Epoxy plastic encapsulant, preparation method and application thereof

Abstract

The present application relates to the technical field of epoxy plastic packaging materials, and particularly relates to an epoxy plastic packaging material, a preparation method and application thereof. The epoxy plastic packaging material is made of a raw material composition containing an epoxy resin, a curing agent, a curing accelerator, an inorganic filler, a release agent, a coupling agent and an anionic wetting dispersant, wherein the anionic weting dispersant is a phosphate anionic wetting dispersant, and the curing accelerator is an imidazole curing accelerator. The epoxy plastic packaging material prepared by the present application has certain fluidity and adhesion, and has high die bending strength, so that the epoxy plastic packaging material can avoid problems such as broken ribs, edge collapse and mold contamination during the packaging process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of epoxy plastic packaging materials, in particular to an epoxy plastic packaging material and a preparation method and application thereof. BACKGROUND

[0002] With the continuous development of semiconductor devices, more and more countries have higher and higher requirements for semiconductor packaging materials, especially for some performance requirements, and more and more strict standards are put forward. However, in the packaging process of epoxy plastic packaging material, various problems are inevitable, such as the problem of broken ribs in the packaging process of epoxy plastic packaging material, which will affect the production efficiency, and the problems of edge collapse and mold contamination will directly affect the appearance of the plastic packaging material, thereby becoming a defective product. Once the produced plastic packaging material becomes a defective product, it cannot enter the market, and it will also pollute the environment. The problems of broken ribs, edge collapse and mold contamination in the packaging process are all related to the hot mold opening bending strength. The packaging material with good hot mold opening strength performance plays an important role in improving the manufacturing efficiency and reducing the packaging process defects, but the epoxy plastic packaging material for semiconductor packaging generally has the problem of low hot mold opening bending strength. SUMMARY

[0003] The purpose of the present application is to solve the problem of low hot mold opening bending strength of the epoxy plastic packaging material for semiconductor packaging in the prior art, and to provide an epoxy plastic packaging material and a preparation method and application thereof. In the preparation process of the epoxy plastic packaging material, raw materials containing phosphate anionic wetting dispersant and imidazole curing accelerator are used, so that the prepared epoxy plastic packaging material has high hot mold opening bending strength.

[0004] In the preparation of the raw material composition of the epoxy plastic packaging material, phosphate anionic wetting dispersant and imidazole curing accelerator are added. Under high temperature conditions, the imidazole group in the curing accelerator and the phosphate group in the phosphate anionic wetting dispersant undergo complexation reaction, which inhibits the crosslinking reaction degree of the imidazole curing accelerator to the epoxy resin and the phenolic resin. Under the same gelation time, this inhibition is conducive to the introduction of more curing accelerator into the system, thereby obtaining higher curing degree in the injection molding process, and finally obtaining high hot mold opening bending strength.

[0005] In order to achieve the above-mentioned purpose, the first aspect of the present application provides an epoxy plastic packaging material, which is made of a raw material composition containing epoxy resin, curing agent, curing accelerator, inorganic filler, release agent, coupling agent and anionic wetting dispersant, wherein the anionic wetting dispersant is phosphate anionic wetting dispersant, and the curing accelerator is imidazole curing accelerator.

[0006] Preferably, the content of the epoxy resin is 6 to 19% by weight, the content of the curing agent is 3 to 9% by weight, the content of the curing accelerator is 0.1 to 0.5% by weight, the content of the inorganic filler is 70 to 87% by weight, the content of the release agent is 0.2 to 1.0% by weight, the content of the coupling agent is 0.2 to 0.8% by weight, and the content of the anionic wet dispersant is 0.2 to 1.0% by weight, based on the content of the raw material composition as 100% by weight.

[0007] Preferably, the anionic wet dispersant is selected from one or more of dodecylphosphoric acid ester, hexadecylphosphoric acid ester, octadecylphosphoric acid ester, monododecylphosphoric acid ester triethanolamine, poly(oxo-1,2-ethylene)-Α-branched nonylphenyl-Ω-hydroxy-phosphoric acid ester, isomeric decanol polyoxyethylene ether phosphoric acid ester, and isomeric tridecanol polyoxyethylene ether phosphoric acid ester. More preferably, the anionic wet dispersant is selected from one or more of dodecylphosphoric acid ester, poly(oxo-1,2-ethylene)-Α-branched nonylphenyl-Ω-hydroxy-phosphoric acid ester, and isomeric decanol polyoxyethylene ether phosphoric acid ester.

[0008] Preferably, the curing accelerator is selected from one or more of 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-butylimidazole, 2-undecylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole. More preferably, the curing accelerator is selected from one or more of 2-phenyl-4-methylimidazole, 2-undecylimidazole, and 2-ethyl-4-methylimidazole.

[0009] Preferably, the epoxy resin is selected from one or more of o-cresol novolac epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, polyphenol type glycidyl ether epoxy resin, aliphatic glycidyl ether epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, and heterocyclic type epoxy resin.

[0010] Preferably, the curing agent is a phenol resin-based curing agent. More preferably, the curing agent is selected from one or more of phenol linear phenol resin and derivatives thereof, phenylcarbinol linear phenol resin and derivatives thereof, monohydroxy or dihydroxy naphthol novolac resin and derivatives thereof, condensate of p-xylene with phenol or naphthol, and copolymer of dicyclopentadiene with phenol.

[0011] Preferably, the inorganic filler is selected from one or more of alumina, titania, silicon nitride, aluminum nitride, and silica. More preferably, the inorganic filler is crystalline silica and / or fused silica.

[0012] Preferably, the release agent is selected from one or more than two of carnauba wax, synthetic wax and mineral wax.

[0013] Preferably, the coupling agent is selected from one or more than two of γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, methyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane.

[0014] Preferably, the raw material composition of the epoxy encapsulant further contains one or more than two of a flame retardant, a colorant and a modifier.

[0015] Preferably, the content of the flame retardant is 0-8 wt%, the content of the colorant is 0-1 wt%, and the content of the modifier is 0-1 wt%, based on 100 wt% of the raw material composition.

[0016] Preferably, the flame retardant is selected from one or more than two of a halogen-based flame retardant, a phosphorus-based flame retardant, a nitrogen-based flame retardant, a phosphorus-halogen-based flame retardant, a phosphorus-nitrogen-based flame retardant and a hydroxide-based flame retardant.

[0017] Preferably, the colorant is selected from one or more than two of titanium white, zinc oxide, zinc white and carbon black.

[0018] Preferably, the modifier is silicone oil and / or silicone rubber.

[0019] The second aspect of the present application provides a preparation method of the epoxy encapsulant as described above, which comprises the following steps:

[0020] (1) mixing the raw material composition of the epoxy encapsulant by stirring, and then melting and mixing the mixed material at a temperature of 70-100°C;

[0021] (2) cooling, crushing and preforming the melted and mixed material obtained in step (1) to obtain the epoxy encapsulant.

[0022] Preferably, in step (1), the temperature is 75-85°C.

[0023] The third aspect of the present application provides an application of the epoxy encapsulant as described above as a semiconductor packaging material.

[0024] By the above technical solution, the present application has at least the following beneficial effects:

[0025] (1) In the present application, by adding phosphate ester anionic wetting dispersant and imidazole curing accelerator in the raw material composition for preparing epoxy plastic encapsulant, under high temperature conditions, complexation reaction occurs between imidazole groups in the curing accelerator and phosphate groups in the phosphate ester anionic wetting dispersant, which inhibits the crosslinking reaction degree of imidazole curing accelerator on epoxy resin and phenolic resin, and in the case of the same gelation time, this inhibition is conducive to the introduction of more curing accelerator into the system, thereby obtaining higher curing degree in the injection molding process, and finally obtaining high hot open mold bending strength.

[0026] (2) In the present application, by adding phosphate ester anionic wetting dispersant and imidazole curing accelerator in the raw material composition for preparing epoxy plastic encapsulant, the prepared epoxy plastic encapsulant has certain fluidity and bonding properties, and has high open mold bending strength, so that the epoxy plastic encapsulant can avoid problems such as broken ribs, edge collapse, and mold contamination during packaging. DETAILED DESCRIPTION

[0027] The specific embodiments of the present application are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0028] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The endpoints of the ranges and the values are approximate values and should be understood to include values approximately near these ranges and values within these ranges. For ranges of values, the endpoints of the ranges are included in the ranges, and the endpoints and individual points within the ranges are combinable to form new ranges, which are also included in the ranges.

[0029] The first aspect of the present application provides an epoxy plastic encapsulant made of a raw material composition containing epoxy resin, curing agent, curing accelerator, inorganic filler, release agent, coupling agent and anionic wetting dispersant, wherein the anionic wetting dispersant is phosphate ester anionic wetting dispersant, and the curing accelerator is imidazole curing accelerator.

[0030] In the epoxy plastic encapsulant described in the present application, in order to improve the technical effects described in the present application, the amount of each component in the raw material composition needs to be limited within an appropriate range.

[0031] In the specific embodiment, the content of the epoxy resin is 6-19 wt%, the content of the curing agent is 3-9 wt%, the content of the curing accelerator is 0.1-0.5 wt%, the content of the inorganic filler is 70-87 wt%, the content of the release agent is 0.2-1.0 wt%, the content of the coupling agent is 0.2-0.8 wt%, and the content of the anionic wetting dispersant is 0.2-1.0 wt%, based on the content of the raw material composition being 100 wt%.

[0032] In the epoxy encapsulating material described in the present application, the complexation reaction between the imidazole group in the curing accelerator and the phosphate group in the phosphate anionic wetting dispersant occurs under high temperature conditions, which inhibits the crosslinking reaction degree of the imidazole curing accelerator to the epoxy resin and the phenolic resin, and this inhibition is conducive to the introduction of more curing accelerator into the system under the same gelation time, so as to obtain higher curing degree in the injection molding process, and finally obtain high hot open mold bending strength.

[0033] In the epoxy encapsulating material described in the present application, in the specific embodiment, the anionic wetting dispersant is selected from one or more of dodecyl phosphate, hexadecyl phosphate, octadecyl phosphate, monododecyl phosphate triethanolamine, poly(oxy-1,2-ethylene)-Α-branched nonyl phenyl-Ω-hydroxy-phosphate, isomeric decanol polyoxyethylene ether phosphate and isomeric tridecanol polyoxyethylene ether phosphate.

[0034] In the epoxy encapsulating material described in the present application, in the preferred embodiment, the anionic wetting dispersant is selected from one or more of dodecyl phosphate, poly(oxy-1,2-ethylene)-Α-branched nonyl phenyl-Ω-hydroxy-phosphate and isomeric decanol polyoxyethylene ether phosphate.

[0035] In the epoxy encapsulating material described in the present application, in the specific embodiment, the curing accelerator is selected from one or more of 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-butylimidazole, 2-undecylimidazole, 2-phenyl-4-methylimidazole and 2-heptadecylimidazole.

[0036] In the epoxy encapsulating material described in the present application, in the preferred embodiment, the curing accelerator is selected from one or more of 2-phenyl-4-methylimidazole, 2-undecylimidazole and 2-ethyl-4-methylimidazole.

[0037] In the epoxy molding compound of the present invention, in a specific embodiment, the epoxy resin is selected from one or more of the following: o-cresol epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, polyphenolic glycidyl ether epoxy resin, aliphatic glycidyl ether epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, and heterocyclic epoxy resin.

[0038] In the epoxy molding compound of the present invention, in a specific embodiment, the curing agent is a phenolic resin curing agent. In a preferred embodiment, the curing agent is selected from one or more of the following: linear phenolic resin and its derivatives, linear phenolic resin and its derivatives, monohydroxy or dihydroxynaphthol phenolic resin and its derivatives, condensates of p-xylene and phenol or naphthol, and copolymers of dicyclopentadiene and phenol.

[0039] In the epoxy molding compound of the present invention, in a specific embodiment, the inorganic filler is selected from one or more of alumina, titanium dioxide, silicon nitride, aluminum nitride, and silicon dioxide. In a preferred embodiment, the inorganic filler is crystalline silicon dioxide and / or molten silicon dioxide. In a more preferred embodiment, the inorganic filler is silane coupling agent modified silicon dioxide.

[0040] In the epoxy molding compound of the present invention, in a specific embodiment, the release agent is selected from one or more of carnauba wax, synthetic wax and mineral wax.

[0041] In the epoxy molding compound of the present invention, in a specific embodiment, the coupling agent is selected from one or more of γ-glycidyl ether trimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, methyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane.

[0042] In the epoxy molding compound of the present invention, in a specific embodiment, the raw material composition of the epoxy molding compound further contains one or more of flame retardants, colorants, and modifiers.

[0043] In the epoxy molding compound of the present invention, in a specific embodiment, based on the content of the raw material composition as 100% by weight, the content of flame retardant is 0-8% by weight, the content of colorant is 0-1% by weight, and the content of modifier is 0-1% by weight.

[0044] In the epoxy molding compound of the present invention, in a specific embodiment, the flame retardant is selected from one or more of halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, phosphorus-halogen-based flame retardants, phosphorus-nitrogen-based flame retardants, and hydroxide flame retardants.

[0045] In the epoxy molding compound of the present invention, in a specific embodiment, the colorant is selected from one or more of titanium dioxide, zinc oxide, zinc barium white and carbon black.

[0046] In the epoxy molding compound of the present invention, in a specific embodiment, the modifier is silicone oil and / or silicone rubber.

[0047] A second aspect of the present invention provides a method for preparing the epoxy molding compound described above, the method comprising the following steps:

[0048] (1) Stir and mix the raw material composition of epoxy molding compound, and then melt and knead the mixed material at a temperature of 70-100℃;

[0049] (2) Cool and crush the molten compound obtained in step (1) and preform it to obtain epoxy molding compound.

[0050] In the method of the present invention, in step (1), in a preferred embodiment, the temperature is 75-85°C, for example 75°C, 80°C or 85°C.

[0051] In the method of the present invention, in step (2), in a specific embodiment, the pulverized material can be pre-formed into a cake-shaped molding compound.

[0052] A third aspect of the present invention provides an application of the epoxy molding compound described above as a semiconductor packaging material.

[0053] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto.

[0054] In the following examples and comparative examples:

[0055] Epoxy resin: o-cresol epoxy resin (manufacturer: Baling Petrochemical, grade: CYDCN-200H);

[0056] Curing agent: Phenolic linear phenolic resin (manufacturer: Nippon Kayaku, grade: NC3000);

[0057] A1 Curing Accelerator: 2-Phenylon-4-methylimidazolium (Manufacturer: McLean, Brand: 2P4MZ);

[0058] A2 curing accelerator: 2-undecylimidazol (manufacturer: McLean, brand: C11ZA);

[0059] A3 curing accelerator: 2-ethyl-4-methylimidazolium (manufacturer: McLean, brand: 2E4MZ);

[0060] Inorganic filler: silica micro powder;

[0061] B1 Anionic Wetting and Dispersing Agent: Dodecyl Phosphate (Manufacturer: Huijun Chemical, Grade: C14);

[0062] B2 Anionic Wetting and Dispersing Agent: Poly(oxo-1,2-ethylidene)-A-branched nonylphenyl-Ω-hydroxy-phosphate ester (manufacturer: Solvay, brand name: RE-610);

[0063] B3 Anionic Wetting and Dispersing Agent: Isomeric decayl alcohol polyoxyethylene ether phosphate (manufacturer: Haian Petrochemical, brand: MOA-9P);

[0064] Release agent: Carnauba wax;

[0065] Coupling agent: γ-glycidyl oxypropyltrimethoxysilane (manufacturer: McLean, brand: KH560);

[0066] Flame retardant: Zinc borate;

[0067] Modifier: Liquid silicone oil (manufacturer: Dow Corning, grade: 8421);

[0068] Colorant: Carbon black.

[0069] The raw material components of Examples 1-9 and Comparative Examples 1-11 were proportioned according to Tables 1 and 2, respectively, and were carried out according to the following methods:

[0070] (1) Weigh each raw material component, then stir and mix each raw material composition, and melt and mix the mixed material evenly on an open rubber mixing mill at a temperature of 80°C.

[0071] (2) Cool and crush the molten compound obtained in step (1) and preform it into cake to obtain epoxy molding compound.

[0072] Table 1 Raw material ratios for Examples 1-9

[0073]

[0074]

[0075] Table 2 Raw material ratios for Comparative Examples 1-9

[0076]

[0077] Comparative Example 10

[0078] The method and proportions of the raw materials in Example 1 were followed, except that all the phosphate ester anionic wetting and dispersing agents in Example 1 were replaced with sodium dodecyl sulfate, a sulfate ester anionic wetting and dispersing agent.

[0079] Comparative Example 11

[0080] The process was carried out according to the raw material ratio and method of Example 1, except that all the imidazole curing accelerators in Example 1 were replaced with phosphine accelerators triethylphosphine boron trifluoride.

[0081] Test case

[0082] (1) Gelation time: Hot plate method. Heat the hot plate to 175±1℃, take 0.3-0.5g of the molding material sample powder and place it on the hot plate. The end point is when the powder gradually changes from fluid to gel. Read the gelation time.

[0083] (2) Spiral Flow Length: 20±5g of powdered molding material was taken for testing. The obtained powdered resin product was fed into an injection molding machine. Under the conditions of injection pressure of 60 bar and injection time of 15 s, the material was injected into a specially designed spiral test mold at 175℃. After curing for 120 s, the resin product was cured and removed, and the spiral flow length was read. The larger the spiral flow length, the better the material's fluidity.

[0084] (3) Copper Surface Adhesion Test: 20±5g of powdered molding material sample was taken for testing. The obtained powdered resin product was put into an injection molding machine, and the material was injected into a special adhesion test mold at 175℃ under the conditions of injection pressure of 60 bar and injection time of 15s. A shear force was applied along the sample surface at a speed of 20mm / min, and the maximum force value before the molding compound separated from the sample was tested. Five samples were tested for each example (or comparative example) of adhesion test, and the average value of the five test results was taken as the adhesion test result of that example (or comparative example). The greater the copper surface adhesion, the better the anti-delamination performance of the epoxy molding compound.

[0085] (4) Opening flexural strength and opening flexural modulus: 110g of powdered epoxy resin composition was added to an injection molding machine. Under the conditions of injection pressure of 60 bar and injection time of 15s, the material was injected into a specially made flexural strength test mold at 175℃ to form a sample block with specifications of 15.41*10.78*120mm. After curing for 120s, the resin product was cured and formed. Within 15s, the thermosetting sample was quickly taken out and placed in the test area of ​​a universal testing machine, and the pressure test was started. The opening flexural strength and opening flexural modulus tests were performed on 5 samples for each example (or comparative example). The average value of the 5 test results was taken as the opening flexural strength and opening flexural modulus test results of that example (or comparative example).

[0086] The gelation time, spiral flow length, copper surface adhesion, mold opening flexural strength, and mold opening flexural modulus of the epoxy molding compounds prepared in Examples 1-9 and Comparative Examples 1-11 were tested, and the results are shown in Table 3.

[0087] Table 3

[0088]

[0089]

[0090] The test results of Examples 1-9 and Comparative Examples 1-9 show that, under the same curing time, the epoxy molding compounds prepared in Examples 1-9 have an opening flexural strength in the range of 44.16-56.24 MPa and an opening flexural modulus in the range of 0.86-1.10 GPa, while the epoxy molding compounds prepared in Comparative Examples 1-9 have an opening flexural strength in the range of 30.51-35.46 MPa and an opening flexural modulus in the range of 0.71-0.80 GPa. Opening flexural strength and opening flexural modulus affect the encapsulation performance of epoxy molding compounds. Higher opening flexural strength and lower opening flexural modulus result in less likelihood of problems such as lead breakage, edge chipping, and mold contamination during the encapsulation process. However, an increase in opening flexural strength is often accompanied by an increase in opening flexural modulus. The increase in opening flexural strength in Examples 1-9 compared to Comparative Examples 1-9 does not significantly affect the opening flexural modulus; therefore, opening flexural strength is the primary improvement factor. Therefore, it can be seen that the epoxy molding compounds prepared in Examples 1-9 are less prone to problems such as broken threads, chipped edges, and contaminated molds during encapsulation compared to the epoxy molding compounds prepared in Comparative Examples 1-9, and the electronic devices prepared with them have better performance.

[0091] Although Comparative Examples 10 and 11 have mold opening bending strength and mold opening bending modulus that are close to the data of the Example, the gelation time and spiral flow length are too short, which easily leads to problems of incomplete sealing and missing sealing. At the same time, the short spiral flow length will result in insufficient wetting of the molding compound and the copper surface, leading to low copper adhesion. The produced molding compound is very prone to delamination.

[0092] The above are merely embodiments of the present invention and do not limit the scope of the patent. Any equivalent modifications made based on the content of this specification, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. An epoxy encapsulant, characterized by, The epoxy plastic encapsulating material is made of a raw material composition containing o-cresol novolac epoxy resin, phenol linear phenol resin, 2-undecylimidazole, silica powder, carnauba wax, gamma-glycidoxypropyltrimethoxysilane, isomeric decanol polyoxyethylene ether phosphate, zinc borate, liquid silicone oil and carbon black, wherein, based on the content of the raw material composition as 100% by weight, the content of o-cresol novolac epoxy resin is 13.31% by weight, the content of phenol linear phenol resin is 6.03% by weight, the content of 2-undecylimidazole is 0.5% by weight, the content of silica powder is 70.95% by weight, the content of carnauba wax is 0.48% by weight, the content of gamma-glycidoxypropyltrimethoxysilane is 0.62% by weight, the content of isomeric decanol polyoxyethylene ether phosphate is 1.0% by weight, the content of zinc borate is 5.88% by weight, the content of liquid silicone oil is 0.68% by weight, and the content of carbon black is 0.55% by weight.

2. A process for preparing the epoxy encapsulating material of claim 1, characterized by, The method comprises the following steps: (1) stirring and mixing the raw material composition of the epoxy plastic encapsulating material, and then melting and mixing the mixed material at a temperature of 70-100℃; (2) cooling, crushing and preforming the melting and mixing material obtained in step (1) to obtain the epoxy plastic encapsulating material.

3. The method of claim 2, wherein, In step (1), the temperature is 75-85℃.

4. Use of the epoxy plastic encapsulating material of claim 1 and the epoxy plastic encapsulating material prepared by the method of claim 2 or 3 as a semiconductor packaging material.

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