Modified epoxidized polybutadiene-containing build-up film for FC-BGA packaging substrate, preparation method therefor and use thereof

Abstract

Disclosed in the present invention are a modified epoxidized polybutadiene-containing build-up film for an FC-BGA packaging substrate, a preparation method therefor and a use thereof. The build-up film is prepared from the following components in parts by weight: 45-100 parts of epoxy resin, 40-100 parts of an inorganic filler, 25-45 parts of a cyanate ester, 35-55 parts of bismaleimide, 5-10 parts of graphite, and 10-20 parts of modified epoxidized polybutadiene. The modified epoxidized polybutadiene is prepared as follows: dissolving a carboxyl-terminated polybutadiene in a first organic solvent, then adding a formic acid solution and a hydrogen peroxide solution to react to obtain carboxyl-terminated epoxidized polybutadiene; and dissolving the carboxyl-terminated epoxidized polybutadiene in the first organic solvent, and then adding (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) to react to obtain the modified epoxidized polybutadiene. During combustion, phosphorus‑containing groups in the modified epoxidized polybutadiene generate phosphaphenanthrene groups in the gas phase, which can capture free radicals from a gas‑phase pyrolysis product to form a stable structure, thereby exerting a free radical quenching effect and improving the flame retardant efficiency of the build-up film.

Description

A modified epoxidized polybutadiene-containing laminate for FC-BGA encapsulation substrate, its preparation method and application Technical Field

[0001] This invention relates to the field of resin composite materials technology, and in particular to an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene, its preparation method, and its application. Background Technology

[0002] Flip-chip ball grid array (FC-BGA) is an integrated circuit packaging technology. This packaging method involves inverting the chip and attaching it to a packaging substrate, then using ball solder joints to secure the package to the carrier. It is primarily used in high-density, high-speed, and multifunctional large-scale integrated circuit chip packaging applications, offering advantages such as high integration, small size, high performance, and low power consumption. The FC-BGA carrier is a high-density packaging carrier capable of enabling high-speed and multifunctional chips, and the additive bonding film is one of the key materials in the SAP semi-additive manufacturing process of the FC-BGA carrier.

[0003] Existing laminated film materials exhibit thermal stress due to the thermal expansion of the resin system. Excessive thermal stress can damage the reliability of the FC-BGA packaging substrate and its packaging system. Furthermore, the poor flame retardant properties of laminated films lead to a decrease in their application reliability.

[0004] Therefore, how to reduce the coefficient of thermal expansion of the laminated film, ensure the reliability of the laminated film product, guarantee good flame retardant properties, and improve the reliability of the laminated film product in practical applications has become an urgent technical problem to be solved. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention provides an additive film for FC-BGA packaging substrate containing modified epoxidized polybutadiene, its preparation method and application, thereby solving the problem of poor flame retardant effect of existing additive films.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] In a first aspect, the present invention provides an additive film for FC-BGA encapsulation substrate containing modified epoxidized polybutadiene, the additive film being prepared from the following components in parts by weight: 45-100 parts epoxy resin, 40-100 parts inorganic filler, 25-45 parts cyanate ester, 35-55 parts bismaleimide, 5-10 parts graphite and 10-20 parts modified epoxidized polybutadiene;

[0008] The method for preparing the modified epoxidized polybutadiene includes the following steps:

[0009] Carboxyl-terminated polybutadiene is dissolved in a first organic solvent, and then formic acid solution and hydrogen peroxide solution are added to carry out the reaction to obtain carboxyl-terminated epoxidized polybutadiene.

[0010] The carboxyl-terminated epoxidized polybutadiene was dissolved in a first organic solvent, and then (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) was added to carry out the reaction to obtain modified epoxidized polybutadiene.

[0011] Preferably, the graphite is aminated graphite.

[0012] Preferably, the preparation method of the aminated graphite is as follows:

[0013] Graphite is dispersed in a mixed acid solution of concentrated sulfuric acid and nitric acid and reacted to obtain acidified graphite.

[0014] The acidified graphite was dissolved in a second organic solvent, and then dicyclohexylcarbodiimide, 4-dimethylaminopyridine and acrylic acid were added. The reaction was carried out under inert gas protection to obtain carboxylated graphite.

[0015] The carboxylated graphite is dissolved in a second organic solvent, and then polyethylene polyamine is added. The reaction is carried out under the protection of an inert gas to obtain the amino graphite.

[0016] Preferably, the bismaleimide is a silicon-containing bismaleimide;

[0017] The silicon-containing bismaleimide is selected from any one or a combination of at least two of silicon-containing bismaleimide I, silicon-containing bismaleimide II, and silicon-containing bismaleimide III;

[0018] The structural formula of the silicon-containing bismaleimide I is as follows:

[0019] The structural formula of the silicon-containing bismaleimide II is:

[0020] The structural formula of the silicon-containing bismaleimide III is:

[0021] Preferably, the cyanate is a boron-containing cyanate.

[0022] Preferably, the method for preparing the borosilicate cyanate is as follows:

[0023] Cyanide bromide is dissolved in a third organic solvent, and then triethylamine and 1,2-bis(4-hydroxyphenyl)-o-dicarboxylated closed dodecorane are added to react and the reaction is carried out to obtain the boron cyanide ester.

[0024] Preferably, the epoxy resin is selected from any one or a combination of at least two of the following: bisphenol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, linear phenolic type epoxy resin, dicyclopentadiene type epoxy resin, aralkyl type phenolic epoxy resin, aralkyl biphenyl type phenolic epoxy resin, or naphthol type phenolic epoxy resin.

[0025] The inorganic filler is selected from any one or a combination of at least two of the following: silicon dioxide, alumina, glass, cordierite, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, calcium zirconate, or zirconium phosphate.

[0026] Preferably, the laminated film further includes 0.2-0.5 parts of a curing accelerator;

[0027] The curing accelerator is selected from any one or a combination of at least two of 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-ethyl-4-methylimidazole, and 4-dimethylaminopyridine.

[0028] A second aspect of the present invention provides a method for preparing an additive film for an FC-BGA encapsulation substrate containing modified epoxidized polybutadiene, the method comprising the following steps:

[0029] After the components of the laminate film are mixed evenly, they are coated onto the substrate and dried to obtain the laminate film.

[0030] A third aspect of the present invention provides the application of the above-described modified epoxidized polybutadiene-containing FC-BGA encapsulation substrate adhesive film in an FC-BGA encapsulation substrate. Beneficial effects:

[0031] This invention discloses an additive film for FC-BGA packaging substrates containing modified epoxidized polybutadiene, its preparation method, and its application. The invention modifies the epoxidized polybutadiene to contain phosphorus groups. During combustion, the phosphorus groups generate phosphorus-phenanthrene groups in the gas phase, which can capture free radicals from gas phase pyrolysis, form a stable structure, exert a free radical quenching effect, and improve the flame retardant efficiency of the additive film. Detailed Implementation

[0032] This invention provides a modified epoxidized polybutadiene-containing laminated adhesive film for FC-BGA encapsulation substrates, its preparation method, and its application. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0033] This invention provides an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene. The additive film is prepared from the following components in parts by weight: 45-100 parts epoxy resin, 40-100 parts inorganic filler, 25-45 parts cyanate ester, 35-55 parts bismaleimide, 5-10 parts graphite, and 10-20 parts modified epoxidized polybutadiene.

[0034] The method for preparing the modified epoxidized polybutadiene includes the following steps:

[0035] Carboxyl-terminated polybutadiene is dissolved in a first organic solvent, and then formic acid solution and hydrogen peroxide solution are added to carry out the reaction to obtain carboxyl-terminated epoxidized polybutadiene.

[0036] The carboxyl-terminated epoxidized polybutadiene was dissolved in a first organic solvent, and then (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) was added to carry out the reaction to obtain modified epoxidized polybutadiene.

[0037] This invention modifies epoxidized polybutadiene, which contains phosphorus groups. During combustion, these phosphorus groups generate phosphorus-phenanthrene groups in the gas phase, which can capture free radicals from gas phase pyrolysis, forming a stable structure and exerting a free radical quenching effect, thereby improving the flame retardant efficiency of the laminated film.

[0038] In some embodiments, the first organic solvent is selected from one or more of toluene, xylene, dichloromethane, and trichloromethane.

[0039] In some embodiments, the method for preparing the modified epoxidized polybutadiene includes the following steps:

[0040] Ten parts of carboxyl-terminated polybutadiene were dissolved in 300 parts of toluene and stirred at 90°C for 0.5 h. After complete dissolution, the mixture was cooled to 40°C, and then 3 parts of 80% formic acid solution and 6 parts of 30% hydrogen peroxide solution were added. The mixture was stirred at 30°C for 12 h to obtain a reaction solution. Deionized water was added to separate the formic acid and hydrogen peroxide from the reaction solution. This process was repeated several times until the pH of the reaction solution reached 6.8. Then, 500 parts of anhydrous ethanol were added to the reaction solution, and the precipitated product was dried to obtain carboxyl-terminated epoxidized polybutadiene.

[0041] 20 parts of carboxyl-terminated epoxidized polybutadiene were dissolved in 200 parts of toluene and stirred at 90°C for 0.5 h. After complete dissolution, 15 parts of (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) were added and stirred at 120°C for 12 h. After the reaction was completed, the solid product and toluene were separated by rotary evaporator. The solid product was dried to obtain modified epoxidized polybutadiene.

[0042] In some embodiments, the epoxy resin may be present in parts by weight of 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 parts.

[0043] The inorganic filler can be in the following weight proportions: 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, and 100 parts.

[0044] The cyanate ester can be in the following weight proportions: 25 parts, 30 parts, 35 parts, 40 parts, or 45 parts.

[0045] The weight parts of the bismaleimide can be 35 parts, 40 parts, 45 parts, 50 parts, or 55 parts;

[0046] The graphite can be in the following weight proportions: 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts.

[0047] The modified epoxidized polybutadiene can be present in weight parts of 10, 12, 14, 16, 18, or 20.

[0048] In some embodiments, the graphite is aminated graphite.

[0049] The amino groups in aminated graphite can react with the carboxyl groups in modified epoxidized polybutadiene to form a graphite / resin interface region. This interface region has a strong ability to constrain dipole polarization, which can reduce the loss caused by dipole polarization and thus reduce the dielectric loss of the system. In addition, after the reaction between aminated graphite and modified epoxidized polybutadiene, the molecular chain packing density can be increased. The denser the packing, the smaller the free volume, and the space for movement of resin molecular chain segments is restricted, thereby obtaining a reduced coefficient of thermal expansion.

[0050] Specifically, in this embodiment of the invention, the carboxyl groups of modified epoxidized polybutadiene react with the amino groups of aminated graphite to construct an interpenetrating network structure, which restricts the movement of epoxy resin molecular chain segments, reduces the thermal expansion coefficient of the system, and the interpenetrating network structure has high symmetry. When the frequency increases or decreases, the interpenetrating network structure is not sensitive to polarization relaxation, and its dielectric constant and dielectric loss factor do not change significantly, thereby achieving low dielectric loss of the film.

[0051] In some embodiments, the preparation method of the aminated graphite is as follows:

[0052] Graphite is dispersed in a mixed acid solution of concentrated sulfuric acid and nitric acid and reacted to obtain acidified graphite.

[0053] The acidified graphite was dissolved in a second organic solvent, and then dicyclohexylcarbodiimide, 4-dimethylaminopyridine and acrylic acid were added. The reaction was carried out under inert gas protection to obtain carboxylated graphite.

[0054] The carboxylated graphite is dissolved in a second organic solvent, and then polyethylene polyamine is added. The reaction is carried out under the protection of an inert gas to obtain the amino graphite.

[0055] Graphite is dispersed in a mixed acid solution of concentrated sulfuric acid and nitric acid, where concentrated sulfuric acid acts as a dehydrating agent and concentrated nitric acid provides nitro groups, to obtain acidified graphite. Under the combined action of dicyclohexylcarbodiimide, 4-dimethylaminopyridine, and acrylic acid, the carboxyl groups of the acrylic acid molecules are introduced into the graphite, forming carboxylated graphite. Carboxylated graphite reacts with polyethylene polyamine through an amidation reaction to introduce amino groups into the graphite structure, thereby obtaining aminated graphite.

[0056] In some embodiments, the second organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran.

[0057] In some embodiments, the preparation method of the amination graphite is as follows: 5 parts of graphite are weighed and dispersed in a mixed acid solution of 20 parts of concentrated sulfuric acid and 30 parts of nitric acid, ultrasonically dispersed for 1 hour under a power of 800W, and then refluxed at 160°C for 1.5 hours. The product is washed several times with distilled water until neutral, filtered, and dried to obtain acidified graphite.

[0058] One part of acidified graphite was weighed and dispersed in 100 parts of N,N-dimethylformamide. The dispersion was ultrasonically dispersed for 0.5 h at a power of 600 W to obtain a suspension. Four parts of dicyclohexylcarbodiimide, 0.4 parts of 4-dimethylaminopyridine, and 10 parts of acrylic acid were added to the suspension. The mixture was reacted at 90 °C for 20 h under a nitrogen atmosphere. After washing, filtering, and drying, carboxylated graphite was obtained.

[0059] Five parts of carboxylated graphite were weighed and dispersed in 100 parts of N,N-dimethylformamide. The dispersion was ultrasonically carried out for 1 hour at a power of 500W. Then, 4 parts of polyethylene polyamine were added and reacted at room temperature in a nitrogen atmosphere for 0.5 hours. The mixture was washed, filtered, and dried to obtain amino graphite.

[0060] In some embodiments, the bismaleimide is a silicon-containing bismaleimide;

[0061] The silicon-containing bismaleimide is selected from any one or a combination of at least two of silicon-containing bismaleimide I, silicon-containing bismaleimide II, and silicon-containing bismaleimide III;

[0062] The structural formula of the silicon-containing bismaleimide I is as follows:

[0063] The structural formula of the silicon-containing bismaleimide II is:

[0064] The structural formula of the silicon-containing bismaleimide III is:

[0065] It should be noted that the embodiments of the present invention do not impose any special limitations on the source of silicon-containing bismaleimide. It can be obtained by purchasing commercially available materials or prepared by oneself. Furthermore, the embodiments of the present invention do not impose any special limitations on its preparation method. For example, the preparation methods described in “Tang H, Song N, Chen X, et al. Synthesis and properties of silicon-containing bismaleimide resins[J]. Journal of Applied Polymer Science, 2010, 109(1):190-199.” and “Wei-Jye, Shu, Ruey-Shi, et al. Studies of Silicon-Containing Bismaleimide Resins. Part I: Synthesis and Characteristics of ModelCompounds and Polyaspartimides[J]. Designed Monomers&Polymers, 2010.” can be referred to.

[0066] Specifically, silicon-containing bismaleimides I, II, and III contain large-volume functional groups such as benzene rings with large molar volumes. These large-volume functional groups can restrict the movement of polymer chain segments and reduce the degree of polarization, thereby effectively reducing the dielectric constant and dielectric loss of the laminated film. In addition, the silicon element in silicon-containing bismaleimides I, II, and III decomposes to generate an oxide carbon layer. The oxide carbon layer can prevent the escape of volatile substances generated by the combustion of the material, isolate oxygen from contact with the resin, and prevent melt dripping, thereby achieving the purpose of flame retardancy.

[0067] In some embodiments, the cyanate ester is a boron-containing cyanate ester.

[0068] When boron in boron cyanide is heated, the boric anhydride or boric acid produced will form a glassy melt that covers the surface of the laminate film, isolating oxygen and heat transmission, inhibiting the generation of dense smoke and molten droplets, and improving the flame retardant properties of the laminate film.

[0069] In addition, the phosphoric acid generated by the decomposition of the phosphorus-containing groups of the modified epoxidized polybutadiene of this invention removes water from the matrix material to form a phosphorus-containing carbon layer. The silicon element of the silicon-containing bismaleimide has a low surface energy and can easily migrate to the surface of the matrix material to form a silicon-containing protective layer, which improves the thermal stability of the phosphorus-containing carbon layer on the surface of the matrix material and inhibits the oxidation of the phosphorus-containing carbon layer under high temperature conditions. The boron element containing boron cyanide can form a porous carbon layer with a ceramic-like structure at high temperature, which is beneficial for heat insulation and preventing air diffusion into the interior of the material. Through the combined action of phosphorus, boron and silicon elements, synergistic flame retardancy is achieved.

[0070] In some embodiments, the borosilicate ester is prepared as follows:

[0071] Cyanide bromide is dissolved in a third organic solvent, and then triethylamine and 1,2-bis(4-hydroxyphenyl)-o-dicarboxylated closed dodecorane are added to react and the reaction is carried out to obtain the boron cyanide ester.

[0072] The hydroxyl group in 1,2-bis(4-hydroxyphenyl)-ortho-dicarboxyclosed dodecorane is a nucleophilic center. The hydroxyl oxygen atom can attack the carbon atom in cyanobromide to form an intermediate. The intermediate is then deprotonated by triethylamine to give boron cyanide.

[0073] In some embodiments, the third organic solvent is selected from one or more of butanone, acetone, and cyclohexanone.

[0074] In some embodiments, the boron cyanate is prepared by dissolving 10 parts of cyanogen bromide in 50 parts of butanone, stirring evenly at 0°C, then adding 20 parts of triethylamine and 10 parts of 1,2-di(4-hydroxyphenyl)-o-dicarboxyclosed dodecorane, reacting at 5°C for 2 hours, obtaining the product by filtration and vacuum distillation, recrystallizing the product with isopropanol, and drying under vacuum to obtain the boron cyanate.

[0075] In some embodiments, the epoxy resin is selected from any one or a combination of at least two of bisphenol epoxy resin, biphenyl epoxy resin, naphthalene epoxy resin, naphthol epoxy resin, linear phenolic epoxy resin, dicyclopentadiene epoxy resin, aralkyl phenolic epoxy resin, aralkyl biphenyl phenolic epoxy resin, or naphthol phenolic epoxy resin.

[0076] The inorganic filler is selected from any one or a combination of at least two of the following: silicon dioxide, alumina, glass, cordierite, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, calcium zirconate, or zirconium phosphate.

[0077] In some embodiments, the laminated film further includes 0.2-0.5 parts by weight of a curing accelerator;

[0078] The curing accelerator is selected from any one or a combination of at least two of 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-ethyl-4-methylimidazole, and 4-dimethylaminopyridine.

[0079] In some embodiments, the curing accelerator may be present in parts by weight of 0.1, 0.2, 0.3, 0.4, or 0.5.

[0080] In some embodiments, the laminated film further includes 200-300 parts by weight of a component organic solvent;

[0081] The organic solvent of the component is selected from any one or a combination of at least two of toluene, xylene, butanone, methyl ethyl ketone, cyclohexanone, ethyl acetate, or N,N-dimethylformamide.

[0082] In some embodiments, the weight parts of the component organic solvent may be 200 parts, 210 parts, 220 parts, 230 parts, 240 parts, 250 parts, 260 parts, 270 parts, 280 parts, 290 parts, or 300 parts.

[0083] In some embodiments, the thickness of the laminated film is 10-100 μm.

[0084] In some preferred embodiments, the thickness of the laminated film is 25-50 μm.

[0085] This invention provides a method for preparing the above-mentioned modified epoxidized polybutadiene-containing FC-BGA encapsulation substrate extension film, the preparation method comprising the following steps:

[0086] After the components of the laminate film are mixed evenly, they are coated onto the substrate and dried to obtain the laminate film.

[0087] The drying temperature is 80-130℃, and the drying time is 3-10 minutes.

[0088] The drying temperature can be 80℃, 85℃, 90℃, 95℃, 100℃, 105℃, 110℃, 115℃, 120℃, 125℃, or 130℃; the drying time can be 3min, 4min, 5min, 6min, 7min, 8min, 9min, or 10min.

[0089] In some embodiments, the drying process further includes a post-treatment step: the post-treatment method is to remove the substrate.

[0090] It should be noted that the embodiments of the present invention do not have special limitations on the selection of the substrate; commonly used substrates in the art can be used, including but not limited to: PET release film, polyethylene film, polypropylene film, or polyvinyl chloride film. Furthermore, to facilitate subsequent removal of the substrate, the polyethylene film, polypropylene film, or polyvinyl chloride film can be pre-treated with corona discharge before use.

[0091] In some embodiments, the present invention provides the application of the above-mentioned modified epoxidized polybutadiene-containing FC-BGA encapsulation substrate extension film in FC-BGA encapsulation substrates.

[0092] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are merely some embodiments of the present invention, not all embodiments, and are intended only to illustrate the present invention and not to limit it. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0093] The sources of some components in the embodiments and comparative examples of this invention are as follows:

[0094] Epoxy resin: Naphthalene-type epoxy resin ("HP-6000" manufactured by DIC Corporation of Japan);

[0095] Inorganic filler: Silica (Yarduma Corporation "SO-C2");

[0096] Cyanate ester: Commercially available cyanate ester (Lonza Japan Co., Ltd. "BA230S75");

[0097] Bismaleimide: Commercially available bismaleimide (manufactured by Daiwa Chemical Industries, Ltd., Japan, "BMI5100");

[0098] Graphite: Commercially available graphite, CAS No.: 7782-42-5;

[0099] Curing accelerator: 4-Dimethylaminopyridine (DMAP), CAS No.: 1122-58-3.

[0100] Preparation Example 1

[0101] The preparation of boron cyanate includes the following steps: 10 parts of cyanogen bromide are dissolved in 50 parts of butanone and stirred evenly at 0°C. Then, 20 parts of triethylamine and 10 parts of 1,2-di(4-hydroxyphenyl)-o-dicarboxyclosed dodecylborane are added and reacted at 5°C for 2 hours. The product is obtained by filtration and vacuum distillation. The product is recrystallized with isopropanol and dried under vacuum to obtain boron cyanate.

[0102] Note: The boron cyanide used in the following examples or comparative examples is the boron cyanide prepared in Preparation Example 1.

[0103] Preparation Example 2

[0104] The preparation of modified epoxidized polybutadiene includes the following steps: 10 parts of carboxyl-terminated polybutadiene are dissolved in 300 parts of toluene and stirred at 90°C for 0.5 h. After complete dissolution, the mixture is cooled to 40°C, and then 3 parts of 80% formic acid solution and 6 parts of 30% hydrogen peroxide solution are added. The mixture is stirred at 30°C for 12 h to obtain a reaction solution. Deionized water is added to separate the formic acid and hydrogen peroxide in the reaction solution. This process is repeated several times until the pH of the reaction solution is 6.8. Then, 500 parts of anhydrous ethanol are added to the reaction solution, and the precipitated product is dried to obtain carboxyl-terminated epoxidized polybutadiene.

[0105] 20 parts of carboxyl-terminated epoxidized polybutadiene were dissolved in 200 parts of toluene and stirred at 90°C for 0.5 h. After complete dissolution, 15 parts of (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) were added and stirred at 120°C for 12 h. After the reaction was completed, the solid product and toluene were separated by rotary evaporator. The solid product was dried to obtain modified epoxidized polybutadiene.

[0106] Note: The modified epoxidized polybutadiene used in the following examples or comparative examples is the modified epoxidized polybutadiene prepared in Preparation Example 2.

[0107] Preparation Example 3

[0108] The preparation of ammoniated graphite includes the following steps: 5 parts of graphite are weighed and dispersed in a mixed acid solution of 20 parts concentrated sulfuric acid and 30 parts nitric acid, ultrasonically dispersed for 1 hour under a power of 800W, and then refluxed at 160℃ for 1.5 hours. The product is washed several times with distilled water until neutral, filtered, and dried to obtain acidified graphite.

[0109] One part of acidified graphite was weighed and dispersed in 100 parts of N,N-dimethylformamide. The dispersion was ultrasonically dispersed for 0.5 h at a power of 600 W to obtain a suspension. Four parts of dicyclohexylcarbodiimide, 0.4 parts of 4-dimethylaminopyridine, and 10 parts of acrylic acid were added to the suspension. The mixture was reacted at 90 °C for 20 h under a nitrogen atmosphere. After washing, filtering, and drying, carboxylated graphite was obtained.

[0110] Five parts of carboxylated graphite were weighed and dispersed in 100 parts of N,N-dimethylformamide. The dispersion was ultrasonically carried out for 1 hour at a power of 500W. Then, 4 parts of polyethylene polyamine were added and reacted at room temperature in a nitrogen atmosphere for 0.5 hours. The mixture was washed, filtered, and dried to obtain amino graphite.

[0111] Note: The aminated graphite used in the following examples or comparative examples is the aminated graphite prepared in Preparation Example 3.

[0112] Example 1

[0113] This embodiment provides an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene. The raw materials of the additive film, by weight, include:

[0114] 100 parts of naphthalene-type epoxy resin (HP-6000), 100 parts of spherical silica (SO-C2), 45 parts of boron cyanide, 55 parts of silicon-containing bismaleimide II, 20 parts of modified epoxidized polybutadiene, 10 parts of aminated graphite, 0.5 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0115] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0116] Example 2

[0117] This embodiment provides an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene. The raw materials of the additive film, by weight, include:

[0118] 45 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SO-C2), 25 parts of boron cyanide, 35 parts of silicon-containing bismaleimide I, 10 parts of modified epoxidized polybutadiene, 5 parts of amino graphite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 200 parts of cyclohexanone.

[0119] The preparation method of the laminated adhesive film is as follows: after the raw material components are mixed evenly according to the above proportions, the mixture is coated on a PET release film, dried at 130°C for 3 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 10 μm.

[0120] Example 3

[0121] This embodiment provides an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene. The raw materials of the additive film, by weight, include:

[0122] The composition includes 80 parts of naphthalene-type epoxy resin (HP-6000), 60 parts of spherical silica (SO-C2), 30 parts of boron cyanide ester, 40 parts of silicon-containing bismaleimide III, 15 parts of modified epoxidized polybutadiene, 8 parts of aminographite, 0.4 parts of 4-dimethylaminopyridine (DMAP), and 250 parts of cyclohexanone.

[0123] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 110°C for 5 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 40 μm.

[0124] Comparative Example 1

[0125] This comparative example provides an additive film, wherein the raw materials of the additive film, by weight, include:

[0126] 100 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SO-C2), 45 parts of cyanate ester (BA230S), 55 parts of bismaleimide (BMI5100), 10 parts of graphite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0127] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0128] Comparative Example 2

[0129] This comparative example provides an additive film, wherein the raw materials of the additive film, by weight, include:

[0130] 100 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SO-C2), 30 parts of boron cyanide, 55 parts of bismaleimide (BMI5100), 10 parts of graphite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0131] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0132] Comparative Example 3

[0133] This comparative example provides an additive film, wherein the raw materials of the additive film, by weight, include:

[0134] 100 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SO-C2), 45 parts of cyanate ester (BA230S), 55 parts of silicon-containing bismaleimide, 10 parts of graphite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0135] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0136] Comparative Example 4

[0137] This comparative example provides an additive film, wherein the raw materials of the additive film, by weight, include:

[0138] 100 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SO-C2), 45 parts of cyanate ester (BA230S), 55 parts of bismaleimide (BMI5100), 20 parts of modified epoxidized polybutadiene, 10 parts of graphite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0139] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0140] Comparative Example 5

[0141] This comparative example provides an additive film, wherein the raw materials of the additive film, by weight, include:

[0142] 100 parts of naphthalene-type epoxy resin (HP-6000), 40 parts of spherical silica (SOC2), 45 parts of cyanate ester (BA230S), 55 parts of bismaleimide (BMI5100), 10 parts of aminographite, 0.2 parts of 4-dimethylaminopyridine (DMAP), and 300 parts of cyclohexanone.

[0143] The preparation method of the laminated adhesive film is as follows: after mixing the raw material components evenly according to the above proportions, the mixture is coated onto a PET release film, dried at 80°C for 10 minutes, and then the PET release film is removed to obtain a laminated adhesive film with a thickness of 100 μm.

[0144] The performance of the laminated films provided in the above embodiments and comparative examples was tested using the following methods:

[0145] Coefficient of thermal expansion: The laminated adhesive films with PET release film prepared in the above examples and comparative examples were cured at 100°C for 30 min and at 190°C for 90 min. Then the release film was peeled off to obtain the test sample. The test sample was cut into test pieces with a width of about 3 mm and a length of about 20 mm. Thermomechanical analysis was performed using a thermomechanical analysis device (TA Instruments' "TMA450") under the conditions of a preload force of 0.02 N, a heating range of 25°C-260°C, and a heating rate of 10°C / min to obtain the coefficient of thermal expansion in the range of 150°C to 240°C.

[0146] Flame retardancy: The laminated adhesive films with PET release film prepared in the above examples and comparative examples were laminated to a substrate (MCL-E-705G from Hitachi Chemical, Japan) using a laminator. The laminated adhesive film (the side without PET release film) was laminated to both sides of the substrate to obtain a laminate. After lamination, the PET release film on the laminate was removed, and the laminated adhesive film was thermo-cured (cured at 190°C for 90 min) to form a cured product on both sides of the substrate. The laminate (thickness approximately 380 μm) was cut into samples of 12.7 mm × 127 mm with an edge of 1.27 mm, and tested according to the UL-94V standard. The test results were recorded.

[0147] Dielectric loss tangent: The extension films with PET release film prepared in the above examples and comparative examples were cured at 100°C for 30 min and at 190°C for 90 min. Then the release film was peeled off to obtain the pre-cured extension film. The pre-cured extension film was cut into 80 mm × 80 mm test pieces (3 pieces). Then, using Agilent Technologies' "HP8362B", the dielectric loss tangent of each test piece was measured using the cavity resonance perturbation method at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C. The average value of the 3 test pieces was then calculated as the dielectric loss tangent.

[0148] The performance test results of the laminated films provided in the examples and comparative examples are shown in Table 1:

[0149] Table 1

[0150] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene, characterized in that, The laminated film is prepared from the following components in parts by weight: 45-100 parts epoxy resin, 40-100 parts inorganic filler, 25-45 parts cyanate ester, 35-55 parts bismaleimide, 5-10 parts graphite and 10-20 parts modified epoxidized polybutadiene. The method for preparing the modified epoxidized polybutadiene includes the following steps: Carboxyl-terminated polybutadiene is dissolved in a first organic solvent, and then formic acid solution and hydrogen peroxide solution are added to carry out the reaction to obtain carboxyl-terminated epoxidized polybutadiene. The carboxyl-terminated epoxidized polybutadiene was dissolved in a first organic solvent, and then (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) was added to carry out the reaction to obtain modified epoxidized polybutadiene.

2. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 1, characterized in that, The graphite is an aminographite.

3. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 2, characterized in that, The preparation method of the aminated graphite is as follows: Graphite is dispersed in a mixed acid solution of concentrated sulfuric acid and nitric acid and reacted to obtain acidified graphite. The acidified graphite was dissolved in a second organic solvent, and then dicyclohexylcarbodiimide, 4-dimethylaminopyridine and acrylic acid were added. The reaction was carried out under inert gas protection to obtain carboxylated graphite. The carboxylated graphite is dissolved in a second organic solvent, and then polyethylene polyamine is added. The reaction is carried out under the protection of an inert gas to obtain the amino graphite.

4. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 1, characterized in that, The bismaleimide is a silicon-containing bismaleimide; The silicon-containing bismaleimide is selected from any one or a combination of at least two of silicon-containing bismaleimide I, silicon-containing bismaleimide II, and silicon-containing bismaleimide III; The structural formula of the silicon-containing bismaleimide I is as follows: The structural formula of the silicon-containing bismaleimide II is: The structural formula of the silicon-containing bismaleimide III is:

5. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 1, characterized in that, The cyanate ester is a boron-containing cyanate ester.

6. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 5, characterized in that, The method for preparing the borosilicate cyanate is as follows: Cyanide bromide is dissolved in a third organic solvent, and then triethylamine and 1,2-bis(4-hydroxyphenyl)-o-dicarboxylated closed dodecorane are added to react and the reaction is carried out to obtain the boron cyanide ester.

7. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 1, characterized in that, The epoxy resin is selected from any one or a combination of at least two of the following: bisphenol type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, linear phenolic type epoxy resin, dicyclopentadiene type epoxy resin, aralkyl type phenolic epoxy resin, aralkyl biphenyl type phenolic epoxy resin, or naphthol type phenolic epoxy resin. The inorganic filler is selected from any one or a combination of at least two of the following: silicon dioxide, alumina, glass, cordierite, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, calcium zirconate, or zirconium phosphate.

8. The reinforcing film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene according to claim 1, characterized in that, The laminated adhesive film also includes 0.2-0.5 parts of a curing accelerator; The curing accelerator is selected from any one or a combination of at least two of 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-ethyl-4-methylimidazole, and 4-dimethylaminopyridine.

9. A method for preparing an additive film for FC-BGA encapsulation substrates containing modified epoxidized polybutadiene as described in any one of claims 1-8, characterized in that, The preparation method includes the following steps: After the components of the laminate film are mixed evenly, they are coated onto the substrate and dried to obtain the laminate film.

10. The application of the modified epoxidized polybutadiene-containing FC-BGA encapsulation substrate as described in any one of claims 1-8 in the FC-BGA encapsulation substrate.

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