阅读说明：本技术 高热稳定、高尺寸稳定微波复合介质基板及制备方法 (High-heat-stability and high-size-stability microwave composite dielectric substrate and preparation method thereof ) 是由 王丽婧 金霞 武聪 贾倩倩 *** 张立欣 韩伏龙 高枢建 于 2019-11-01 设计创作，主要内容包括：本发明涉及一种具有高热稳定、高尺寸稳定微波复合介质基板及制备工艺,各种原材料的质量分数配比为:40-80 wt%的无机填料粉末、1-10 wt%的石英纤维、10-55 wt%的含氟树脂聚合物体系；制备方法：过筛石英纤维；改性处理石英纤维；改性处理无机填料粉末；石英纤维用表面活性剂溶液分散,处理后的原料混合搅拌、絮凝、沉降、过滤、烘干、等静压成型、双面覆铜箔、烧结、热处理。产品性能优良,制备工艺简单,环境友好,原料来源方便,有利于实现工业化生产。(The invention relates to a microwave composite medium substrate with high thermal stability and high dimensional stability and a preparation process thereof, wherein the mass fraction ratio of various raw materials is 40-80 wt% of inorganic filler powder, 1-10 wt% of quartz fiber and 10-55wt% of fluorine-containing resin polymer system; the preparation method comprises the following steps: sieving quartz fiber; modifying the quartz fiber; modifying inorganic filler powder; dispersing quartz fiber with surfactant solution, mixing the treated materials, stirring, flocculating, settling, filtering, stoving, isostatic pressing, covering with copper foil, sintering and heat treatment. The product has the advantages of excellent performance, simple preparation process, environmental protection, convenient raw material source and contribution to realizing industrial production.)

1. A high thermal stability, high stable microwave composite medium base plate of size which characterized in that: the weight percentage ratio of the raw materials is 40-80 wt% of inorganic filler powder, 1-10 wt% of quartz fiber and 10-55wt% of fluorine-containing resin polymer system.

2. A highly thermally stable, highly dimensionally stable microwave composite dielectric substrate as recited in claim 1, wherein: the inorganic filler powder is selected from one or more of silicon dioxide powder, aluminum oxide powder, zinc oxide powder, magnesium oxide powder, calcium sulfate powder and boron nitride powder, and at least comprises silicon dioxide powder, and the particle size D50 of the powder is 10-20 mu m.

3. A highly thermally stable, highly dimensionally stable microwave composite dielectric substrate as recited in claim 1, wherein: the fluorine-containing resin polymer system is selected from one or more of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer and ethylene-chlorotrifluoroethylene copolymer, and at least comprises polytetrafluoroethylene.

4. A highly thermally stable, highly dimensionally stable microwave composite dielectric substrate as claimed in any one of claims 1 to 3 wherein: the mass fraction ratio of various raw materials is as follows: 56 wt% of silica powder, 5wt% of alumina powder, 5wt% of zinc oxide powder, 4.0 wt% of quartz fiber, 25 wt% of polytetrafluoroethylene, 5wt% of ethylene-tetrafluoroethylene copolymer.

5. A method for preparing a high-thermal-stability and high-dimensional-stability microwave composite dielectric substrate according to claim 1, comprising the following steps: firstly, weighing various raw materials according to the mass fraction ratio of the raw materials, and secondly, weighing the following auxiliary agents according to the proportion: coupling agent accounting for 0.1 to 5.0 weight percent of the total mass of the inorganic filler powder and the quartz fiber formula, surfactant accounting for 0.1 to 1.5 weight percent of the mass of the quartz fiber formula, flocculating agent accounting for 0.1 to 2.0 weight percent of the mass of the inorganic filler powder, and proper amount of formic acid, absolute ethyl alcohol and deionized water;

the method comprises the following steps:

sieving quartz fibers to obtain short-cut quartz fibers in a 100-mesh and 300-mesh screen;

secondly, respectively carrying out surface modification treatment on the chopped quartz fibers with different lengths by using a coupling agent: dissolving a coupling agent accounting for 0.1-5.0 wt% of the formula mass of the quartz fiber in an absolute ethyl alcohol solution, wherein the volume ratio of the coupling agent to the absolute ethyl alcohol is 1:2-1:8, the stirring speed is 120 plus materials for 180r/min, the stirring is carried out for 20-60 min, the stirring is carried out until the coupling agent is completely dissolved, the quartz fibers with different lengths are respectively added into and immersed in a reaction kettle containing the ethanol solution of the coupling agent, the reaction kettle is placed in an ultrasonic machine for ultrasonic treatment at 40-80 ℃ for 30-180 min, the modified quartz fibers in the reaction kettle are poured into filter cloth after the treatment is finished, the redundant solution is filtered, and the reaction kettle is placed in an oven at 85-125 ℃ for drying treatment for 2-10 h;

thirdly, carrying out surface modification treatment on the inorganic filler powder by using a coupling agent: firstly, dissolving formic acid in absolute ethyl alcohol, wherein the volume ratio of the formic acid to the absolute ethyl alcohol is 1:2-1: 10; dissolving 0.1-5.0 wt% of coupling agent of the formula weight of the inorganic filler powder in formic acid-absolute ethyl alcohol solution, wherein the volume ratio of the coupling agent to the formic acid-absolute ethyl alcohol solution is 1:2-1:8, the stirring speed is 120-180r/min, and the stirring is carried out for 20-60 min until the coupling agent is completely dissolved, thus preparing coupling agent mixed solution; then pouring the weighed inorganic filler powder into the coupling agent mixed liquid, stirring for 60-180min at the temperature of 35-65 ℃ and the stirring speed of 150-250r/min, and finally drying the modified inorganic filler powder in a drying oven at the temperature of 65-125 ℃ for 2-10 h;

adding a surfactant into a certain amount of deionized water, stirring at the speed of 100-;

sequentially adding the fluorine-containing resin polymer, the modified inorganic filler powder and the short-cut quartz fiber surfactant mixed solution into a reaction kettle, and fully stirring for 60-240 min at the temperature of 30-80 ℃ and the stirring speed of 100-;

adding flocculant in 0.1-2.0 wt% of inorganic stuffing powder to settle solid components in the composite system, pumping out water to obtain settled composite, and drying in a drying oven at 90-130 deg.c for 2-10 hr;

seventhly, forming the compound powder obtained by the step II by adopting an isostatic pressing mode: firstly, encapsulating powder in a mould, sealing, then placing the mould into a high-pressure cylinder of isostatic pressing equipment, keeping the pressure for 10-60min at the temperature of 50-150 ℃ for 2-10min until the maximum pressure is 1-30 MPa, then removing the pressure within 2-20min, and taking out the mould to obtain a green chip;

eighthly, covering copper foils on two sides of the obtained raw substrate, and carrying out hot-pressing sintering at the temperature of 80-390 ℃ and the pressure of 4-20 MPa for 120-240 min to obtain a microwave composite dielectric substrate;

ninthly, carrying out heat treatment on the obtained microwave composite dielectric substrate at the temperature of 80-250 ℃ and under the pressure of 2-10 MPa for 60-240 min to obtain a microwave composite dielectric substrate product with high thermal stability and high dimensional stability;

wherein, the coupling agent is selected from one or more of silane coupling agent, titanate coupling agent and zirconate coupling agent, and at least comprises silane coupling agent, and the dosage is 0.1-5.0 wt% of the total mass of inorganic filler powder and quartz fiber formula; the surfactant is one or more selected from polyethylene glycol laurate, polyhydroxy laurate and polyhydroxy propyl laurate, and the dosage of the surfactant is 0.1-1.5wt% of the mass of the quartz fiber formula.

Technical Field

The invention relates to the technical field of microwave composite dielectric substrates, in particular to a microwave composite dielectric substrate with high thermal stability and high dimensional stability and a preparation process thereof.

Background

With the rapid development of electronic industry technology, copper-clad plate products with general performance cannot meet the requirement of electronic installation high-density interconnection which is developed at a high speed in recent years, and microwave composite dielectric substrates with high performance are developed greatly in recent years.

At present, along with the development direction of miniaturization, digitalization, multifunctionalization and high reliability of electronic products, copper-clad plates serving as main carriers of electronic components have higher and higher integration level and finer circuit arrangement, and heat generated during working operation is increased, so that higher requirements on thermal stability and dimensional stability of circuit substrates are provided. Therefore, in order to ensure fast and stable signal transmission, the microwave composite dielectric substrate used as a component carrier needs to have not only lower dielectric loss and uniform dielectric constant, but also lower thermal change rate of the dielectric constant, and smaller thermal expansion coefficient and dimensional stability, so as to ensure the processing reliability and the use stability of the plate.

Disclosure of Invention

The invention aims to solve the technical problem of providing a microwave composite medium substrate with high thermal stability and high dimensional stability and a preparation method thereof.

The technical scheme of the invention is a microwave composite medium substrate with high thermal stability and high dimensional stability, which is characterized in that: the weight percentage ratio of the raw materials is 40-80 wt% of inorganic filler powder, 1-10 wt% of quartz fiber and 10-55wt% of fluorine-containing resin polymer system.

A preparation method of a microwave composite medium substrate with high thermal stability and high dimensional stability is characterized by comprising the following steps: coupling agent accounting for 0.1 to 5.0 weight percent of the total mass of the inorganic filler powder and the quartz fiber formula, surfactant accounting for 0.1 to 1.5 weight percent of the mass of the quartz fiber formula, flocculating agent accounting for 0.1 to 2.0 weight percent of the mass of the inorganic filler powder, and proper amount of formic acid, absolute ethyl alcohol and deionized water;

the method comprises the following steps:

sieving quartz fibers to obtain short-cut quartz fibers in a 100-mesh and 300-mesh screen;

secondly, respectively carrying out surface modification treatment on the chopped quartz fibers with different lengths by using a coupling agent: dissolving a coupling agent accounting for 0.1-5.0 wt% of the formula mass of the quartz fiber in an absolute ethyl alcohol solution, wherein the volume ratio of the coupling agent to the absolute ethyl alcohol is 1:2-1:8, the stirring speed is 120 plus materials for 180r/min, the stirring is carried out for 20-60 min, the stirring is carried out until the coupling agent is completely dissolved, the quartz fibers with different lengths are respectively added into and immersed in a reaction kettle containing the ethanol solution of the coupling agent, the reaction kettle is placed in an ultrasonic machine for ultrasonic treatment at 40-80 ℃ for 30-180 min, the modified quartz fibers in the reaction kettle are poured into filter cloth after the treatment is finished, the redundant solution is filtered, and the reaction kettle is placed in an oven at 85-125 ℃ for drying treatment for 2-10 h;

thirdly, carrying out surface modification treatment on the inorganic filler powder by using a coupling agent: firstly, dissolving formic acid in absolute ethyl alcohol, wherein the volume ratio of the formic acid to the absolute ethyl alcohol is 1:2-1: 10; dissolving 0.1-5.0 wt% of coupling agent of the formula weight of the inorganic filler powder in formic acid-absolute ethyl alcohol solution, wherein the volume ratio of the coupling agent to the formic acid-absolute ethyl alcohol solution is 1:2-1:8, the stirring speed is 120-180r/min, and the stirring is carried out for 20-60 min until the coupling agent is completely dissolved, thus preparing coupling agent mixed solution; then pouring the weighed inorganic filler powder into the coupling agent mixed liquid, stirring for 60-180min at the temperature of 35-65 ℃ and the stirring speed of 150-250r/min, and finally drying the modified inorganic filler powder in a drying oven at the temperature of 65-125 ℃ for 2-10 h;

adding a surfactant into a certain amount of deionized water, stirring at the speed of 100-;

sequentially adding the fluorine-containing resin polymer, the modified inorganic filler powder and the short-cut quartz fiber surfactant mixed solution into a reaction kettle, and fully stirring for 60-240 min at the temperature of 30-80 ℃ and the stirring speed of 100-;

adding flocculant in 0.1-2.0 wt% of inorganic stuffing powder to settle solid components in the composite system, pumping out water to obtain settled composite, and drying in a drying oven at 90-130 deg.c for 2-10 hr;

seventhly, forming the compound powder obtained by the step II by adopting an isostatic pressing mode: firstly, encapsulating powder in a mould, sealing, then placing the mould into a high-pressure cylinder of isostatic pressing equipment, keeping the pressure for 10-60min at the temperature of 50-150 ℃ for 2-10min until the maximum pressure is 1-30 MPa, then removing the pressure within 2-20min, and taking out the mould to obtain a green chip;

eighthly, covering copper foils on two sides of the obtained raw substrate, and carrying out hot-pressing sintering at the temperature of 80-390 ℃ and the pressure of 4-20 MPa for 120-240 min to obtain a microwave composite dielectric substrate;

ninthly, carrying out heat treatment on the obtained microwave composite dielectric substrate at the temperature of 80-250 ℃ and under the pressure of 2-10 MPa for 60-240 min to obtain a microwave composite dielectric substrate product with high thermal stability and high dimensional stability;

wherein, the coupling agent is selected from one or more of silane coupling agent, titanate coupling agent and zirconate coupling agent, and at least comprises silane coupling agent, and the dosage is 0.1-5.0 wt% of the total mass of the inorganic filler powder and the quartz fiber formula; the surfactant is one or more selected from polyethylene glycol laurate, polyhydroxy laurate and polyhydroxy propyl laurate, and the dosage of the surfactant is 0.1-1.5wt% of the mass of the quartz fiber formula.

The invention has the beneficial effects that:

the microwave composite dielectric substrate with high thermal stability and high dimensional stability, which is manufactured by the invention, has the relative dielectric constant of 2.5-4.5 and the dielectric loss of less than 1.0 multiplied by 10^-3The temperature coefficient of the relative dielectric constant is between-15 ppm/DEG C and 15 ppm/DEG C, the thermal expansion coefficient is less than 24 ppm/DEG C, the dimensional stability is less than 0.3mm/m, the requirements of low dielectric loss, uniform relative dielectric constant, low temperature coefficient of the relative dielectric constant, smaller thermal expansion coefficient and good dimensional stability are met, the preparation process is simple, the environment is friendly, the raw material source is convenient, and the industrial production is favorably realized.

The chopped quartz fibers are added in the preparation process of the microwave composite dielectric substrate, so that the mechanical property of the substrate material can be effectively improved, and meanwhile, an isostatic pressing process is adopted, so that the compactness and uniformity of the material are improved, the internal stress is reduced, the defects are effectively reduced, the substrate material has good comprehensive performance, low dielectric constant thermal change rate in high-temperature use, thermal expansion coefficient matched with copper foil, good heated dimensional stability and consistent dielectric constant are realized, the microwave composite dielectric substrate obtained by the invention has stable electrical and mechanical properties, and the microwave composite dielectric substrate has high reliability and obvious advantages in the aspects of plate processing and application.

The invention can be widely applied to high-tech fields such as communication, radar, satellite, high-speed rail, airplane, high-tip weaponry and the like, and has wide application prospect.

Detailed Description

A high thermal stability, high stable microwave composite medium base plate of size which characterized in that: the weight percentage ratio of the raw materials is 40-80 wt% of inorganic filler powder, 1-10 wt% of quartz fiber and 10-55wt% of fluorine-containing resin polymer system.

The inorganic filler is selected from one or more of silicon dioxide powder, aluminum oxide powder, zinc oxide powder, magnesium oxide powder, calcium sulfate powder and boron nitride powder, and at least comprises silicon dioxide powder, and the particle size D50 of the powder is 10-20 mu m.

The fluorine-containing resin polymer system is selected from one or more of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer and ethylene-chlorotrifluoroethylene copolymer, and at least comprises polytetrafluoroethylene.