Method for improving adhesive force of filled hole of substrate

Abstract

The invention relates to the technical field of semiconductor packaging, in particular to a method for improving substrate hole filling adhesive force. The method for improving the substrate hole filling adhesive force comprises the following steps that titanium layer magnetron sputtering treatment and copper layer magnetron sputtering treatment are sequentially carried out on a substrate containing through holes, and a first substrate is obtained; and performing chemical copper plating treatment and electroplating treatment on the first substrate, and performing filling treatment on the through holes. The magnetron sputtering treatment comprises the steps of firstly depositing a titanium layer on the surface of the substrate and then depositing a copper layer, so that the adhesiveness of the copper layer is improved; and then chemical copper plating treatment is carried out, and the chemical copper plating treatment is that the substrate and the through holes are soaked in chemical copper plating liquid, so that metal deposition can be completely carried out on the through holes with a certain thickness, metal deposition can be carried out on the through holes in all directions, and the problems that metal is unevenly and incompletely filled in through hole channels are effectively solved. And then electroplating copper deposition treatment is carried out to ensure that the filling rate of the through hole is high, so that a product with excellent conductivity and high product yield is obtained.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor packaging technology, and in particular, relates to a method for improving the adhesion of substrate hole filling. Background Art

[0002] In the manufacturing process of semiconductors and packaging, the substrate hole filling process is often used; with the high performance demand of chips, higher requirements are also placed on advanced packaging technologies such as substrate through-holes (glass through-holes, silicon through-holes). There are two main problems with traditional silicon-based adapter board integration technology: 1) High cost. The silicon through-hole via (TSV) is made using a silicon etching process, and the silicon through-hole via still requires oxidation insulation layer, thin wafer holding and other technologies; 2) Poor electrical performance. Silicon material is a semiconductor material. When the transmission line transmits a signal, the signal has a strong electromagnetic coupling effect with the substrate material, and eddy currents are generated in the substrate, resulting in poor signal integrity (insertion loss, crosstalk, etc.). As a material that may replace silicon-based adapter boards, glass substrates require glass through-hole (substrate) technology.

[0003] After preparing the substrate glass through-hole, a hole filling plan needs to be implemented. The currently commonly used substrate hole filling process uses chemical copper deposition plus copper paste to plug the hole or chemical copper deposition plus electroplating copper deposition. The hole filling adhesion and conductivity are poor, and the thermal expansion coefficients of copper paste and glass are quite different, resulting in a high product defective rate.

[0004] Therefore, there is an urgent need to provide a method that can better improve the adhesion of substrate hole filling to achieve complete hole filling for different substrate materials. Summary of the invention

[0005] The purpose of the present application is to provide a method for improving the adhesion of substrate hole filling, aiming to solve the problems of poor adhesion and conductivity of substrate hole filling in the prior art.

[0006] In order to achieve the above application purpose, the technical solution adopted in this application is as follows:

[0007] In a first aspect, the present application provides a method for improving the adhesion of a substrate hole filling, comprising the following steps:

[0008] The substrate having the through hole is subjected to magnetron sputtering treatment of the titanium layer and magnetron sputtering treatment of the copper layer in sequence to obtain a first substrate;

[0009] The first substrate is subjected to chemical copper plating and electroplating, and the through holes are filled.

[0010] In some embodiments, in the steps of sequentially subjecting a substrate containing through holes to magnetron sputtering treatment of a titanium layer and a copper layer, the vacuum degree is adjusted to 0.3-0.5 Pa, the gas flow rate is 100-120 sccm, the power is 3-10 kW, and the substrate transfer speed is 0.2-1.0 m / min.

[0011] In some embodiments, during the magnetron sputtering process of the titanium layer, the coating time of the titanium layer is 10 to 200 seconds, and the thickness of the titanium layer is 15 to 500 nm.

[0012] In some embodiments, during the magnetron sputtering process of the copper layer, the coating time of the copper layer is 20 to 700 seconds, and the thickness of the copper layer is 50 to 2000 nm.

[0013] In some embodiments, the step of chemical copper plating includes:

[0014] Performing a de-impurity treatment on the first substrate to obtain a pre-treated first substrate;

[0015] Providing a chemical copper plating mixed solution, immersing the pretreated first substrate in the chemical copper plating mixed solution for pre-immersion treatment, and inducing a chemical copper deposition autocatalytic reaction through the activation of palladium nuclei;

[0016] A copper deposition reaction is performed on the surface of the first substrate and the through hole, and then a washing process is performed.

[0017] In some embodiments, the step of subjecting the first substrate to a de-impurity treatment to obtain a pre-treated first substrate includes: subjecting the first substrate to a de-oiling treatment, a hot water cleaning treatment, and a normal temperature water cleaning treatment in sequence; wherein the de-oiling treatment is performed at a temperature of 30 to 50°C for 3 to 5 minutes; the hot water cleaning treatment is performed at a temperature of 40 to 50°C for 1 to 2 minutes; and the normal temperature water cleaning treatment is performed at a temperature of 22 to 28°C for 1 to 2 minutes.

[0018] In some embodiments, the electroless copper plating mixture includes components in the following concentrations:

[0019] Copper salt 0.02-10g / L;

[0020] Complexing agent 5-10g / L;

[0021] Reducing agent 0.3-30g / L;

[0022] pH adjuster 0.1-0.5g / L.

[0023] In some embodiments, the copper salt includes any one of copper sulfate, copper chloride, copper nitrate, and copper hydroxide.

[0024] In some embodiments, the complexing agent includes any one of disodium edetate, sodium citrate, potassium sodium tartrate, and nitrilotriacetic acid.

[0025] In some embodiments, the reducing agent includes any one of formaldehyde, sodium hypophosphite, dimethylamine borane, and sodium borohydride.

[0026] In some embodiments, the pH adjuster includes any one of sodium citrate, sodium hydroxide, and sodium carbonate.

[0027] In some embodiments, the temperature of the electroplating process is 20-26° C., including any one of the following two electroplating schemes:

[0028] a. In the first stage, direct current is used for treatment, and the current density is 1 to 3ASD; in the second stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2);

[0029] b. In the first stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); in the second stage, direct current is used for treatment, and the current density is 1 to 10ASD.

[0030] In some embodiments, the substrate includes any one of a glass substrate, a silicon substrate, and a PCB board.

[0031] In some embodiments, the through-hole is a vertical hole or an X-shaped hole.

[0032] In some embodiments, the thickness of the substrate is 0.2 to 2 mm.

[0033] In some embodiments, the through hole has a diameter of 20-200 μm.

[0034] The first aspect of the present application provides a method for improving the adhesion of substrate hole filling, in which a substrate containing through holes is subjected to titanium layer magnetron sputtering treatment and copper layer magnetron sputtering treatment in sequence to obtain a first substrate; then the first substrate is subjected to chemical copper plating treatment and electroplating treatment to fill the through holes; the magnetron sputtering treatment first deposits a titanium layer on the surface of the substrate and then deposits a copper layer, thereby improving the adhesion of the copper layer; then a chemical copper plating treatment is performed, wherein the chemical copper plating treatment is to immerse both the substrate and the through hole in a chemical copper plating solution, which is conducive to complete metal deposition on the through hole with a certain thickness, so as to achieve all-round metal deposition on the through hole, and effectively improve the problem of uneven and incomplete metal filling in the through hole channel; then an electroplating copper deposition treatment is performed to ensure a high through hole filling rate, so as to obtain a product with excellent conductivity and high product yield; the method is conducive to improving the adhesion of the substrate hole filling, and can be applied to hole filling of various apertures, has a simple process, high efficiency, does not require the use of large-scale instruments and equipment, and is conducive to wide application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 This is the method for improving the adhesion of substrate hole filling provided in Example 1 of the present application. DETAILED DESCRIPTION

[0037] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0038] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0039] In this application, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0040] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0041] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "an" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0042] The weight of the relevant components mentioned in the embodiment description of the present application can not only refer to the specific content of each component, but also represent the proportional relationship between the weights of the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the embodiment description of the present application, it is within the scope disclosed in the embodiment description of the present application. Specifically, the mass in the embodiment description of the present application can be μg, mg, g, kg and other mass units known in the chemical industry.

[0043] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0044] The first aspect of the present application provides a method for improving the adhesion of substrate hole filling, such as Figure 1 As shown, the following steps are included:

[0045] S01. The substrate containing the through hole is sequentially subjected to magnetron sputtering treatment of the titanium layer and the copper layer to obtain a first substrate;

[0046] S02. Perform chemical copper plating and electroplating on the first substrate, and fill the through holes.

[0047] The first aspect of the embodiment of the present application provides a method for improving the adhesion of substrate hole filling, in which a substrate containing through holes is subjected to titanium layer magnetron sputtering treatment and copper layer magnetron sputtering treatment in sequence to obtain a first substrate; then the first substrate is subjected to chemical copper plating treatment and electroplating treatment to fill the through holes; the magnetron sputtering treatment first deposits a titanium layer on the surface of the substrate and then deposits a copper layer, thereby improving the adhesion of the copper layer; then a chemical copper plating treatment is performed, wherein the chemical copper plating treatment is to immerse both the substrate and the through hole in a chemical copper plating solution, which is conducive to complete metal deposition on the through hole with a certain thickness, so as to achieve all-round metal deposition on the through hole, and effectively improve the problem of uneven and incomplete metal filling in the through hole channel; then an electroplating copper deposition treatment is performed to ensure a high through hole filling rate, so as to obtain a product with excellent conductivity and high product yield; the method is conducive to improving the adhesion of the substrate hole filling, and can be applied to hole filling of various apertures, has a simple process, high efficiency, does not require the use of large-scale instruments and equipment, and is conducive to wide application.

[0048] In step S01, a titanium layer and a copper layer of a substrate having a through hole are sequentially subjected to magnetron sputtering treatment to obtain a first substrate.

[0049] In some embodiments, the substrate includes any one of a glass substrate, a silicon substrate, and a PCB board.

[0050] In some embodiments, the through-hole is a vertical hole or an X-shaped hole.

[0051] In some embodiments, the thickness of the substrate is 0.2-2 mm. In some specific embodiments, the thickness of the substrate includes but is not limited to 0.2 mm, 0.4 mm, 0.5 mm, 0.7 mm, 1.0 mm, 1.2 mm, 1.5 mm, 1.7 mm, and 2 mm.

[0052] In some embodiments, the pore size of the through hole is 20-200 μm. In some specific embodiments, the pore size of the through hole includes but is not limited to 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm.

[0053] The principle of magnetron sputtering is to fill Ar gas in a vacuum environment, and then apply an electromagnetic field between the metal target and the substrate to ionize it to produce glow discharge. The Ar gas is accelerated to move toward the target and bombard the target. Finally, the target particles escaping from the target surface are deposited on the substrate and grow into a thin film. The thickness of the copper layer deposited by magnetron sputtering is uniform and easy to control, and the preparation method is simple.

[0054] In some embodiments, in the steps of sequentially performing magnetron sputtering treatments on the titanium layer and the copper layer on the substrate having the through hole, the vacuum degree is adjusted to 0.3-0.5 Pa, the gas flow rate is 100-120 sccm, the power is 3-10 kW, and the substrate transmission speed is 0.2-1.0 m / min. By controlling the conditions of the magnetron sputtering treatment, the performance of the coating obtained by the magnetron sputtering treatment can be guaranteed.

[0055] In some embodiments, during the magnetron sputtering process of the titanium layer, the coating time of the titanium layer is 10 to 200 seconds, and the thickness of the titanium layer is 5 to 500 nm. The coating time of the titanium layer is controlled to be 10 to 200 seconds to ensure that the thickness of the titanium layer is moderate, and the titanium layer is deposited first to improve the adhesion of the copper layer and ensure that the copper layer is not easy to fall off.

[0056] In some specific embodiments, in the magnetron sputtering process of the titanium layer, the coating time of the titanium layer includes but is not limited to 10 seconds, 30 seconds, 50 seconds, 70 seconds, 90 seconds, 110 seconds, 130 seconds, 150 seconds, 170 seconds, and 200 seconds. The thickness of the titanium layer includes but is not limited to 5nm, 10nm, 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 200nm, 300nm, 400nm, and 500nm.

[0057] In some embodiments, in the copper layer magnetron sputtering treatment, the copper layer is plated for 20 to 700 seconds, and the thickness of the copper layer is 50 to 2000 nm. In the process of copper layer magnetron sputtering treatment, a titanium layer is first deposited on the surface of the substrate, and then a copper layer is deposited on the surface of the titanium layer. The obtained copper layer has high adhesion and is not easy to fall off. In some specific embodiments, the copper layer plating time includes but is not limited to 20 seconds, 50 seconds, 100 seconds, 150 seconds, 200 seconds, 250 seconds, 300 seconds, 350 seconds, 400 seconds, 450 seconds, 500 seconds, 550 seconds, 600 seconds, 650 seconds, 700 seconds, 750 seconds, 800 seconds, 850 seconds, 900 seconds, 950 seconds, 1000 seconds, 1500 seconds, 2000 seconds. The thickness of the copper layer includes but is not limited to 50nm, 100nm, 120nm, 150nm, 170nm, 200nm, 220nm, 250nm, 270nm, 300nm, 320nm, 350nm, 370nm, 400nm, 420nm, 450nm, 470nm, 500nm, 700nm, 1000nm, 1500nm, and 2000nm.

[0058] However, in the method of magnetron sputtering copper plating, only the substrate surface and the position of the through-hole wall close to the substrate surface can be effectively covered with magnetron sputtering copper plating. For glass through-holes with rough hole walls and complex morphology, magnetron sputtering cannot effectively copper-plate the entire internal channel of the through-hole. In order to solve the problem of metal plating treatment of through-holes with rough hole walls, complex hole shapes and ultra-high aspect ratio, a method of chemical copper plating is further provided for further treatment. Chemical copper plating is a metal deposition process in which copper ions are reduced under the autocatalytic action of the metal surface by a reducing agent in the solution; the copper plating method can achieve copper plating treatment at various positions in the through-hole, which is conducive to complete metal deposition of through-holes with a certain thickness, so as to achieve metal deposition in all directions of the through-hole, and effectively improve the problem of uneven and incomplete metal filling in the through-hole channel.

[0059] Step S02: Perform chemical copper plating and electroplating on the first substrate, and fill the through holes.

[0060] In some embodiments, the chemical copper plating process uses sodium hypophosphite as a reducing agent to reduce copper ions to metallic copper under appropriate conditions, thereby forming a uniform and dense copper plating layer on the surface of the deposited material. Specifically, the mechanism of sodium hypophosphite reducing copper is: copper ions are reduced to metallic copper, and hypophosphite ions are oxidized to phosphite ions. The reaction equation is as follows:

[0061] 2H2PO 2- +Cu 2+ +2OH - ——Cu+2H2PO3 - +H2.

[0062] In some embodiments, the step of chemical copper plating includes:

[0063] S021. performing a de-doping treatment on the first substrate to obtain a pre-treated first substrate;

[0064] S022 provides a chemical copper plating mixture, the pre-treated first substrate is immersed in the chemical copper plating mixture for pre-immersion treatment, the activation of the palladium core induces an electroless copper deposition autocatalytic reaction;

[0065] S023. Perform copper deposition reaction on the surface of the first substrate and the through-hole, and then perform a washing process.

[0066] In step S021, the first substrate is subjected to a de-impurity treatment to obtain a pre-treated first substrate.

[0067] In some embodiments, the step of subjecting the first substrate to a de-impurity treatment to obtain a pre-treated first substrate includes: subjecting the first substrate to a de-oiling treatment, a hot water cleaning treatment, and a normal temperature water cleaning treatment in sequence; wherein the de-oiling treatment is performed at a temperature of 30 to 50°C for 3 to 5 minutes; the hot water cleaning treatment is performed at a temperature of 40 to 50°C for 1 to 2 minutes; and the normal temperature water cleaning treatment is performed at a temperature of 22 to 28°C for 1 to 2 minutes.

[0068] In step S022, a chemical copper plating mixed solution is provided, and the pre-treated first substrate is immersed in the chemical copper plating mixed solution for pre-immersion treatment, so as to induce a chemical copper deposition autocatalytic reaction through the activation of the palladium core.

[0069] In some embodiments, the electroless copper plating mixture includes components in the following concentrations:

[0070] Copper salt 0.02-10g / L;

[0071] Complexing agent 5-10g / L;

[0072] Reducing agent 0.3-30g / L;

[0073] pH adjuster 0.1-0.5g / L.

[0074] In some embodiments, the copper salt includes any one of copper sulfate, copper chloride, copper nitrate, and copper hydroxide. Increasing the concentration of the copper salt can increase the copper deposition rate, but will reduce the stability of the plating solution.

[0075] In some embodiments, the complexing agent includes any one of disodium ethylenediaminetetraacetic acid, sodium citrate, potassium sodium tartrate, and nitrilotriacetic acid. To avoid the precipitation of copper hydroxide in the alkaline plating solution. The complexing agent and the copper salt form a complex through coordination effect. The complexed copper ions can provide free copper ions for the chemical plating reaction, and can effectively prevent the hydrolysis of divalent copper ions, improve the stability of the plating solution, and improve the performance of the chemical copper plating layer.

[0076] In some embodiments, the reducing agent includes any one of formaldehyde, sodium hypophosphite, dimethylamine borane, and sodium borohydride.

[0077] In some embodiments, the pH regulator includes any one of sodium citrate, sodium hydroxide, and sodium carbonate. In chemical copper plating, formaldehyde needs to be in a strongly alkaline environment to provide electrons as a reducing agent. In addition, hydrogen is generated during the chemical copper plating process, which changes the pH of the plating solution. Therefore, a regulator such as sodium hydroxide needs to be used regularly to control the pH to maintain it within the required range.

[0078] Furthermore, the pretreated first substrate is immersed in a chemical copper plating mixed solution for pre-dipping treatment, and the chemical copper deposition autocatalytic reaction is induced by the activation of the palladium core.

[0079] In some embodiments, the pre-preg treatment is performed at a temperature of 22 to 28° C. and for a time of 1 to 3 minutes.

[0080] In some embodiments, the activation temperature of the palladium core is 25-35° C., and the activation time is 5 to 20 minutes.

[0081] In step S023, copper deposition is performed on the first substrate and the through-hole surface, and then a washing process is performed. In some embodiments, copper deposition is performed on the first substrate and the through-hole surface at a temperature of 25 to 50° C. and for 10 to 60 minutes.

[0082] In some embodiments, washing treatment is required after the copper plating reaction is completed, and water washing treatment is adopted, wherein the water washing treatment time is 22-28° C. and the time is 1-3 minutes to remove impurities on the surface of the chemically plated copper.

[0083] Furthermore, electroplating is performed to achieve complete filling of the through hole.

[0084] In some embodiments, the temperature of the electroplating process is 20-26°C.

[0085] In some embodiments, the electroplating process includes any one of the following two electroplating schemes:

[0086] a. In the first stage, direct current is used for treatment, and the current density is 1 to 3ASD; in the second stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2);

[0087] b. In the first stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); in the second stage, direct current is used for treatment, and the current density is 1 to 10ASD.

[0088] The following describes the invention in conjunction with specific embodiments.

[0089] Example 1

[0090] A method for improving substrate hole filling adhesion

[0091] The specific method includes the following steps:

[0092] A substrate with a through hole is provided, wherein the substrate is a glass substrate with a thickness of 0.5 mm; the through hole is an X-shaped hole with a hole diameter of 50 μm;

[0093] A titanium target material and a copper target material are sequentially provided for magnetron sputtering treatment, and the conditions of the magnetron sputtering treatment are as follows: a vacuum degree of 0.4 Pa, a gas flow rate of 100 sccm, a power of 4 kW, a coating time of the titanium layer of 60 seconds, and a thickness of the titanium layer of 30 nm; a coating time of the copper layer of 100 seconds, and a thickness of the copper layer of 500 nm, to obtain a first substrate;

[0094] The first substrate is treated with sodium hypophosphite chemical copper plating; specifically comprising the following steps: the first substrate is subjected to degreasing treatment, hot water cleaning treatment and room temperature water cleaning treatment in sequence; wherein the temperature of the degreasing treatment is 30°C and the time is 5 minutes; the temperature of the hot water cleaning treatment is 40°C and the time is 1 minute; the temperature of the room temperature water cleaning treatment is 22°C and the time is 1 minute; then the pre-treated first substrate is immersed in a chemical copper plating mixed solution for 22°C pre-immersion treatment for 2 minutes, and activated by palladium nucleus at 25°C for 10 minutes to induce chemical copper deposition autocatalytic reaction; copper deposition reaction is carried out on the surface of the first substrate and the through hole, and the temperature of the copper deposition reaction is 25°C and the time is 20 minutes; and then washing treatment is carried out;

[0095] Then, electroplating treatment is carried out at a temperature of 23°C. The following electroplating scheme is used for treatment: a direct current is used for treatment in the first stage, and a current density is 1 to 3ASD; a pulse current is used for treatment in the second stage, and a current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); and the through hole is completely filled.

[0096] Example 2

[0097] A method for improving substrate hole filling adhesion

[0098] The specific method includes the following steps:

[0099] A substrate with a through hole is provided, wherein the substrate is a silicon substrate with a thickness of 1 mm; the through hole is a vertical hole with a hole diameter of 70 μm;

[0100] A titanium target material and a copper target material are sequentially provided for magnetron sputtering treatment, and the conditions of the magnetron sputtering treatment are as follows: a vacuum degree of 0.45 Pa, a gas flow rate of 110 sccm, a power of 6 kW, a titanium layer coating time of 60 seconds, and a titanium layer thickness of 50 nm; a copper layer coating time of 150 seconds, and a copper layer thickness of 700 nm, to obtain a first substrate;

[0101] The first substrate is treated with sodium hypophosphite chemical copper plating; specifically comprising the following steps: the first substrate is subjected to degreasing treatment, hot water cleaning treatment and room temperature water cleaning treatment in sequence; wherein the temperature of the degreasing treatment is 40°C and the time is 3 minutes; the temperature of the hot water cleaning treatment is 45°C and the time is 2 minutes; the temperature of the room temperature water cleaning treatment is 23°C and the time is 2 minutes; then the pre-treated first substrate is immersed in a chemical copper plating mixed solution for 23°C pre-immersion treatment for 2 minutes, and activated by palladium nuclei at 30°C for 10 minutes to induce chemical copper deposition autocatalytic reaction; copper deposition reaction is carried out on the surface of the first substrate and the through hole, and the temperature of the copper deposition reaction is 25°C and the time is 30 minutes; and then washing treatment is carried out;

[0102] Then, electroplating treatment is carried out at a temperature of 23°C. The following electroplating scheme is used for treatment: a direct current is used for treatment in the first stage, and a current density is 1 to 3ASD; a pulse current is used for treatment in the second stage, and a current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); and the through hole is completely filled.

[0103] Example 3

[0104] A method for improving substrate hole filling adhesion

[0105] The specific method includes the following steps:

[0106] A substrate with a through hole is provided, wherein the substrate is a PCB substrate with a thickness of 1.5 mm; the through hole is a vertical hole with a hole diameter of 200 μm;

[0107] A titanium target material and a copper target material are sequentially provided for magnetron sputtering treatment, and the conditions of the magnetron sputtering treatment are as follows: a vacuum degree of 0.5 Pa, a gas flow rate of 120 sccm, a power of 8 kW, a coating time of 60 seconds for the titanium layer, and a thickness of 70 nm for the titanium layer; a coating time of 300 seconds for the copper layer, and a thickness of 1000 nm for the copper layer, to obtain a first substrate;

[0108] The first substrate is treated with sodium hypophosphite chemical copper plating; specifically comprising the following steps: the first substrate is subjected to degreasing treatment, hot water cleaning treatment and room temperature water cleaning treatment in sequence; wherein the temperature of the degreasing treatment is 50°C and the time is 10 minutes; the temperature of the hot water cleaning treatment is 45°C and the time is 2 minutes; the temperature of the room temperature water cleaning treatment is 25°C and the time is 2 minutes; then the pretreated first substrate is immersed in a chemical copper plating mixed solution for 28°C pre-immersion treatment for 3 minutes, and activated by palladium nucleus at 30°C for 12 minutes to induce chemical copper deposition autocatalytic reaction; copper deposition reaction is carried out on the surface of the first substrate and the through hole, and the temperature of the copper deposition reaction is 50°C and the time is 60 minutes; and then washing treatment is carried out;

[0109] Then electroplating treatment is carried out at a temperature of 23°C. The following electroplating scheme is used for treatment: in the first stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); in the second stage, direct current is used for treatment, and the current density is 1 to 10ASD.

[0110] Comparative Example 1

[0111] A method for improving substrate hole filling adhesion

[0112] The specific method includes the following steps:

[0113] A substrate with a through hole is provided, wherein the substrate is a glass substrate with a thickness of 0.5 mm; the through hole is an X-shaped hole with a hole diameter of 50 μm;

[0114] Titanium target and copper target are provided in turn for magnetron sputtering treatment. The conditions of the magnetron sputtering treatment are as follows: vacuum degree of 0.5 Pa, gas flow rate of 120 sccm, power of 8 kW, coating time of titanium layer of 60 seconds, thickness of titanium layer of 30 nm, coating time of copper layer of 100 seconds, thickness of copper layer of 500 nm.

[0115] Then electroplating is carried out at a temperature of 23°C, and the following electroplating scheme is used. In the first stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); in the second stage, direct current is used for treatment, and the current density is 1 to 10ASD, so as to achieve complete filling of the through hole.

[0116] Comparative Example 2

[0117] A method for improving substrate hole filling adhesion

[0118] The specific method includes the following steps:

[0119] A substrate with a through hole is provided, wherein the substrate is a glass substrate with a thickness of 0.5 mm; the through hole is a vertical hole with a diameter of 150 μm;

[0120] The first substrate is treated with sodium hypophosphite chemical copper plating; specifically comprising the following steps: the first substrate is subjected to degreasing treatment, hot water cleaning treatment and room temperature water cleaning treatment in sequence; wherein the temperature of the degreasing treatment is 45°C and the time is 5 minutes; the temperature of the hot water cleaning treatment is 45°C and the time is 1 minute; the temperature of the room temperature water cleaning treatment is 25°C and the time is 2 minutes; then the pretreated first substrate is immersed in a chemical copper plating mixed solution for 28°C pre-immersion treatment for 3 minutes, and activated by palladium core at 30°C for 10 minutes to induce chemical copper deposition autocatalytic reaction; copper deposition reaction is carried out on the surface of the first substrate and the through hole, and the temperature of the copper deposition reaction is 50°C and the time is 60 minutes; and then washing treatment is carried out;

[0121] Then, electroplating treatment is carried out at a temperature of 23°C, and the following electroplating scheme is used for treatment. In the first stage, direct current is used for treatment, and the current density is 1 to 3ASD; in the second stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2), so as to achieve complete filling of the through hole.

[0122] Performance testing and result analysis

[0123] Further, the products obtained by processing Examples 1 to 3 and Comparative Examples 1 to 2 were tested and analyzed for adhesion, hole filling, hole filling depression and yield. The results are shown in Table 1. It can be seen that the adhesion of the products obtained in Examples 1 to 3 is 5B, the adhesion of the product obtained in Comparative Example 1 is 4B, and the adhesion of the product obtained in Comparative Example 2 is poor; for the position of the hole filling, no hole filling voids were found in Examples 1 to 3, the product of Comparative Example 1 had hole filling voids, and Comparative Example 2 had no hole filling voids; the formed hole filling voids were further analyzed to analyze whether there were depressions in the hole filling, and there were no hole filling voids in Example 1, so there were no hole filling depressions; the hole filling depression of Example 2 was less than 5μm, the hole filling depression of Example 3 was less than 3μm, the hole filling depression of Comparative Example 1 was less than 5μm, and the hole filling depression of Comparative Example 2 was greater than 10μm. The yield was further determined. The yield of Example 1 was 100%, the yield of Example 2 was >98%, the yield of Example 3 was >98%, the yield of Comparative Example 1 was <65%, and the yield of Comparative Example 2 was <70%.

[0124] It can be seen that the product obtained by the method provided in Example 1 has strong adhesion, no filling voids, no filling depressions, and the yield rate reaches 100%.

[0125] Table 1

[0126] Adhesion Filling holes Filling Hole Depression Yield Example 1 5B none none 100％ Example 2 5B none <5μm ＞98％ Example 3 5B none <3μm ＞98％ Comparative Example 1 4B have <5μm ＜65％ Comparative Example 2 bad none >10μm ＜70％

[0127] In summary, the embodiment of the present application provides a method for improving the adhesion of substrate hole filling, in which a substrate containing a through hole is sequentially subjected to titanium layer magnetron sputtering treatment and copper layer magnetron sputtering treatment to obtain a first substrate; then the first substrate is subjected to chemical copper plating treatment and electroplating treatment to fill the through hole; the magnetron sputtering treatment first deposits a titanium layer on the surface of the substrate and then deposits a copper layer, thereby improving the adhesion of the copper layer; then a chemical copper plating treatment is performed, and the chemical copper plating treatment is to immerse the substrate and the through hole in a chemical copper plating solution, which is beneficial to completely depositing metal on the through hole with a certain thickness, so as to achieve all-round metal deposition on the through hole, and effectively improve the problem of uneven and incomplete filling of the metal in the through hole channel; then an electroplating copper deposition treatment is performed to ensure a high through hole filling rate, so as to obtain a product with excellent conductivity and high product yield; the method is beneficial to improving the adhesion of the substrate hole filling, and can be applied to hole filling of various apertures, has a simple process, high efficiency, does not require the use of large-scale instruments and equipment, and is conducive to wide application.

[0128] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for improving the adhesion of substrate hole filling, characterized in that: The steps include: The substrate having the through hole is subjected to magnetron sputtering treatment of the titanium layer and magnetron sputtering treatment of the copper layer in sequence to obtain a first substrate; The first substrate is subjected to chemical copper plating and electroplating, and the through holes are filled.

2. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: In the steps of sequentially subjecting the substrate containing the through holes to magnetron sputtering treatment of the titanium layer and the copper layer, the vacuum degree is adjusted to 0.3-0.5 Pa, the gas flow rate is 100-120 sccm, the power is 3-10 kW, and the substrate transmission speed is 0.2-1.0 m / min.

3. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: In the magnetron sputtering treatment of the titanium layer, the coating time of the titanium layer is 10 to 200 seconds, and the thickness of the titanium layer is 5 to 500 nm.

4. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: In the copper layer magnetron sputtering treatment, the copper layer is plated for 20 to 700 seconds and has a thickness of 50 to 2000 nm.

5. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: The steps of chemical copper plating include: Performing a de-impurity treatment on the first substrate to obtain a pre-treated first substrate; Providing a chemical copper plating mixed solution, immersing the pretreated first substrate in the chemical copper plating mixed solution for pre-immersion treatment, and inducing a chemical copper deposition autocatalytic reaction through the activation of palladium cores; A copper deposition reaction is performed on the first substrate and the surface of the through hole, and then a washing treatment is performed.

6. The method for improving the adhesion of substrate hole filling according to claim 5, characterized in that: The step of subjecting the first substrate to a de-impurity treatment to obtain a pre-treated first substrate includes: subjecting the first substrate to a de-oiling treatment, a hot water cleaning treatment and a normal temperature water cleaning treatment in sequence; wherein the temperature of the de-oiling treatment is 30 to 50° C. and the time is 3 to 5 minutes; the temperature of the hot water cleaning treatment is 40 to 50° C. and the time is 1 to 2 minutes; the temperature of the normal temperature water cleaning treatment is 22 to 28° C. and the time is 1 to 2 minutes.

7. The method for improving the adhesion of substrate hole filling according to claim 5, characterized in that: The chemical copper plating mixed solution includes components with the following concentrations:

8. The method for improving the adhesion of substrate hole filling according to claim 7, characterized in that: The copper salt includes any one of copper sulfate, copper chloride, copper nitrate and copper hydroxide; and / or, The complexing agent includes any one of disodium ethylenediaminetetraacetate, sodium citrate, potassium sodium tartrate, and nitrilotriacetic acid; and / or, The reducing agent includes any one of formaldehyde, sodium hypophosphite, dimethylamine borane and sodium borohydride; and / or, The pH adjuster includes any one of sodium citrate, sodium hydroxide and sodium carbonate.

9. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: The electroplating treatment temperature is 20-26°C, including any one of the following two electroplating schemes: a. In the first stage, direct current is used for treatment, and the current density is 1 to 3ASD; in the second stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); b. In the first stage, pulse current is used for treatment, and the current density is 2 to 5ASD, wherein the density ratio of the forward current to the reverse current is 1:(-3 to -2); in the second stage, direct current is used for treatment, and the current density is 1 to 10ASD.

10. The method for improving the adhesion of substrate hole filling according to claim 1, characterized in that: The substrate includes any one of a glass substrate, a silicon substrate, and a PCB board; and / or, The through hole is a vertical hole or an X-shaped hole; and / or, The thickness of the substrate is 0.2 to 2 mm; and / or, The through hole has a diameter of 20 to 200 μm.

Images