KR20160008775A - Electrolytic copper stripping composition for stainless steel jigs - Google Patents

Abstract

The present invention relates to a copper electrolysis stripping solution composition for a stainless jig which does not contain NOx, and is connected to an anode by dipping a plating target jig to a stripping solution of a stripping tank. Desirably, the copper electrolysis stripping solution composition of the present invention can have alkylsulfonic acid as a main component; and moreover desirably, can have methanesulfonic acid (MSA) or propane sulfonic acid (PSA) and copper as the main components.

Description

TECHNICAL FIELD [0001] The present invention relates to a copper electrolytic stripping solution composition for a stainless steel jig,

The present invention relates to a copper electrolytic stripping agent composition, and more particularly to a stripping solution composition for electrolytically stripping copper plated on a stainless steel jig.

Copper plating is the most widely used plating method across a variety of industries. In order to perform copper plating, there must be a jig for fixing the plated body. They usually use a stainless steel jig. During the plating process, they are copper plated like plated bodies. In order to achieve a superior and precise plating quality for the plated body, it is essential to peel off the plating applied to the jig.

Conventional techniques used for peeling copper metal on a jig mainly use immersion type peeling method using nitric acid or sulfuric acid and hydrogen peroxide. For example, Korean Patent No. 948264 discloses a technique for depositing a jig that does not require plating in a nitric acid tank at a temperature of about 60 degrees for 5 minutes to peel off.

However, this immersed separation method has the disadvantages that the generation of NOx gas, the cyclic rebuilding bath, the severe exothermic reaction, and the environmental pollution caused by the disposal of the molten copper metal, Disposal and the like.

The inventors of the present invention have accomplished the present invention by researching for a long time in order to solve the above problems and technical disadvantages.

It is an object of the present invention to propose a novel method of stripping copper plating of a jig by using the principle of electroplating technology in reverse. That is, instead of applying the negative electrode to the jig, the positive electrode is applied to peel the plated copper metal on the jig according to the electroplating principle. Thus, the present invention proposes a technology capable of recovering valuable metals and recycling them as resources by eliminating NOx gas generation and exothermic reaction, which was a problem of the prior art.

Another object of the present invention is to provide a novel copper electrolytic stripping agent composition which more effectively ensures copper plating separation on a jig.

On the other hand, other unspecified purposes of the present invention will be further considered within the scope of the following detailed description and easily deduced from the effects thereof.

In order to achieve the above object, the present invention provides a method of manufacturing a semiconductor device, in which a plated body jig is immersed in a peeling solution of a peeling tank,

A copper electrolytic stripping solution composition for a stainless steel jig containing no NOx, characterized by a copper electrolytic stripping solution composition comprising an alkylsulfonic acid as a main component.

In the copper electrolytic release solution composition according to a preferred embodiment of the present invention, methanesulfonic acid (MSA) and copper are used as the main component.

In addition, in the copper electrolytic release solution composition according to a preferred embodiment of the present invention, the peeling tank preferably contains 80 to 450 g / l of MSA per 10 g / l of copper as a weight based on the volume.

In another preferred embodiment of the present invention, the copper electrolytic dissolution solution composition may contain propane sulfonic acid (PSA) and copper as main components.

In the above embodiment, it is preferable that the peeling tank contains 70 to 580 g / l of PSA per 10 g / l of copper as a weight to volume.

In the copper electrolytic dissolution solution composition according to another preferred embodiment of the present invention, the plated body jig is immersed in the dissolution solution of the dissolution tank and connected to the positive electrode,

It is preferable that the copper electrolytic stripping solution composition for stainless steel jig not containing NOx contains MSA or PSA as a main component and copper ions to be added are formed by dissolving copper methane sulfonic acid, copper oxide or copper metal.

Further, in the copper electrolytic release solution composition according to the preferred embodiment of the present invention, the copper electrolytic release solution composition may further include at least one additive which essentially comprises a carrier, a leveler, have.

According to the present invention, by peeling the copper plating on the stainless steel jig, the following advantages can be obtained:

First, NOx gas free working environment can be obtained, which is beneficial to safety and environment of workers. Second, since there is no strong exothermic reaction generated by the reaction between copper and concentrated nitric acid, there is no explosion of solution and generation of gas due to exothermic reaction. Thirdly, in the conventional technique, if a metal of a certain capacity is peeled off, the solution life is over and a rebuilding process is required. However, the present invention is very economical since it is necessary to correct only the solution that is buried in the jig. For example, in the case of using sulfuric acid, and the reconstruction bath necessary because the consumption of sulfuric acid and hydrogen peroxide by the reaction to the copper metal in sulfuric acid and hydrogen peroxide, in the case of using the nitric acid there, and the NO ₂ gas by the reaction of copper with nitric acid occurs HNO ₃ But it is not necessary to use such a reconstruction bath in the present invention.

Fourth, there is no decrease in utilization rate due to waste water treatment and shutdown of equipment, which are incidental expenses due to reconstruction. Fifth, it is possible to reduce the cost of wastewater treatment of the stripping solution whose solution life has expired. Sixth, it is possible to recycle valuable metals that are dumped into wastewater and reuse them, so that resources can be recycled and economic benefits can be obtained. Finally, there is no corrosion on the raw metal, which can prolong the life of the jig.

Even if effects not specifically mentioned in the specification of the present invention are incorporated, the provisional effects expected by the technical features of the present invention are treated as described in the specification of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

In a preferred embodiment of the present invention, a plating bath (abbreviated as " peeling bath ") for peeling the copper plating applied to the jig is immersed. In the structure of the peeling tank, the plated stainless steel jig is connected to the anode, and the cathode is connected to the stainless steel plate, so that the plated copper metal can be peeled off from the jig. In the present specification, " jigs " is expressed in singular form, but it should be understood as an aggregate noun including a plurality of jigs.

In order to effectively remove the copper plating of the jig in the peeling tank having the above-described structure, the inventors of the present invention first performed the task of checking the threshold voltage of the stainless steel metal in the peeling solution of the peeling tank. Means the limit voltage that can be stripped without corrosion of the material metal (stainless steel). The inventors of the present invention have shared the scientific reasoning that the amount of current flowing below this threshold voltage can shorten the stripping time. This is because if the peeling time is long, the length of the peeling machine becomes longer and the installation site and the installation cost are increased.

As the composition of the peeling solution in the peeling tank, the plating solution composed mainly of sulfuric acid and copper sulfate could be used first. However, I came to the conclusion that such an approach is actually very difficult to apply to the process, for the same reason. In other words, the peeling solution composition containing sulfuric acid and copper sulfate as main components has a low threshold voltage and accordingly has a small amount of peeling current and low peeling speed. These problems have made it difficult to apply to practical processes, and therefore, a further improved release solution composition is required.

Comparative Examples 1 to 4 For the measurement of the threshold voltage for the SUS304 of the composition, the SUS304 specimen was fabricated to have a cathode size of 6 × 5 cm and an anode size of 1 × 2.5 cm. The basic composition of the peeling solution for the comparative example for measuring the threshold voltage was a sulfuric acid and copper sulfate electrolytic peeling solution, and the solution compositions of Comparative Examples 1 to 4 and the results are shown in Table 1. Also, the compositions of the additives used in Comparative Examples 1 to 4 are the same as those of the additive composition 1.

≪ Additive composition 1 >

PEG 8000: 1.0 g / l

Janus green B: 1.0 mg / l

3-mercapto propane sulfonic acid (MPSA): 5.0 mg / l

Solution composition Threshold voltage measurement Copper Sulfuric acid Chlorine ion 1.1V 1.2V 1.3V Threshold voltage Comparative Example 1 10 g / l 100 g / l 80 mg / l 0.00A 0.05A - 1.2V Comparative Example 2 10 g / l 150 g / l 80 mg / l 0.00A 0.07A - 1.2V Comparative Example 3 20 g / l 100 g / l 80 mg / l 0.00A 0.00A 0.06A 1.3V Comparative Example 4 20 g / l 150 g / l 80 mg / l 0.05A - - 1.1V

As in Comparative Examples 1 to 4, the threshold voltage was measured at a level of 1.1 to 1.3 V according to the sulfuric acid and copper concentration.

In order to measure the peeling speed for the comparative examples 1 to 4, a time of peeling completely at a threshold voltage or less was measured after plating 15 mu m of copper on the SUS304 specimen.

The composition of the additives used here is the same as that of the additive composition 1, and the experimental results are shown in Table 2.

Solution composition Peeling speed Copper Sulfuric acid (95%) Chlorine ion Comparative Example 1 10 g / l 100 g / l 80 mg / l 300 seconds Comparative Example 2 10 g / l 150 g / l 80 mg / l 270 seconds Comparative Example 3 20 g / l 100 g / l 80 mg / l 330 seconds Comparative Example 4 20 g / l 150 g / l 80 mg / l 300 seconds

As described above, in the compositions containing sulfuric acid and copper sulfate as the main components in Comparative Examples 1 to 4, a rapid peeling rate could not be obtained due to a low threshold voltage. Since the composition of Comparative Example 1 requires a long stripping time in actual use in the field, the length of the equipment becomes long, which causes productivity and manufacturing cost increase. In order to solve the problem of this comparative example, the inventors of the present invention attempted to newly improve the composition of the solution. For example, if a higher threshold voltage than Comparative Example 1 can be obtained through the improvement of the peeling composition, it is determined that the peeling speed can be obtained faster than that of Comparative Example 1, and the composition of the peeling solution is reconstructed as in the following Examples.

The release agent composition of the present invention is preferably composed mainly of alkyl sulfonic acids (Alkylsulfonic Acids). In Examples 1 to 4 of the present invention, methanesulfonic acid was used as a main component, and in Examples 5 to 8 of the present invention, copper plated on a jig was peeled off using propanesulfonic acid as a main component. The details will be described below.

In Examples 1 to 4 of the present invention, methane sulfonic acid (MSA) and copper are used as main components instead of sulfuric acid and copper as the main components, and chlorine Ions and the additive composition 1 were added to reconstitute the solution. The additive makes the copper metal film peeled off from the negative electrode.

The composition of the additive is related to how well the exfoliated copper metal adheres to the surface of the negative electrode. The additive makes the copper metal film peeled off from the negative electrode. The additive composition may include a carrier, a leveler, and a brightener. Particularly, the carrier component in the peeling solution must be added. As the carrier component, polyoxyethylene-polyoxypropylene glycol, octylphenol ethoxylate, ethylene oxide propylene oxide copolymer, Ethylenediamine-ethoxylate-propoxylate have. As the leveler component, polyvinyl pyrrolidone, polyvinyl imidazole chloride, Quarternary ammonium derivative, thiourea, quaternized polyamine, imidazole and derivatives thereof may be used in addition to Janus green B. As polishes, polishes such as Bis- (3-sulfopropyl) disulfide (SPS), N, N-dimethyl-dithiocarbamylpropyl sulfonic acid (DPS) and 3- (benzothiazolyl-2-mercapto) -propylsulfonic acid .

On the other hand, the copper ion may be added by directly dissolving copper methane sulfonic acid, copper oxide, or metal copper. In addition, the chloride ion may be added by hydrochloric acid, sodium chloride or potassium chloride.

Solution composition Copper MSA (70 wt%) Chlorine ion Example 1 10 g / l 80g / l 80 mg / l Example 2 10 g / l 100 g / l 80 mg / l Example 3 10 g / l 150 g / l 80 mg / l Example 4 10 g / l 200 g / l 80 mg / l

The method of measuring the intergranular voltage for the compositions of Examples 1 to 4 is the same as the method for measuring the threshold voltage of the comparative composition. For the threshold voltage measurement test for SUS304, SUS304 was used as a sample for a cathode size of 6 x 5 cm, And the experiment was conducted under the conditions of 12: 1 ratio of cathode and anode. The basic composition of the peeling solution for the measurement of the threshold voltages of Examples 1 to 4 was the methanesulfonic acid and the copper electrolytic peeling solution which were improved in the present invention as described above and the solution compositions of Examples 1 to 4 and the results are shown in Table 3 Respectively. The results of the threshold voltage measurement in these embodiments are shown in Table 4.

1.0V 1.5V 1.8V 1.9V Threshold voltage Example 1 0.00A 0.00A 0.00A 0.09A 1.9V Example 2 0.00A 0.00A 0.00A 0.07A 1.9V Example 3 0.00A 0.00A 0.09A - 1.8V Example 4 0.00A 0.00A 0.04A - 1.8V

The maximum conductivity of MSA was measured to be about 450 g / l, and when it was more than 450 g / l, it was analyzed that the conductivity would be rather reduced and the flow of current would be disturbed. In addition, there is a problem that the drag-out loss increases and the economical efficiency is deteriorated.

As shown in Examples 1 to 4, the threshold voltage was measured at 1.8 to 1.9 V according to MSA and copper concentration. In Examples 1 to 4, a synergistic effect of 0.6 to 0.8 V was obtained as compared with Comparative Examples 1 to 4.

In order to measure the peeling speed for Examples 1 to 4, the SUS304 specimen was plated with 15 mu m of copper, and the time for completely peeling at a threshold voltage or less was measured. The composition of the additives used here is the same as that of the additive composition 1, and the experimental results are shown in Table 5.

Solution composition Peeling speed Copper MSA (70 wt%) Chlorine ion Example 1 10 g / l 80g / l 80 mg / l 280 seconds Example 2 10 g / l 100 g / l 80 mg / l 250 seconds Example 3 10 g / l 150 g / l 80 mg / l 210 seconds Example 4 10 g / l 200 g / l 80 mg / l 190 seconds

As can be seen from the above example, the threshold voltage of the stripping solution using MSA was about 1.9 Volt, which was nearly twice higher than the threshold voltage of about 1.1 Volt of the stripping solution using the sulfuric acid of the comparative example. At this time, the peeling time of the specimen plated with copper of 15 mu m was 190 to 280 seconds in each of Examples, and the results were improved as compared with Comparative Examples 1 to 4 in which the peeling time was 270 to 330 seconds. In the case of Example 1, although data showing slower than the peeling time of Comparative Example 2 is shown, it can be seen as an almost equal peeling time and the advantage of no need for a rebuilding bath is obtained. And it can be said that it is better. These results show that it is possible to completely overcome the disadvantages of using the sulfuric acid as a main component, which is difficult to apply to the actual production site at a too slow peeling speed, and it is concluded that there is no problem in field application.

In another preferred embodiment of the present invention, propane sulfonic acid (PSA) was used as the electrolyte in the stripping tank. The threshold voltage was measured for the compositions of Examples 5 to 8 of the present invention. SUS304 was used for the threshold voltage measurement test for SUS304 in the same manner as the threshold voltage measurement method for the comparative example composition, 6 × 5 cm, anode size 1 × 2.5 cm, and the experiment was conducted under the conditions of 12: 1 ratio of anode to cathode. The electrolytic peeling solution using propane sulfonic acid instead of the methanesulfonic acid of Examples 1 to 4 was used as the basic constitution of the peeling solution for the threshold voltage measurement of Examples 5 to 8, The results of the measurement of the threshold voltage in the measured examples are shown in Table 7.

Solution composition Copper PSA (100 wt%) Chlorine ion Example 5 10 g / l 70 g / l 80 mg / l Example 6 10 g / l 90 g / l 80 mg / l Example 7 10 g / l 135 g / l 80 mg / l Example 8 10 g / l 180 g / l 80 mg / l

1.0V 1.5V 1.8V 1.9V Threshold voltage Example 5 0.00A 0.00A 0.00A 0.08A 1.9V Example 6 0.00A 0.00A 0.00A 0.06A 1.9V Example 7 0.00A 0.00A 0.08A - 1.8V Example 8 0.00A 0.00A 0.03A - 1.8V

As shown in Examples 5 to 8, the threshold voltage was 1.8 to 1.9 V according to the concentration of propane sulfonic acid and copper, which was similar to that of MSA. In Examples 5 to 8, a synergistic effect of 0.6 to 0.8 V was obtained as in Examples 1 to 4, as compared with Comparative Examples 1 to 4.

In order to measure the peeling speed for Examples 5 to 8, 15 占 퐉 of copper was plated on the SUS304 specimen in the same manner as in the measurement methods of Examples 1 to 4, and the time for completely peeling at a threshold voltage or less was measured. The composition of the additive used here is the same as that of additive composition 1 as in Examples 1 to 4, and the results of the experiment are shown in Table 8.

Solution composition Peeling speed Copper PSA (100 wt%) Chlorine ion Example 5 10 g / l 70 g / l 80 mg / l 285 seconds Example 6 10 g / l 90 g / l 80 mg / l 253 seconds Example 7 10 g / l 135 g / l 80 mg / l 213 seconds Example 8 10 g / l 180 g / l 80 mg / l 192 seconds

As can be seen from the results of Examples 5 to 8, the threshold voltage of the peeling solution using propane sulfonic acid is about 1.9 Volt, which is almost twice as high as the threshold voltage of about 1.1 Volt of the peeling solution using the sulfuric acid of the comparative example . At this time, the peeling time of the specimen plated with copper of 15 mu m was improved to 192 to 285 seconds in each of the Examples, compared with Comparative Examples 1 to 4 in which the peeling time was 270 to 330 seconds. The data of Example 5 shows data that is slower than the peeling time of Comparative Example 2 but can be regarded as almost the same peeling time and does not require a rebuilding bath, It can be considered excellent. These results show that the method of peeling the copper plating of the jig by constituting the composition of the peeling tank comprising the PSA as the main component of the present invention is also applicable to the production of sulfuric acid As a main component, the disadvantages of the exfoliating agent can be completely overcome. On the other hand, when the weight of PSA is larger than 580 g at 10 g / l of copper, it is analyzed that the conductivity is lowered and the flow of current is interfered, and the amount consumed by jig is increased, kftod.

In addition, the scope of protection of the present invention is not limited to the description and the expression of the embodiments explicitly described above. Further, it should be noted that the scope of protection of the present invention can not be limited due to obvious changes or substitutions in the technical field to which the present invention belongs.

Claims (7)

The plated body jig is immersed in the peeling solution of the peeling tank and connected to the anode,
A copper electrolytic stripping solution composition for a stainless steel jig that does not contain NOx, the copper electrolytic stripping solution composition comprising an alkylsulfonic acid as a main component. The copper electrolytic stripping solution composition according to claim 1, comprising methanesulfonic acid (MSA) and copper as a main component. The copper electrolytic release solution composition according to claim 2, wherein the peeling tank contains 80 to 450 g / l of MSA per 10 g / l of copper as a weight based on the volume. The copper electrolytic stripper composition according to claim 1, wherein the copper electrolytic stripper solution composition comprises propane sulfonic acid (PSA) and copper as main components. 4. The copper electrolytic release solution composition according to claim 3, wherein the peeling tank contains 70 to 580 g / l of PSA per 10 g / l of copper as a weight based on the volume. The plated body jig is immersed in the peeling solution of the peeling tank and connected to the anode,
A copper electrolytic stripping solution composition for a stainless steel jig containing no NOx, wherein the copper electrolytic stripping solution composition comprises MSA or PSA as a main component and copper ions to be added are formed by dissolving copper methane sulfonic acid, copper oxide or copper metal . The copper electrolytic release solution composition according to any one of claims 1 to 6, further comprising at least one additive which essentially comprises a carrier, a leveler, and a carrier of a brightener.