Epoxy resin composition and use thereof in wide-row sot23 packaging

Abstract

The present invention relates to the technical field of electronic packaging, and in particular relates to an epoxy resin composition and the use thereof in wide-row SOT23 packaging. The raw materials of the epoxy resin composition comprise: 3-20 parts of an epoxy resin base material, 2-12 parts of a cross-linking agent, 45-110 parts of a shaping agen, and 0.02-4 parts of a catalyst. The present invention significantly improves the fluidity of the epoxy molding material by adding a resin with a low viscosity and a high toughness. This improvement enables easier mold filling during encapsulation and reduces wire sweeping, which in turn improves the encapsulation quality and production efficiency, thereby improving the packaging quality and production efficiency, and is especially suitable for wide-row SOT23 (such as 27 rows) packaging. Moreover, the epoxy molding material designed in the present invention can pass the stringent test of Moisture Sensitivity Level 1 (MSL1) evaluation, ensuring the stability and reliability of the product in humid environments, and meeting the market requirement for high-performance, high-reliability electronic products.

Description

An epoxy resin composition and its application in wide-pack SOT23 packaging Technical Field

[0001] This invention relates to the field of electronic packaging technology, and more particularly to an epoxy resin composition and its application in wide-pack SOT23 packaging. Background Technology

[0002] In recent years, wide-row SOT23 packages (especially high-density arrangements like 27 rows) have gradually emerged in the semiconductor packaging and testing industry and are increasingly favored by packaging and testing plants. This packaging form is highly regarded primarily because it significantly improves production efficiency. The wide-row design allows for more pins to be accommodated within the same package area, simplifying the packaging process, shortening production cycles, and ultimately achieving a leap in production capacity. At the same time, wide-row SOT23 packages can effectively reduce packaging costs, which is crucial for enhancing product market competitiveness.

[0003] However, with the widespread application of wide-array SOT23 packaging technology, packaging and testing companies are placing increasingly stringent quality requirements on molded products. Among these requirements, Moisture Sensitivity Level (MSL) assessment has become a crucial factor. The MSL level reflects the packaging material's sensitivity to moisture, with MSL1 being the lowest level, but still requiring the molded product to withstand a certain degree of moisture exposure without performance degradation. This necessitates that epoxy molding materials not only possess excellent flowability to ensure sufficient filling of the mold and tight encapsulation of the chip during the packaging process, but also reliable anti-delamination capabilities to prevent internal delamination or cracking in humid environments.

[0004] To meet these stringent requirements, the research and development and production processes of epoxy molding compounds must be continuously upgraded. Chinese patent application CN114685938A discloses an epoxy resin composition for electronic packaging and its preparation method. It improves the mechanical properties of the product by using a suitable weight ratio of spherical alumina with a particle size range of 1-55 μm and spherical alumina with a particle size range of less than 1 μm, while adding a certain amount of boron nitride to increase the thermal conductivity and improve the product's thermal performance. However, its flexural modulus reaches over 20,000 MPa, resulting in limited flowability. Chinese patent application CN116855211A discloses a low-viscosity, low-dielectric-constant underfill adhesive, its preparation method, and its application. It uses an epoxy resin containing at least bisphenol F diglycidyl ether and a rationally combined alkoxyphenyl triepoxide monomer with three epoxy functional groups. In addition to low viscosity and good flowability, it also possesses a low dielectric constant and good heat resistance. However, the moisture resistance of this adhesive still needs improvement.

[0005] In summary, existing technologies have not simultaneously improved the flowability and moisture resistance of epoxy resin compositions. There is an urgent need to provide an epoxy resin composition that has good flowability, moisture resistance, and stable reliability to meet the application requirements of electronic packaging (especially wide-panel SOT23) components. Summary of the Invention

[0006] The widespread adoption of wide-row SOT23 packaging technology has placed higher demands on epoxy molding materials. This invention provides a high-flowability epoxy resin composition and its preparation method for application in wide-row SOT23 packaging. By adding low-viscosity, high-toughness resin to the epoxy resin composition, the flowability and anti-delamination ability of the packaging material are improved, thereby solving the problems of wire breakage and delamination in the molding process and meeting the requirements of wide-row SOT23 packaging.

[0007] The first aspect of the present invention provides an epoxy resin composition, wherein, by weight, the raw materials of the epoxy resin composition include: 3-20 parts of epoxy resin base, 2-12 parts of crosslinking agent, 45-110 parts of plasticizer and 0.02-4 parts of catalyst.

[0008] Preferably, the raw materials of the epoxy resin composition, by weight, include: 4-15 parts epoxy resin base, 1-6 parts crosslinking agent, 80-95 parts plasticizer and 0.1-1 parts catalyst.

[0009] In some preferred embodiments, the raw materials of the epoxy resin composition further include, by weight, 0-15 parts of additives, excluding endpoint values; more preferably, 0-3 parts.

[0010] The present invention allows for the selection of additives based on actual needs. Examples of additives include coupling agents, colorants, lubricants, toughening agents, stress modifiers, flame retardants, antistatic agents, and ultraviolet absorbers.

[0011] Preferably, the additives include one or more combinations of coupling agents, colorants, and lubricants.

[0012] More preferably, the additives include coupling agents, colorants and lubricants in a mass ratio of 1:(1.1-1.7):(1.1-1.7).

[0013] In some preferred embodiments, the epoxy resin composition satisfies one or more of the following conditions A to E:

[0014] A spiral flow length is 30-65 inches, and the test conditions are curing at 175°C for 90 seconds;

[0015] B gelation time is 20-45 seconds, and the test condition is 175℃;

[0016] C viscosity is 4-12 Pa·s, test conditions are 175℃;

[0017] The water absorption rate (PCT, 24h) is less than 1%;

[0018] The flexural modulus E is below 1200 MPa.

[0019] More preferably, the epoxy resin composition satisfies at least two of the following conditions A to E:

[0020] A spiral flow length is 35-60 inches, and the test conditions are curing at 175°C for 90 seconds;

[0021] B gelation time is 22-40 seconds, and the test condition is 175℃;

[0022] C viscosity is 5-10 Pa·s, test conditions are 175℃;

[0023] The water absorption rate (PCT, 24h) is 0.2-0.4%;

[0024] The flexural modulus E is 600-1000 MPa.

[0025] More preferably, the epoxy resin composition satisfies at least conditions C and E; more preferably, the epoxy resin composition satisfies conditions A to E simultaneously.

[0026] In some preferred embodiments, the epoxy resin base material has a structural formula that is a combination of one or more compounds as shown in Formula I and Formula II;

[0027] Formula I:

[0028] Formula II:

[0029] In Equation I, n is selected from 1 or 2.

[0030] More preferably, the epoxy resin base material includes at least a compound of formula II.

[0031] More preferably, the epoxy resin base material comprises a compound of Formula I and Formula II in a mass ratio of (1.5-3):1.

[0032] The compounds represented by Formula I and Formula II are all commercially available, including but not limited to the following sources.

[0033] Formula I: Supplier: Changchun Artificial Resin Factory, Product Model: CNE-195LL.

[0034] Formula II: Supplier: Mitsubishi Chemical Corporation, product model: jER YX4000.

[0035] In some preferred embodiments, the crosslinking agent comprises a phenolic resin, wherein the phenolic resin has a structural formula of one or more compounds as shown in Formula III and Formula IV;

[0036] Formula III:

[0037] Formula IV:

[0038] In Equations III and IV, n is independently selected from either 1 or 2.

[0039] More preferably, the crosslinking agent comprises a compound of formula III and formula IV in a mass ratio of (0.5-2):1; even more preferably, it is 1:1.

[0040] The compounds shown in Formula III and Formula IV are all commercially available, including but not limited to the following sources.

[0041] Formula III: Supplier: Shandong Shengquan New Material Co., Ltd., Product model: PF8011.

[0042] Formula IV: Supplier: Hunan Jiashengde Materials Technology Co., Ltd., Product Model: BPNH9781S.

[0043] In some preferred embodiments, the mass ratio of the epoxy resin base to the crosslinking agent is 1:(0.4-0.9).

[0044] In some preferred embodiments, the shaping agent includes at least one of silicon dioxide and aluminum oxide.

[0045] Preferably, the silicon dioxide includes one or more of angular silicon dioxide, spherical silicon dioxide, fibrous silicon dioxide, and thin-film silicon dioxide; more preferably, it is angular silicon dioxide or spherical silicon dioxide; and even more preferably, it is spherical silicon dioxide.

[0046] Preferably, the silica may further include crystalline silica, such as α-quartz, β-quartz, tridymite, cristobalite, etc.

[0047] To enhance the filling effect of the plasticizer in the epoxy resin composition, more preferably, the spherical silica has a particle size D50 value of 10-50 μm and a specific surface area of ​​1-10 m². 2 / g.

[0048] More preferably, the maximum particle size of the spherical silica is 60-100 μm, and more preferably 75 μm.

[0049] Most preferably, the spherical silica has a maximum particle size of 75 μm, a particle size D50 value of 20 μm, and a specific surface area of ​​2.5 m². 2 / g; the spherical silica can be commercially available, such as Jiangsu Lianrui New Materials Co., Ltd.

[0050] More preferably, the spherical silica has a particle size D50 value of 15-30 μm and a specific surface area of ​​2-5 m². 2 / g.

[0051] In some preferred embodiments, the mass ratio of the epoxy resin base to the plasticizer is (5-10):(80-92).

[0052] In some preferred embodiments, the catalyst comprises one or more of imidazole compounds, triphenylphosphine, and triphenylphosphine-benzoquinone adducts; more preferably, the catalyst comprises one or more of triphenylphosphine and triphenylphosphine-benzoquinone adducts; most preferably, the catalyst comprises a triphenylphosphine-benzoquinone adduct.

[0053] In some preferred embodiments, the catalyst is added to the epoxy resin composition in an amount of 0.1-0.5 wt%.

[0054] The coupling agents may include 3-(glycidyloxypropyl)trimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, vinyltrimethoxysilane, etc.

[0055] Preferably, the coupling agent comprises one or more combinations of 3-(glycidyloxypropyl)trimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane.

[0056] More preferably, the coupling agent comprises 3-(glycidyloxypropyl)trimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane in a mass ratio of 1:(0.5-1.5):(0.5-1.5).

[0057] In some preferred embodiments, the lubricant includes at least one of natural wax and synthetic wax; the natural wax may include carnauba wax, candelilla wax, wood wax, beeswax, paraffin wax and its derivatives, etc.; the synthetic wax may include polyethylene wax, polypropylene wax, polyester wax, polyurethane wax, etc.

[0058] To avoid friction and damage to the surface of the product from the mold, the lubricant is more preferably a natural wax, and more preferably carnauba wax. Choosing carnauba wax reduces fluid resistance and contributes to the uniformity and density of the internal structure of the product, thereby improving the product's intrinsic quality.

[0059] This invention does not impose any particular limitation on the colorant, such as carbon black.

[0060] A second aspect of the present invention provides a method for preparing an epoxy resin composition, wherein the preparation steps of the epoxy resin composition include:

[0061] Step 1: Crush the epoxy resin and crosslinking agent separately, package and seal them for later use;

[0062] Step 2: Mix all raw materials except epoxy resin and crosslinking agent, then add the pulverized epoxy resin and crosslinking agent, and mix.

[0063] Step 3 involves mixing and extruding the material obtained in Step 2, followed by cooling to obtain an epoxy resin composition product.

[0064] In some preferred embodiments, the epoxy resin composition is prepared under low-temperature, low-humidity production conditions.

[0065] In some preferred embodiments, the preparation steps of the epoxy resin composition include:

[0066] Step 1: Crush the epoxy resin and crosslinking agent separately, package and seal them, and store them at low temperature for later use;

[0067] Step 2: Add the plasticizer, catalyst, and additives to the high-speed mixer in batches and mix. Then add the pulverized epoxy resin and crosslinking agent and mix.

[0068] Step 3: Transfer the material obtained in Step 2 to an extruder for mixing and extrusion, cool and then crush to obtain the epoxy resin composition product.

[0069] Preferably, the product obtained in step three is stored in a sealed container at a low temperature; more preferably, the low temperature is below 5°C.

[0070] Preferably, in step one, a resin pulverizer is used for pulverization, and the operating temperature is below 25°C, more preferably 10-20°C, and most preferably 15°C.

[0071] Preferably, the operating temperature in step two is below 25°C, more preferably 10-20°C, and most preferably 15°C.

[0072] Preferably, the ambient humidity in steps one through three is below 50% RH; more preferably, it is 40% RH.

[0073] In some embodiments, the extruder includes a single-screw extruder or a twin-screw extruder; preferably, the extruder is a twin-screw extruder.

[0074] Preferably, the extrusion temperature is 95-115°C, more preferably 100°C.

[0075] A third aspect of the present invention provides an application of an epoxy resin composition, which is used in the field of electronic packaging, and is particularly suitable for wide-panel SOT23 packaging.

[0076] SOT (Small Outline Transistor) is a surface-mount package typically used for small outline transistors with 5 or fewer pins. Wide-line SOT23 refers to a wider pin arrangement within the SOT23 package to accommodate components with more pins or larger dimensions. SOT23 is a small surface-mount package with a relatively small size, suitable for applications requiring space saving. The size standard for this package is standardized across the industry to ensure interchangeability between components from different manufacturers. Wide-line SOT23 packages are widely used in various electronic devices due to their small size, high pin count, and excellent performance. For example, wide-line SOT23 packaged components play a crucial role in consumer electronics such as smartphones, tablets, and digital cameras. Furthermore, wide-line SOT23 packages are also widely used in automotive electronics and industrial control.

[0077] With the widespread application of wide-panel SOT23 packaging technology, packaging and testing companies are increasingly stringent in their quality requirements for molded products. Among these requirements, Moisture Sensitivity Level (MSL) assessment has become a crucial factor. The MSL level reflects the packaging material's sensitivity to moisture, and wide-panel SOT23 packaging, due to its large number of pins and complex structure, places higher demands on the flowability and anti-delamination capabilities of epoxy molding materials. In this context, epoxy molding materials need to possess good flowability to ensure sufficient filling of the mold and tight encapsulation of the chip during the packaging process, avoiding voids or air bubbles. Simultaneously, epoxy molding materials also need to possess anti-delamination capabilities to prevent internal delamination or cracking in humid environments, thereby ensuring the stability and reliability of the packaged product. This invention, through the formulation and preparation method of the aforementioned epoxy composition, can obtain an epoxy resin composition that meets the requirements of wide-panel SOT23 packaging. Beneficial effects:

[0078] This invention provides a high-flowability epoxy resin composition and its application in wide-pack SOT23 packaging, which has the following advantages:

[0079] (1) This invention significantly improves the flowability of epoxy encapsulation materials by adding low-viscosity, high-toughness resin. This improvement makes the material easier to fill the mold during the encapsulation process, reduces wire breakage, and thus improves encapsulation quality and production efficiency.

[0080] (2) As electronic products become increasingly miniaturized and complex, the performance requirements for packaging materials are also becoming higher. The epoxy molding compound designed in this invention can pass the stringent test of moisture sensitivity level MSL1, ensuring the stability and reliability of the product in a humid environment. This breakthrough provides a material basis for downstream manufacturers to provide higher quality packaging materials, meeting the market's demand for high-performance and high-reliability electronic products.

[0081] (3) The epoxy encapsulation material of the present invention performs excellently in customer applications, particularly in terms of anti-fraying and anti-delamination. Thanks to the enhanced material flowability and improved anti-delamination ability, devices encapsulated using the material of the present invention can significantly reduce the occurrence of fraying and delamination problems, thereby improving the overall performance of the product and user satisfaction.

[0082] (4) The epoxy resin composition prepared by the present invention has a viscosity (at 175°C) as low as 10 Pa·s and a flexural modulus (at 260°C) as low as 1000 MPa, which can well meet the application of wide-row SOT23 packaging and meet the market's urgent demand for high-efficiency and low-cost packaging solutions.

[0083] (5) The enhanced flowability of the epoxy resin composition of the present invention also helps to reduce energy consumption and cost in the encapsulation process, resulting in significant economic benefits. Detailed Implementation

[0084] Note: Unless otherwise specified, all raw materials used in this invention are commercially available.

[0085] Example

[0086] Examples 1-2

[0087] Examples 1-2 respectively provide an epoxy resin composition, its preparation method, and its application in wide-pack SOT23 packaging.

[0088] The formulation of the epoxy resin composition is shown in Table 1; the values ​​in Table 1 are the amounts of raw materials added, and the units are parts by weight.

[0089] Table 1 Formulations of the epoxy resin compositions in Examples 1-2 Note: In Table 1, / represents not added.

[0090] The sources of the raw materials in Table 1 are as follows.

[0091] Formula I: Sourced from Changchun Artificial Resin Factory, product model CNE-195LL.

[0092] Formula II: From Mitsubishi Chemical Corporation, product model jER YX4000.

[0093] Formula III: Sourced from Shandong Shengquan New Material Co., Ltd., product model PF8011.

[0094] Formula IV: Sourced from Hunan Jiashengde Materials Technology Co., Ltd., product model BPNH9781S.

[0095] Spherical silica: maximum particle size 75 μm, particle size D50 value 20 μm, specific surface area 2.5 m². 2 / g; sourced from Jiangsu Lianrui New Materials Co., Ltd.

[0096] Triphenylphosphine-benzoquinone adduct: specifically triphenylphosphine-1,4-benzoquinone adduct, CAS number 5405-63-0.

[0097] Brazilian carnauba wax: Supplier: NIKKO FINE Co., Ltd., product model: Nikko carnauba.

[0098] Carbon black: Supplier: Mitsubishi Chemical Corporation, product model MA600.

[0099] The preparation steps of the epoxy resin composition include:

[0100] Step 1: Use a resin pulverizer to pulverize the epoxy resin and curing agent separately, with the operating temperature controlled at 15℃; then package and seal them, and store them at low temperature for later use.

[0101] Step 2: Add inorganic fillers, catalysts, coupling agents, release agents, and colorants to a high-speed mixer in batches and mix them at an operating temperature of 15°C; then add the pulverized epoxy resin and curing agent and mix.

[0102] Step 3: Transfer the material obtained in Step 2 to a twin-screw extruder, mix and extrude at 100°C, cool and then pulverize to obtain an epoxy resin composition product. Store in a sealed container at a low temperature (below 5°C) for later use.

[0103] The ambient humidity during steps one through three is 40% RH.

[0104] Comparative Example

[0105] The sample was obtained from Jiangsu Huahai Chengke New Materials Co., Ltd., product model EMG-400.

[0106] Performance testing methods

[0107] Referring to the method of GB / T 40564-2021, the gelation time, spiral flow length, viscosity, water absorption rate and flexural modulus of the epoxy resin compositions prepared in Examples 1-2 and the comparative samples were tested, and the test results are shown in Table 2.

[0108] The test conditions for spiral flow length were 90 seconds of curing at 175℃, gelation time was 175℃, viscosity was 175℃ and tested using a capillary rheometer, water absorption was tested after 24 hours of PCT (high-pressure aging test) treatment at 121℃ and 100% RH, and flexural modulus was tested at 260℃.

[0109] Performance test results

[0110] The test results of the epoxy resin compositions obtained in Examples 1-2 are shown in Table 2.

[0111] Table 2 Performance test results of the epoxy resin compositions of Examples 1-2 and the comparative examples.

[0112] As can be seen from Table 2, the present invention, by introducing a specific epoxy resin base material (Formula II) and a specific curing agent (Formula IV) into the formulation of the epoxy resin composition, can significantly improve the viscosity and modulus of the epoxy resin molding compound. The test results of Example 2 show that its performance is superior to the comparative example, which helps improve the anti-fraying and anti-delamination capabilities of the epoxy resin composition when applied to customer-side components. However, when the epoxy resin base material (Formula II) and the specific curing agent (Formula IV) are not added, the performance of the resulting epoxy resin composition deteriorates significantly and cannot meet the requirements for wide-pack SOT23 packaging.

Claims

1. An epoxy resin composition, characterized by comprising: The raw materials of the epoxy resin composition, by weight, include: 3-20 parts epoxy resin base, 2-12 parts crosslinking agent, 45-110 parts plasticizer and 0.02-4 parts catalyst.

2. The epoxy resin composition according to claim 1, characterized in that, The epoxy resin composition satisfies one or more of the following conditions A to E: A spiral flow length is 30-65 inches, and the test conditions are curing at 175°C for 90 seconds; B gelation time is 20-45 seconds, and the test condition is 175℃; C viscosity is 4-12 Pa·s, test conditions are 175℃; D has a water absorption rate of less than 1%; The flexural modulus E is below 1200 MPa.

3. The epoxy resin composition according to claim 1, characterized in that, The epoxy resin base material has a structural formula that is a combination of one or more compounds as shown in Formula I and Formula II below; Formula I: Formula II: In Equation I, n is selected from 1 or 2.

4. The epoxy resin composition according to claim 3, characterized in that The crosslinking agent includes a phenolic resin, wherein the phenolic resin has a structural formula that is a combination of one or more compounds shown in Formula III and Formula IV below; Formula III: Formula IV: In Equations III and IV, n is independently selected from either 1 or 2.

5. The epoxy resin composition according to claim 4, characterized in that The raw materials for the epoxy resin composition also include: 0-15 parts of additives, excluding endpoint values; The additives include coupling agents, colorants, and lubricants in a mass ratio of 1:(1.1-1.7):(1.1-1.7).

6. The epoxy resin composition according to claim 5, characterized in that The lubricant includes carnauba wax.

7. The epoxy resin composition according to claim 6, characterized in that The coupling agent comprises 3-(glycidyloxypropyl)trimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-aminopropyltrimethoxysilane, in a mass ratio of 1:(0.5-1.5):(0.5-1.5).

8. The epoxy resin composition according to claim 7, characterized in that, The epoxy resin composition satisfies at least two of the following conditions A to E: A spiral flow length is 35-60 inches, and the test conditions are curing at 175°C for 90 seconds; B gelation time is 22-40 seconds, and the test condition is 175℃; C viscosity is 5-10 Pa·s, test conditions are 175℃; The water absorption rate is 0.2-0.4%; The flexural modulus E is 600-1000 MPa.

9. A method for preparing an epoxy resin composition according to any one of claims 1 to 8, characterized in that, The preparation steps of the epoxy resin composition include: Step 1: Crush the epoxy resin and crosslinking agent separately, package and seal them for later use; Step 2: Mix all raw materials except epoxy resin and crosslinking agent, then add the pulverized epoxy resin and crosslinking agent, and mix. Step 3 involves mixing the materials obtained in Step 2, followed by extrusion and cooling to obtain the epoxy resin composition product. The operating conditions for step one are: temperature below 25℃ and humidity below 50%RH.

10. The use of an epoxy resin composition according to any one of claims 1 to 8 in a wide-pack SOT23 package.

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