Resin composition, resin adhesive film and application thereof

Abstract

Provided are a resin composition, a resin adhesive film and an application thereof. The resin composition comprises the following components in parts by weight: 100 parts of epoxy resin, 10-60 parts of acrylic acid resin, 5-40 parts of phenoxy resin, 10-40 parts of polyester polyol resin, 40-160 parts of a curing agent, 300-1000 parts of an inorganic filler. The resin composition provided has a low elastic modulus, a low thermal expansion coefficient, low warpage, and good wafer filling properties. The resin adhesive film prepared does not blister during sealing, baking and curing, and is particularly suitable for large-size wafer-level advanced packaging.

Description

A resin composition, a resin film and its application Technical Field

[0001] This invention relates to the field of wafer-level packaging technology, and more particularly to a resin composition, a resin film, and their applications. Background Technology

[0002] Wafer-level packaging (WLP) is a type of chip packaging method that involves packaging and testing directly on the wafer after the entire wafer has been manufactured. Only after this process is completed is the wafer cut into individual chips. This eliminates the need for wire bonding or glue filling, greatly simplifying the wafer manufacturing process.

[0003] When commonly used wafer-level encapsulation films are applied to encapsulate wafer-level chips, reliability issues such as warping, breakage, and stress failure often arise. In particular, as wafer design dimensions increase and wafer thickness decreases, the possibility of wafer deformation under temperature changes and stress increases, which places very high demands on the thermal expansion coefficient of the encapsulation film.

[0004] The coefficient of thermal expansion of a wafer is approximately 2.6 ppm / ℃, while the coefficient of thermal expansion of existing encapsulating films is relatively high, making it difficult to fully meet the requirements of wafer-level packaging. Especially in large-size wafer-level packaging, the encapsulating film must also possess good fluidity during heat curing to completely fill the gaps between wafers, and remove residual small-molecule volatile substances from the film during sealing and baking curing to avoid stress concentration and failure risks caused by air bubbles, thereby enhancing the stability and reliability of the packaging.

[0005] Therefore, it is necessary to provide a resin composition that improves the elastic modulus and coefficient of thermal expansion of the film to solve the problems of encapsulation warping and sealing bubbling during baking. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a resin composition, a resin film, and their applications. The resin composition provided by this invention has a low elastic modulus, a low coefficient of thermal expansion, low warpage, and good wafer filling properties. The prepared resin film does not bubble during sealing, baking, and curing, making it particularly suitable for wafer-level advanced packaging.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a resin composition comprising the following components in parts by weight:

[0009] The mixture comprises 100 parts epoxy resin, 10-60 parts acrylic resin, 5-40 parts phenoxy resin, 10-40 parts polyester polyol resin, 40-160 parts curing agent, and 300-1000 parts inorganic filler.

[0010] In this invention, the acrylic resin can be, for example, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, or 55 parts; the phenoxy resin can be, for example, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, or 40 parts; the polyester polyol resin can be, for example, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, or 40 parts; the curing agent can be, for example, The quantities can be 45, 50, 55, 60, 65, 70, 80, 900, 100, 110, 120, 130, 140, or 150 parts, etc.; the inorganic fillers can be, for example, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, or 1000 parts, etc.

[0011] The "parts" and "parts by weight" used in this invention are calculated in terms of solid content and do not include solvents, dispersants, etc.

[0012] This invention uses epoxy resin as the main component and incorporates acrylic resin, polyester polyol resin, and phenoxy resin in a compound formulation. The acrylic resin and polyester polyol resin have a synergistic effect, jointly imparting to the resin composition the technical effects of low elastic modulus, low coefficient of thermal expansion, and low warpage. The acrylic resin and phenoxy resin together give the resin composition good flowability, enabling the formation of good venting channels in the resin film. This prevents bubbling after the resin film is sealed, baked, and cured, enhancing the stability and reliability of the encapsulation. It is particularly suitable for wafer-level advanced packaging.

[0013] In this invention, if the amount of acrylic resin added is too high, the flowability of the resin composition deteriorates; if the amount added is too low, it is difficult to effectively reduce the elastic modulus and coefficient of thermal expansion of the resin composition. If the amount of polyester polyol resin added is too high, the flowability of the resin composition increases; if the amount added is too low, it is difficult to effectively reduce the elastic modulus and coefficient of thermal expansion of the resin composition. If the amount of phenoxy resin added is too high, the elastic modulus and coefficient of thermal expansion of the resin composition will increase; if the amount added is too low, it is difficult to disrupt the film-forming properties of the resin composition, which is not conducive to the formation of venting channels.

[0014] Preferably, the number average molecular weight of the polyester polyol resin is 600 to 10000, for example, it can be 600, 1000, 4000, 5000, 8000 or 10000.

[0015] In this invention, the number-average molecular weight and weight-average molecular weight of the resin can be determined by referring to GB / T 21863-2008 Gel permeation chromatography (GPC) and using tetrahydrofuran as the eluent.

[0016] Preferably, the viscosity of the polyester polyol resin at 75°C is 50–10000 mPa·s, for example, it can be 80 mPa·s, 100 mPa·s, 500 mPa·s, 1000 mPa·s, 2000 mPa·s, 3000 mPa·s, 4000 mPa·s, 5000 mPa·s, 6000 mPa·s, 7000 mPa·s, 8000 mPa·s, or 9000 mPa·s. Exemplarily, the viscosity can be measured using an E-type viscometer.

[0017] Preferably, the hydroxyl value of the polyester polyol resin is 10-250 mg KOH / g, for example, it can be 10 mg KOH / g, 50 mg KOH / g, 100 mg KOH / g, 150 mg KOH / g, 200 mg KOH / g or 250 mg KOH / g, etc.

[0018] In this invention, the hydroxyl value of the polyester polyol resin is within the above-mentioned range, which allows it to have good compatibility with the resin system before thermosetting, and phase separation from the resin system after curing, thereby helping to reduce the elastic modulus.

[0019] Preferably, the melt flow rate of the acrylic resin under conditions of 230°C and 3.8 kg load is 1 to 6 g / 10 min, for example, it can be 1.5 g / 10 min, 2 g / 10 min, 2.5 g / 10 min, 3 g / 10 min, 3.5 g / 10 min, 4 g / 10 min, 4.5 g / 10 min, 5 g / 10 min, etc.

[0020] In this invention, the melt flow rate of the acrylic resin was determined according to JIS K7210 under the conditions of 230°C, 3.8 kg load, and 10 minutes.

[0021] In this invention, the acrylic resin can be prepared in-house or commercially available materials can be selected, such as JFE-S1150M30 from Suzhou Jufeng New Materials Co., Ltd.

[0022] In this invention, if the melt flow rate of the acrylic resin is too low, the resin composition will lack fluidity, making it impossible for the resin film to completely fill the gaps between wafers and difficult to perform the function of venting. If the melt flow rate of the acrylic resin is too high, the edge area of ​​the resin film will easily curl and adhere to the wafer, which will not be conducive to the removal of air bubbles.

[0023] Preferably, the weight-average molecular weight of the acrylic resin is 30,000 to 100,000, for example, 30,000, 40,000, 60,000, 80,000, 100,000, etc. If the weight-average molecular weight of the acrylic resin is too high, the viscosity of the resin composition will be too high, affecting the uniformity of dispersion of inorganic fillers in the resin composition; if the weight-average molecular weight of the acrylic resin is too low, it will cause the film to be sticky, affecting storage and subsequent processing.

[0024] Preferably, the weight-average molecular weight of the phenoxy resin is 20,000 to 100,000, for example, 20,000, 40,000, 60,000, 80,000, 100,000, etc. If the weight-average molecular weight of the phenoxy resin is too high, the viscosity of the resin solution in the resin composition will be too high, affecting the uniformity of dispersion of inorganic fillers in the resin composition; if the weight-average molecular weight of the phenoxy resin is too low, it will cause the adhesive film to be sticky, affecting storage and subsequent processing.

[0025] Preferably, the epoxy resin includes any one or a combination of at least two of the following: xylenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, triphenol type epoxy resin, phosphorus-containing epoxy resin, isocyanate modified epoxy resin, phenolic epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, alicyclic epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, or aminophenol type epoxy resin.

[0026] Preferably, the curing agent includes any one or a combination of at least two of the following: phenolic curing agents, reactive ester curing agents, amine curing agents, acid anhydride curing agents, carboxylic acid curing agents, cyanate ester curing agents, maleimide curing agents, or benzoxazine curing agents.

[0027] Preferably, the inorganic filler includes any one or a combination of at least two of the following: silicon dioxide, glass powder, aluminum nitride, boron nitride, silicon carbide, aluminum hydroxide, titanium dioxide, strontium titanate, barium titanate, aluminum oxide, barium sulfate, talc, calcium silicate, calcium carbonate, or mica.

[0028] Preferably, the silicon dioxide includes any one or a combination of at least two of amorphous silicon dioxide, crystalline silicon dioxide, fused silicon dioxide, spherical silicon dioxide, or hollow silicon dioxide.

[0029] Preferably, the particle size of the silica is 0.1 to 10 μm, for example, it can be 0.1 μm, 0.4 μm, 0.8 μm, 1.2 μm, 1.5 μm, 2 μm, 4 μm, 6 μm, 8 μm, 10 μm, etc.

[0030] In this invention, the particle size can be obtained by measuring the particle size using an MS3000 Malvern laser particle size analyzer.

[0031] Preferably, the silica is obtained by surface treatment with a coupling agent.

[0032] Preferably, the coupling agent includes any one or a combination of at least two of epoxy-based coupling agents, aniline-based coupling agents, or vinyl-based coupling agents.

[0033] Preferably, the resin composition further includes 0.01-1 part of an accelerator, such as 0.02 part, 0.05 part, 0.08 part, 0.1 part, 0.2 part, 0.5 part or 0.8 part, etc.

[0034] Preferably, the accelerator comprises any one or a combination of at least two of organometallic salt compounds, imidazole compounds, piperidine compounds, or tertiary amines.

[0035] Preferably, the accelerator comprises any one or a combination of at least two of the following: 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, tri-n-butylamine, triphenylphosphine, boron trifluoride complex, octanoic acid metal salt, acetylacetone metal salt, naphthenic acid metal salt, salicylic acid metal salt, or stearic acid metal salt.

[0036] Preferably, the octanoic acid metal salt, acetylacetone metal salt, naphthenic acid metal salt, salicylic acid metal salt, and stearic acid metal salt are each independently selected from any one or a combination of at least two of zinc salts, copper salts, iron salts, tin salts, cobalt salts, or aluminum salts.

[0037] In a second aspect, the present invention provides a resin adhesive obtained by dissolving or dispersing the resin composition as described in the first aspect in an organic solvent.

[0038] Preferably, the organic solvent includes any one or a combination of at least two of methanol, ethanol, butanol, ethyl cellosolve, butyl cellosolve, ethylene glycol methyl ether, carbitol, butyl carbitol, acetone, butanone, methyl ethyl ketone, cyclohexanone, toluene, xylene, ethyl acetate, ethoxyethyl acetate, N,N-dimethylformamide, or N,N-dimethylacetamide.

[0039] Thirdly, the present invention provides a resin film comprising a substrate film and a resin layer disposed on the substrate film; the resin layer is formed of a resin composition as described in the first aspect.

[0040] Fourthly, the present invention provides the application of the resin film as described in the third aspect in printed circuit boards or chip packaging.

[0041] Compared with the prior art, the present invention has at least the following beneficial effects:

[0042] This invention uses epoxy resin as the main component and introduces acrylic resin, polyester polyol resin and phenoxy resin in combination. The resulting resin composition not only has a low elastic modulus, low coefficient of thermal expansion, and low warpage, but also good wafer filling properties. The prepared resin film does not bubble after sealing, baking and curing. The resin film prepared using the resin composition provided by this invention has an elastic modulus of 4-8 GPa, a CTE of 6.2-10.2 ppm / ℃, a warpage of 0.4-0.9 mm, and a minimum melt viscosity of 900-1300 Pa·s, which fully meets the needs of wafer-level advanced packaging. Detailed Implementation

[0043] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0044] The materials and grade information involved in the following embodiments and comparative examples are as follows:

[0045] Biphenyl-type epoxy resin: NC-3000H, Nippon Kayaku;

[0046] Naphthalene-type epoxy resin: HP4710, DIC Japan;

[0047] Acrylic resin 1: JFE-S1150M30, Suzhou Jufeng New Materials, melt flow rate of 3g / 10min at 230℃ and 3.8kg, weight average molecular weight of 60000;

[0048] Acrylic resin 2: self-made, prepared as follows:

[0049] A monomer mixture was prepared by adding 99 parts by weight of purified methyl methacrylate and 1 part by weight of methyl acrylate to an autoclave equipped with a stirrer and sampling tube. Then, 0.007 parts by weight of polymerization initiator (2,2'-azobis(2-methylpropionitrile (AIBN)) and 0.26 parts by weight of chain transfer agent (n-octylthiol)) were added to the monomer mixture to dissolve it and obtain a raw material solution. Oxygen was then removed from the manufacturing apparatus using nitrogen gas.

[0050] The feed liquid was discharged from the autoclave and fed into a continuous flow-through tank reactor controlled at 120°C, with an average residence time of 120 minutes, for bulk polymerization. The reaction liquid was separated from the reactor sampling tube and analyzed by gas chromatography; the polymerization conversion rate was 55% by mass.

[0051] The liquid discharged from the reactor was heated at 230°C for 1 minute using a heater and then fed into a biaxial extruder controlled at 250°C. In this biaxial extruder, volatile components, primarily composed of unreacted monomers, were separated and removed, and the resin component was extruded into a filament. This filament was then cut using a granulator to obtain granular acrylic resin 2, which was found to have a melt flow rate of 2 g / 10 min at 230°C and 3.8 kg, and a weight-average molecular weight of 50,000.

[0052] Phenoxy resin 1: YL6954BH30, Mitsubishi Chemical, weight average molecular weight is 35000;

[0053] Phenoxy resin 2: YP-50S, Dongdu Chemical, with a weight-average molecular weight of 40,000;

[0054] Polyester polyol resin 1: FPS-610, DIC Japan, hydroxyl value 37.4 mg KOH / g, number average molecular weight 3000, viscosity at 75℃ 9000 mPa·s;

[0055] Polyester polyol resin 2: FPS-600, DIC Japan, hydroxyl value 102.2 mg KOH / g, number average molecular weight 2000, viscosity at 75℃ 2000 mPa·s;

[0056] Reactive ester curing agent: HPC-8000-65T, DIC Japan;

[0057] Cyanate ester curing agent: CE01PS, Yangzhou Tianqi;

[0058] Phenolic curing agent: SN485, Nippon Steel Chemicals

[0059] Inorganic filler: silica, SC2500-SXJ, Admatechs, Japan.

[0060] Example 1

[0061] 100 parts by weight of biphenyl epoxy resin (NC3000H, Nippon Kayaku), 100 parts by weight of reactive ester resin (HPC-8000-65T, DIC), 30 parts by weight of acrylic resin (JFE-S1150M30, Suzhou Jufeng New Materials), 20 parts by weight of polyester polyol resin (FPS-610, DIC, Japan), 10 parts by weight of phenoxy resin (YL6954BH30, Mitsubishi Chemical), 900 parts by weight of silica (SC2500-SXJ, Admatechs, Japan) and 0.2 parts by weight of accelerator (DMAP, Guangrong Chemical) were added to methyl ethyl ketone solvent and stirred for 2 hours to form a resin solution with a solid content of 65%.

[0062] The above resin solution was coated onto a PET substrate film, dried, and then baked in a 100°C oven for 3 minutes to obtain a resin film with a resin layer thickness of 40μm.

[0063] Examples 2-3, Comparative Examples 1-3

[0064] A resin composition and a resin film comprising the resin composition are disclosed. The components and contents of the resin composition are shown in Table 1, wherein the amount of each component is expressed in "parts by weight" of solid content. The preparation method of the resin film is the same as that in Example 1.

[0065] The performance of the resin films from the above embodiments and comparative examples was tested. The test items and methods are as follows:

[0066] (1) Coefficient of thermal expansion (CTE)

[0067] After the resin film was cured at 200℃ for 60 minutes, it was tested using the IPC-TM-650 2.4.24.5 method.

[0068] (2) Elastic modulus

[0069] After the resin film was cured at 200℃ for 60 minutes, it was tested using IPC TM650 method 2.4.24.4.

[0070] (3) Warp evaluation

[0071] The resin film with PET substrate film was cut into 300×300mm samples and pressed onto a 35μm thick copper foil using a vacuum laminator. It was first cured at 100℃ for 30min, then cured at 190℃ for 90min. After cooling to room temperature, it was placed horizontally on a flat marble tabletop, and the maximum warping value was observed, in mm.

[0072] (4) Flowability (minimum melt viscosity value)

[0073] The rheological curve of the resin layer in the resin film was tested using an Anton Paar MCR302 rheometer. The test temperature range was set to 30-190℃, and the heating rate was 3℃ / min. After the test, the lowest melt viscosity value appearing between 60-160℃ was read from the corresponding rheological curve.

[0074] (5) Evaluation of bubbling properties

[0075] On an 8-inch wafer, a resin film with a PET substrate is pressed onto the wafer using a molding apparatus (mold temperature: 130℃, pressure: 6MPa, curing time: 10 minutes). The resin layer side of the resin film is bonded to the wafer. Then, after heating at 150℃ for 60 minutes, the PET substrate film is removed, and the surface of the wafer is visually observed for bubbles. Wafers without bubbles are marked as "excellent", and wafers with bubbles are marked as "poor".

[0076] The test results of the resin films in Examples 1-3 and Comparative Examples 1-3 are shown in Table 1:

[0077] Table 1

[0078] As shown in Table 1, the resin films prepared from the resin compositions provided in Examples 1-3 of this invention have low elastic modulus and low coefficient of thermal expansion, achieving low warpage and a low minimum melt viscosity. They can fully fill the gaps between wafers, and the prepared resin films do not bubble after sealing, baking, and curing, making them particularly suitable for large-size wafer-level advanced packaging. Specifically, the resin films have an elastic modulus of 4-8 GPa, a CTE of 6.2-10.2 ppm / ℃, a warpage of 0.4-0.9 mm, and a minimum melt viscosity of 900-1300 Pa·s.

[0079] Compared with Example 1, Comparative Example 1 did not use acrylic resin, and its elastic modulus, coefficient of thermal expansion, and warpage were significantly increased, and its bubbling performance was poor, failing to meet the requirements of wafer-level packaging; Comparative Example 2 did not use polyester polyol resin, and its elastic modulus, coefficient of thermal expansion, and warpage were also increased; Comparative Example 3 did not use phenoxy resin, and its minimum melt viscosity value was significantly increased, and its bubbling performance was poor, failing to meet the requirements of wafer-level packaging.

[0080] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A resin composition, characterized in that, The resin composition comprises the following components in parts by weight: The mixture comprises 100 parts epoxy resin, 10-60 parts acrylic resin, 5-40 parts phenoxy resin, 10-40 parts polyester polyol resin, 40-160 parts curing agent, and 300-1000 parts inorganic filler.

2. The resin composition according to claim 1, characterized in that, The number-average molecular weight of the polyester polyol resin is 600 to 10,000. Preferably, the viscosity of the polyester polyol resin at 75°C is 50–10000 mPa·s; Preferably, the hydroxyl value of the polyester polyol resin is 10-250 mg KOH / g.

3. The resin composition according to claim 1 or 2, characterized in that, The acrylic resin has a melt flow rate of 1–6 g / 10 min under conditions of 230°C and 3.8 kg load.

4. The resin composition according to any one of claims 1 to 3, characterized in that, The weight-average molecular weight of the acrylic resin is 30,000 to 100,000.

5. The resin composition according to any one of claims 1 to 4, characterized in that, The weight-average molecular weight of the phenoxy resin is 20,000 to 100,000.

6. The resin composition according to any one of claims 1 to 5, characterized in that, The epoxy resin includes any one or a combination of at least two of the following: xylenol type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, triphenol type epoxy resin, phosphorus-containing epoxy resin, isocyanate modified epoxy resin, phenolic epoxy resin, biphenyl type epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, alicyclic epoxy resin, glycidylamine type epoxy resin, glycidyl ester type epoxy resin, or aminophenol type epoxy resin. Preferably, the curing agent includes any one or a combination of at least two of the following: phenolic curing agents, reactive ester curing agents, amine curing agents, acid anhydride curing agents, carboxylic acid curing agents, cyanate ester curing agents, maleimide curing agents, or benzoxazine curing agents.

7. The resin composition according to any one of claims 1 to 6, characterized in that, The inorganic filler includes any one or a combination of at least two of the following: silicon dioxide, glass powder, aluminum nitride, boron nitride, silicon carbide, aluminum hydroxide, titanium dioxide, strontium titanate, barium titanate, aluminum oxide, barium sulfate, talc, calcium silicate, calcium carbonate, or mica. Preferably, the silica includes any one or a combination of at least two of amorphous silica, crystalline silica, fused silica, spherical silica, or hollow silica; Preferably, the silica has a particle size of 0.1–10 μm; Preferably, the silica is obtained by surface treatment with a coupling agent; Preferably, the coupling agent includes any one or a combination of at least two of epoxy-based coupling agents, aniline-based coupling agents, or vinyl-based coupling agents; Preferably, the resin composition further includes 0.01-1 part of an accelerator; Preferably, the accelerator comprises any one or a combination of at least two of organometallic salt compounds, imidazole compounds, piperidine compounds, or tertiary amines; Preferably, the accelerator comprises any one or a combination of at least two of the following: 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, tri-n-butylamine, triphenylphosphine, boron trifluoride complex, octanoic acid metal salt, acetylacetone metal salt, naphthenic acid metal salt, salicylic acid metal salt, or stearic acid metal salt. Preferably, the octanoic acid metal salt, acetylacetone metal salt, naphthenic acid metal salt, salicylic acid metal salt, and stearic acid metal salt are each independently selected from any one or a combination of at least two of zinc salts, copper salts, iron salts, tin salts, cobalt salts, or aluminum salts.

8. A resin adhesive, characterized in that, The resin solution is obtained by dissolving or dispersing the resin composition as described in any one of claims 1 to 7 in an organic solvent; Preferably, the organic solvent includes any one or a combination of at least two of methanol, ethanol, butanol, ethyl cellosolve, butyl cellosolve, ethylene glycol methyl ether, carbitol, butyl carbitol, acetone, butanone, methyl ethyl ketone, cyclohexanone, toluene, xylene, ethyl acetate, ethoxyethyl acetate, N,N-dimethylformamide, or N,N-dimethylacetamide.

9. A resin film, characterized in that, The resin film includes a substrate film and a resin layer disposed on the substrate film; the resin layer is formed from the resin composition as described in any one of claims 1 to 7.

10. The application of the resin film as described in claim 9 in printed circuit boards or chip packaging.

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