High-resistance resin composition for laminated chip packaging and preparation method thereof

Abstract

The invention discloses a high-resistance resin composition for packaging a laminated chip, which is prepared from the following raw materials in parts by weight: 3-10 parts of epoxy resin, 2-6 parts of a curing agent, 80-90 parts of a filling material and 1-5 parts of an auxiliary agent. The crystalline epoxy resin with the epoxy equivalent of 180-190 g / eq is adopted and matched with the tertiary amine-terminated hyperbranched polymer, so that under the condition of high filling amount, good flowability is achieved, lamination of multiple layers of chips can be achieved, the product stress is low, the reliability is high, and a gold thread is not prone to being broken when the multiple layers of chips are stacked. The fluidity of the resin composition can be further improved by matching the spherical silicon dioxide of 20 microns and 75 microns, the stress of the obtained resin composition is small, and the layering risk caused by the chip packaging reliability can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of chip packaging, and in particular to a high-resistance resin composition for stacked chip packaging and a preparation method thereof. Background Art

[0002] With the advancement of technology and the trend toward miniaturization and integration of electronic products, electronic products need to achieve higher information functions within a smaller volume, necessitating the stacking and packaging of chips. As the number of stacked chips increases, the chip bond wire arcs become longer and longer, and the requirements for the bonding wires become increasingly stringent. Improving the fluidity of the encapsulation resin can improve the packaging effect of multi-stacked chips. However, high-fluidity encapsulation resins have poor adhesion. Therefore, it is crucial to develop an encapsulation resin with high fluidity and good adhesion for multi-stacked chips.

[0003] Chinese invention patent CN101186802B discloses an epoxy resin composition for multi-chip packaging and multi-chip packaging using the composition, using a mixture of spherical fused silica with an average particle size of 5 μm or more and 30 μm or less and spherical fused silica with an average particle size of 1 μm or less as an inorganic filler, which has good moisture resistance, crack resistance, and good toughness. However, the packaging effect for multi-layer chips is not good. Chinese invention patent CN115260963B discloses a thin film adhesive for low modulus vertical stacking packaging, its preparation method and application, using a bead mill to grind the mixed raw materials into a colloid, and vacuum degassing to obtain an adhesive liquid, which has low storage modulus, high glass transition temperature, high film tensile strength, low thermal expansion coefficient, low moisture absorption rate, and high silicon wafer adhesion, but can only achieve stacked packaging of two layers of chips. As the number of chips increases, the packaging effect decreases. Summary of the Invention

[0004] In order to develop a packaging resin for multi-layer stacked chips with high fluidity and good bonding effect, the first aspect of the present invention provides a high-durability resin composition for stacked chip packaging. The preparation raw materials include 3-10 parts of epoxy resin, 2-6 parts of curing agent, 80-90 parts of filling material, and 1-5 parts of auxiliary agent, in parts by weight.

[0005] As a preferred embodiment, the raw materials for preparation include 5-10 parts of epoxy resin, 3-5 parts of curing agent, 85-90 parts of filling material, and 1-3 parts of auxiliary agent, in parts by weight.

[0006] As a preferred embodiment, in parts by weight, the raw materials for preparation include 6 parts of epoxy resin, 4 parts of curing agent, 88 parts of filling material, and 2 parts of auxiliary agent.

[0007] As a preferred embodiment, the epoxy resin includes at least epoxy resin I, and the epoxy resin I is a crystalline reducing resin, and the epoxy equivalent of the crystalline reducing resin is 150-200 g / eq.

[0008] As a preferred embodiment, the epoxy resin further includes epoxy resin II, and the epoxy resin II is a dicyclopentadiene multifunctional solid epoxy resin.

[0009] As a preferred embodiment, the weight ratio of the epoxy resin I to the epoxy resin II is (4-6):1; preferably, the weight ratio of the epoxy resin I to the epoxy resin II is 6:1.

[0010] As a preferred embodiment, the curing agent includes at least curing agent I, and the curing agent I is a hyperbranched polymer containing terminal tertiary amine groups.

[0011] As a preferred embodiment, the viscosity of the curing agent I is less than 10 mPa·s, and the gelation time is 5-15 min at 100° C. and 1 g.

[0012] As a preferred embodiment, the curing agent further comprises curing agent II, the structural formula of the curing agent II is

[0013] As a preferred embodiment, the weight ratio of the curing agent I to the curing agent II is (2-4):1; preferably, the weight ratio of the curing agent I to the curing agent II is 3:1.

[0014] The inventor found in the experiment that the crystalline epoxy resin with an epoxy equivalent of 180-190g / eq is adopted. The collocation of terminal tertiary amine group hyperbranched polymer can have good fluidity under higher filling amount, and the stacking of multilayer chips can be realized. The product stress is low and the reliability is high. The stacking of multilayer chips is not easy to break the gold wire. The possible reason for the guess is: as the stacking number of layers of the electronic chip increases, the arc between the chips is longer and longer, and the spacing between the chip lines and the lines is smaller and smaller. In order to avoid the risk brought by package reliability, it is necessary to improve the fluidity of the resin combination, and have good bonding properties simultaneously. The crystalline epoxy resin in the present invention is under preferred epoxy equivalent, and fluidity is higher at a certain temperature with the terminal tertiary amine group hyperbranched polymer. The resin combination toughness is improved, and it is possible to realize infiltration of the multilayer stacked chips, and realize good packaging effect.

[0015] As a preferred embodiment, the filling material is a spherical inorganic filling material, and the particle size of the spherical inorganic filling material is 10-100 μm.

[0016] As a preferred embodiment, the particle size of the spherical inorganic filler material includes a combination of 10-50 μm and 50-100 μm.

[0017] As a preferred embodiment, the particle size of the spherical inorganic filler includes a combination of 20 μm and 75 μm.

[0018] As a preferred embodiment, the weight ratio of the 20 μm and 75 μm spherical inorganic fillers is (10-30): (50-80).

[0019] As a preferred embodiment, the weight ratio of the 20 μm and 75 μm spherical inorganic fillers is (12-30): (58-76).

[0020] As a preferred embodiment, the spherical inorganic filler is selected from at least one of silica, alumina and talc.

[0021] As a preferred embodiment, the spherical inorganic filling material is silicon dioxide.

[0022] The inventors further discovered that the combination of 20μm and 75μm spherical silica can further improve the fluidity of the resin composition, especially when the line spacing is small. The spherical silica with a combination of large and small particle sizes can roll, which is easier to flow and encapsulate multi-layer stacked chips than flaky silica. In addition, the resin composition with a combination of large and small particle sizes has low stress, which can avoid the risk of delamination caused by chip packaging reliability.

[0023] As a preferred embodiment, the auxiliary agent includes at least one of a coupling agent, a low-stress agent, a release agent, and a colorant.

[0024] As a preferred embodiment, the coupling agent is a multifunctional silane coupling agent, and the functional group equivalent weight of the multifunctional silane coupling agent is 500-700 g / mol. Preferably, the functional group equivalent weight of the multifunctional silane coupling agent is 600 g / mol.

[0025] As a preferred embodiment, the viscosity of the multifunctional silane coupling agent is 5-10 mm 2 / s. Preferably, the viscosity of the multifunctional silane coupling agent is 8.6 mm 2 / s.

[0026] As a preferred embodiment, the low stress agent is propylene-based elastomer POE.

[0027] As a preferred embodiment, the release agent includes but is not limited to polyethylene wax; the colorant includes but is not limited to carbon black.

[0028] A second aspect of the present invention provides a method for preparing a high-resistance resin composition for stacked chip packaging, comprising the following steps:

[0029] S1: Evenly mix epoxy resin, curing agent, filling material and additives according to weight ratio;

[0030] S2 is transferred to a mixer and mixed at 90-110°C for 5-10 minutes, and then discharged;

[0031] S3 is cooled at room temperature and crushed into 1-3 mm to obtain crushed material;

[0032] S4 compacts the crushed material into a compacted shape and packs it for discharge.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The high-resistance resin composition for stacked chip packaging of the present invention adopts a crystalline epoxy resin with an epoxy equivalent of 180-190 g / eq and is combined with a terminal tertiary amine hyperbranched polymer to have good fluidity at a high filling amount, enabling the stacking of multiple chips. The product has low stress and high reliability, and the gold wire is not easily broken when the multi-layer chip is stacked.

[0035] (2) The high-resistance resin composition for stacked chip packaging of the present invention can further improve the fluidity of the resin composition by using 20 μm and 75 μm spherical silica. The obtained resin composition has low stress and can avoid the risk of delamination caused by chip packaging reliability.

[0036] (3) The high-resistance resin composition for stacked chip packaging of the present invention has high fluidity and meets the requirements of multi-layer stacked chip punching. It can also be well combined with the frame and has excellent bonding properties.

[0037] (4) The high-resistance resin composition for stacked chip packaging of the present invention has low stress and meets the reliability requirements of multi-layer chip packaging.

[0038] (5) The high-resistance resin composition for stacked chip packaging of the present invention can realize the packaging of 8-layer chips without wire punching, has a small thermal expansion coefficient, small molding shrinkage, and a large bending modulus. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of the structure calculated during the line-strike level performance test;

[0040] Figure 2 This is a real picture of a multi-stacked chip.

[0041] In the picture: 1: Gold wire; 2. Chip; 3. Frame. DETAILED DESCRIPTION

[0042] Example

[0043] A high-resistance resin composition for stacked chip packaging, calculated in parts by weight, and the raw materials for its preparation are shown in Table 1 below.

[0044] Table 1

[0045]

[0046]

[0047] The epoxy resin I is a crystalline reducing resin with an epoxy equivalent weight of 180-190 g / eq, purchased from Mitsubishi Chemical under the brand name YX-4000;

[0048] The epoxy resin II is a dicyclopentadiene multifunctional solid epoxy resin purchased from DIC with the brand name HP-7200. The curing agent I has a viscosity of less than 10 mPa·s and a gel time of 10 minutes at 100°C and 1 g. It is purchased from Shanghai Wujing Chemical Technology Co., Ltd. with the brand name QNP1-4110.

[0049] The structural formula of the curing agent II is Purchased from Shandong Shengquan, brand PF-8011;

[0050] The coupling agent is a multifunctional silane coupling agent (γ-glycidyloxypropyltrimethoxysilane) with a viscosity of 8.6 mm 2 / s, with a functional group equivalent of 600 g / mol, purchased from Xinyue Chemical with a brand name of X-12-972F; the low stress agent was purchased from ExxonMobil with a brand name of POE 3588FL.

[0051] The release agent is polyethylene wax, purchased from Hebei Tianyu Chemical Co., Ltd., brand: TY-113;

[0052] The colorant is carbon black.

[0053] The 20 μm silica is spherical in shape and is purchased from Lianrui with the brand name NQ-1240;

[0054] The 75 μm silica is spherical in shape and is purchased from Lianrui with the brand name NQ-1150.

[0055] A method for preparing a high-resistance resin composition for stacked chip packaging comprises the following steps:

[0056] S1: Evenly mix epoxy resin, curing agent, filling material and additives according to weight ratio;

[0057] S2 was transferred to a mixer and mixed at 100°C for 10 min, and then discharged;

[0058] S3 is cooled at room temperature and crushed to 2 mm to obtain crushed material;

[0059] S4 compacts the crushed material into a compacted shape and packs it for discharge.

[0060] Performance Testing

[0061] 1. Curing time: Raise the temperature of the hot plate to 175℃ and maintain ±1℃. Place 0.5-1.5g of sample on the hot plate and press it into 6cm with a flat spatula. 2 -10cm 2 Thin slices: When the sample melts and a glossy appearance appears on the surface of the melt, press the stopwatch to start timing. Use a flat spatula to scrape the sample continuously and observe or use a needle-shaped stirring rod to stir the sample continuously and observe. When the sample changes from a molten state to a gel state, stop timing and read the required time, which is the gelation time of the sample.

[0062] 2. Spiral flow length: When the mold temperature is constant at 175℃, weigh 15-25g of powdered sample and pour it into the mold cavity for injection molding. Turn it in and start timing. After the mold is automatically opened, remove the mold and open it, and read the longest continuous point length.

[0063] 3. Glass Transition Temperature: TMA: Mount the specimen on the TMA stage, start at 20°C, heat at a rate of 10°C / min, and end at 220°C. Scan to obtain the TMA test curve. Draw tangent lines above and below the transition temperature. The intersection of the two tangent lines is the glass transition temperature (Tg). 4. Thermal Expansion Coefficient: TMA: Mount the specimen on the TMA stage, start at 20°C, heat at a rate of 10°C / min, and end at 220°C. Scan to obtain the TMA test curve. Read the thermal expansion coefficient from the instrument.

[0064] 5. Molding shrinkage: Injection mold the epoxy molding compound into a sample of 120mm×15mm×10mm. After injection molding, measure the difference between the sample and the mold.

[0065] 6. Thermal conductivity: Tested according to GB / T3139-2005 standard.

[0066] 7.Flexural modulus 25℃: tested according to GB / T40564-2021 standard.

[0067] 8. Bending strength at 25°C: tested according to GB / T40564-2021.

[0068] The prepared resin composition and the multi-layer chip were injection molded and filled at 175° C., cured, and tested for the line level.

[0069] 9. Wire-cutting level: Put the product under x-ray, and the gold wire, chip, and frame will be presented relatively completely. The first connection between the gold wire and the chip is set as the first solder joint, and the connection between the gold wire and the frame is set as the second solder joint. Select the maximum wire arc, and the equipment will automatically read the value. The prepared resin composition will impact the gold wire during the injection molding process to form a wire arc. The wire arc is larger than the maximum wire arc and breaks the gold wire. The length of the straight line L between the first solder joint and the second solder joint is recorded as l, and the maximum distance from the wire arc to the straight line L is recorded as a. Wire-cutting level = a / l×100%. See the schematic diagram Figure 1 , see the actual picture Figure 2 .

[0070] The test results are shown in Table 2.

[0071] Table 2

[0072]

[0073]

Claims

1. A high-resistance resin composition for stacked chip packaging, characterized in that: In parts by weight, the raw materials include 3-10 parts of epoxy resin, 2-6 parts of curing agent, 80-90 parts of filling material and 1-5 parts of auxiliary agent.

2. The high-resistance resin composition for stacked chip packaging according to claim 1, characterized in that: The epoxy resin at least includes epoxy resin I, and the epoxy resin I is a crystalline reducing resin, and the epoxy equivalent of the crystalline reducing resin is 150-200 g / eq.

3. The high-resistance resin composition for stacked chip packaging according to claim 1, characterized in that: The curing agent at least includes curing agent I, and the curing agent I is a hyperbranched polymer with terminal tertiary amine groups.

4. The high-resistance resin composition for stacked chip packaging according to claim 3, characterized in that: The viscosity of the curing agent I is less than 10 mPa·s, and the gelling time is 5-15 min at 100° C. and 1 g.

5. The high-resistance resin composition for stacked chip packaging according to claim 1, characterized in that: The filling material is a spherical inorganic filling material, and the particle size of the spherical inorganic filling material is 10-100 μm.

6. The high-resistance resin composition for stacked chip packaging according to claim 5, characterized in that: The particle size of the spherical inorganic filler material includes a combination of 10-50 μm and 50-100 μm.

7. The high-resistance resin composition for stacked chip packaging according to claim 5, characterized in that: The spherical inorganic filling material is selected from at least one of silicon dioxide, aluminum oxide and talc.

8. The high-resistance resin composition for stacked chip packaging according to claim 1, characterized in that: The auxiliary agent includes at least one of a coupling agent, a low stress agent, a release agent, and a colorant.

9. The high-resistance resin composition for stacked chip packaging according to claim 8, characterized in that: The coupling agent is a multifunctional silane coupling agent, and the functional group equivalent of the multifunctional silane coupling agent is 500-700 g / mol.

10. A method for preparing the high-resistance resin composition for stacked chip packaging according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1 Evenly mix epoxy resin, curing agent, filling material and additive according to weight ratio; S2 is transferred to a mixer and mixed at 90-110°C for 5-10 minutes, and then discharged; S3 is cooled at room temperature and crushed to 1-3 mm to obtain crushed material; S4 compacts the crushed material into a compacted shape and packages it for discharge.

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