LIQUID MOLDING COMPOUND FOR PROTECTING FIVE EDGES OF SEMICONDUCTOR CHIP AND PREPARATION METHOD THEREOF

Abstract

A liquid molding compound for protecting five edges of a semiconductor chip and a preparation method thereof are disclosed. The liquid molding compound includes 15 to 40 parts by mass of an epoxy resin, 15 to 35 parts by mass of a curing agent, 0.1 to 3 parts by mass of a curing accelerator, 4 to 15 parts by mass of a toughening agent, 75 to 150 parts by mass of an inorganic filler, and 0.1 to 5 parts by mass of a coupling agent. The epoxy resin is one or more selected from the group consisting of a bisphenol A epoxy resin, a bisphenol F epoxy resin, and a biphenyl epoxy resin. The toughening agent is an adduct of an epoxy resin and a carboxyl-terminated liquid butyronitrile rubber, and the curing agent is a phenol-formaldehyde resin. The molding compound has a low coefficient of thermal expansion (CTE).

Claims

1. A liquid molding compound for protecting five edges of a semiconductor chip, comprising the following components: TABLE-US-00003 an epoxy resin 15 to 40 parts by mass; a curing agent 15 to 35 parts by mass; a curing accelerator 0.1 to 3 parts by mass; a toughening agent 4 to 15 parts by mass; an inorganic filler 75 to 150 parts by mass; and a coupling agent 0.1 to 5 parts by mass; wherein the epoxy resin is selected from the group consisting of a bisphenol A epoxy resin and a bisphenol F epoxy resin; the toughening agent is one or more selected from the group consisting of an adduct of cyclohexanedimethanol diglycidyl ether and a carboxyl-terminated liquid butyronitrile rubber, an adduct of neopentyl glycol glycidyl ether and a carboxyl-terminated liquid butyronitrile rubber, an adduct of a bisphenol A epoxy resin and a carboxyl-terminated liquid butyronitrile rubber, and an adduct of a phenol-formaldehyde resin and a carboxyl-terminated liquid butyronitrile rubber; the curing agent is configured in a phenol-aralkyl resin; the curing accelerator is configured in an imidazole curing accelerator.

2. (canceled)

3. (canceled)

4. (canceled)

5. The liquid molding compound for protecting the five edges of the semiconductor chip according to claim 1, wherein the inorganic filler is silicon dioxide with a particle size of 0.1 μm to 30 μm.

6. The liquid molding compound for protecting the five edges of the semiconductor chip according to claim 1, wherein the coupling agent is a silane coupling agent (SCA).

7. The liquid molding compound for protecting the five edges of the semiconductor chip according to claim 6, wherein the SCA is γ-glycidoxypropyltrimethoxysilane.

8. The liquid molding compound for protecting the five edges of the semiconductor chip according to claim 1, further comprising: 0.1 to 3 parts by mass of a colorant.

9. A preparation method of the liquid molding compound for protecting the five edges of the semiconductor chip according to claim 1, comprising: mixing the epoxy resin, the curing agent, the curing accelerator, the toughening agent, the inorganic filler, and the coupling agent according to the parts by mass, grinding until a gel is obtained, and vacuum-degassing to obtain the liquid molding compound.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is a schematic diagram illustrating the edge protection of a silicon chip, where 1 represents a substrate, 2 represents a chip, and 3 represents an adhesive layer.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to make the objectives, technical solutions, and advantages of the present disclosure more comprehensible, specific implementations of the present disclosure are described in further detail below. It should be understood that the specific implementations described are merely intended to explain the present disclosure, rather than to limit the present disclosure.

[0024] The present disclosure provides a liquid molding compound for protecting five edges of a semiconductor chip, including 15 to 40 parts by mass of an epoxy resin, 15 to 35 parts by mass of a curing agent, 0.1 to 3 parts by mass of a curing accelerator, 4 to 15 parts by mass of a toughening agent, 75 to 150 parts by mass of an inorganic filler, and 0.1 to 5 parts by mass of a coupling agent. The epoxy resin is one or more selected from the group consisting of a bisphenol A epoxy resin, a bisphenol F epoxy resin, and a biphenyl epoxy resin. The toughening agent is an adduct of an epoxy resin and a carboxyl-terminated liquid butyronitrile rubber. The curing agent is a phenol-formaldehyde resin, which may preferably be a phenol-aralkyl resin, such as a commercially-available liquid phenol-formaldehyde resin product MEH-8000H.

[0025] The epoxy resin may be used preferably in 15 to 30 parts by mass or 30 to 40 parts by mass. The curing agent may be used preferably in 15 to 25 parts by mass or 25 to 35 parts by mass. The toughening agent may be used preferably in 4 to 6 parts by mass, 4 to 10 parts by mass, 6 to 10 parts by mass, 6 to 15 parts by mass, or 10 to 15 parts by mass. The inorganic filler may be used preferably in 75 to 100 parts by mass, 75 to 110 parts by mass, 75 to 150 parts by mass, 100 to 110 parts by mass, 100 to 150 parts by mass, or 110 to 150 parts by mass.

[0026] The toughening agent may specifically be selected from the group consisting of an adduct of cyclohexanedimethanol diglycidyl ether and a carboxyl-terminated liquid butyronitrile rubber CTBN1300X13 (such as a product HyPox® RM22 on the market), an adduct of neopentyl glycol glycidyl ether and a carboxyl-terminated liquid butyronitrile rubber CTBN1300X8 (such as a product HyPox® RM20 on the market), an adduct of a bisphenol A epoxy resin and a carboxyl-terminated liquid butyronitrile rubber CTBN1300X8 (such as a product HyPox® RA 840 on the market), and an adduct of a phenol-formaldehyde resin and a carboxyl-terminated liquid butyronitrile rubber CTBN1300X13 (such as a product HyPox® RA 928 on the market).

[0027] The curing accelerator may preferably be an imidazole curing accelerator, such as imidazole curing accelerators 2E4MZ, 2PZ®, and 2PHZ on the market. The curing accelerator can be used in a conventional amount. The inorganic filler can be a conventional inorganic filler, such as silicon dioxide, calcium silicate, or boron nitride, preferably silicon dioxide. The coupling agent is used for forming an organic matrix-coupling agent-inorganic matrix bonding layer to connect two materials with different properties. In the present disclosure, the coupling agent may preferably be an SCA and may specifically be γ-glycidoxypropyltrimethoxysilane. The liquid molding compound of the present disclosure may further include 0.1 to 3 parts by mass of a colorant, and the colorant is used to provide a color for the liquid molding. Specifically, a pigment, such as carbon black, can be used. The colorant is a non-essential component.

[0028] A specific preparation method of the liquid molding compound of the present disclosure includes: The epoxy resin, the curing agent, the curing accelerator, the toughening agent, the inorganic filler, and the coupling agent are mixed according to the parts by mass, ground until a gel is obtained, and vacuum-degassed to obtain the liquid molding compound.

[0029] In order to further prove the advantages of the liquid molding compound of the present disclosure, the following comparison tests are conducted. In the following examples and comparative examples, the curing agent is a mixture of a liquid phenol-formaldehyde resin MEH-8000H and methylhexahydrophthalic anhydride (MHHPA); the curing accelerator is a curing accelerator 2E4MZ on the market; the toughening agent is a product HyPox® RM22 on the market; the filler is silicon dioxide; the colorant is carbon black; and the coupling agent is γ-glycidoxypropyltrimethoxysilane.

[0030] Formulas of the examples and comparative examples are shown in Table 1. The products obtained in the examples and comparative examples are each tested for CTE1, silicon adhesion, fracture toughness, and impact strength, and test results are shown in Table 1.

[0031] In this example, the CTE1 was tested as follows: The liquid molding compound was cured at 150C/1H to prepare a sample meeting the requirements of the standard ASTM E831-2019, and then the CTE of the sample was determined. The fracture toughness K1 c was tested according to a method in the standard ASTM E1820-2015, The impact strength was tested according to a method in the standard ASTM D256-2010(R2018). The silicon adhesion was tested as follows: With reference to the standard ASTM D1002-2010, the liquid molding compound was spotted on a square area of 5 mm×5 mm on the surface of a silicon wafer, then cured at 180° C. for 1 h, and tested with a universal tensile testing machine for shear bond strength.

TABLE-US-00002 TABLE 1 Formulas and test results of the examples and comparative examples Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 1 Example 2 Bisphenol A epoxy resin / / 30 parts by 30 parts by / 30 parts by mass mass mass Bisphenol F epoxy resin 15 parts by 40 parts by / / 40 parts by / mass mass mass Liquid phenol-formaldehyde 15 parts by 35 parts by 25 parts by 25 parts by / 25 parts by resin MEH-8000H mass mass mass mass mass MHHPA / / / / 40 parts by / mass 2E4MZ 0.2 part by 0.3 part by 0.3 part by 0.3 part by 0.3 part by 0.3 part by mass mass mass mass mass mass HyPox ® RM22 6 parts by 4 parts by 10 parts by 15 parts by 4 parts by / mass mass mass mass mass Silicon dioxide 100 parts by 110 parts by 75 parts by 150 parts by 100 parts by 75 parts by mass mass mass mass mass mass γ- 0.3 part by 0.3 part by 0.2 part by 0.3 part by 0.3 part by 0.2 part by glycidoxypropyltrimethoxysilane mass mass mass mass mass mass Carbon black 0.2 part by 0.2 part by 0.2 part by 0.2 part by 0.2 part by 0.2 part by mass mass mass mass mass mass CTE1 21 24 25 22 30 30 (unit: ppm/° C.) Silicon adhesion (unit: MPa) 34 32 37 38 25 22 Fracture toughness K1c 3.6 3.5 3.8 3.9 2.9 2.3 Impact strength (unit: J/m) 178 178 181 186 154 132

[0032] It can be seen from Table 1 that, when a phenol-formaldehyde resin is used as a curing agent and an epoxy-modified butyronitrile rubber is used as a toughening agent, the molding compound has a low CTE and high silicon adhesion, fracture toughness, and impact strength, which can prevent the cracking and falling-off of the molding compound.

[0033] In view of the above-mentioned examples, it should be noted that the curing accelerator, coupling agent, and colorant in the present disclosure have no decisive influence on the properties of the liquid molding compound and can be added in conventional amounts. For the convenience of comparison, the amounts of the curing accelerator, coupling agent, and colorant in the examples remain unchanged.

[0034] The above examples are only some of the various examples of the present disclosure. Changes or modifications in different forms can be made by those skilled in the art based on the above description, and these changes or modifications derived from the essence or spirit of the present disclosure still fall within the protection scope of the present disclosure.