so(2-birityl)-quinoxaline, and the like are preferred.

These copper ion lead agents form stable complexes with cuprous ions produced as a side reaction product in chemical copper plating, stabilize the plating solution, and This prevents the precipitation of and contributes to improving the mechanical properties of the plating film.

The concentration of cuprous ion complexing agent in the plating solution is 1 m
It is preferably in the range of g/t to 2oomti7t. If the temperature is less than 1vy/l, the effect of improving the spreadability of the plating film will not appear, and if it exceeds 200mg/l, the effect of improving the spreadability of the plating film will not only reach a saturated state and become meaningless, but also The deposition rate of the plating decreases rapidly, leading to a decrease in nest-building efficiency.

Next, the nonionic surfactant will be explained.

The nonionic surfactant used is at least one of the compounds represented by the general formula (iv), the general formula (V), and the -112 formula (b).

Compound: i') JQV) is 2 and m1iITj is an anvil of 1 or more.

When ml is 0, the corresponding active agent has a small solubility in ml.
Therefore, it is difficult to improve the spreadability of the plating film.

As the ml increases by 11, the resulting plating skin 1i
! , IA of the ship! ffl '1'l: also improves, but its effect almost reaches its upper limit around m1 = 20, and 'j'jji
Be in a state of peace. Therefore, from the viewpoint of force and workability, there is no particular upper limit for nil, and ml is preferably a value of 500 or less.

Compound 1'・su(V), compound (in VD, m2,
m3, Ill, n,.

Each leaf is an integer greater than or equal to 1, and in combinations where either one is 0 (t-,, the same inconvenience as described for compound θ■ will occur.For compound (■) and compound (b), m2
As 111-1, m, and In2 increase by + and 7, respectively, the spreadability improves, but the effect reaches a saturation state around 20 in all cases. m2+ n+, m4
+ R2 is preferably a value of 500 or less.

8 history of ionic surfactants in plating solutions? Z
The range of i-,, 1omy/l to 30 v/l is preferable, and the range of 30 WI/L to 20 g/L is particularly suitable for the case where n11, m, 10n1, m3+n are each less than 20. So, m, , m2+n, , m,
If each of 10 n2 is 20 or more, 10 wi
/ L ~ 5'? A range of /l is preferred.

Preferred plating conditions for using the chemical copper plating solution of the present invention are a temperature range of 50 to 80°C, more preferably 60 to 75°C, and a pH of 10.8 to 13.0, furthermore 11.8 to 1.
It is in the range of 2.5. According to such plating conditions, the characteristics of the plating solution of the present invention can be fully utilized, and a plating film that is capable of high-speed deposition and has excellent spreadability can be obtained.

[Embodiments of the invention]

Examples 1 to 24 A stainless steel plate of F4 and 0.3 ran was polished with a cleanser, immersed in 10% sodium hydroxide solution at 80°C for 5 minutes, taken out, washed with water, and then soaked in 10 drops of hydrochloric acid at room temperature. After soaking for 5 minutes and washing with water to clean the surface, the obtained stainless steel plate was converted into 3M.
50 y/hydrochloric acid
The sample was immersed in a solution having a composition of 10 mvt water and the remainder for 2 minutes, and washed under running water for 1 minute. Next, palladium chloride 0.25? /
Hydrochloric acid 104 Water
The sample was immersed in a solution with the remaining composition for 1 minute, and then washed under running water for 1 minute. After that, copper sulfate (pentahydrate) 0.04
Mol Cupric Ion Leading Agent 0.1
Molparaformaldehyde 0
．． The force required to reduce 1 mol of sodium hydroxide to 12.3 and the cuprous ion saturant
Appropriate amount of nonionic surfactant
We prepared various chemical copper plating solutions with compositions in which an appropriate amount of water and the remainder were removed.

Next, a plated film of 30 to 35 μm was deposited on each of the front and back surfaces of a 0.3 m thick stainless steel plate which had been catalyzed in the chemical copper plating solution as described above. The plating conditions were as follows: plating temperature: 0°C, plating solution p)l: 12.
It was 3.

The copper plating film thus obtained was peeled off from the stainless steel plate and subjected to a ductility test. The spreadability is as follows18
It was measured by a 0° bending test.

First, the plating film is bent 180° in one direction to create a crease, and then returned to its original position and pressure is applied to flatten the crease. These operations are counted as one bending. These operations are repeated until the plating film breaks at the crease. In this test method, the ductility of the plating film is expressed by the number of bends the plating film withstands.

Further, the above-mentioned plating film was subjected to a tensile test.

That is, Shimadzu Autograph (Model DSS-
5000), cut a test piece into 12.7 x 150 pieces, chuck distance fi: 100wn, pulling speed =
Tensile strength (Kf/J) and elongation rate (resistance) were measured under the condition of 5 ropes/min.

The above results are collectively shown in the table in correspondence with all the copper plating solutions of various compositions. In addition, the precipitation rate of each copper plating film (μm
/hr) is also written. Numbers 1 to 24 in the table are the materials U of the present invention.

In addition, in the table, compound side, compound (■, compound (Ml'e
A-x, B-x, C-x"?' table wa L, A-x respectively
K L-X in m+, B-x in m2+
The X added by adding n□ to C-x represents ms+ntk, respectively.

〔Effect of the invention〕

As is clear from the above explanation, the chemical copper plating solution of the present invention (c) has a very high deposition rate, and at the same time has a high mechanical property, Ik property, especially bending strength (as shown above). It forms a copper plating film with poor ductility, and is useful when applied to the creation of conductive circuits for U1 printed distribution boards, for example.

Claims (1)

[Claims] A chemical copper plating solution containing a copper salt, a cupric ion lead agent, a reducing agent, and a PH adjuster, further comprising the general formula (I): (wherein R" and R' are (which may be the same or different and each represents a hydrogen atom, a phenyl group, or a phenyl group); General formula (11); , R4, R5, and RO may be the same or different and each represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.) A cuprous ion lead agent represented by the general formula (1 ■) (In the formula, R' and R'' may be the same or different, and each is a hydrogen atom, or R7 and R8 together form an aromatic ring or a substituted aromatic ring. Moyo (: R11 and Rlo may be the same or different and each represents an alkyl group having 1 to 4 carbon atoms.) At least one selected from the group of: One type of cuprous ion complexing agent, and a nonionic surfactant represented by the general formula (V): (where nll represents an integer of 1 or more); General formula (V): ( (In the formula, m2.nl each represents an integer of 1 or more.) A nonionic surfactant represented by the general formula (Vlll: (In the formula, 1113 and nzlrF each represent an integer of 1 or more.) A chemical copper plating solution containing at least one nonionic surfactant selected from the group of: