Deoxidation composition and preparation method thereof

Abstract

The invention discloses a deoxidation composition and a preparation method thereof, and relates to the technical field of deoxidation process, the deoxidation composition comprises 1-15% of inorganic acid, 1-5% of organic acid, 5-25% of peroxide, 0.1-3% of complexing agent, 0.01-5% of surfactant and 40-80% of water. According to the deoxidation composition provided by the invention, the complexing agent and the surface complexing agent are added, so that a deoxidation solution has a good etching rate, relatively high copper solubility, excellent copper surface roughness, excellent plating discoloration resistance and high working efficiency, and can be produced and used on a large scale.

Description

Technical Field

[0001] The present invention relates to the technical field of deoxidation technology, and in particular to a deoxidation composition and a preparation method thereof. Background Art

[0002] With the development of the IC lead frame packaging industry, the requirements for product quality are getting higher and higher. In the manufacturing process of IC lead frames, oxidation of the copper substrate surface is almost inevitable. If it is not removed, or there is residue after removal or the surface uniformity is poor, it will cause plating defects and affect the reliability of the product, leading to problems such as product leakage, shedding, discoloration, etc., affecting the electrical conductivity of the device, and seriously causing the chip to fail or even be scrapped. Therefore, the deoxidation process is a very important pre-treatment process of the IC lead frame packaging process.

[0003] The existing deoxidation solution for stripping the copper oxide layer of the lead frame mainly consists of inorganic acid and oxidant. Among them, the deoxidation solution with sulfuric acid and persulfate as the main components is more commonly used. The disadvantages of this type of sulfuric acid deoxidation solution are: unstable deoxidation rate, low copper dissolution, rough surface of the copper frame, and poor glossiness of the treated copper surface.

[0004] Therefore, a deoxidation composition having a stable deoxidation rate, a large amount of copper dissolution, and a uniform copper frame surface and a preparation method thereof are provided to solve the above problems. Summary of the invention

[0005] In view of the problems in the related art, the present invention provides a deoxidation composition and a preparation method thereof to overcome the above technical problems existing in the existing related art.

[0006] To this end, the specific technical scheme adopted by the present invention is as follows: On the one hand, the present invention provides a deoxidation composition, which comprises the following components in mass percentage:

[0007]

[0008] Preferably, the inorganic acid includes at least one of sulfuric acid, nitric acid, hydrochloric acid and methanesulfonic acid.

[0009] Preferably, the organic acid includes at least one of citric acid, oxalic acid, acetic acid, malonic acid, tartaric acid and malic acid.

[0010] Preferably, the peroxide includes at least one of sodium persulfate, potassium persulfate, potassium monopersulfate, ammonium persulfate and hydrogen peroxide.

[0011] Preferably, the complexing agent includes at least one of ethylenediaminetetraacetic acid, thiourea, aspartic acid, iminotetraacetic acid, lysine, benzotriazole, aminotri(methylenephosphonic acid) and hydroxyethylidene diphosphonic acid.

[0012] Preferably, the surfactant includes at least one of fatty amine polyoxyethylene ether (AEO), sodium lauryl sulfate, sodium phenylpropane dithiopropane sulfonate, sodium ethyl-mercaptobenzothiazole-3-propane sulfonate, and acrylic acid ester nonionic fluorocarbon.

[0013] On the other hand, the present invention also provides a method for preparing a deoxidation composition, which is used to prepare the above-mentioned deoxidation composition, comprising the following steps:

[0014] S1. Prepare the cleaned reactor and filtration system for standby use;

[0015] S2. Weigh 40-80% pure water, add the pure water into the reactor, start the reactor to stir, add 1-5% organic acid, stir for 30-50 minutes, so that the organic acid is completely dissolved;

[0016] S3. Slowly add 1-15% of inorganic acid into the reactor, stir until completely dissolved, cool to 15-35°C, add 5-25% of peroxide, and stir for 30 minutes until the peroxide is completely dissolved;

[0017] S4, adding 0.01-5% of a surfactant and 0.1-3% of a complexing agent into the reaction kettle in proportion, stirring for 20 minutes to completely dissolve the surfactant, and obtaining a mixed solution;

[0018] S5. Introduce the mixed solution in the reaction kettle into a filtration system to filter and obtain a deoxidized solution.

[0019] Preferably, the filter element of the filtration system is a 1umPP filter element.

[0020] The beneficial effects of the present invention are:

[0021] The deoxidation composition provided by the invention adds a complexing agent and a surface complexing agent, so that the deoxidation solution has a good etching rate, a large copper solubility, excellent copper surface roughness, anti-plating discoloration ability, high working efficiency, and can be mass-produced and used. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] The present invention provides a deoxidation composition, which comprises 1-15% of inorganic acid, 1-5% of organic acid, 5-25% of peroxide, 0.1-3% of complexing agent, 0.01-5% of surfactant and 40-80% of water. The inorganic acid comprises at least one of sulfuric acid, nitric acid, hydrochloric acid and methanesulfonic acid; the organic acid comprises at least one of citric acid, oxalic acid, acetic acid, malonic acid, tartaric acid and malic acid; the peroxide comprises at least one of sodium persulfate, potassium persulfate, potassium monopersulfate, ammonium persulfate and hydrogen peroxide; the complexing agent comprises at least one of ethylenediaminetetraacetic acid, thiourea, aspartic acid, iminotetraacetic acid, lysine, benzotriazole, aminotri(methylenephosphonic acid) and hydroxyethylidene diphosphonic acid.

[0024] The deoxidation composition has good etching rate, large copper solubility, excellent copper surface roughness, anti-plating discoloration ability, high working efficiency, and can be mass-produced and used.

[0025] The preparation method of the deoxidation composition comprises the following steps:

[0026] S1. Prepare the cleaned reactor and filtration system for standby use;

[0027] S2. Weigh 40-80% pure water, add the pure water into the reactor, start the reactor to stir, add 1-5% organic acid, stir for 30-50 minutes, so that the organic acid is completely dissolved;

[0028] S3. Slowly add 1-15% of inorganic acid into the reactor, stir until completely dissolved, cool to 15-35°C, add 5-25% of peroxide, and stir for 30 minutes until the peroxide is completely dissolved;

[0029] S4, adding 0.01-5% of a surfactant and 0.1-3% of a complexing agent into the reaction kettle in proportion, stirring for 20 minutes to completely dissolve the surfactant, and obtaining a mixed solution;

[0030] S5. Introduce the mixed solution in the reaction kettle into the filtration system to filter and obtain a deoxidized solution; wherein the filter element of the filtration system is a 1umPP filter element.

[0031] Comparative Example 1

[0032] This comparative example provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate and 72% water.

[0033] Example 1

[0034] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.2% aminotri(methylene)phosphoric acid and 71.8% water. Different from Comparative Example 1, this embodiment contains 0.2% of the complexing agent: aminotri(methylene)phosphoric acid, and the water content is reduced to 71.8%.

[0035] Example 2

[0036] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.2% ethylenediaminetetraacetic acid and 71.8% water. Different from the embodiment 1, the complexing agent in this embodiment is ethylenediaminetetraacetic acid.

[0037] Example 3

[0038] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.05% sodium dodecyl sulfate and 71.95% water. Different from Comparative Example 1, this embodiment contains 0.05% surfactant: sodium dodecyl sulfate, and the water content is reduced to 71.95%.

[0039] Example 4

[0040] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.05% acrylate nonionic fluorocarbon and 71.95% water. Different from embodiment 3, the surfactant in this embodiment is acrylate nonionic fluorocarbon.

[0041] Example 5

[0042] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.2% aminotri(methylene)phosphoric acid, 0.05% sodium dodecyl sulfate and 71.75% water. Different from Example 3, this embodiment also includes 0.2% of a complexing agent: aminotri(methylene)phosphoric acid, and the water content is reduced to 71.75%.

[0043] Example 6

[0044] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.2% ethylenediaminetetraacetic acid, 0.05% sodium dodecyl sulfate and 71.75% water. Different from embodiment 5, the complexing agent is ethylenediaminetetraacetic acid.

[0045] Example 7

[0046] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.2% aminotrimethylphosphonic acid, 0.2% ethylenediaminetetraacetic acid, 0.05% acrylate nonionic fluorocarbon and 71.55% water. Different from Embodiment 1 and Embodiment 2, the complexing agent includes 0.2% aminotrimethylphosphonic acid and 0.2% ethylenediaminetetraacetic acid, the surfactant is 0.05% acrylate nonionic fluorocarbon, and the water content is reduced to 71.55%.

[0047] Example 8

[0048] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.4% aminotri(methylene)phosphoric acid, 0.1% sodium dodecyl sulfate and 71.5% water. Different from Example 7, the complexing agent is 0.4% aminotri(methylene)phosphoric acid, the surfactant is 0.1% sodium dodecyl sulfate, and the water content is reduced to 71.5%.

[0049] Example 9

[0050] This embodiment provides a deoxidation solution, which includes 10% sulfuric acid, 3% citric acid, 15% ammonium persulfate, 0.4% ethylenediaminetetraacetic acid, 0.1% acrylate nonionic fluorocarbon and 71.5% water. Different from Example 8, the complexing agent is 0.4% ethylenediaminetetraacetic acid, and the surfactant is 0.1% acrylate nonionic fluorocarbon.

[0051] The whole TO220 sample was baked at 300°C for 24 hours as a test piece for metal deoxidation test.

[0052] 1) The test piece was completely immersed in 1L of deoxidation solution and taken out after 10 minutes. The etching rate of the test piece was calculated according to the weight reduction of the test piece. The time when the removal rate of the deoxidation solution of Comparative Examples 1-5 and Examples 1-5 was reduced to 30% was recorded, and the copper ion concentration of the deoxidation solution (g / l) was recorded to test the long-term stability and solubility of the deoxidation solution.

[0053] 2) The prepared TO220 test piece was completely immersed in the etching solution and taken out after 1 minute. The roughness of the copper surface before and after deoxidation was observed with a metallographic microscope. At the same time, the deoxidized TO220 was electroplated, neutralized and cleaned, and then the coating was boiled and discolored to test the surface roughness of the frame after deoxidation and the reliability of electroplating.

[0054] Table 1: Stability and solubility results of deoxidation solutions at different times

[0055]

[0056] As can be seen from Table 1, the etching rate of the deoxidation solution with copper complexing agent added provided by the embodiment of the present invention does not change much or almost does not change over time after 50 hours, and has good stability. The deoxidation solution has a greater copper solubility.

[0057] Table 2: Copper surface roughness and coating discoloration of deoxidized solution at different times

[0058]

[0059] In the table, ○ represents discoloration of the coating, △ represents slight discoloration of the coating, and ● represents no discoloration of the coating.

[0060] As can be seen from Table 2, the copper surface roughness and the coating surface of the deoxidation solution provided by the embodiment of the present invention, which contains a copper complexing agent and a surfactant, do not change after 96 hours, and have good stability.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A deoxidation composition, characterized in that The following components are included in percentage by mass:

2. The deoxidation composition according to claim 1, characterized in that The inorganic acid includes at least one of sulfuric acid, nitric acid, hydrochloric acid and methanesulfonic acid.

3. The deoxidation composition according to claim 1, characterized in that The organic acid includes at least one of citric acid, oxalic acid, acetic acid, malonic acid, tartaric acid and malic acid.

4. The deoxidation composition according to claim 1, characterized in that The peroxide comprises at least one of sodium persulfate, potassium persulfate, potassium monopersulfate, ammonium persulfate and hydrogen peroxide.

5. The deoxidation composition according to claim 1, characterized in that The complexing agent includes at least one of ethylenediaminetetraacetic acid, thiourea, aspartic acid, iminotetraacetic acid, lysine, benzotriazole, aminotri(methylenephosphonic acid) and hydroxyethylidene diphosphonic acid.

6. The deoxidation composition according to claim 1, characterized in that The surfactant includes at least one of fatty amine polyoxyethylene ether (AEO), sodium lauryl sulfate, sodium phenylpropane dithiopropane sulfonate, sodium ethyl-mercaptobenzothiazole-3-propane sulfonate, and acrylic acid ester non-ionic fluorocarbon.

7. A method for preparing a deoxidation composition, characterized in that: The preparation method is used to prepare the deoxidation composition according to any one of claims 1 to 6, comprising the following steps: S1. Prepare the cleaned reactor and filtration system for standby use; S2. Weigh 40-80% pure water, add the pure water into the reactor, start the reactor to stir, add 1-5% organic acid, stir for 30-50 minutes, so that the organic acid is completely dissolved; S3. Slowly add 1-15% of inorganic acid into the reactor, stir until completely dissolved, cool to 15-35°C, add 5-25% of peroxide, and stir for 30 minutes until the peroxide is completely dissolved; S4, adding 0.01-5% of a surfactant and 0.1-3% of a complexing agent into the reaction kettle in proportion, stirring for 20 minutes to completely dissolve the surfactant, and obtaining a mixed solution; S5. Introduce the mixed solution in the reaction kettle into a filtration system to filter and obtain a deoxidized solution.

8. The method for preparing the deoxidation composition according to claim 7, characterized in that: The filter element of the filtration system is a 1umPP filter element.

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