Packaging film, manufacturing method therefor, and filter chip packaging method

Abstract

Disclosed in the present invention are a packaging film, a manufacturing method therefor, and a filter chip packaging method. Raw materials for the packaging method comprise: 20-24 parts by mass of silicon dioxide, 24-26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-13 parts by mass of a flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 17-19 parts by mass of a curing agent, 2-5 parts by mass of a photoinitiator and 0.4-0.8 part by mass of an accelerant, the curing agent being prepared by compounding a bisphenol F benzoxazine curing agent and a dicyandiamide curing agent according to a mass ratio of 10:(7-9). The packaging film of the present invention has excellent flexibility and adhesive force, low moisture absorption rate and high heat resistance, and therefore is particularly suitable for packaging of filter chips.

Description

A packaging film, a preparation method thereof and a filter chip packaging method Technical Field

[0001] The present application relates to the field of semiconductor wafer packaging technology, and in particular to a packaging film, a preparation method thereof, and a filter chip packaging method. Background Art

[0002] The filter chip is encapsulated using a filter encapsulation film. This film covers the front of the filter chip and surrounds the cavity functional area of ​​the filter chip. The film covering the front of the filter chip acts as a protective film, while the enclosed cavity functional area forms a sealed cavity, preventing contamination such as moisture and preventing the inflow of liquid molding compound during the molding process. Films used for filter encapsulation should have excellent flexibility and adhesion, as well as low moisture absorption. Summary of the Invention

[0003] The purpose of this application is to provide a packaging film, a preparation method thereof and a filter chip packaging method. The packaging film has excellent flexibility and adhesion, as well as low moisture absorption rate and high heat resistance, and is particularly suitable for the packaging of filter chips.

[0004] To achieve the above-mentioned objectives, an embodiment of the present application provides, on the one hand, a filter packaging film, the raw materials of which include: 20-24 parts by mass of silicon dioxide, 24-26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-13 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 17-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(7-9).

[0005] As a preferred solution, the raw materials of the above-mentioned encapsulation film include:

[0006] 22-24 parts by mass of silica, 26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 18-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(8-9).

[0007] As a further preferred embodiment, the raw materials of the above-mentioned encapsulation film include: 22-24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:9.

[0008] As a further preferred embodiment, the raw materials of the above-mentioned encapsulation film include: 24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a ratio of 10:9.

[0009] In some specific embodiments, the silicon dioxide is preferably spherical silicon dioxide powder.

[0010] In some specific embodiments, the aliphatic urethane acrylate is selected from DH-3000B aliphatic urethane acrylate and / or DH-4000B aliphatic urethane acrylate.

[0011] In some specific embodiments, the flexible liquid epoxy resin is selected from EXA-4850 product and / or YX-7105 product.

[0012] Another aspect of the present application provides a method for preparing the above-mentioned encapsulation film, comprising: taking raw materials by mass and mixing them, grinding the mixed raw materials into a colloid, obtaining a glue solution by vacuum degassing, and coating the glue solution to obtain the encapsulation film.

[0013] Another aspect of the present invention provides a filter packaging method, which comprises: using the above-mentioned packaging film to package the filter chip. Specifically, the above-mentioned packaging film is covered on the front and surrounding of the filter chip.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0015] The encapsulation film of the present application has excellent flexibility and adhesion, as well as low moisture absorption and heat resistance, making it particularly suitable for encapsulating filter chips. Using the encapsulation film of the present application for encapsulating filter chips provides a simple encapsulation method, preventing contaminants such as moisture and liquid molding compound from the molding process from entering the filter chip cavity. The high glass transition temperature of the encapsulation film of the present application also provides excellent heat resistance, preventing the encapsulation film from penetrating the filter cavity at high temperatures. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and beneficial effects of this application more clear, this application is further described in detail below in conjunction with embodiments.

[0017] An embodiment of the present application provides a highly flexible encapsulation film, the raw materials of which include: 20-24 parts by mass of silicon dioxide, 24-26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-13 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 17-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(7-9).

[0018] As a preferred embodiment, the raw materials of the above-mentioned high-flexibility encapsulation film include: 22-24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 18-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(8-9); the aliphatic polyurethane acrylate is preferably DH-4000B aliphatic polyurethane acrylate.

[0019] As a further preferred embodiment, the raw materials of the above-mentioned high-flexibility encapsulation film include: 22-24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:9; the aliphatic polyurethane acrylate is preferably DH-4000B aliphatic polyurethane acrylate, and the flexible liquid epoxy resin is preferably YX-7105 resin.

[0020] As another preferred embodiment, the raw materials of the above-mentioned high-flexibility encapsulation film include: 24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is a compound of bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a ratio of 10:9; the aliphatic polyurethane acrylate is preferably DH-4000B aliphatic polyurethane acrylate, and the flexible liquid epoxy resin is preferably YX-7105 resin.

[0021] In the present application, silicon dioxide is used as an inorganic filler, mainly to reduce the internal stress and thermal expansion coefficient of the material system; the silicon dioxide is preferably spherical silicon dioxide powder.

[0022] In this application, aliphatic urethane acrylate, phenoxy resin, flexible liquid epoxy resin, and bisphenol F epoxy resin are all resin matrices. The aliphatic urethane acrylate and flexible liquid epoxy resin are used to enhance flexibility and reduce the storage modulus; the phenoxy resin is used to enhance adhesion. The aliphatic urethane acrylate can be selected from commercially available aliphatic urethane acrylates such as DH-3000B and DH-4000B, with DH-4000B being preferred. The phenoxy resin can be selected from JER1256 phenoxy resin. The flexible liquid epoxy resin can be selected from commercially available EXA-4850 series products (e.g., EXA-4850-150, EXA-4850-1000) and / or YX-7105 products, with YX-7105 being preferred, or both. When choosing EXA-4850 series products, the preferred parameters are: epoxy equivalent weight: 350-450g / eq, molecular weight: 700-900, viscosity: 25℃, 15000-100000mPa•s.

[0023] The curing agent is used to undergo a cross-linking reaction with the epoxy resin under the action of an accelerator at a certain temperature, transforming the material system from a fluid state to a solid state. In this application, both bisphenol F benzoxazine and dicyandiamide curing agents are selected as curing agents. The accelerator acts as a catalyst for the cross-linking reaction, primarily controlling the curing time. It has no effect on the performance of the material system. Conventional accelerators can be added in conventional amounts. In some embodiments, the accelerator can be an imidazole accelerator, such as 4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole. Since the aliphatic polyurethane acrylate is a photosensitive resin, a photoinitiator should also be added. A conventional photoinitiator compatible with the aliphatic polyurethane acrylate can be selected. The photoinitiator is used to initiate the photocuring of the aliphatic polyurethane acrylate under UV light. In this embodiment, the accelerator is used in an amount of 0.7-0.8 parts by weight, and the photoinitiator is used in an amount of 3 parts by weight.

[0024] An embodiment of the present application provides a method for preparing a highly flexible packaging film, comprising: taking raw materials in parts by mass and mixing them, grinding the mixed raw materials into a colloid using a bead mill, obtaining a glue liquid by vacuum degassing, and coating the glue liquid using a coating machine to obtain the packaging film of the present application.

[0025] Several examples and comparative examples are provided below. The raw materials used in the examples and comparative examples are as follows:

[0026] Silica: spherical silica, D50 particle size 0.6 μm;

[0027] Aliphatic polyurethane acrylate: DH-3000B aliphatic polyurethane acrylate, average molecular weight 13,000-18,000, 60°C viscosity 35,000-50,000 mPa•s (milliPascals·seconds); DH-4000B aliphatic polyurethane acrylate, average molecular weight 13,000-18,000, 60°C viscosity 120,000-150,000 mPa•s;

[0028] Phenoxy resin: JER1256, molecular weight 51000;

[0029] Flexible liquid epoxy resin: EXA-4850-150, epoxy equivalent weight: 450 g / eq, molecular weight: 900, viscosity: 25°C, 15,000 mPa·s; YX-7105 (also known as super-tough liquid epoxy resin): epoxy equivalent weight: 487 g / eq, viscosity: 50°C, 6,200 mPa·s;

[0030] Bisphenol F type epoxy resin: YD-8170, epoxy equivalent: 159g / eq;

[0031] Curing agent: bisphenol F benzoxazine CB4100; dicyandiamide;

[0032] Photoinitiator: Select photoinitiator 184, main component: 1-hydroxycyclohexyl phenyl ketone;

[0033] Accelerator: 4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole.

[0034] The formulations and performance parameters of the comparative examples and embodiments are shown in Tables 1-2, respectively. The testing methods for the performance parameters of the comparative examples and embodiments are as follows:

[0035] 1. Film tensile strength and elongation at break:

[0036] Cut the film material of size 10mm*50mm, also known as the spline, tear off the light release film, stick the two ends of the spline with tape, use the fixture of the universal material testing machine to clamp the tape at both ends, tear off the heavy release film, and test the tensile strength and elongation at break of the film.

[0037] 2. Moisture absorption rate:

[0038] Cut a 50mm x 50mm film and transfer it to a silicon wafer. Expose it under UV light for 20 seconds, cure it at 180°C for 1 hour, and weigh it. Then, immerse the silicon wafer vertically and completely in a glass container filled with distilled water at 25±1°C. Ensure that there are no bubbles on the surface and that it does not contact the container walls. After 24 hours of immersion, remove the wafer with tweezers, quickly blot the surface of the membrane with filter paper, and immediately weigh it. Calculate the moisture absorption rate based on the two weights.

[0039] 3. Silicon wafer adhesion:

[0040] Two pieces of 3mm*3mm film with a thickness of 25um were transferred to the silicon wafer. They were first exposed to UV light for 20 seconds and then cured at 180℃ for 1 hour. The shear bond strength was tested using a universal tensile testing machine.

[0041] 4. Tensile strength and elongation at break after curing:

[0042] The encapsulation film was first exposed to UV light for 20 seconds, then cured at 180°C for 1 hour to make a sample of 55mm*10mm*0.5mm in size. The sample was made into a dumbbell shape, and the clamps of the universal material testing machine were clamped at both ends. The tensile strength and elongation at break were tested in the block tensile mode.

[0043] Table 1 Raw material formula of comparative example

[0044]

[0045] Table 2 shows the performance parameter test values ​​corresponding to the comparative examples.

[0046]

[0047] Table 3 Raw material formula and performance parameter test values ​​of the embodiment

[0048]

[0049] Table 4 Performance parameter test values ​​of the embodiment

[0050]

[0051] The above embodiments are merely for the purpose of illustrating the embodiments and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications may be made based on the above descriptions. It is not necessary and impossible to enumerate all implementation methods here. Therefore, any obvious variations or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A packaging film, characterized in that: Its raw materials include: 20-24 parts by mass of silicon dioxide, 24-26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-13 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 17-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is compounded with bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(7-9).

2. The packaging film according to claim 1, characterized in that: Its raw materials include: 22-24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 12-15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 18-19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is compounded with bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:(8-9).

3. The packaging film according to claim 1, characterized in that: Its raw materials include: 22-24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is compounded by bisphenol F benzoxazine curing agent and dicyandiamide curing agent in a mass ratio of 10:

9.

4. The encapsulation film according to claim 1, wherein: 24 parts by mass of silicon dioxide, 26 parts by mass of aliphatic polyurethane acrylate, 15 parts by mass of phenoxy resin, 5-8 parts by mass of flexible liquid epoxy resin, 10 parts by mass of bisphenol F epoxy resin, 19 parts by mass of curing agent, 2-5 parts by mass of photoinitiator, and 0.4-0.8 parts by mass of accelerator; wherein the curing agent is compounded by bisphenol F benzoxazine curing agent and dicyandiamide curing agent in the ratio of 10:

9.

5. The encapsulation film according to any one of claims 1 to 4, characterized in that: The silicon dioxide is selected from spherical silicon dioxide powder.

6. The encapsulation film according to any one of claims 1 to 4, characterized in that: The aliphatic polyurethane acrylate is selected from DH-3000B aliphatic polyurethane acrylate and / or DH-4000B aliphatic polyurethane acrylate.

7. The encapsulation film according to any one of claims 1 to 4, characterized in that: The flexible liquid epoxy resin is selected from EXA-4850 product and / or YX-7105 product.

8. The method for preparing the encapsulation film according to any one of claims 1 to 7, characterized in that: include: Raw materials are taken according to mass proportions and mixed, the mixed raw materials are ground into a colloid, and a colloid solution is obtained by vacuum degassing, and the colloid solution is coated to obtain a packaging film.

9. A filter packaging method, characterized in that: The filter chip is packaged using the packaging film described in any one of claims 1 to 7.

10. The filter packaging method according to claim 9, characterized in that: The packaging film described in any one of claims 1 to 7 is used to cover the front and surrounding areas of the filter chip.

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