CN117878196A - A photovoltaic solar N-type oxide semiconductor ITO chemical copper plating production process - Google Patents

Abstract

The invention discloses a manufacturing process of photovoltaic solar N-type oxide semiconductor ITO electroless copper plating, which comprises the following steps: carrying out surface adjustment treatment on an ITO film by adopting a cationic regulator, then placing the ITO film in a mixed solution of sodium chloride and hydrochloric acid for presoaking treatment, then placing the ITO film in a colloidal palladium solution for activation treatment, then placing the ITO film in a chemical plating solution for electroless copper plating treatment, washing and drying, pasting a dry film on the surface of the ITO film, carrying out exposure development on the dry film by an LDI exposure machine to obtain a circuit pattern, and then carrying out electroplating copper treatment on the circuit pattern to thicken a copper layer; etching to remove copper outside the electroplated copper layer to form a desired circuit pattern; compared with the traditional silver paste printing mode, the method can avoid the generation of silver paste scraps to influence the environment and avoid the influence on the electric conversion rate of the ITO film under high-temperature baking.

Description

A photovoltaic solar N-type oxide semiconductor ITO chemical copper plating production process

Technical Field

The invention relates to the field of ITO copper plating technology, and in particular to a photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process.

Background technique

Indium Tin Oxide (ITO) is an n-type oxide semiconductor material. As a commonly used transparent conductive material, it is widely used in the field of photovoltaic solar energy due to its high conductivity, high visible light transmittance, high mechanical hardness and chemical stability.

In the prior art, the coating process of photovoltaic solar N-type oxide semiconductor ITO is generally: ITO-printed silver paste-high temperature baking (above 200°C), but high temperature baking will damage the photoelectric layer on the ITO surface, thereby reducing the electrical conversion rate of the printed silver paste layer, and the cost of the silver paste is relatively high. During the preparation process, some waste will also be generated, which has a greater impact on the environment. There are also sputtering plating processes on the market to coat photovoltaic solar N-type oxide semiconductor ITO, but this sputtering plating process has the defects of high cost, low efficiency, and high processing energy consumption, and is not suitable for the current fiercely competitive solar photovoltaic industry. In addition, if the more traditional chemical copper plating process is used to directly plate copper on the surface of the ITO film, since the surface of the ITO film is relatively smooth, it will have a greater impact on the bonding strength and formation quality of the copper plating, resulting in performance degradation.

Therefore, the prior art has defects and needs to be improved.

Summary of the invention

The technical problem to be solved by the present invention is to provide a photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process which is economical, environmentally friendly, has a high electricity conversion rate and can reduce environmental pollution.

To achieve this object, the present invention adopts the following technical solutions:

A photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process, comprising the following steps:

S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film;

S2, washing the ITO film obtained in step S1 with water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping;

S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment;

S4, washing the activated ITO film with water, and then placing it in a debonding solution for debonding treatment;

S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating;

S6, washing and drying the ITO film obtained in step S5, pasting a dry film on the surface of the ITO film, and exposing and developing the dry film with an LDI exposure machine to obtain a circuit pattern;

S7, electroplating the ITO film obtained in step S6 with copper to thicken the copper layer;

S8. Etching the ITO film to remove a portion of copper outside the electroplated copper layer to form a desired circuit pattern.

Using the above technical solution, in step S1, the surface adjustment treatment process is:

The cationic regulator is dissolved in an ethanol solvent to obtain a cationic regulator solution, and then the cationic regulator solution is evenly coated on the surface of the ITO film by spin coating, and then the ITO film coated with the cationic regulator solution is dried at a temperature of 80-140° C. and a drying time of 5-20 minutes.

According to the above technical solution, the cationic regulator is one of polyethyleneimine, polypyrrole, hexadecyltrimethylammonium bromide or tetramethylammonium salt;

When the cationic adjuster is polyethyleneimine or polypyrrole, the concentration of the cationic adjuster solution is 10-18 g/L, and the thickness of the film coated on the surface of the ITO film is 20-50 nm;

When the cationic regulator is hexadecyltrimethylammonium bromide or tetramethylammonium salt, the concentration of the cationic regulator solution is 0.1-6 g/L, and the thickness of the film coated on the surface of the ITO film is 60-100 nm.

Using the above technical solution, in step S2, the mass percentage of sodium chloride added to the mixed solution is 10-30% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 1-10% of the total solution volume, and the pre-immersion time is 1-3 minutes.

According to the technical scheme, in step S4, in step S3, the preparation process of the colloidal palladium solution is as follows: 20-40 ml/L hydrochloric acid and 30-60 ml deionized water are stirred and mixed, and then 4-6 g/L palladium chloride and 60-90 g/L sodium chloride are added in sequence, and the mixture is placed in a water bath at 45-55° C. and kept warm for 2-3 hours to obtain a colloidal palladium solution, and the activation time of the ITO film in the colloidal palladium solution is 5-20 minutes;

Alternatively, the preparation process of the colloidal palladium solution is: take 10-30 ml/L sulfuric acid and 30-60 ml deionized water, stir and mix, then add 1-3.5 g/L palladium sulfate and 60-90 g/L sodium chloride in sequence, and place in a 45-55° C. water bath for 2-3 hours.

Using the above technical solution, in step S4, the degumming solution is one of sodium carbonate solution, sodium hypochlorite solution or sulfuric acid solution, the degumming temperature is 50° C., and the degumming time is 1-5 min.

Using the above technical solution, in step S5, the temperature of the chemical plating solution is 60-75°C, and the plating time of the ITO film is 12-30 minutes;

The components and concentrations of the chemical plating solution are: copper sulfate 25-35 g/L, sodium hydroxide 8-14 g/L, formaldehyde 10-12 ml/L, EDTA 20-24 g/L, potassium sodium tartrate 8-12 g/L, stabilizer 1-1.5 g/L;

Alternatively, the components and concentrations of the chemical plating solution are: copper chloride 12-18 g/L, sodium hydroxide 6-12 g/L, formaldehyde 8-10 ml/L, EDTA 18-22 g/L, potassium sodium tartrate 6-10 g/L, and stabilizer 1-1.5 g/L.

According to the technical solution, the stabilizer is one or more of pyridine biphenyl, nickel or manganese.

Using the above technical solution, the water used in the water washing process in step S2, step S4 and step S6 is deionized water, the conductivity of the deionized water is ≤10us/cm2, and the washing time is 1-10min.

Using the above technical solution, in step S6, a film laminating machine is used to heat the dry film to 150-160°C, and then the dry film is pasted on the copper surface of the ITO film, and the pasting pressure is 2-3 kg/cm2;

In step S8, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 1-2 minutes, the etching temperature is 40-45° C., and the weight percentage of the etching solution is: 4-10% sulfuric acid, 3-6% nitric acid, 0.1-1% surfactant, and the balance is water.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention performs adjustment treatment on the surface of the ITO film by using a cationic adjusting agent before chemical copper plating on the ITO film, so as to adsorb and form a positively charged film on the surface of the ITO film, thereby enhancing the adhesion to copper ions and improving the interface contact performance; at the same time, the ITO film is pre-impregnated to increase the roughness of the surface of the ITO film, thereby increasing the adhesion of the chemical plating solution on the surface of the ITO film, and improving the uniformity and adhesion of the chemical copper plating; after the pre-impregnation, the ITO film is activated by a colloidal palladium solution to accelerate the deposition rate of catalyzing the reduction of copper ions in the chemical plating solution into solid copper, thereby improving the efficiency and quality of the chemical copper plating; In the process of chemical copper plating, the chemical plating solution used can not only improve the reduction rate and deposition rate of copper ions, but also stabilize copper ions to prevent them from reacting with other substances, thereby improving the copper plating uniformity and quality of the ITO film; in addition, the present invention adopts a chemical copper plating process to form a copper plating layer on the ITO film, which can not only avoid the generation of silver paste waste to affect the environment, but also avoid the influence on the electrical conversion rate of the ITO film under high-temperature baking above 200°C, compared with the sputtering coating process, the chemical copper plating process has the beneficial effects of low cost, high efficiency, low energy consumption, etc., and is more suitable for the current fiercely competitive solar photovoltaic industry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart showing the steps of a photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process provided by the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

Embodiment 1:

Refer to Figure 1, which is a flow chart of the steps of the photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process provided by the present invention. Embodiment 1 of the present invention provides a photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process, including the following steps:

S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film;

The cationic adjuster is polyethyleneimine, and the surface adjustment treatment process is: dissolve polyethyleneimine in an ethanol solvent to obtain a polyethyleneimine solution with a concentration of 10g/L, and then evenly apply the polyethyleneimine solution to the surface of the ITO film by spin coating to form a film layer on the surface, and the film thickness is 20nm, and then the ITO film coated with the polyethyleneimine solution is dried at a temperature of 110°C and a drying time of 5min. Cationic adjusters can adjust the charge properties of the ITO film, thereby improving its interface contact performance with other materials. Specifically, the cationic adjuster can be adsorbed on the surface of the ITO film to form a positively charged film, and this positive charge can attract the negatively charged copper ions, thereby enhancing the adhesion between the two, making the copper layer not easy to fall off, and the deposited structure more stable. In this embodiment, the drying temperature is 80°C. Note that the drying temperature cannot be too high or too low. If it is too low, it will easily lead to incomplete volatilization of the solvent, and too much solvent residue in the cationic adjuster solution will affect the uniformity and quality of the film, which is specifically manifested as uneven surface or holes in the film layer, thereby affecting the conductivity and stability of the copper layer adsorbed thereon; if it is too high, degradation or oxidation reaction will occur, resulting in a decrease in film performance or failure, and even worse, it will affect the softening or deformation of the ITO film, resulting in a decrease in the performance of the photoelectric conversion rate.

S2, washing the ITO film obtained in step S1 with deionized water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping;

The conductivity of the deionized water is ≤10us/cm2, and the washing time is 1min. In step S2, the washing is used to remove the residue of the cationic adjuster and clean the impurities and pollutants on the surface of the ITO film.

In the pre-dip treatment, the mass of sodium chloride added to the mixed solution accounts for 10% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 10% of the total solution volume, and the pre-dip time is 3 minutes. The sodium chloride and hydrochloric acid in the pre-dip solution can increase the roughness of the surface of the ITO film, thereby increasing the adhesion of the chemical plating solution on the surface of the ITO film in the subsequent process, thereby improving the uniformity and adhesion of chemical copper plating.

S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment;

The preparation process of the colloidal palladium solution is as follows: 20 ml/L hydrochloric acid and 30 ml deionized water are stirred and mixed, and then 4 g/L palladium chloride and 60 g/L sodium chloride are added in sequence, and the mixture is placed in a water bath at 45°C for 2 hours to obtain a colloidal palladium solution. The activation time of the ITO film in the colloidal palladium solution is 5 minutes. The colloidal palladium solution can be used as an activator to activate the ITO film, thereby forming a layer of active material colloidal palladium on the ITO film. The colloidal palladium has higher electron affinity and reactivity, promotes the subsequent copper plating reaction, accelerates the copper deposition process, thereby forming a good conductive layer, and improves the efficiency and quality of chemical copper plating. In this embodiment, palladium chloride, as a source of palladium ions, will be reduced to metal palladium particles. The diameter of these metal palladium particles is 20-100 nm, with a large specific surface area, which increases the contact area with other substances, has high reaction efficiency, and good catalytic performance; the role of hydrochloric acid is to provide an acidic environment to help promote the dissolution and reaction of palladium chloride; the role of sodium chloride is to provide ionic strength to help maintain the stability of the colloidal palladium particles.

S4, washing the activated ITO film with deionized water, and then placing it in a debonding solution for debonding treatment;

Among them, the water washing time is 4 minutes;

The debonding solution is a sodium carbonate solution, the debonding temperature is 50° C., and the debonding time is 3 minutes. The debonding treatment can remove the stannous ions around the colloidal palladium particles, so that the palladium core is fully exposed, thereby increasing the catalytic reaction rate of the colloidal palladium.

S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating;

The components and concentrations of the chemical plating solution are: 25 g/L copper sulfate, 8 g/L sodium hydroxide, 10 ml/L formaldehyde, 20 g/L EDTA, 8 g/L potassium sodium tartrate, and 1 g/L stabilizer;

Wherein, the stabilizer is pyridine biphenyl;

The temperature of the chemical plating solution is 60°C, and the plating time of the ITO film is 12 minutes. In this embodiment, the pH value of the chemical plating solution is 8. The role of sodium hydroxide is to adjust the pH value of the solution to keep it within an appropriate range to help control the reduction rate and deposition rate of copper ions, thereby obtaining a uniform and dense copper layer; copper sulfate is used as a copper source to provide copper ions required in the chemical plating process; formaldehyde is used as a reducing agent, which plays a role in reducing copper ions in the chemical copper plating process and promotes copper deposition; EDTA and potassium sodium tartrate are both complexing agents that can form stable complexes with copper ions to prevent copper ions from being reduced and deposited prematurely, thereby controlling the formation speed and quality of the coating; stabilizers can control the speed of chemical reactions, inhibit the deposition of impurities and the generation of bubbles, and thus improve the uniformity and quality of copper plating.

S6. After washing the ITO film obtained in step S5 with deionized water and drying it, a dry film is pasted on the surface of the ITO film, and the dry film is exposed and developed by an LDI exposure machine to obtain a circuit pattern, wherein the washing time is 5 minutes; the dry film is pasted on the surface of the ITO film that has been chemically copper-plated. The dry film is a photosensitive material that can form a specific pattern through exposure and development processes. In the LDI exposure machine, the preset pattern will be accurately transferred to the dry film, and then through the development step, the unexposed part will be removed to form a copper circuit pattern.

In the process of sticking dry film, the dry film is heated to 150°C by a film sticking machine, and then pasted on the copper surface of the ITO film, and the sticking pressure is 2kg/cm2; the film sticking machine will apply a certain pressure in the process of sticking dry film to the ITO film to ensure close contact between the dry film and the ITO film, thereby improving the sticking quality. If the pressure is too small, the dry film may not be completely stuck to the surface of the ITO film, resulting in poor sticking quality and affecting the subsequent pattern transfer effect; if the pressure is too large, the dry film or ITO film may be damaged, affecting its performance and process effect. The sticking pressure in this embodiment is 2kg/cm2, which can avoid damaging the dry film or ITO film while ensuring the tightness of the dry film and the ITO film.

S7, electroplating copper to the ITO film obtained in step S6 to thicken the copper layer, thereby improving the conductivity and durability of the circuit.

S8. Etching the ITO film to remove a portion of copper outside the electroplated copper layer to form a desired circuit pattern.

During the etching process, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 2 minutes, the etching temperature is 45°C, and the weight percentage of the etching solution is: 4% sulfuric acid, 3% nitric acid, 0.1% surfactant, and the balance is water. In this embodiment, sulfuric acid is used as an etchant to dissolve and remove the copper layer through chemical reaction; nitric acid is also a strong acid, which can also react with copper to form a soluble salt (copper nitrate), thereby helping to dissolve and remove the copper layer; in addition, nitric acid can also provide enough oxygen to enable the etching reaction to proceed more completely; the role of the surfactant is to reduce the surface tension of the solution, so that the etching solution can better wet the copper surface, thereby improving the uniformity and efficiency of etching.

Embodiment 2:

Embodiment 2 of the present invention provides a photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process, comprising the following steps:

S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film;

The cationic adjuster is polypyrrole, and the surface adjustment treatment process is: dissolving polypyrrole in an ethanol solvent to obtain a polypyrrole solution with a concentration value of 18 g/L, then uniformly coating the polypyrrole solution on the surface of the ITO film by spin coating to form a film layer on the surface with a thickness of 50 nm, and then drying the ITO film coated with the polypyrrole solution at a drying temperature of 140° C. and a drying time of 20 min.

S2, washing the ITO film obtained in step S1 with deionized water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping;

Among them, the conductivity of deionized water is ≤10us/cm2, and the washing time is 2min;

In the pre-immersion treatment, the mass percentage of sodium chloride added to the mixed solution accounts for 30% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 1% of the total solution volume, and the pre-immersion time is 3 minutes.

S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment;

The preparation process of the colloidal palladium solution is as follows: 30 ml/L sulfuric acid and 60 ml deionized water are stirred and mixed, and then 3.5 g/L palladium sulfate and 90 g/L sodium chloride are added in sequence, and the solution is placed in a water bath at 55° C. and kept warm for 3 hours to obtain a colloidal palladium solution. The activation time of the ITO film in the colloidal palladium solution is 5 minutes.

S4, washing the activated ITO film with deionized water, and then placing it in a debonding solution for debonding treatment;

Among them, the washing time is 1-10min;

The debonding solution is a hypochlorous acid solution, the debonding temperature is 50° C., and the debonding time is 5 minutes.

S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating;

The components and concentrations of the chemical plating solution are: 12 g/L copper chloride, 6 g/L sodium hydroxide, 8 ml/L formaldehyde, 18 g/L EDTA, 6 g/L potassium sodium tartrate, and 1 g/L stabilizer;

Wherein, the stabilizer is nickel;

The temperature of the chemical plating solution is 75°C, and the plating time of the ITO film is 30 minutes.

S6, washing the ITO film obtained in step S5 with deionized water and drying it, pasting a dry film on the surface of the ITO film, and exposing and developing the dry film with an LDI exposure machine to obtain a circuit pattern, wherein the washing time is 6 minutes;

In the process of sticking dry film, the dry film is heated to 160℃ by a film sticking machine and then stuck on the copper surface of the ITO film with a sticking pressure of 3 kg/cm2;

S7, electroplating the ITO film obtained in step S6 with copper to thicken the copper layer;

S8, etching the ITO film to remove copper outside the electroplated copper layer to form a desired circuit pattern;

During the etching process, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 2 minutes and the etching temperature is 40° C. The weight percentage of the etching solution is: 10% sulfuric acid, 6% nitric acid, 1% surfactant, and the balance is water.

Embodiment 3:

Embodiment 3 of the present invention provides a photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process, comprising the following steps:

S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film;

The cationic adjuster is hexadecyltrimethylammonium bromide, and the surface adjustment treatment process is: dissolving hexadecyltrimethylammonium bromide in an ethanol solvent to obtain a hexadecyltrimethylammonium bromide solution with a concentration value of 6g/L, then uniformly coating the hexadecyltrimethylammonium bromide solution on the surface of the ITO film by spin coating to form a film layer on the surface, the film layer thickness is 60nm, and then the ITO film coated with the hexadecyltrimethylammonium bromide solution is dried at a drying temperature of 80°C and a drying time of 5min.

S2, washing the ITO film obtained in step S1 with deionized water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping;

Among them, the conductivity of deionized water is ≤10us/cm2, and the washing time is 1min;

In the pre-immersion treatment, the mass percentage of sodium chloride added to the mixed solution accounts for 20% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 5% of the total solution volume, and the pre-immersion time is 2 minutes.

S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment;

The preparation process of the colloidal palladium solution is as follows: 20 ml/L sulfuric acid and 42 ml of deionized water are stirred and mixed, and then 2.5 g/L palladium sulfate and 70 g/L sodium chloride are added in sequence, and the solution is placed in a 50° C. water bath for 2 hours to obtain a colloidal palladium solution. The activation time of the ITO film in the colloidal palladium solution is 10 minutes.

S4, washing the activated ITO film with deionized water, and then placing it in a debonding solution for debonding treatment;

Among them, the water washing time is 4 minutes;

The degumming solution is a sulfuric acid solution, the degumming temperature is 50° C., and the degumming time is 2 min.

S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating;

The components and concentrations of the chemical plating solution are: 35 g/L copper sulfate, 14 g/L sodium hydroxide, 12 ml/L formaldehyde, 24 g/L EDTA, 12 g/L potassium sodium tartrate, and 1.5 g/L stabilizer;

Wherein, the stabilizer is manganese;

The temperature of the chemical plating solution is 60°C, and the plating time of the ITO film is 20 minutes.

S6, washing the ITO film obtained in step S5 with deionized water and drying it, pasting a dry film on the surface of the ITO film, and exposing and developing the dry film with an LDI exposure machine to obtain a circuit pattern, wherein the washing time is 4 minutes;

In the process of sticking dry film, the dry film is heated to 150℃ by a film sticking machine and then stuck on the copper surface of the ITO film with a sticking pressure of 2 kg/cm2;

S7, electroplating the ITO film obtained in step S6 with copper to thicken the copper layer;

S8, etching the ITO film to remove copper outside the electroplated copper layer to form a desired circuit pattern;

During the etching process, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 2 minutes and the etching temperature is 40° C. The weight percentage of the etching solution is: 6% sulfuric acid, 5% nitric acid, 0.1% surfactant, and the balance is water.

Embodiment 4:

Embodiment 4 of the present invention provides a photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process, comprising the following steps:

S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film;

The cationic adjuster is tetramethylammonium salt, and the surface adjustment treatment process is: dissolving the tetramethylammonium salt in an ethanol solvent to obtain a tetramethylammonium salt solution with a concentration value of 0.1 g/L, then uniformly coating the tetramethylammonium salt solution on the surface of the ITO film by spin coating to form a film layer on the surface, the film layer thickness is 100 nm, and then drying the ITO film coated with the tetramethylammonium salt solution, the drying temperature is 80° C., and the drying time is 5 min.

S2, washing the ITO film obtained in step S1 with deionized water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping;

Among them, the conductivity of deionized water is ≤10us/cm2, and the washing time is 3min;

In the pre-immersion treatment, the mass percentage of sodium chloride added to the mixed solution accounts for 20% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 10% of the total solution volume, and the pre-immersion time is 3 minutes.

S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment;

The preparation process of the colloidal palladium solution is as follows: 20 ml/L hydrochloric acid and 30 ml deionized water are stirred and mixed, and then 4 g/L palladium chloride and 60 g/L sodium chloride are added in sequence, and the solution is placed in a water bath at 45° C. and kept warm for 2 hours to obtain a colloidal palladium solution. The activation time of the ITO film in the colloidal palladium solution is 15 minutes.

S4, washing the activated ITO film with deionized water, and then placing it in a debonding solution for debonding treatment;

Among them, the water washing time is 2min;

The degumming solution is a sulfuric acid solution, the degumming temperature is 50° C., and the degumming time is 3 minutes.

S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating;

The components and concentrations of the chemical plating solution are: 25 g/L copper sulfate, 12 g/L sodium hydroxide, 10 ml/L formaldehyde, 22 g/L EDTA, 10 g/L potassium sodium tartrate, and 1 g/L stabilizer;

Wherein, the stabilizer is pyridine biphenyl;

The temperature of the chemical plating solution is 75°C, and the plating time of the ITO film is 18 minutes.

S6, washing the ITO film obtained in step S5 with deionized water and drying it, pasting a dry film on the surface of the ITO film, and exposing and developing the dry film with an LDI exposure machine to obtain a circuit pattern, wherein the washing time is 1-10 minutes;

In the process of sticking dry film, the dry film is heated to 160℃ by a film sticking machine and then stuck on the copper surface of the ITO film with a sticking pressure of 2 kg/cm2;

S7, electroplating the ITO film obtained in step S6 with copper to thicken the copper layer;

S8, etching the ITO film to remove copper outside the electroplated copper layer to form a desired circuit pattern;

During the etching process, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 1 minute and the etching temperature is 45° C. The weight percentage of the etching solution is: 4% sulfuric acid, 4% nitric acid, 0.1% surfactant, and the balance is water.

Comparative Example 1:

The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 1 is different from that of Example 1 in that:

The cationic adjusting agent is not used to perform surface adjustment treatment on the ITO film, that is, step S1 is missing.

Comparative Example 2:

The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 2 is different from that of Example 1 in that:

The ITO film is not pre-impregnated, that is, step S2 is missing.

Comparative Example 3:

The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 3 is different from that of Example 1 in that:

In step S5, the components and concentrations of the chemical plating solution are: 25 g/L copper sulfate, 8 g/L sodium hydroxide, 10 ml/L formaldehyde, and 1 g/L stabilizer, that is, the components EDTA and sodium potassium tartrate are missing.

Comparative Example 4:

The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 4 is different from that of Example 1 in that:

In step S1, the drying temperature is 200°C.

Comparative Example 5:

The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 5 is different from that of Example 1 in that:

In step S1, the drying temperature is 70°C.

Comparative Example 6:

The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 6 is different from that of Example 1 in that:

In step S5, the temperature of the chemical plating solution is 50°C.

Comparative Example 7:

The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process of this comparative example 7 is different from that of Example 1 in that:

In step S1 , the temperature of the chemical plating solution is 100° C.

The following experiments are conducted on the above-mentioned embodiments 1-4 and comparative examples 1-7 to verify or understand their performances.

Experiment 1: Determination of copper plating morphology:

In the ITO thin film copper coatings obtained in the above Examples 1-4 and Comparative Examples 1-7, the surface morphology of the copper coatings was measured using a metallographic microscope, and the cross-section of the copper coating was observed and measured using a SEM.

Table 1, Comparison of copper plating morphology of various embodiments and comparative examples:

According to Table 1 above:

The copper coatings of Examples 1-4 have smooth surfaces, no dark holes or cracks, and the cross-section coatings are uniform and dense, indicating that the copper coatings of the ITO films prepared by the present invention are of good quality; Comparative Example 1 does not perform surface conditioning treatment on the ITO film, indicating that the cationic conditioning agent can enhance the adhesion between the ITO film and the copper coating, and has a certain effect on improving the quality of the copper coating; Comparative Example 2 does not perform pre-preg treatment on the ITO film, indicating that the mixed solution of sodium chloride and hydrochloric acid can affect the adhesion of the ITO film surface, thereby affecting the quality of the copper coating attached to the surface; the chemical plating solution components of Comparative Example 3 lack E DTA and potassium sodium tartrate indicate that EDTA and potassium sodium tartrate can form a stable complex with copper ions, thereby controlling the formation quality of the copper plating layer; the drying temperature in step S1 of comparative example 4 is 200°C, indicating that too high a temperature has no effect on the quality formation of the copper plating layer; the drying temperature in step S1 of comparative example 5 is 70°C, indicating that too low a temperature will have a greater effect on the quality formation of the copper plating layer; the chemical plating solution temperature of comparative example 6 is 50°C, and the chemical plating solution temperature of comparative example 7 is 100°C, indicating that too high or too low a temperature of the chemical plating solution will have a certain effect on the formation quality of the copper plating layer.

Experiment 2: Determination of copper plating bonding strength:

In the ITO thin film copper plating obtained in the above Examples 1-4 and Comparative Examples 1-7, the plating bonding strength was measured on a 100kg-level spring testing machine.

Table 2, comparison table of copper plating bonding strength test of each embodiment and comparative example:

According to Table 2 above, we can know that:

Compared with comparative examples 1-7, in Example 1-4, the ITO thin film copper plating layer prepared by the present invention has better bonding force with the ITO thin film, and the copper plating layer structure is more stable and not easy to fall off.

In summary, before the ITO film is subjected to chemical copper plating, the surface of the ITO film is adjusted by a cationic adjusting agent to adsorb and form a positively charged film on the surface of the ITO film, thereby enhancing the adhesion to copper ions and improving the interface contact performance; at the same time, the ITO film is subjected to a pre-impregnation treatment to increase the roughness of the surface of the ITO film, thereby increasing the adhesion of the chemical plating solution on the surface of the ITO film, and improving the uniformity and adhesion of the chemical copper plating; after the pre-impregnation treatment, the ITO film is activated by a colloidal palladium solution to accelerate the catalytic reduction of copper ions in the chemical plating solution. The deposition rate of solid copper is increased, thereby improving the efficiency and quality of chemical copper plating; in the process of chemical copper plating on the ITO film, the chemical plating solution used can not only increase the reduction rate and deposition speed of copper ions, but also stabilize the copper ions to prevent them from reacting with other substances, thereby improving the copper plating uniformity and quality of the ITO film; in addition, the present invention adopts a chemical copper plating process to form a copper plating layer on the ITO film, compared with the traditional silver paste printing method, not only can the generation of silver paste waste to affect the environment, but also can avoid the influence on the electrical conversion rate of the ITO film under high-temperature baking above 200°C.

The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process, characterized in that it includes the following steps: S1. Using a cationic adjuster to perform surface adjustment treatment on the ITO film; S2, washing the ITO film obtained in step S1 with water, and then placing it in a mixed solution of sodium chloride and hydrochloric acid for pre-dipping; S3, placing the pre-impregnated ITO film in a colloidal palladium solution for activation treatment; S4, washing the activated ITO film with water, and then placing it in a debonding solution for debonding treatment; S5, placing the debonded ITO film in a chemical plating solution for chemical copper plating; S6, washing and drying the ITO film obtained in step S5, pasting a dry film on the surface of the ITO film, and exposing and developing the dry film with an LDI exposure machine to obtain a circuit pattern; S7, electroplating the ITO film obtained in step S6 with copper to thicken the copper layer; S8. Etching the ITO film to remove a portion of copper outside the electroplated copper layer to form a desired circuit pattern. 2. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1, characterized in that in step S1, the surface adjustment treatment process is: The cationic regulator is dissolved in an ethanol solvent to obtain a cationic regulator solution, and then the cationic regulator solution is evenly coated on the surface of the ITO film by spin coating, and then the ITO film coated with the cationic regulator solution is dried at a temperature of 80-140° C. and a drying time of 5-20 minutes. 3. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 2, characterized in that the cationic regulator is one of polyethyleneimine, polypyrrole, hexadecyltrimethylammonium bromide or tetramethylammonium salt; When the cationic adjuster is polyethyleneimine or polypyrrole, the concentration of the cationic adjuster solution is 10-18 g/L, and the thickness of the film coated on the surface of the ITO film is 20-50 nm; When the cationic regulator is hexadecyltrimethylammonium bromide or tetramethylammonium salt, the concentration of the cationic regulator solution is 0.1-6 g/L, and the thickness of the film coated on the surface of the ITO film is 60-100 nm. 4. The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating production process according to claim 1 is characterized in that, in step S2, the mass percentage of sodium chloride added to the mixed solution is 10-30% of the total solution volume, the concentration of the added hydrochloric acid solution is 37%, and its volume accounts for 1-10% of the total solution volume, and the pre-immersion time is 1-3min. 5. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1, characterized in that in step S3, the preparation process of the colloidal palladium solution is: take 20-40ml/L hydrochloric acid and 30-60ml deionized water and stir and mix, then add 4-6g/L palladium chloride and 60-90g/L sodium chloride in sequence, and place in a 45-55°C water bath for 2-3h to obtain a colloidal palladium solution, and the activation time of the ITO film in the colloidal palladium solution is 5-20min; Alternatively, the preparation process of the colloidal palladium solution is: take 10-30 ml/L sulfuric acid and 30-60 ml deionized water, stir and mix, then add 1-3.5 g/L palladium sulfate and 60-90 g/L sodium chloride in sequence, and place in a 45-55° C. water bath for 2-3 hours. 6. The photovoltaic solar N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1 is characterized in that in step S4, the degumming solution is one of sodium carbonate solution, sodium hypochlorite solution or sulfuric acid solution, the degumming temperature is 50° C., and the degumming time is 1-5 min. 7. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1, characterized in that in step S5, the temperature of the chemical plating solution is 60-75° C., and the plating time of the ITO film is 12-30 minutes; The components and concentrations of the chemical plating solution are: copper sulfate 25-35 g/L, sodium hydroxide 8-14 g/L, formaldehyde 10-12 ml/L, EDTA 20-24 g/L, potassium sodium tartrate 8-12 g/L, stabilizer 1-1.5 g/L; Alternatively, the components and concentrations of the chemical plating solution are: copper chloride 12-18 g/L, sodium hydroxide 6-12 g/L, formaldehyde 8-10 ml/L, EDTA 18-22 g/L, potassium sodium tartrate 6-10 g/L, and stabilizer 1-1.5 g/L. 8 . The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 7 , characterized in that the stabilizer is one or more of pyridine biphenyl, nickel or manganese. 9. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1 is characterized in that the water used in the water washing process in step S2, step S4 and step S6 is deionized water, the conductivity of the deionized water is ≤10us/cm2, and the washing time is 1-10min. 10. The photovoltaic solar energy N-type oxide semiconductor ITO chemical copper plating manufacturing process according to claim 1, characterized in that in step S6, a film laminating machine is used to heat the dry film to 150-160° C. and then paste it on the copper surface of the ITO film, and the pasting pressure is 2-3 kg/cm2; In step S8, an etching solution is used to etch the copper layer outside the circuit pattern on the ITO film. The etching time is 1-2 minutes, the etching temperature is 40-45° C., and the weight percentage of the etching solution is: 4-10% sulfuric acid, 3-6% nitric acid, 0.1-1% surfactant, and the balance is water.