Method for goldizing a glass substrate

Abstract

The application relates to the technical field of circuit board surface treatment, and provides a gold plating method for a glass substrate, which comprises the following steps: providing a glass substrate with a surface provided with circuit arrangement, and performing mask processing on the surface of the glass substrate and exposing the circuit to be plated; sequentially performing plasma cleaning and dirt removal processing, micro-etching processing, acid pickling processing, pre-impregnation processing, activation processing, post-impregnation processing, nickel plating processing and gold plating processing on the circuit to be plated. The gold plating method uses plasma to perform cleaning and dirt removal processing, and combines acid pickling processing, pre-impregnation processing and post-impregnation processing to synergistically cooperate, so as to ensure that the surface of the circuit to be plated is clean and has reaction activity, effectively avoids the problem that the glass substrate is broken in the cleaning and dirt removal processing by using an alkaline cleaning agent in the traditional technology, and makes the thickness uniformity of the film layer formed by gold plating of the glass substrate good and the adhesion stable.

Description

Technical Field

[0001] This application relates to the field of circuit board surface treatment technology, and in particular to a method for electroplating glass substrates. Background Technology

[0002] Glass substrates are a key material in the semiconductor industry. Compared to traditional PCBs (Printed Circuit Boards), glass substrates offer superior thermal stability, excellent electrical performance, high flatness, and good light transmittance. Traditionally, a gold layer can be formed on the copper layer of a PCB using an electroless gold plating process to further improve the stability of circuit connections. However, due to the difference in thermal expansion coefficient and material composition between glass substrates and PCBs, and the more intricate circuitry on glass substrates, directly processing them using traditional PCB electroless gold plating processes can easily lead to problems such as film peeling and uneven thickness, resulting in poor circuit connection stability. Summary of the Invention

[0003] Therefore, it is necessary to provide a method for electroplating glass substrates to realize the electroplating process of glass substrates and improve the stability of circuit connections on glass substrates.

[0004] This application provides a method for gold plating on a glass substrate, comprising the following steps:

[0005] A glass substrate with a circuit layout on its surface is provided, and the surface of the glass substrate is masked to expose the circuit to be plated.

[0006] Plasma is used to clean and decontaminate the surface of the circuit to be plated, in order to remove organic dirt from the surface of the circuit to be plated.

[0007] The surface of the circuit to be plated is micro-etched using a micro-etching solution after cleaning and decontamination.

[0008] The circuit to be plated after micro-etching is pickled with a first acidic solution, and then pre-immersed with a second acidic solution to clean the surface of the circuit to be plated and make the surface of the circuit to be plated active.

[0009] The pre-immersion treated circuit is activated by a plating solution containing a palladium source to form active palladium on the surface of the circuit.

[0010] The activated circuit board is then immersed in a third acidic solution to clean the surface of the circuit board again and activate its surface.

[0011] The circuit to be plated after immersion is treated with a nickel-plating solution, which includes a nickel source and a phosphorus source, to form a phosphorus-nickel alloy layer on the surface of the circuit to be plated.

[0012] A gold plating solution is used to perform a gold plating treatment on the circuit to be plated after nickel plating, so as to form a gold layer on the surface of the phosphorus-nickel alloy layer.

[0013] In some implementations, the cleaning and decontamination treatment satisfies at least one of the following conditions:

[0014] (1) The plasma used for cleaning and decontamination treatment includes oxygen or argon;

[0015] (2) The power of the plasma during the cleaning and decontamination process is 1500W~3000W.

[0016] In some embodiments, the micro-etching solution contains sodium persulfate and sulfuric acid.

[0017] Optionally, the mass concentration of sodium persulfate in the micro-etching solution is 20 g / L to 80 g / L.

[0018] Optionally, the sulfuric acid in the micro-etching solution has a volume concentration of 10 mL / L to 50 mL / L.

[0019] In some embodiments, the first acidic solution, the second acidic solution, and the third acidic solution each independently comprise sulfuric acid.

[0020] In some embodiments, the gold plating method for the glass substrate satisfies at least one of the following conditions:

[0021] (1) The volume concentration of sulfuric acid in the first acidic solution is 30 mL / L to 70 mL / L;

[0022] (2) The volume concentration of sulfuric acid in the second acidic solution is 10 mL / L to 30 mL / L;

[0023] (3) The volume concentration of sulfuric acid in the third acidic solution is 20 mL / L to 80 mL / L.

[0024] In some embodiments, the plating solution in the activation treatment satisfies at least one of the following conditions:

[0025] (1) The mass concentration of palladium source in the plating solution is 6 ppm to 20 ppm;

[0026] (2) The palladium source includes at least one of palladium chloride and palladium sulfate;

[0027] (3) The plating solution also contains sulfuric acid, and the volume concentration of sulfuric acid in the plating solution is 10 mL / L to 30 mL / L.

[0028] In some embodiments, the nickel plating treatment satisfies at least one of the following conditions:

[0029] (1) The pH value of the nickel melting solution is 3~6 during the nickel melting process;

[0030] (2) The temperature of the nickel melting solution during the nickel melting process is 60℃~80℃.

[0031] In some embodiments, the nickel plating solution satisfies at least one of the following conditions:

[0032] (1) The mass concentration of nickel ions in the nickel oxide solution is 4 g / L to 6 g / L;

[0033] (2) The mass concentration of phosphorus source in the nickel chloride solution is 10 g / L to 40 g / L;

[0034] (3) The nickel source contained in the nickel sulfate solution includes nickel sulfate;

[0035] (5) The phosphorus source contained in the nickel solution includes sodium hypophosphite.

[0036] In some implementations, the gold plating process satisfies at least one of the following conditions:

[0037] (1) The pH value of the gold-plating solution during the gold plating process is 4~6;

[0038] (2) The temperature of the gold solution during the gold treatment process is 70℃~90℃.

[0039] In some embodiments, the gold-plating solution satisfies at least one of the following conditions:

[0040] (1) The concentration of gold ions in the gold-containing solution is 0.5 g / L to 1.5 g / L;

[0041] (2) The gold-plating solution also contains citric acid, and the mass concentration of citric acid in the gold-plating solution is 5 g / L to 10 g / L;

[0042] (3) The gold source contained in the gold solution includes potassium gold cyanide.

[0043] Compared with traditional technologies, this application has at least the following beneficial effects:

[0044] The gold plating method for this glass substrate employs plasma cleaning and decontamination treatment, avoiding the use of alkaline cleaning agents for immersion degreasing and reducing the risk of glass substrate breakage. Furthermore, the combination of acidic solutions in pickling, pre-immersion, and post-immersion treatments ensures surface activity before nickel plating, improves the adhesion stability of the gold plating portion, and results in good film thickness uniformity. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments and examples of this application, and to more completely understand this application and its beneficial effects, the accompanying drawings used in the description of the embodiments or examples will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of this application. Those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0046] Figure 1 This is a schematic flowchart of a method for gold plating on a glass substrate according to one embodiment. Detailed Implementation

[0047] The present application will be further described in detail below with reference to the embodiments and examples. These embodiments and examples are only for illustrating the present application and are not intended to limit the scope of the present application. The purpose of providing these embodiments and examples is to make the disclosure of the present application more thorough and comprehensive. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or alterations without departing from the spirit of the present application, and the equivalent forms obtained also fall within the protection scope of the present application. In addition, numerous specific details are set forth in the following description to provide a fuller understanding of the present application. It should be understood that the present application can be implemented without one or more of these details.

[0048] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0049] In this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on quantity.

[0050] Chemical gold plating is a chemical displacement reaction primarily used for surface treatment of PCBs. The principle involves chemically depositing a 3μm~5μm thick nickel-phosphorus alloy layer onto the copper surface of the PCB, followed by depositing a 0.025μm~0.15μm thick gold layer onto the nickel-phosphorus alloy layer using gold salts. Due to gold's extremely high chemical stability, electrical conductivity, thermal conductivity, and infrared reflectivity, it effectively protects easily oxidized metal layers such as copper and aluminum, achieving stable conductivity and heat dissipation, reducing electromagnetic interference, and promoting efficient signal transmission, making it suitable for high-frequency and high-speed devices. Furthermore, the gold layer provides a uniform and clean surface during device wire bonding, improving bonding strength and yield.

[0051] However, in traditional PCB plating processes, alkaline cleaning agents are first used to degrease the circuitry, followed by micro-etching and activation to improve the cleanliness and surface activity of the circuitry, thereby enhancing the uniformity and stability of the formed film thickness. But when this method is used on glass substrates, the alkaline cleaning agents can easily cause the glass substrate to break, resulting in a film thickness that does not meet usage requirements or even peeling off. Furthermore, defects such as incomplete plating, over-plating, and blackening can occur. Traditional methods cannot meet the requirements for plating on glass substrates.

[0052] Based on this, this application provides a method for gold plating on a glass substrate, as exemplarily described in the following reference. Figure 1 This includes the following steps:

[0053] A glass substrate with a circuit layout on its surface is provided, and the surface of the glass substrate is masked to expose the circuit to be plated.

[0054] Plasma is used to clean and decontaminate the surface of the circuit to be plated, in order to remove organic dirt from the surface of the circuit to be plated.

[0055] The surface of the circuit to be plated is micro-etched using a micro-etching solution after cleaning and decontamination.

[0056] The circuit to be plated after micro-etching is pickled with a first acidic solution, and then pre-immersed with a second acidic solution to clean the surface of the circuit to be plated and make the surface of the circuit to be plated active.

[0057] The pre-immersion treated circuit is activated by a plating solution containing a palladium source to form active palladium on the surface of the circuit.

[0058] The activated circuit board is then immersed in a third acidic solution to clean the surface of the circuit board again and activate its surface.

[0059] The circuit to be plated after immersion is treated with a nickel-plating solution, which includes a nickel source and a phosphorus source, to form a phosphorus-nickel alloy layer on the surface of the circuit to be plated.

[0060] A gold plating solution is used to perform a gold plating treatment on the circuit to be plated after nickel plating, so as to form a gold layer on the surface of the phosphorus-nickel alloy layer.

[0061] During the masking process, photoresist can be applied to the surface of a glass substrate, thereby exposing the areas that need to be gold-plated through exposure and development.

[0062] The gold plating method for this glass substrate employs plasma cleaning to remove contaminants, avoiding the use of alkaline cleaning agents for degreasing and reducing the risk of glass substrate breakage due to immersion. Furthermore, the use of acidic solutions in the pickling, pre-immersion, and post-immersion processes ensures surface activity before nickel plating, improving the adhesion stability of the gold plating portion and resulting in good film thickness uniformity.

[0063] Plasma cleaning utilizes high-energy plasma particles to bombard the surface of the circuit board to be plated, thereby removing organic dirt and grime. Understandably, the appropriate cleaning and decontamination time can be selected based on the degree of cleanliness and decontamination required.

[0064] In some embodiments, the plasma used in the cleaning and decontamination process includes oxygen or argon.

[0065] In some embodiments, the power of the plasma during the cleaning and decontamination process is 1500W to 3000W, for example, it can be 1500W, 1800W, 2100W, 2400W, 2700W or 3000W.

[0066] This cleaning and decontamination treatment uses the plasma and power parameters mentioned above, which can effectively clean organic dirt on the surface, thereby avoiding the problems that may occur in traditional technologies, such as incomplete cleaning or the introduction of new dirt, or even substrate breakage, caused by soaking the substrate in alkaline cleaning solution.

[0067] In some embodiments, the micro-etching solution contains sodium persulfate and sulfuric acid. Optionally, the mass concentration of sodium persulfate in the micro-etching solution is 20 g / L to 80 g / L, for example, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, 50 g / L, 55 g / L, 60 g / L, 65 g / L, 70 g / L, 75 g / L, or 80 g / L. Optionally, the volume concentration of sulfuric acid in the micro-etching solution is 10 mL / L to 50 mL / L, for example, 10 mL / L, 15 mL / L, 20 mL / L, 25 mL / L, 30 mL / L, 35 mL / L, 40 mL / L, 45 mL / L, or 50 mL / L. It is understood that the appropriate micro-etching time can be selected according to the degree of micro-etching of the circuit to be plated.

[0068] This micro-etching process uses the above micro-etching solution to micro-etch the circuit surface, thereby improving the adhesion of the gold-plated film.

[0069] In some embodiments, the first acidic solution includes sulfuric acid. Optionally, the volume concentration of sulfuric acid in the first acidic solution is 30 mL / L to 70 mL / L, for example, 30 mL / L, 35 mL / L, 40 mL / L, 45 mL / L, 50 mL / L, 55 mL / L, 60 mL / L, 65 mL / L, or 70 mL / L. It is understood that the appropriate pickling time can be selected according to the degree of cleaning required for the circuit to be plated. This pickling treatment using the aforementioned first acidic solution can further remove grease and organic matter from the circuit surface, improving surface cleanliness.

[0070] In some embodiments, the second acidic solution comprises sulfuric acid. Optionally, the volume concentration of sulfuric acid in the second acidic solution is 10 mL / L to 30 mL / L, for example, it can be 10 mL / L, 12 mL / L, 14 mL / L, 16 mL / L, 18 mL / L, 20 mL / L, 22 mL / L, 24 mL / L, 26 mL / L, 28 mL / L, or 30 mL / L. It is understood that an appropriate pre-immersion treatment time can be selected based on the surface condition of the circuit to be plated. This pre-immersion treatment using the aforementioned second acidic solution can keep the circuit surface clean and improve the surface activity of the circuit.

[0071] In some embodiments, the mass concentration of the palladium source in the plating solution is 6ppm to 20ppm, for example, it can be 6ppm, 8ppm, 10ppm, 12ppm, 14ppm, 16ppm, 18ppm or 20ppm.

[0072] In some embodiments, the palladium source includes at least one of palladium chloride and palladium sulfate.

[0073] In some embodiments, the plating solution also contains sulfuric acid, and the volume concentration of sulfuric acid in the plating solution is 10 mL / L to 30 mL / L, for example, it can be 10 mL / L, 12 mL / L, 14 mL / L, 16 mL / L, 18 mL / L, 20 mL / L, 22 mL / L, 24 mL / L, 26 mL / L, 28 mL / L or 30 mL / L.

[0074] The activation treatment uses the plating solution described above, which can form activated palladium on the circuit surface, thus acting as a catalytic medium for nickel plating and improving the effectiveness of the nickel plating process. Understandably, the appropriate activation time can be selected based on the activation requirements.

[0075] In some embodiments, the third acidic solution includes sulfuric acid. Optionally, the volume concentration of sulfuric acid in the third acidic solution is 20 mL / L to 80 mL / L, for example, it can be 20 mL / L, 25 mL / L, 30 mL / L, 35 mL / L, 40 mL / L, 45 mL / L, 50 mL / L, 55 mL / L, 60 mL / L, 65 mL / L, 70 mL / L, 75 mL / L, or 80 mL / L. It is understood that an appropriate post-immersion treatment time can be selected based on the surface condition of the circuit to be plated.

[0076] This pickling process uses the aforementioned third acidic solution to maintain the surface activity of the circuitry to be plated after activation treatment. This compensates for the low surface activity caused by not using an alkaline cleaning agent for degreasing, ensuring the smooth progress of the nickel plating process and avoiding defects such as incomplete plating, seepage, poor adhesion, and blackening. If the volume concentration of sulfuric acid in the third acidic solution is relatively low, insufficient activity may lead to problems such as incomplete plating and poor adhesion; conversely, if the volume concentration of sulfuric acid in the third acidic solution is relatively high, relatively high activity may lead to problems such as seepage and blackening.

[0077] In some embodiments, the pH value of the nickel plating solution during the nickel plating process is 3 to 6, for example, it can be 3.0, 3.5, 4.0, 4.5, 5.0, 5.5 or 6.0.

[0078] In some embodiments, the temperature of the nickel melting solution during the nickel melting process is 60°C to 80°C, for example, it can be 60°C, 62°C, 64°C, 66°C, 68°C, 70°C, 72°C, 74°C, 76°C, 78°C or 80°C.

[0079] In some embodiments, the mass concentration of nickel ions in the nickel oxide solution is 4 g / L to 6 g / L, for example, it can be 4.0 g / L, 4.2 g / L, 4.4 g / L, 4.6 g / L, 4.8 g / L, 5.0 g / L, 5.2 g / L, 5.4 g / L, 5.6 g / L, 5.8 g / L or 6.0 g / L.

[0080] In some embodiments, the mass concentration of the phosphorus source contained in the nickel oxide solution is 10 g / L to 40 g / L, for example, it can be 10 g / L, 13 g / L, 16 g / L, 19 g / L, 22 g / L, 25 g / L, 28 g / L, 31 g / L, 34 g / L, 37 g / L or 40 g / L.

[0081] In some embodiments, the nickel source contained in the nickel oxide solution includes nickel sulfate.

[0082] In some embodiments, the phosphorus source contained in the nickel hydroxide solution includes sodium hypophosphite.

[0083] Understandably, the appropriate nickel plating time can be selected based on the thickness of the phosphorus-nickel alloy layer.

[0084] In some embodiments, the pH value of the gold chemiluminescence solution during the gold chemiluminescence treatment is 4 to 6, for example, it can be 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8 or 6.0.

[0085] In some embodiments, the temperature of the gold-plating solution during the gold plating process is 70°C to 90°C, for example, it can be 70°C, 72°C, 74°C, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C, 88°C or 90°C.

[0086] In some embodiments, the concentration of gold ions in the gold-containing solution is 0.5 g / L to 1.5 g / L, for example, it can be 0.5 g / L, 0.6 g / L, 0.7 g / L, 0.8 g / L, 0.9 g / L, 1.0 g / L, 1.1 g / L, 1.2 g / L, 1.3 g / L, 1.4 g / L or 1.5 g / L.

[0087] In some embodiments, the gold plating solution further contains citric acid. Optionally, the mass concentration of citric acid in the gold plating solution is 5 g / L to 10 g / L, for example, it can be 5.0 g / L, 5.5 g / L, 6.0 g / L, 6.5 g / L, 7.0 g / L, 7.5 g / L, 8.0 g / L, 8.5 g / L, 9.0 g / L, 9.5 g / L, or 10.0 g / L;

[0088] In some embodiments, the gold source contained in the gold-containing solution includes potassium gold cyanide.

[0089] Understandably, the appropriate gold plating time can be selected based on the thickness of the gold layer.

[0090] In some embodiments, the material of the circuitry on the glass substrate may be copper.

[0091] Optionally, the linewidth of the circuit is 10μm to 65μm, for example, it can be 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, 60μm or 65μm. The thickness of the circuit is 800nm ​​to 2μm, for example, it can be 800nm, 1.0μm, 1.2μm, 1.4μm, 1.6μm or 2.0μm.

[0092] In some embodiments, a nickel-phosphorus alloy layer and a gold layer are formed on the surface of the circuit to be plated on the glass substrate after electroless gold plating. Optionally, the thickness of the nickel-phosphorus alloy layer is 1.5 μm to 2.5 μm, for example, 1.5 μm, 2.0 μm, or 2.5 μm. The thickness of the gold layer is 50 nm to 80 nm, for example, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, or 80 nm.

[0093] The embodiments of this application will be described in detail below with reference to examples. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of this application. For experimental methods in the following embodiments where specific conditions are not specified, please refer to the guidelines given in this application, or follow experimental manuals or conventional conditions in the art, or follow the conditions recommended by the manufacturer, or refer to experimental methods known in the art.

[0094] Example 1

[0095] A glass substrate is provided, the surface of which has copper lines with a thickness of 1.2 μm and a width of 15 μm. Photoresist is coated on the surface of the glass substrate and exposed and developed to reveal the lines to be plated.

[0096] The surface of the circuit to be plated is cleaned and decontaminated for 50 seconds using plasma to remove organic dirt. The plasma used for cleaning and decontamination is oxygen and has a power of 2000W.

[0097] The surface of the circuit to be plated after cleaning and decontamination was micro-etched for 10 seconds using a micro-etching solution; the mass concentration of sodium persulfate in the micro-etching solution was 50 g / L, and the volume concentration of sulfuric acid was 30 mL / L.

[0098] The circuit to be plated after micro-etching was pickled for 30 seconds using a sulfuric acid solution with a volume concentration of 50 mL / L; then the circuit to be plated was pre-immersed in a sulfuric acid solution with a volume concentration of 20 mL / L for 60 seconds to clean the surface of the circuit to be plated and make the surface of the circuit to be plated active.

[0099] The pre-immersion treated circuitry was activated for 60 seconds using a plating solution to form active palladium on its surface. The plating solution contained palladium chloride at a mass concentration of 13 ppm and sulfuric acid at a volume concentration of 20 mL / L.

[0100] The activated circuit to be plated was subjected to a post-immersion treatment of 30s using a sulfuric acid solution with a volume concentration of 50mL / L, in order to clean the surface of the circuit to be plated again and make the surface of the circuit to be plated active.

[0101] The circuit to be plated was subjected to nickel plating treatment at 70°C for 11 minutes using a nickel plating solution to form a nickel-phosphorus alloy layer on the surface of the circuit. Nickel sulfate was used as the nickel source in the nickel plating solution, with a nickel ion concentration of 5 g / L. Sodium hypophosphite was used as the phosphorus source in the nickel plating solution, with a sodium hypophosphite concentration of 25 g / L. The pH value of the nickel plating solution was maintained between 3 and 6 during the nickel plating process.

[0102] The circuit to be plated after nickel plating was subjected to a gold plating solution at 80°C for 12.5 minutes to form a gold layer on the surface of the nickel-phosphorus alloy layer. The gold plating solution contained potassium gold cyanide and citric acid. The concentration of gold ions in the gold plating solution was 1 g / L, and the concentration of citric acid in the gold plating solution was 7 g / L. During the gold plating process, the pH value of the gold plating solution was between 4 and 6.

[0103] Comparative Example 1

[0104] The gold plating method for the glass substrate was similar to that in Example 1, except that the cleaning and decontamination treatment involved immersion in a NaOH solution with a mass concentration of 13 g / L.

[0105] Comparative Example 2

[0106] The same gold plating method for glass substrates as in Example 1 is used, except that acid washing and pre-immersion treatment are not performed.

[0107] Comparative Example 3

[0108] The same gold plating method for glass substrates as in Example 1 is used, except that no post-immersion treatment is performed.

[0109] The glass substrates obtained by gold plating in the above embodiments and comparative embodiments were subjected to performance tests, and the test methods included:

[0110] Film thickness testing: The total thickness of the phosphorus-nickel alloy layer and the gold layer in the gold-plated area was measured using a fluorescence film thickness gauge.

[0111] Adhesion test: Use 3M tape to pull the electroplated metal circuit section. If there is no peeling, it is marked as OK. If it peels off partially or completely, it is marked as NG.

[0112] Appearance: Observe whether there are foreign objects, blackening, incomplete plating or over-plating, or other defects in the electroless gold coating.

[0113] The test results are shown in Table 1.

[0114] Table 1

[0115]

[0116] As shown in the table above, in Comparative Example 1, immersing the glass substrate in an alkaline cleaning solution for degreasing easily leads to breakage. Furthermore, alkaline degreasing is unsuitable for the pre-gold plating process of the glass substrate, resulting in poor adhesion of the film layer. Slight peeling occurs when using 3M tape, and foreign matter bumps are visible in the gold-plated area, indicating incomplete cleaning. In Comparative Example 2, no acid washing or pre-immersion treatment was used, resulting in incomplete cleaning of the glass substrate before gold plating. This means that existing dirt or oxidation points on the glass substrate remain after gold plating, and the activity of the area to be gold-plated is poor, leading to poor film adhesion. The film layer detaches completely when using 3M tape. In Comparative Example 3, no post-immersion treatment was used, resulting in poor activity of the glass substrate before gold plating. Slight film layer detachment occurs when using 3M tape. Additionally, the lack of a post-immersion treatment results in incomplete cleaning of the glass substrate, leading to defects such as blackening of foreign matter after gold plating. However, the adhesion of Comparative Example 3 is slightly better than that of Comparative Example 2.

[0117] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0118] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A method for gold plating on a glass substrate, characterized in that, Includes the following steps: A glass substrate with a circuit layout on its surface is provided, and the surface of the glass substrate is masked to expose the circuit to be plated. Plasma is used to clean and decontaminate the surface of the circuit to be plated, in order to remove organic dirt from the surface of the circuit to be plated. The surface of the circuit to be plated is micro-etched using a micro-etching solution after cleaning and decontamination treatment. The circuit to be plated after micro-etching is pickled with a first acidic solution, and then the circuit to be plated is pre-immersed with a second acidic solution to clean the surface of the circuit to be plated and make the surface of the circuit to be plated active. The circuit to be plated after pre-immersion treatment is activated by a plating solution containing a palladium source to form active palladium on the surface of the circuit to be plated. The activated circuit is then immersed in a third acidic solution to clean the surface of the circuit again and activate it. The circuit to be plated is subjected to nickel plating treatment using a nickel plating solution, which includes a nickel source and a phosphorus source, to form a phosphorus-nickel alloy layer on the surface of the circuit to be plated. The circuit to be plated is subjected to electroless gold treatment using an electroless gold solution to form a gold layer on the surface of the phosphorus-nickel alloy layer.

2. The method for gold plating on a glass substrate as described in claim 1, characterized in that, The cleaning and decontamination treatment meets at least one of the following conditions: (1) The plasma used in the cleaning and decontamination treatment includes oxygen or argon; (2) The power of the plasma during the cleaning and decontamination process is 1500W~3000W.

3. The method for gold plating on a glass substrate as described in claim 1, characterized in that, The micro-etching solution contains sodium persulfate and sulfuric acid; Optionally, the mass concentration of sodium persulfate in the micro-etching solution is 20 g / L to 80 g / L; Optionally, the sulfuric acid in the micro-etching solution has a volume concentration of 10 mL / L to 50 mL / L.

4. The method for gold plating on a glass substrate as described in claim 1, characterized in that, The first acidic solution, the second acidic solution, and the third acidic solution each independently comprise sulfuric acid.

5. The method for gold plating on a glass substrate as described in claim 4, characterized in that, The gold plating method for the glass substrate satisfies at least one of the following conditions: (1) The volume concentration of sulfuric acid in the first acidic solution is 30 mL / L to 70 mL / L; (2) The volume concentration of sulfuric acid in the second acidic solution is 10 mL / L to 30 mL / L; (3) The volume concentration of sulfuric acid in the third acidic solution is 20 mL / L to 80 mL / L.

6. The method for gold plating of a glass substrate as described in any one of claims 1-5, characterized in that, The plating solution in the activation treatment satisfies at least one of the following conditions: (1) The mass concentration of the palladium source in the plating solution is 6 ppm to 20 ppm; (2) The palladium source includes at least one of palladium chloride and palladium sulfate; (3) The plating solution also contains sulfuric acid, and the volume concentration of sulfuric acid in the plating solution is 10 mL / L to 30 mL / L.

7. The method for gold plating of a glass substrate as described in any one of claims 1-5, characterized in that, The nickel plating treatment satisfies at least one of the following conditions: (1) The pH value of the nickel-plating solution during the nickel plating process is 3~6; (2) The temperature of the nickel melting solution during the nickel melting process is 60℃~80℃.

8. The method for gold plating of a glass substrate as described in any one of claims 1-5, characterized in that, The nickel plating solution satisfies at least one of the following conditions: (1) The nickel ion concentration in the nickel solution is 4 g / L to 6 g / L; (2) The mass concentration of phosphorus source contained in the nickel solution is 10 g / L to 40 g / L; (3) The nickel source contained in the nickel sulfate solution includes nickel sulfate; (4) The phosphorus source contained in the nickel solution includes sodium hypophosphite.

9. The method for gold plating of a glass substrate as described in any one of claims 1-5, characterized in that, The gold plating process satisfies at least one of the following conditions: (1) The pH value of the gold-plating solution during the gold plating process is 4~6; (2) The temperature of the gold-plating solution during the gold plating process is 70℃~90℃.

10. The method for gold plating of a glass substrate as described in any one of claims 1-5, characterized in that, The gold-containing solution satisfies at least one of the following conditions: (1) The concentration of gold ions in the gold-containing solution is 0.5 g / L to 1.5 g / L; (2) The gold-plating solution also contains citric acid, and the mass concentration of citric acid in the gold-plating solution is 5 g / L to 10 g / L; (3) The gold source contained in the gold solution includes potassium gold cyanide.

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