Surface grafting modified substrate and preparation method thereof

Abstract

The invention relates to a surface grafting modified substrate and a preparation method thereof. According to the preparation method, thiosulfate is adopted as an inorganic modifier, and the thiosulfate and epoxy groups on the surface of an epoxy resin substrate are subjected to chemical reaction, so that the surface of the substrate is grafted and modified. After modification, new hydroxyl groups can be generated on the surface of the substrate, the chemical bonding effect of the substrate and copper is improved, and the interface bonding force is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of chip packaging, and in particular to a surface grafted modified substrate and a preparation method thereof. Background Art

[0002] Epoxy-phenol resin-based substrates are widely used in the manufacture of FCBGA (Flip Chip Ball Grid Array) substrates. However, due to the high surface roughness of these substrates, copper plating increases the risk of permeation during surface plating, increasing signal transmission loss, restricting the manufacture of fine circuits on the substrates and thus limiting the application and development of large-scale substrates. Epoxy-phenolic resin-based and epoxy-cyanate resin-based substrates do not suffer from the high surface roughness defect and are suitable for large-scale substrate manufacturing. However, due to their extremely high filler loading and smaller filler size, the chemical bonding and mechanical interlocking effect of the substrate surface are greatly weakened, significantly restricting the level of heterogeneous interface bonding strength on the substrates and hindering the manufacture and application of large-scale substrates.

[0003] Therefore, it is necessary to improve the substrate surface to enhance the bonding strength of the substrate heterogeneous interface. Summary of the Invention

[0004] In order to solve the problems existing in the background technology, the present invention provides a method for preparing a surface grafted modified substrate, which realizes the grafting modification of the substrate surface and improves the bonding strength level of the heterogeneous interface of the substrate.

[0005] Specifically, the first aspect of the present invention provides a method for preparing a surface grafted modified substrate, comprising the following steps:

[0006] The epoxy resin substrate is placed in a thiosulfate solution, and the epoxy groups on the surface of the epoxy resin substrate react with the thiosulfate to obtain the surface grafted modified substrate.

[0007] This invention uses thiosulfate as an inorganic modifier. By chemically reacting the thiosulfate with epoxy groups on the surface of an epoxy resin substrate, the substrate surface is grafted onto the modified surface. After the modification, new hydroxyl groups are generated on the substrate surface, increasing the chemical bonding between the substrate and copper and improving interfacial bonding strength.

[0008] Compared with other organic modifiers, thiosulfate has the characteristics of high thermal stability, good water solubility, mild chemical modification conditions (normal pressure, below 60°C), non-volatility, non-corrosiveness, no special odor, and non-toxicity, making it extremely suitable for substrate wet processing.

[0009] In some embodiments, the reaction temperature may be 40-60° C., for example, 40° C., 45° C., 50° C., 55° C., or 60° C. The reaction time may be 5-15 min, for example, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min, or 15 min.

[0010] In some embodiments, the thiosulfate comprises one or more of sodium thiosulfate, potassium thiosulfate, or ammonium thiosulfate. Preferably, the thiosulfate is sodium thiosulfate. Sodium thiosulfate has the characteristics of high thermal stability, good water solubility, mild chemical modification conditions, non-volatility, non-corrosiveness, no special odor, and non-toxicity.

[0011] In some embodiments, before placing the epoxy resin substrate in the thiosulfate solution, the preparation method further includes placing the epoxy resin substrate in an oxidant solution for oxidation. The oxidation treatment can destroy the resin macromolecular chains on the surface of the epoxy resin substrate, roughening the surface of the resin substrate, thereby facilitating sufficient contact and reaction between the thiosulfate and free epoxy groups.

[0012] Preferably, the oxidant is one or more of potassium permanganate, hydrogen peroxide, peracetic acid, sodium dichromate, chromic acid, nitric acid, ammonium persulfate, sodium hypochlorite, sodium percarbonate, sodium perborate, and potassium perborate. The oxidation temperature is 70-90°C, for example, 70°C, 75°C, 80°C, 85°C or 90°C. If the oxidation temperature is too high, the surface roughening will accelerate, while if the oxidation temperature is too low, the surface roughening rate will be too slow and the surface roughening degree will be low. The oxidation time can be 5-15min, for example, 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min or 15min. If the oxidation time is too long, the surface resin will be excessively removed, which will not only reduce the roughness but also significantly reduce the thickness of the deposited film; if the oxidation time is too short, the surface roughening degree will be insufficient, the density of free epoxy groups will be insufficient, and the surface chemical grafting rate will be restricted.

[0013] In some embodiments, the epoxy resin substrate includes a core plate and epoxy resin deposited films disposed on the upper and lower surfaces of the core plate. The epoxy resin deposited films are made of a mixture of high-molecular-weight epoxy resin and silica filler. The core plate can be a silicon substrate, a ceramic substrate, a glass substrate, or an epoxy resin composite material composed of epoxy resin and glass fiber.

[0014] According to the filling amount of silicon oxide filler, the epoxy resin stacking film can be divided into low-filling resin stacking film, high-filling resin stacking film and ultra-high-filling resin stacking film. Filling fillers will weaken the chemical bonding and mechanical interlocking effect of the substrate surface, thereby restricting the level of substrate heterogeneous interface bonding, and as the filling amount increases, the weakening effect increases. Using the method of the present invention, by reacting thiosulfate with the epoxy groups on the film surface to generate new hydroxyl groups, the surface polar group density and quantity and adhesion of the substrate of the high-filling and ultra-high-filling system can be significantly improved, and the chemical bonding between the substrate and the metallic copper can be improved, thereby solving the problem of reduced substrate heterogeneous interface bonding due to high filler filling amount.

[0015] In some embodiments, the high molecular weight epoxy resin is an epoxy-phenolic resin or an epoxy-cyanate resin. Epoxy-phenolic resin and epoxy-cyanate resin substrates have a low degree of surface roughness and a low risk of copper plating during surface copper plating, making them suitable for large-scale substrate manufacturing.

[0016] In some embodiments, the method for preparing the epoxy resin substrate includes:

[0017] Fixing the two epoxy resin deposition films on the upper and lower surfaces of the core plate respectively, and then performing a heat pressing process at a temperature of 110-130° C. and a vacuum state of 0.5-0.7 MPa;

[0018] After hot pressing, the obtained samples were pre-cured at 100-120°C for 20-40 min and 180-200°C for 10-40 min.

[0019] After pre-curing, the sample surface is cleaned and then fluffed in a fluffing agent at 50-70°C for 5-20 minutes.

[0020] In some specific embodiments, the thermal compression temperature may be 110° C., 115° C., 120° C., 125° C., or 130° C. The thermal compression pressure may be 0.5 MPa, 0.55 MPa, 0.6 MPa, 0.65 MPa, or 0.7 MPa.

[0021] In some specific embodiments, a first pre-curing treatment may be performed at 100-120° C. for 20-40 minutes, and then a second pre-curing treatment may be performed at 180-200° C. for 20-40 minutes. The purpose of the pre-curing is to further cross-link and cure the resin deposition film.

[0022] In some specific embodiments, the temperature of the first pre-curing treatment may be 100° C., 105° C., 110° C., 115° C., or 120° C., and the time may be 20 min, 25 min, 30 min, 35 min, or 40 min.

[0023] In some specific embodiments, the temperature of the second pre-curing treatment may be 180° C., 185° C., 190° C., 195° C., or 200° C., and the time may be 20 min, 25 min, 30 min, 35 min, or 40 min.

[0024] In some specific embodiments, the temperature of the fluffing agent can be 50°C, 55°C, 60°C, 65°C, or 70°C. The fluffing time can be 5 minutes, 10 minutes, 15 minutes, or 20 minutes. The purpose of fluffing the epoxy resin substrate is to expose the silicon oxide filler in the epoxy resin deposited film on the film surface. This can increase the mechanical anchoring force between the film and the copper, enhance interfacial adhesion, and improve the bonding strength of the copper circuit.

[0025] In some embodiments, the cleaning process includes placing the sample in an alkaline solution to remove oil contamination, then ultrasonically washing the sample and drying the sample. The alkaline solution may be a sodium carbonate solution. Ultrasonic washing can remove surface impurities.

[0026] In some embodiments, the bulking agent is one or more of 2-(2-butoxyethoxy)ethanol, dimethylformamide, dihydroxy diethyl butyl ether, and ethylene glycol.

[0027] In some embodiments, after the reaction is completed, the preparation method further comprises: performing chemical plating and electroplating on the surface grafted modified substrate; baking; and curing.

[0028] After the surface of the epoxy resin substrate is grafted and modified by a modifier, new hydroxyl groups will be generated, which will increase the chemical bonding between the substrate and the copper plating and improve the interface bonding strength.

[0029] The present invention is not particularly limited to chemical plating and electroplating, and any process that can plate metal on the surface of a resin substrate can be used in the present invention.

[0030] In some specific embodiments, the baking temperature may be 180-200° C., such as 180° C., 185° C., 190° C., 195° C., or 200° C. The baking time may be 30-90 min, such as 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, or 90 min.

[0031] In a second aspect, the present invention provides a surface grafted modified substrate obtained by the above preparation method. The substrate of the present invention has a high interface bonding strength and meets the manufacturing requirements of large-scale substrates.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] This invention provides a method for preparing a surface-grafted modified substrate. The method uses thiosulfate as an inorganic modifier. The surface of the epoxy resin substrate undergoes a chemical reaction between the thiosulfate and epoxy groups, achieving graft modification. After modification, new hydroxyl groups are generated on the substrate surface, increasing the chemical bonding between the substrate and copper and improving interfacial adhesion. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Graphs showing the interface bonding force between the modified substrates prepared in Examples 1-3 and Comparative Example 1 and copper. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific 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.

[0036] Unless otherwise defined, the technical terms used in the following examples have the same meanings as commonly understood by those skilled in the art to which this invention belongs. The experimental reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the raw materials, instruments, and equipment used in the following examples are all commercially available or can be obtained through existing methods; the amounts of the experimental reagents used, unless otherwise specified, are the amounts used in conventional experimental procedures; and the experimental methods, unless otherwise specified, are all conventional methods.

[0037] Example 1

[0038] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 120°C and 0.6 MPa in vacuum;

[0039] (2) After lamination, the samples were pre-cured at 100°C for 30 min and 180°C for 30 min.

[0040] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 60°C for 10 min.

[0041] (4) After fluffing, transfer to 80℃ potassium permanganate solution for oxidation treatment for 10 minutes;

[0042] (5) After oxidation, the substrate was placed in a 50°C sodium thiosulfate solution for chemical modification and grafting reaction for 8 min;

[0043] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0044] (7) After copper electroplating, the substrate was baked at 150°C for 60 min to remove moisture, and then cured at 190°C for 90 min to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0045] Interface bonding strength test between modified substrate and copper:

[0046] (1) Cut the substrate into 60×13 mm strips for testing.

[0047] (2) Evenly peel off the copper sheet on the surface of the long sample from the substrate surface with a length of 15 mm;

[0048] (3) Use the lower fixture of the universal testing machine to keep the sample in a horizontal state;

[0049] (4) Fold the uncovered copper sheet along the unpeeled copper sheet into a shape 90° to the horizontal sample, and then fix the starting end of the uncovered copper sheet with the upper fixture of the universal testing machine;

[0050] (5) After fixing the sample, pull the copper sheet vertically upward at a tensile speed of 50 mm / min until the test stops automatically, and the peeling test is completed. Figure 1 As shown in .

[0051] Example 2

[0052] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 120°C and 0.6 MPa in vacuum;

[0053] (2) After lamination, the samples were pre-cured at 100°C for 30 min and 180°C for 20 min.

[0054] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 60°C for 10 min.

[0055] (4) After fluffing, transfer to 80℃ potassium permanganate solution for oxidation treatment for 10 minutes;

[0056] (5) After oxidation, the substrate was placed in a 50°C sodium thiosulfate solution for chemical modification and grafting reaction for 8 min;

[0057] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0058] (7) After copper electroplating, the substrate was baked at 150°C for 60 minutes to remove moisture, and then cured at 190°C for 90 minutes to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0059] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1. The results are as follows: Figure 1 shown.

[0060] Example 3

[0061] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 120°C and 0.6 MPa in vacuum;

[0062] (2) After lamination, the samples were pre-cured at 100°C for 30 min and 180°C for 10 min.

[0063] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 60°C for 10 min.

[0064] (4) After fluffing, transfer to 80℃ potassium permanganate solution for oxidation treatment for 10 minutes;

[0065] (5) After oxidation, the substrate was placed in a 50°C sodium thiosulfate solution for chemical modification and grafting reaction for 8 min;

[0066] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0067] (7) After copper electroplating, the substrate was baked at 150°C for 60 minutes to remove moisture, and then cured at 190°C for 90 minutes to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0068] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1. The results are as follows: Figure 1 shown.

[0069] Example 4

[0070] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 120°C and 0.6 MPa in vacuum;

[0071] (2) After lamination, the samples were pre-cured at 100°C for 30 min and 180°C for 30 min.

[0072] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 60°C for 10 min.

[0073] (4) After fluffing, transfer to 80℃ potassium permanganate solution for oxidation treatment for 10 minutes;

[0074] (5) After oxidation, the substrate was placed in a 50°C sodium thiosulfate solution for chemical modification and grafting reaction for 8 min;

[0075] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0076] (7) After copper electroplating, the substrate was baked at 150°C for 60 min to remove moisture, and then cured at 190°C for 90 min to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0077] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1, and the results obtained were similar to those of Example 1.

[0078] Example 5

[0079] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 110°C and 0.7 MPa in vacuum;

[0080] (2) After lamination, the samples were pre-cured at 110°C for 40 min and 190°C for 40 min.

[0081] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 50°C for 20 minutes.

[0082] (4) After fluffing, transfer to a 70°C potassium permanganate solution for oxidation treatment for 15 minutes;

[0083] (5) After oxidation, the substrate was placed in a sodium thiosulfate solution at 40°C for 15 min for chemical modification and grafting reaction;

[0084] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0085] (7) After copper electroplating, the substrate was baked at 190°C for 60 min to remove moisture, and then cured at 190°C for 90 min to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0086] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1, and the results obtained were similar to those of Example 1.

[0087] Example 6

[0088] (1) Two epoxy-cyanate resin stacking films (purchased from Ajinomoto Co., Ltd., Japan) were fixed on the upper and lower sides of a core board (an epoxy resin composite material composed of epoxy resin and glass fiber, purchased from Shenzhen Liuxin Industrial Co., Ltd.), and then heat-pressed at 130°C and 0.5 MPa in vacuum;

[0089] (2) After lamination, the samples were pre-cured at 120°C for 20 min and 200°C for 20 min.

[0090] (3) After pre-curing, the sample was placed in a sodium carbonate solution to remove oil stains, and then ultrasonically washed and blown dry to complete the surface cleaning of the sample. The sample was then fluffed in a fluffing agent (2-(2-butoxyethoxy)ethanol) at 70°C for 5 minutes.

[0091] (4) After fluffing, transfer to a 90°C potassium permanganate solution for oxidation treatment for 5 minutes;

[0092] (5) After oxidation, the substrate was placed in a sodium thiosulfate solution at 60°C for 5 min for chemical modification and grafting reaction;

[0093] (6) After modification, the substrate was subjected to chemical copper plating and electroplating. The specific process was as follows: the modified substrate was placed in a chemical plating solution tank, left to stand at room temperature for 30 minutes, then rinsed with deionized water, and then transferred to an electroplating solution tank for electroplating at a voltage of 3 V and a current density of 1 asd for 60 minutes;

[0094] (7) After copper electroplating, the substrate was baked at 190°C for 60 min to remove moisture, and then cured at 190°C for 90 min to increase chemical crosslinking, thereby obtaining a surface-grafted modified substrate.

[0095] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1, and the results obtained were similar to those of Example 1.

[0096] Comparative Example 1

[0097] The method of Example 1 was followed, except that step (5) was not performed.

[0098] The interfacial bonding strength between the modified substrate and copper was tested according to the method of Example 1. The results are as follows: Figure 1 As shown (i.e., the curve represented by the control sample).

[0099] The foregoing description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be readily conceived by a person skilled in the art within the technical scope disclosed herein are intended to be encompassed within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A method for preparing a surface grafted modified substrate, characterized in that: The following steps are involved: The epoxy resin substrate is placed in a thiosulfate solution, and the epoxy groups on the surface of the epoxy resin substrate react with the thiosulfate to obtain the surface grafted modified substrate.

2. The preparation method according to claim 1, characterized in that The reaction temperature is 40-60° C. and the reaction time is 5-15 minutes.

3. The preparation method according to claim 1 or 2, characterized in that The thiosulfate includes one or more of sodium thiosulfate, potassium thiosulfate or ammonium thiosulfate.

4. The preparation method according to claim 1 or 2, characterized in that Before placing the epoxy resin substrate in the thiosulfate solution, the preparation method further comprises: placing the epoxy resin substrate in an oxidant solution for oxidation treatment; Preferably, the oxidant is one or more of potassium permanganate, hydrogen peroxide, peracetic acid, sodium dichromate, chromic acid, nitric acid, ammonium persulfate, sodium hypochlorite, sodium percarbonate, sodium perborate, and potassium perborate; the oxidation temperature is 70-90° C.; and the oxidation time is 5-15 min.

5. The preparation method according to claim 1 or 2, characterized in that The epoxy resin substrate includes a core board and an epoxy resin deposition film arranged on the upper and lower surfaces of the core board; the material of the epoxy resin deposition film is a mixture of high molecular epoxy resin and silica filler; the core board is a silicon substrate, a ceramic substrate, a glass substrate or an epoxy resin composite material composed of epoxy resin and glass fiber.

6. The preparation method according to claim 5, characterized in that The high molecular weight epoxy resin is epoxy-phenolic resin or epoxy-cyanate resin.

7. The preparation method according to claim 5, characterized in that The preparation method of the epoxy resin substrate comprises: Fixing the two epoxy resin deposition films on the upper and lower surfaces of the core plate respectively, and then performing a heat pressing process at a temperature of 110-130° C. and a vacuum state of 0.5-0.7 MPa; After hot pressing, the obtained samples were pre-cured at 100-120°C for 20-40 min and 180-200°C for 10-40 min. After pre-curing, clean the sample surface and then fluff it in a fluffing agent at 50-70°C for 5-20 minutes.

8. The preparation method according to claim 7, characterized in that The cleaning process includes: placing the sample in an alkaline solution to remove oil stains, then ultrasonically washing and drying; The bulking agent is one or more of 2-(2-butoxyethoxy)ethanol, dimethylformamide, dihydroxy diethyl butyl ether, and ethylene glycol.

9. The preparation method according to claim 1 or 2, characterized in that: After the reaction is completed, the preparation method further comprises: performing chemical plating and electroplating on the surface grafted modified substrate; baking; and curing.

10. A surface grafted modified substrate, characterized in that: The method is obtained by the preparation method according to any one of claims 1 to 9.

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