WO2016078432A1

WO2016078432A1 - Modified aluminium oxide composite material, copper-coated substrate and preparation method thereof

Info

Publication number: WO2016078432A1
Application number: PCT/CN2015/084011
Authority: WO
Inventors: 曾小亮; 孙蓉; 郭坤
Original assignee: 中国科学院深圳先进技术研究院
Priority date: 2014-11-18
Filing date: 2015-07-14
Publication date: 2016-05-26
Also published as: CN104371274B; CN104371274A

Abstract

Disclosed is a modified aluminium oxide composite material, comprising the following materials in parts by mass: 35-55 parts of modified aluminium oxide particles, 25-35 parts of reinforced fibers, 15-35 parts of a liquid crystal epoxy resin, 10-21 parts of a curing agent and 0.1-1 parts of an accelerant; the modified aluminium oxide particles are obtained by modifying aluminium oxide particles by a silane coupling agent. The modified aluminium oxide composite material comprises modified aluminium oxide particles, reinforced fibers and a liquid crystal epoxy resin. After the aluminium oxide particles are modified by the silane coupling agent, active chemical groups such as an amino group and a hydroxyl group are formed on the surface thereof, and the aluminium oxide particles are chemically bonded to the liquid crystal epoxy resin via active groups such as the amino group and the hydroxyl group formed on the surface, thus improving an interaction effect at an interface, reducing thermal resistance at the interface and reducing clustering. Also disclosed are a copper-coated substrate employing the above modified aluminium oxide composite material and preparation method thereof.

Description

Modified alumina composite material, copper-clad substrate and preparation method thereof

Technical field

The invention relates to the field of preparation of a copper-clad substrate, in particular to a modified alumina composite material, a copper-clad substrate using the modified alumina composite material and a preparation method thereof.

Background technique

The copper-clad substrate is a plate-like material obtained by immersing an electronic fiberglass cloth or other reinforcing material with a resin, and coating the copper foil on one or both sides and hot pressing. The copper-clad substrate mainly provides three functions of heat conduction, insulation and support for the chip, and is a key raw material for manufacturing printed circuit boards (PCBs). In recent years, electronic products are moving toward portable, miniaturized, lightweight, and multi-functional, and this market demand puts higher demands on copper-clad substrates.

Alumina is by far the most commonly used substrate material in the microelectronics industry because it is superior to ceramic particle silica commonly used in substrate materials in mechanical, thermal, and electrical properties. The alumina raw material is abundant, the price is low, the thermal stability is high, and the alumina is stable in an oxidation and reduction atmosphere up to 1925 ° C. The ideal thermal conductivity of alumina reaches 30 W/m·K, and the uniform addition of alumina particles to the copper-clad substrate can greatly improve the mechanical properties and thermal properties of the substrate material.

However, the alumina particles have a large specific surface area and a high surface energy, so that the alumina particles are easily aggregated, and the alumina is more difficult to be uniform in the polymer matrix due to the lower force between the alumina and the polymer. Distribution, the conventional copper-clad substrate containing alumina particles is prone to clustering.

Summary of the invention

Based on this, it is necessary to provide a copper-clad substrate which is less prone to clustering and a preparation method, and a modified alumina composite material which can be used for the copper-clad substrate.

A modified alumina composite material comprising 35 parts to 55 parts of modified alumina particles, 25 parts to 35 parts of reinforcing fibers, 15 parts to 35 parts of liquid crystal epoxy resin, 10 parts to 21 parts by mass fraction. Curing And 0.1 part to 1 part of a promoter;

The modified alumina particles are obtained by modifying silane coupling agent alumina particles, and the modified alumina particles have a particle diameter of 100 nm to 1000 nm.

In one embodiment, the silane coupling agent modifies the alumina particles as follows: the alumina particles are added to a solvent and ultrasonically dispersed, and the temperature is raised to 50° C. to 60° C., and the silane coupling is added. Then, the mixture is heated to 70 ° C for 4 h to 5 h, and after cooling, the filter residue is retained, and the filter residue is dried to be the modified alumina particles, wherein the silane coupling agent and the alumina particles are The mass ratio is 3:100.

In one embodiment, the silane coupling agent is γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane or γ-methacryloyloxyl Propyltrimethoxysilane.

In one embodiment, the reinforcing fibers are regularly cross-aligned in the X-Y axis direction.

In one embodiment, the reinforcing fibers are silicon carbide fibers.

In one embodiment, the silicon carbide fibers are composed of 80 to 120 monofilaments, each of which has a diameter of 12 μm to 13 μm.

In one embodiment, the liquid crystal epoxy resin is 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, bisphenol A diglycidyl ether, 4,4'-dihydroxybiphenyl At least one of diglycidyl ether and 4,4'-dihydroxybinaphthyl diglycidyl ether.

In one embodiment, the curing agent is at least one of 4,4'-dihydroxybiphenyl, 4,4'-diaminobiphenyl, and 4,4'-diaminodiphenyl sulfone.

In one embodiment, the liquid crystal epoxy resin is in an equal stoichiometric ratio to the curing agent.

In one embodiment, the promoter is at least one of triphenylphosphine, imidazole, and chromium acetylacetonate.

A copper-clad substrate comprising a first electrode layer, a dielectric layer and a second electrode layer which are sequentially stacked; wherein the material of the dielectric layer is the modified alumina composite material described above.

In one embodiment, the material of the first electrode layer is at least one of copper, brass, aluminum, and nickel, and the second electrode layer is at least one of copper, brass, aluminum, and nickel.

A method for preparing a copper-clad substrate comprises the following steps:

35 parts to 55 parts of modified alumina particles, 15 parts to 35 parts of liquid crystal epoxy resin, 10 parts to 21 parts of curing agent, and 0.1 parts to 1 part of a promoter are dissolved in an organic solvent according to a mass fraction. After mixing for 0.5h to 2h, a mixed solution is obtained;

25 parts to 35 parts of reinforcing fibers are arranged on the centrifugal film according to the mass fraction, and then the mixed solution is coated on the reinforcing fibers and baked at 60 ° C to 150 ° C for 10 min to 90 min to obtain a semi-cured sheet. ;as well as

The prepreg is placed between the first electrode layer and the second electrode layer, and then hot pressed at a temperature of from 120 ° C to 200 ° C under a pressure of 5 kgf / cm ² to 30 kgf / cm ² for 4 h to 10 h, and finally solidified. The copper clad substrate.

In one embodiment, the modified alumina particles are prepared by adding the alumina particles to a solvent for ultrasonic dispersion, heating to 50 ° C to 60 ° C, adding the silane coupling agent, followed by stirring and heating. The reaction is carried out at 70 ° C for 4 h to 5 h. After cooling, the filter residue is filtered and retained. After the filter residue is dried, the modified alumina particles are obtained. The mass ratio of the silane coupling agent to the alumina particles is 3: 100.

In one embodiment, the silane coupling agent is γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane or γ-methacryloyloxyl The propyltrimethoxysilane has a mass ratio of the silane coupling agent to the alumina particles of 3:100.

In one embodiment, the operation of arranging 25 to 35 parts of the reinforcing fibers on the centrifugal film is: 25 to 35 parts of the reinforcing fibers are regularly cross-aligned on the centrifugal film in the XY-axis direction, The reinforcing fiber is a silicon carbide fiber.

In one embodiment, the liquid crystal epoxy resin is 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, bisphenol A diglycidyl ether, 4,4'-dihydroxybiphenyl At least one of diglycidyl ether and 4,4'-dihydroxybinaphthyl diglycidyl ether;

The curing agent is at least one of 4,4'-dihydroxybiphenyl, 4,4'-diaminobiphenyl and 4,4'-diaminodiphenyl sulfone;

The liquid crystal epoxy resin and the curing agent are in an equal stoichiometric ratio.

In one embodiment, the centrifuge film is made of polyethylene terephthalate.

The modified alumina composite material comprises modified alumina particles, reinforcing fibers and liquid crystal epoxy resin, and the modified alumina particles are obtained by modifying the alumina particles with a silane coupling agent. The alumina particles are modified by a silane coupling agent to form an active chemical group such as an amino group or a hydroxyl group, and the alumina particles are chemically bonded to the liquid crystal epoxy resin through a reactive group such as an amino group or a hydroxyl group formed on the surface, thereby improving the interface. The interaction reduces the thermal resistance of the interface and reduces the cluster phenomenon. Compared with traditional composite materials, this modified alumina composite is not prone to clustering.

DRAWINGS

1 is a flow chart showing a method of manufacturing a copper clad substrate according to an embodiment;

2 is a SEM photograph of dispersion of alumina particles in Example 1 in an organic solvent;

3 is a SEM photograph of dispersion of γ-aminopropyltriethoxysilane-modified alumina particles prepared in Example 1 in an organic solvent;

Figure 4 is a cross-sectional electron micrograph of the prepreg obtained in Example 1;

Figure 5 is a cross-sectional electron micrograph of the prepreg obtained in Example 1.

detailed description

The method for producing the ferrite powder will be further described in detail below mainly with reference to the accompanying drawings and specific examples.

The modified alumina composite material according to one embodiment includes 35 parts to 55 parts of modified alumina particles, 25 parts to 35 parts of reinforcing fibers, 15 parts to 35 parts of liquid crystal epoxy resin, and 10 parts by mass. 21 parts of curing agent and 0.1 part to 1 part of accelerator.

The modified alumina particles are obtained by modifying the alumina particles with a silane coupling agent. The modified alumina particles may have a particle diameter of from 100 nm to 1000 nm.

In a preferred embodiment, the modified alumina particles have a particle size of 700 nm.

The silane coupling agent is γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane or γ-methacryloxypropyltrimethoxysilane.

The silane coupling agent can modify the alumina particles by adding the alumina particles to the solvent. The sound is dispersed, and the temperature is raised to 50 ° C to 60 ° C, then the silane coupling agent is added, and then the temperature is raised to 70 ° C for 4 h to 5 h. After cooling, the residue is filtered and retained, and the filter residue is dried and then modified alumina particles. Wherein the mass ratio of the silane coupling agent to the alumina particles was 3:100. The solvent may be anhydrous ethanol or xylene. The filter residue can be dried at a temperature of 120 ° C and the drying time can be 24 h.

The alumina particles are modified by a silane coupling agent to form an active chemical group such as an amino group or a hydroxyl group, and the alumina particles are chemically bonded to the liquid crystal epoxy resin through a reactive group such as an amino group or a hydroxyl group formed on the surface, thereby improving the interface. The interaction reduces the thermal resistance of the interface and reduces the cluster phenomenon.

The reinforcing fibers are regularly arranged in the X-Y axis direction, have good thermal conductivity and mechanical properties, and improve the overall performance of the modified alumina composite.

The reinforcing fibers may be silicon carbide fibers. The silicon carbide fiber is composed of 80 to 120 monofilaments, and each of the monofilaments has a diameter of 12 μm to 13 μm.

The silicon carbide fiber acts as a heat conduction bridge in the modified alumina composite material, and enhances the connection between the modified alumina particles and the modified alumina particles and the modified alumina particles and the silicon carbide fibers, to a large extent Forming a thermally conductive network structure or a thermally conductive chain.

In the present embodiment, each of the monofilaments of the silicon carbide fibers has a tensile strength of 2 GPa and a modulus of 150 GPa.

The liquid crystal epoxy resin has a large rigid biphenyl structure or a naphthalene structure with a large aspect ratio, and has a large improvement in thermal properties, mechanical properties and dielectric properties compared with ordinary epoxy resins or BT resins; for example, long diameter The larger rigid structure can effectively suppress the scattering of phonons and increase the mean free path of phonons, so that its thermal conductivity is significantly improved.

Specifically, the liquid crystal epoxy resin is selected from the group consisting of 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, bisphenol A diglycidyl ether, 4,4'-dihydroxybiphenyl diglycidyl ether And at least one of 4,4'-dihydroxybinaphthyl diglycidyl ether.

The curing agent may be at least one of 4,4'-dihydroxybiphenyl, 4,4'-diaminobiphenyl, and 4,4'-diaminodiphenyl sulfone.

In the present embodiment, the liquid crystal epoxy resin and the curing agent are in an equal stoichiometric ratio, that is, both the liquid crystal epoxy resin and the curing agent react exactly.

In this embodiment, the sum of the mass of the modified alumina and the liquid crystal epoxy tree and the modified alumina composite The ratio of the total mass of the material was 7:10.

The promoter is at least one of triphenylphosphine, imidazole and chromium acetylacetonate.

A copper clad substrate according to an embodiment includes a first electrode layer, a dielectric layer, and a second electrode layer which are sequentially laminated.

The material of the dielectric layer is the modified alumina composite described above.

The material of the first electrode layer is at least one of copper, brass, aluminum, and nickel. The material of the second electrode layer is at least one of copper, brass, aluminum, and nickel.

The thickness of the first electrode layer is 10 μm to 35 μm, and the thickness of the second electrode layer is 10 μm to 35 μm.

The method for preparing the above copper-clad substrate shown in FIG. 1 includes the following steps:

S10. Dissolving 35 parts to 55 parts of modified alumina particles, 15 parts to 35 parts of liquid crystal epoxy resin, 10 parts to 21 parts of curing agent, and 0.1 parts to 1 part of the accelerator in an organic solvent according to the mass fraction. In the middle, the mixed solution is obtained after ultrasonication for 0.5 h to 2 h.

The organic solvent may be 2-butanone or acetone.

The silane coupling agent may modify the alumina particles by adding the alumina particles to the solvent and ultrasonically dispersing, heating to 50 ° C to 60 ° C, adding a silane coupling agent, and then heating to 70 ° C for 4 h to 5 h. After cooling, the filter residue is filtered and retained, and the filter residue is dried to be a modified alumina particle. Among them, silane coupling agent The mass ratio to the alumina particles was 3:100. The solvent may be anhydrous ethanol or xylene. The filter residue can be dried at a temperature of 120 ° C and the drying time can be 24 h.

S20, arranging 25 parts to 35 parts of reinforcing fibers on the centrifugal film according to the mass fraction, and then coating the mixed solution obtained in S10 on the reinforcing fibers and baking at 60 ° C to 150 ° C for 10 min to 90 min, to be cooled until After centrifugation, the centrifuge film was peeled off to obtain a prepreg.

The material of the centrifugal film may be polyethylene terephthalate. The centrifugal film of the polyethylene terephthalate material is easily peeled off when a semi-cured sheet is obtained because of its small surface tension.

Specifically, in S20, 25 to 35 parts of reinforcing fibers are regularly arranged in a crosswise arrangement on the centrifugal film in the X-Y axis direction.

Silicon carbide fiber acts as a heat-conducting bridge in the modified alumina composite, enhancing the modified oxidation The bonding between the aluminum particles and the modified alumina particles and the modified alumina particles and the silicon carbide fibers largely forms a thermally conductive network structure or a thermally conductive chain.

S30, placing the prepreg obtained in S20 between the first electrode layer and the second electrode layer, followed by hot pressing at a temperature of 120 ° C to 200 ° C and a pressure of 5 kgf / cm ² to 30 kgf / cm ² for 4 h to 10 h, and finally Curing to obtain a copper clad substrate.

The curing operation may be: curing at 150 ° C, 180 ° C, 220 ° C for 2 h.

After testing, the dielectric layer of the copper-clad substrate prepared by the method for preparing the copper-clad substrate has a radial thermal conductivity of 0.701 to 1.004 W/m·K and an axial thermal conductivity of 1.325 to 1.526 W/m·K. The transformation temperature is 170 to 180 °C.

The material of the dielectric layer of the copper-clad substrate prepared by the preparation method of the copper-clad substrate is a modified alumina composite material, and the modified alumina composite material comprises modified alumina particles, reinforcing fibers and liquid crystal epoxy resin, and is modified. The alumina particles are obtained by modifying the alumina particles with a silane coupling agent. The alumina particles are modified by a silane coupling agent to form an active chemical group such as an amino group or a hydroxyl group, and the alumina particles are chemically bonded to the liquid crystal epoxy resin through a reactive group such as an amino group or a hydroxyl group formed on the surface, thereby improving the interface. The interaction reduces the thermal resistance of the interface and reduces the cluster phenomenon.

The following is a specific embodiment. In the embodiment, the ball mill selects a ball mill 50kg ball mill made by Meizhou Huafeng, the laser particle size analyzer is Malvern MS3000 laser particle size analyzer, the specific surface area analyzer is ASAP2020 specific surface area tester, and the thermal conductivity tester is Hot Disk TPS2500s thermal analyzer. The glass transition temperature tester is a TA Q20 differential scanning calorimeter, and the scanning electron microscope is FEI's Nova Nano SEM 450.

Example 1

(1) Preparation of γ-aminopropyltriethoxysilane-modified alumina.

First, the alumina particles were dried at 110 ° C for 4 h. After cooling to room temperature, 15.0 g of alumina particles having a particle diameter of 700 nm and 50 mL of xylene were weighed into a three-necked flask and ultrasonically dispersed for 10 min, and then placed in an oil bath, magnetically stirred. The solution was warmed to 90 °C. 1.0 g of the surface modifier γ-aminopropyltriethoxysilane was added dropwise with a dropper, and the mixture was heated to 115 ° C after the dropwise addition, and magnetic stirring was continued for 6 hours.

The mixed solution was cooled, poured into a suction funnel while hot, and the sample obtained by suction filtration was washed with absolute ethanol for several times, and dried in a vacuum drying oven at 110 ° C for 12 h to obtain surface modification of γ-aminopropyltriethoxysilane. Alumina.

2 and 3 are SEM photographs of the alumina particles in Example 1 and the γ-aminopropyltriethoxysilane-modified alumina particles prepared in Example 1 dispersed in an organic solvent, respectively.

It can be seen from Fig. 2 that the alumina particles before modification tend to form clusters in an organic solvent, and the dispersibility is poor. Mainly because the alumina particles have a small specific surface area and a large surface energy, the alumina particles are easily combined into a block.

As can be seen from Fig. 3, the γ-aminopropyltriethoxysilane-modified alumina particles are substantially monodisperse and have little agglomeration. Mainly because the surface of the modified alumina particles is charged, the dispersion of the γ-aminopropyltriethoxysilane-modified alumina particles is better due to the charge interaction.

(2) Preparation of a prepreg.

2.60 g of 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, 1.40 g of 4,4'-diaminodiphenyl sulfone and 20.00 mg of triphenylphosphine were stirred and mixed at 180 ° C to maintain The reaction was carried out at 180 ° C for 30 min to obtain an amber viscous transparent epoxy resin composite.

The obtained 4.00 g epoxy resin composite and 4.00 g of γ-aminopropyltriethoxysilane surface-modified alumina were added to 4.50 g of 2-butanone solvent, and stirred by ultrasonic vibration for 2 hours. Mix well and obtain a mixed solution.

The mixed solution prepared above was applied by a bar coating method to silicon carbide fibers which were regularly arranged in a crosswise arrangement in the X-Y plane. It was baked in a blast oven at 130 ° C for 120 minutes to volatilize the solvent to obtain a prepreg. In the prepreg, the total mass percentage of the alumina and liquid crystal epoxy composites was 70%.

4 and 5 are cross-sectional electron micrographs of the prepreg obtained in Example 1.

4 is an electron micrograph of a liquid crystal epoxy resin coated longitudinally arranged silicon carbide fiber. As can be seen from FIG. 4, the modified alumina particles are uniformly dispersed in the liquid crystal epoxy resin, and the modified alumina particles are closely adhered. On the surface of silicon carbide fibers.

FIG. 5 is an electron micrograph of a silicon carbide fiber coated with a liquid crystal epoxy resin in a radial arrangement. As can be seen from FIG. 5, the liquid crystal epoxy resin has a good overall coating effect and has fewer defects, and the silicon carbide fiber fully functions. The function of the heat-conducting bridge enhances the connection between the modified alumina particles and the modified alumina particles and between the modified alumina particles and the silicon carbide fibers, and forms a heat-conductive network structure or a heat-conducting chain to a large extent.

(3) Preparation of a copper clad substrate.

First, two copper foils with a thickness of 40 μm were washed with a 15 wt% hydrochloric acid solution, and then the two copper foils were ultrasonically cleaned in acetone for 10 min, then ultrasonically cleaned in absolute ethanol for 10 min, and 60 in an oven. Drying at ° C gives a clean, dry first electrode layer and a second electrode layer.

After the two prepregs are overlapped, the silicon carbide fibers of the two are closely adhered, and placed between the first electrode layer and the second electrode layer, and hot pressed at 150 ° C and a pressure of 5 kgf / cm ^{2 in} a vacuum press. After 3 hours, finally, in a blast oven, curing at 150 ° C, 180 ° C, 220 ° C for 2 h, respectively, to obtain a copper-clad substrate.

The prepared copper-clad substrate comprises a first electrode layer, a dielectric layer and a second electrode layer which are sequentially stacked, wherein the first electrode layer and the second electrode layer are both copper foil sheets having a thickness of 40 μm, and the dielectric layer is two prepregs. Composition, the prepreg has a thickness of 500 microns.

After the test, it was found that the copper-clad substrate prepared in Example 1 had a radial thermal conductivity of 0.701 W/m·K, an axial thermal conductivity of 1.325 W/m·K, and a glass transition temperature of 175° C.

Example 2

The preparation method is basically the same as that in the first embodiment, except that the curing agent used in the step (2) is 4,4'-dihydroxybiphenyl, stirred and mixed uniformly at 130 ° C, and maintained at a temperature of 130 ° C for 30 min to obtain amber viscous. A transparent epoxy resin composite.

The prepared copper-clad substrate comprises a first electrode layer, a dielectric layer and a second electrode layer which are sequentially laminated, wherein the first electrode layer and the second electrode layer are both copper foil sheets having a thickness of 40 μm, and the dielectric layer is composed of two prepregs Composition, thickness is 500 microns.

After testing, it was found that the substrate material had a radial thermal conductivity of 0.876 W/m·K, an axial thermal conductivity of 1.358 W/m·K, and a glass transition temperature of 130 ° C.

Example 3

The preparation method is basically the same as that of Example 1, except that step (2) adds 5.60 g (55 parts) of γ-aminopropyltriethoxysilane-containing alumina and 2.40 g of epoxy resin system to 4.50 g. The 2-butanone solvent was stirred by an ultrasonic vibration method for 2 hours, and uniformly mixed to obtain an alumina composite material.

The prepared copper-clad substrate comprises a first electrode layer, a dielectric layer and a second electrode layer which are sequentially stacked, wherein the first electrode layer and the second electrode layer are both copper foil sheets having a thickness of 40 μm, and the dielectric layer is composed of two prepregs. Composition, thickness is 500 microns.

After testing, it was found that the substrate material had a radial thermal conductivity of 1.004 W/m·K, an axial thermal conductivity of 1.526 W/m·K, and a glass transition temperature of 180 ° C.

Comparative example 1

The preparation method was the same as in Example 1, except that the step (2) was applied to the glass fiber cloth.

The prepared copper-clad substrate comprises a first electrode layer, a dielectric layer and a second electrode layer which are sequentially stacked, wherein the first electrode layer and the second electrode layer are both copper foil sheets having a thickness of 40 μm, and the dielectric layer is composed of two prepregs. The thickness is 100 microns.

After testing, it was found that the substrate material had a radial thermal conductivity of 0.777 W/m·K, an axial thermal conductivity of 0.803 W/m·K, and a glass transition temperature of 175 ° C.

Comparative example 2

The preparation method was the same as in Example 2 except that the same amount of unmodified alumina was added in the step (2).

The prepared copper-clad substrate comprises a first electrode layer, a dielectric layer and a second electrode layer which are sequentially stacked, wherein the first electrode layer and the second electrode layer are both copper foil sheets having a thickness of 40 μm, and the dielectric layer is composed of two prepregs. Composition, thickness is 500 microns. The substrate material has a radial thermal conductivity of 0.592 W/m·K, and the axis guide The thermal coefficient was 0.888 W/m·K and the glass transition temperature was 175 °C.

The above-mentioned embodiments are merely illustrative of several embodiments of the present invention, and the description thereof is more specific and detailed, but is not to be construed as limiting the scope of the invention. It should be noted that a number of variations and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of the invention should be determined by the appended claims.

Claims

A modified alumina composite material comprising 35 parts to 55 parts of modified alumina particles, 25 parts to 35 parts of reinforcing fibers, 15 parts to 35 parts of liquid crystal epoxy resin according to a mass fraction, 10 Parts to 21 parts of curing agent and 0.1 part to 1 part of accelerator;

The modified alumina particles are obtained by modifying silane coupling agent alumina particles, and the modified alumina particles have a particle diameter of 100 nm to 1000 nm.
The modified alumina composite according to claim 1, wherein the silane coupling agent modifies the alumina particles as follows: the alumina particles are added to a solvent and ultrasonically dispersed, and the temperature is raised to After the temperature is between 50 ° C and 60 ° C, the silane coupling agent is added, and then the temperature is raised to 70 ° C for 4 h to 5 h. After cooling, the residue is filtered and retained. After the filter residue is dried, the modified alumina particles are obtained. The mass ratio of the silane coupling agent to the alumina particles was 3:100.
The modified alumina composite according to claim 1 or 2, wherein the silane coupling agent is γ-aminopropyltriethoxysilane or γ-(2,3-epoxypropoxy) Propyltrimethoxysilane or γ-methacryloxypropyltrimethoxysilane.
The modified alumina composite according to claim 1, wherein the reinforcing fibers are regularly arranged in a crosswise direction in the X-Y axis direction.
The modified alumina composite according to claim 1 or 4, wherein the reinforcing fibers are silicon carbide fibers.
The modified alumina composite according to claim 5, wherein the silicon carbide fibers are composed of 80 to 120 monofilaments each having a diameter of 12 μm to 13 μm.
The modified alumina composite material according to claim 1, wherein the liquid crystal epoxy resin is 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, bisphenol A condensed water At least one of glyceryl ether, 4,4'-dihydroxybiphenyl diglycidyl ether and 4,4'-dihydroxybinaphthyl diglycidyl ether.
The modified alumina composite according to claim 1, wherein the curing agent is 4,4'-dihydroxybiphenyl, 4,4'-diaminobiphenyl and 4,4'-diamino group. At least one of diphenyl sulfone.
The modified alumina composite according to claim 1, 7 or 8, wherein the liquid crystal epoxy resin and the curing agent are in an equivalent stoichiometric ratio.
The modified alumina composite according to claim 1, wherein the accelerator is at least one of triphenylphosphine, imidazole and chromium acetylacetonate.
A copper-clad substrate comprising a first electrode layer, a dielectric layer and a second electrode layer laminated in sequence; wherein the material of the dielectric layer is modified oxidation according to any one of claims 1 to 10. Aluminum composite.
The copper-clad substrate according to claim 11, wherein the material of the first electrode layer is at least one of copper, brass, aluminum and nickel, and the second electrode layer is copper, brass, At least one of aluminum and nickel.
A method for preparing a copper-clad substrate, comprising the steps of:

35 parts to 55 parts of modified alumina particles, 15 parts to 35 parts of liquid crystal epoxy resin, 10 parts to 21 parts of curing agent, and 0.1 parts to 1 part of a promoter are dissolved in an organic solvent according to a mass fraction. After mixing for 0.5h to 2h, a mixed solution is obtained;

25 parts to 35 parts of reinforcing fibers are arranged on the centrifugal film according to the mass fraction, and then the mixed solution is coated on the reinforcing fibers and baked at 60 ° C to 150 ° C for 10 min to 90 min, to be cooled to room temperature. After the centrifugal film is peeled off to obtain a prepreg;

The prepreg is placed between the first electrode layer and the second electrode layer, and then hot pressed at a temperature of from 120 ° C to 200 ° C under a pressure of 5 kgf / cm 2 to 30 kgf / cm 2 for 4 h to 10 h, and finally solidified. The copper clad substrate.
The method for preparing a copper-clad substrate according to claim 13, wherein the preparation process of the modified alumina particles is as follows: the alumina particles are added to a solvent and ultrasonically dispersed, and the temperature is raised to 50 ° C to 60 ° C. Thereafter, the silane coupling agent is added, followed by stirring to a temperature of 70 ° C for 4 h to 5 h, and after cooling, filtering and retaining the filter residue, the filter residue is dried to be the modified alumina particles, wherein the silane coupling agent The mass ratio to the alumina particles was 3:100.
The method for preparing a copper-clad substrate according to claim 14, wherein the silane coupling agent is γ-aminopropyltriethoxysilane or γ-(2,3-epoxypropoxy)propyl group. Trimethoxysilane or γ-methacryloxypropyltrimethoxysilane, the mass ratio of the silane coupling agent to the alumina particles is 3:100.
The method for preparing a copper-clad substrate according to claim 13, wherein 25 to 35 The reinforcing fibers are arranged on the centrifugal film in such a manner that 25 to 35 parts of the reinforcing fibers are regularly cross-aligned on the centrifugal film in the X-Y axis direction, and the reinforcing fibers are silicon carbide fibers.
The method of producing a copper-clad substrate according to claim 16, wherein the silicon carbide fiber is composed of 80 to 120 monofilaments, and each of the monofilaments has a diameter of 12 μm to 13 μm.
The method for preparing a copper-clad substrate according to claim 13, wherein the liquid crystal epoxy resin is 3,3',5,5'-tetramethylbiphenyl diglycidyl ether, bisphenol A condensed water At least one of glyceryl ether, 4,4'-dihydroxybiphenyl diglycidyl ether and 4,4'-dihydroxybinaphthyl diglycidyl ether;

The curing agent is at least one of 4,4'-dihydroxybiphenyl, 4,4'-diaminobiphenyl and 4,4'-diaminodiphenyl sulfone;

The liquid crystal epoxy resin and the curing agent are in an equal stoichiometric ratio.
The method of producing a copper-clad substrate according to claim 13, wherein the material of the centrifugal film is polyethylene terephthalate.