阅读说明：本技术 一种用石墨烯对陶瓷表面粗化的方法及覆铜板的制作方法 (Method for roughening ceramic surface by using graphene and manufacturing method of copper-clad plate ) 是由 黄明安 温淦尹 邓卫林 于 2020-12-24 设计创作，主要内容包括：本发明公开了一种用石墨烯对陶瓷表面粗化的方法及覆铜板的制作方法,所述用石墨烯对陶瓷表面粗化的方法包括以下步骤：将液相分散的石墨烯涂覆在陶瓷基材的表面上,而后挥发掉溶剂；将液碱涂覆在陶瓷基材的表面上；而后对陶瓷基材进行烘烤；然后对陶瓷基材进行超声波清洗,得到粗化后的陶瓷基材。本发明方法通过增加石墨烯对陶瓷表面进行保护后再粗化,使其表面形成微观的粗糙面,可大大提高陶瓷基材与金属覆盖层之间的结合力；并使利用该粗化后的陶瓷基材制作的覆铜板的结合力达到陶瓷基覆铜板的剥离强度要求。(The invention discloses a method for roughening a ceramic surface by using graphene and a manufacturing method of a copper-clad plate, wherein the method for roughening the ceramic surface by using graphene comprises the following steps: coating liquid-phase dispersed graphene on the surface of a ceramic substrate, and then volatilizing a solvent; coating liquid alkali on the surface of the ceramic substrate; then baking the ceramic substrate; and then carrying out ultrasonic cleaning on the ceramic substrate to obtain a roughened ceramic substrate. According to the method, the surface of the ceramic is protected by adding the graphene and then roughened, so that a microscopic rough surface is formed on the surface of the ceramic, and the binding force between the ceramic substrate and the metal covering layer can be greatly improved; and the bonding force of the copper-clad plate manufactured by the coarsened ceramic substrate can meet the peeling strength requirement of the ceramic-based copper-clad plate.)

1. A method for roughening a ceramic surface by using graphene is characterized by comprising the following steps:

s1, coating the graphene dispersed in the liquid phase on the surface of the ceramic substrate, and then volatilizing the solvent;

s2, coating liquid alkali on the surface of the ceramic substrate;

s3, baking the ceramic substrate;

and S4, carrying out ultrasonic cleaning on the ceramic substrate to obtain a roughened ceramic substrate.

2. The method for roughening the surface of ceramic according to claim 1, wherein the graphene is dispersed in the liquid phase at a concentration of 0.1-1.0% by mass in step S1.

3. The method for roughening the surface of ceramic according to claim 1, wherein in step S1, the particle size of graphene is 1 μm.

4. The method for roughening the surface of ceramic using graphene according to claim 1, wherein in step S1, the coating is performed by dip coating, roll coating, brush coating or spray coating.

5. The method for roughening the surface of ceramic with graphene according to claim 1, wherein in step S2, the liquid alkali is sodium hydroxide with a concentration of 30-50% by mass.

6. The method for roughening the surface of ceramic using graphene according to claim 1, wherein in step S2, the coating is performed by dip coating, roll coating, brush coating or spray coating.

7. The method for roughening the surface of ceramic with graphene according to claim 1, wherein in step S3, the ceramic substrate is baked at 320-600 ℃ for 10-30 min.

8. The method for roughening a ceramic surface using graphene according to claim 1, wherein the ultrasonic cleaning time is 10 minutes or more in step S4.

9. The manufacturing method of the copper-clad plate is characterized by comprising the following steps:

s10, cutting out the ceramic substrate roughened by the method according to any one of claims 1 to 8 according to the size of the jointed board;

s11, depositing a copper layer on the surface of the ceramic substrate through a copper deposition process;

and S12, thickening the thickness of the copper layer on the board surface by full-board electroplating to obtain the copper-clad board.

10. The method for manufacturing the copper-clad plate according to claim 9, wherein in step S12, the thickness of the copper layer on the plate surface is plated to 35 μm.

Technical Field

The invention relates to the technical field of graphene application and printed circuit board manufacturing, in particular to a method for roughening a ceramic surface by using graphene and a manufacturing method of a copper-clad plate.

Background

Graphene is a two-dimensional crystal material formed by tightly packing carbon atoms, and the special monoatomic layer structure of graphene determines that graphene has rich and novel physical properties.

Ceramic substrates are widely used as liners for power modules of semiconductor devices due to their advantages of low dielectric constant, excellent thermal conductivity, low coefficient of thermal expansion matching with chips, and the like.

The surface property of the ceramic is greatly different from that of the metal covering layer, so that the ceramic and the metal covering layer cannot be directly combined, in order to realize the combination of the ceramic and the metal covering layer, the surface of the ceramic is roughened by using a NaOH solution, a mixed acid solution and even a plasma bombardment technology, and the mechanical embedding force between the metal solder and the ceramic is enhanced, so that the problem of poor compatibility between the ceramic and a metal substrate is indirectly solved.

From the metallurgical point of view, the crystal extension, diffusion and bonding effects in the interaction between the ceramic and the surface metal covering layer are very weak, and in order to improve the bonding strength between the ceramic and the metal covering layer as much as possible, the surface of the ceramic matrix needs to be roughened, and the roughness and the contact area of the surface of the matrix are properly increased so as to obtain the ideal surface appearance and wetting property; with the demands for high performance, high reliability and the like of the circuit board, the bonding force between the ceramic and the surface metal covering layer needs to meet a certain peeling strength requirement, but the existing roughening method cannot provide good bonding force for the ceramic and the surface metal covering layer, and the roughening of the ceramic needs to be improved.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a method for roughening the surface of the ceramic by using graphene, wherein the surface of the ceramic is roughened after the graphene is added to protect the surface of the ceramic, so that a microscopic rough surface is formed on the surface of the ceramic, and the bonding force between a ceramic substrate and a metal covering layer can be greatly improved.

In order to solve the technical problem, the invention provides a method for roughening the surface of ceramic by using graphene, which comprises the following steps:

s1, coating the graphene dispersed in the liquid phase on the surface of the ceramic substrate, and then volatilizing the solvent to form a graphene coating on the surface of the ceramic substrate;

s2, coating liquid caustic soda on the surface of the graphene coating of the ceramic substrate;

s3, baking the ceramic substrate;

and S4, carrying out ultrasonic cleaning on the ceramic substrate to obtain a roughened ceramic substrate.

Further, in step S1, the mass percentage concentration of graphene in the liquid phase dispersion is 0.1 to 1.0%.

Further, in step S1, the particle size of the graphene is 1 μm.

Further, in step S1, the coating method is dip coating, roll coating, brush coating or spray coating.

Further, in step S2, the liquid caustic soda is sodium hydroxide with a mass percentage concentration of 30-50%.

Further, in step S2, the coating method is dip coating, roll coating, brush coating or spray coating.

Further, in step S3, the ceramic substrate is baked at 320-600 ℃ for 10-30 min.

Further, in step S4, the ultrasonic cleaning time is 10 minutes or more.

The invention also provides a manufacturing method of the copper-clad plate, which comprises the following steps:

s10, cutting out the ceramic substrate roughened by the method according to any one of claims 1 to 8 according to the size of the jointed board;

s11, depositing a copper layer on the surface of the ceramic substrate through a copper deposition process;

and S12, thickening the thickness of the copper layer on the board surface by full-board electroplating to obtain the copper-clad board.

Further, in step S12, the thickness of the copper layer on the board surface is plated to 35 μm.

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

according to the invention, the ceramic surface is protected by adding graphene and then roughened, and the graphene can be attached to the ceramic surface in a microscopic state by utilizing the microscopic lamellar structure and chemical inertia of the graphene, so that the ceramic particles are protected from being corroded by sodium hydroxide subjected to later roughening, and a microscopic rough surface is finally formed, so that the binding force between the ceramic substrate and the metal covering layer can be greatly improved, and the roughening method has the characteristics of simple implementation process, good roughening effect and low cost, and is easy to realize industrial production; the method has wide application range, and can be used on alumina ceramics, aluminum nitride ceramics and silicon nitride ceramics.

The copper clad laminate is prepared by forming the copper clad layer on the roughened ceramic substrate, so that the ceramic substrate and the metal covering layer have good bonding force, the bonding force meets the peeling strength requirement of the ceramic-based copper clad laminate, and the requirements of high performance and high reliability are met.

Drawings

FIG. 1 is an electron scanning microscope image of the surface of the original ceramic substrate in the example;

FIG. 2 is an SEM image of roughened ceramic substrate of example 1;

FIG. 3 is an SEM image of roughened ceramic substrate of example 2;

FIG. 4 is an SEM image of the backside of the copper layer stripped in example 3.

Detailed Description

In order to more fully understand the technical contents of the present invention, the technical solutions of the present invention will be further described and illustrated with reference to specific embodiments.

Example 1

In the method for roughening the ceramic surface by using graphene shown in this embodiment, the method for protecting the ceramic surface by using graphene sequentially includes the following processing steps:

(1) coating graphene: spraying graphene dispersed in a liquid phase on the surface of a ceramic substrate, volatilizing a solvent after coating until a formed liquid film does not drop, and adsorbing the graphene on the surface of the ceramic to form a graphene coating; the mass percentage concentration of graphene in liquid phase dispersion is 0.5%, and the average particle size of the graphene is 1 μm; the liquid phase dispersion graphene is uniformly dispersed in the solution, and the graphene is uniformly dispersed on the surface of the ceramic substrate in the solution volatilization process after coating, so that the graphene is dispersed in alcohol in the embodiment, and the volatility of the alcohol is utilized, so that the production efficiency is improved.

(2) Coating liquid alkali: and (2) immersing the ceramic substrate coated with the graphene into a sodium hydroxide solution with the mass percentage concentration of 50%, taking out the ceramic substrate, and draining, thereby coating the liquid caustic soda on the surface of the graphene coating of the ceramic substrate.

(3) High-temperature coarsening: and (3) putting the ceramic substrate into a muffle furnace for baking, wherein the temperature of the oven is 500 ℃, and the high temperature is kept for 30 minutes.

(4) Ultrasonic cleaning: cleaning graphene, caustic soda and reaction products on the surface of the ceramic substrate by using ultrasonic waves; the cleaning agent used in the ultrasonic cleaning was pure water, and the cleaning time was 30 minutes.

After ultrasonic cleaning, the surface of the ceramic substrate is observed by an electron microscope, the electron microscope image of which is shown in figure 2, and compared with the electron microscope image (shown in figure 1) of the surface of the original ceramic substrate, it can be seen that a plurality of tiny pits are formed on the surface of the ceramic particles after graphene and sodium hydroxide treatment, namely, a microscopic rough surface is finally formed, so that the bonding force between the ceramic substrate and the metal covering layer can be greatly improved.

In other embodiments, in the step (1), the mass percentage concentration of the graphene in the liquid phase dispersion may also be 0.1 to 1.0%.

In other embodiments, in step (1), the liquid-phase-dispersed graphene may be coated on the surface of the ceramic substrate by dip coating, roll coating or brush coating.

In other embodiments, in step (2), the liquid alkali may be applied to the surface of the ceramic substrate by spraying, rolling or brushing.

In other embodiments, in step (3), the oven temperature for high temperature roughening may be 320-600 ℃ for 10-30 min.

In other embodiments, in the step (4), the time for ultrasonic cleaning may be controlled to be more than 10 min.

Example 2

In the method for roughening the ceramic surface shown in this embodiment, graphene is not used for protecting the ceramic surface, and the method sequentially includes the following processing steps:

(1) coating liquid alkali: the ceramic substrate is immersed in a sodium hydroxide solution with a mass percent concentration of 50%, then the ceramic substrate is taken out and drained, and thereby the liquid caustic soda is coated on the surface of the ceramic substrate.

(2) High-temperature coarsening: and (3) putting the ceramic substrate into a muffle furnace for baking, wherein the temperature of the oven is 500 ℃, and the high temperature is kept for 30 minutes.

(3) Ultrasonic cleaning: cleaning the surface of the ceramic substrate with ultrasonic waves to remove caustic soda and reaction products; the cleaning agent used in the ultrasonic cleaning was pure water, and the cleaning time was 30 minutes.

After ultrasonic cleaning, the surface of the ceramic substrate is observed by an electron microscope, and an electron microscope image of the surface of the ceramic substrate is shown in fig. 3, and as can be seen by comparing with an electron microscope image (shown in fig. 1) of the surface of the original ceramic substrate, only pits are formed on the surface of the ceramic particles after sodium hydroxide treatment, and the depth and the number of the pits are far less than the effect (shown in fig. 2) of graphene protection and sodium hydroxide corrosion in the method described in example 1, so that the bonding force between the ceramic substrate and the metal covering layer is small.

Example 3

The manufacturing method of the copper-clad plate shown in the embodiment adopts the ceramic substrate roughened by the method described in the embodiment 1 as the intermediate substrate of the copper-clad plate, and sequentially comprises the following processing procedures:

(1) cutting: ceramic substrates roughened as described in example 1 were cut to panel size 520 x 620 mm.

(2) Copper deposition: depositing a copper layer on the surface of the ceramic substrate through a chemical copper deposition process, thereby depositing a chemical copper layer with the thickness of 0.2-0.4 μm on the surface of the ceramic substrate.

(3) Electroplating: then, the thickness of the copper layer on the board surface is thickened by full-board electroplating to the required thickness, and the copper-clad board is prepared; in one embodiment, the thickness of the copper layer is plated to 35 μm.

In other embodiments, when the bonding force between the electroplated copper layer and the ceramic substrate needs to be detected, the step (3) further comprises the following steps:

(4) and sticking an adhesive tape: and sticking an adhesive tape with the width of 3mm on the surface of the copper-clad plate.

(5) Etching: and then removing the copper layer without the protection of the adhesive tape by etching, thereby only reserving the copper layer line with the width of 3mm on the copper-clad plate.

(6) Stripping: and (4) lifting the copper layer on the copper-clad plate by using a nicking tool, and strongly stripping the copper layer from the ceramic substrate.

The back surface (the surface combined with the surface of the ceramic substrate) of the stripped copper sheet is observed by a scanning electron microscope, an electron microscope image of the copper sheet is shown as an attached figure 4, a plurality of ceramic particles are adhered to the stripped copper sheet, and the ceramic particles are stripped off together during stripping, so that the coarsening effect of the surface of the ceramic substrate is indirectly proved.

The technical solutions provided by the embodiments of the present invention are described in detail above, and the principles and embodiments of the present invention are explained herein by using specific examples, and the descriptions of the embodiments are only used to help understanding the principles of the embodiments of the present invention; meanwhile, for a person skilled in the art, according to the embodiments of the present invention, there may be variations in the specific implementation manners and application ranges, and in summary, the content of the present description should not be construed as a limitation to the present invention.