KR100407209B1 - Epoxy resin composition for encapsulating semiconductor device - Google Patents

Abstract

The present invention relates to an epoxy resin composition for sealing semiconductor elements, more specifically

(1) 5.0-15.0 wt% of the multi-aromatic epoxy resin of the following formula (1),

(2) an amino triazine novolac curing agent of Formula 2,

Phosphorus-modified phenol novolac curing agents of formula 3 or mixtures thereof

2.0-8.0 wt%,

(3) a silicone compound of Formula 4 and Formula 5

0.1-2.5% by weight of mixed non-halogen-based flame retardant,

(4) 0.2-0.6 weight% of coupling agents,

(5) 0.1 to 0.3% by weight curing accelerator and

(6) Inorganic filler 74.0-90.0 weight%

It relates to an epoxy resin composition for sealing a semiconductor device comprising, the epoxy resin composition of the present invention can achieve excellent flame resistance without using a flame retardant that generates by-products harmful to humans and the environment during combustion, in addition to moisture resistance, It has the advantage of excellent heat resistance and moldability.

(N in the formula is 0-7)

(N in the formula is 0-7)

(Wherein R is an amino group-containing polyether group and m and n are each 1-100)

Description

Epoxy resin composition for encapsulating semiconductor device

The present invention relates to an epoxy resin composition for sealing semiconductor elements, and more particularly, to an epoxy resin composition for sealing semiconductor elements excellent in flame retardancy comprising a silicone compound and a non-halogen flame retardant.

In general, the flame retardancy of the semiconductor element sealing material is required to be about UL 94 V-0. In order to secure such flame retardancy, bromine or chlorine-based halogen flame retardants and antimony trioxide (Sb ₂ 0 ₃ ) having excellent synergistic effects are widely used as flame retardants.

However, an epoxy resin composition containing a halogen-based flame retardant or antimony trioxide has a problem in that toxic carcinogens such as dioxins and difuran are generated during incineration or fire. In particular, gases such as HBr and HCl generated during combustion of an epoxy resin composition containing a halogen-based flame retardant are toxic to humans and have a problem of causing corrosion of semiconductor chips or lead frames.

Therefore, it is urgent to develop a flame retardant semiconductor element sealing material that can solve the above problems.

An object of the present invention is to solve the problems of the prior art as described above, by using a non-halogen-based flame retardant mixed with a silicon compound, to achieve excellent flame retardancy without fear of generation of by-products harmful to humans and the environment It is providing the epoxy resin composition for semiconductor element sealing.

That is, the present invention

(1) 5.0-15.0 wt% of the multi-aromatic epoxy resin of the following formula (1),

(2) an amino triazine novolac curing agent of Formula 2,

Phosphorus-modified phenol novolac curing agents of formula 3 or mixtures thereof

2.0-8.0 wt%,

(3) a silicone compound of Formula 4 and Formula 5

0.1-2.5% by weight of mixed non-halogen-based flame retardant,

(4) 0.2-0.6 weight% of coupling agents,

(5) 0.1 to 0.3% by weight curing accelerator and

(6) Inorganic filler 74.0-90.0 weight%

It provides an epoxy resin composition for sealing a semiconductor device comprising a.

[Formula 1]

(N in the formula is 0-7)

[Formula 2]

[Formula 3]

(N in the formula is 0-7)

[Formula 4]

[Formula 5]

(Wherein R is an amino group-containing polyether group and m and n are each 1-100)

Hereinafter, the present invention will be described in more detail.

The epoxy resin composition for semiconductor encapsulation of the present invention includes a polyaromatic epoxy resin, a curing agent, a non-halogen flame retardant, a coupling agent, a curing accelerator, and an inorganic filler, which will be described in more detail below with respect to each component.

The multi-aromatic epoxy resin (hereinafter, referred to as component (1)) used in the present invention has an epoxy group equivalent of 250 to 300 and has a structure represented by the following formula (1).

[Formula 1]

(N in the formula is 0-7)

Since the said component (1) has a structure which has a biphenyl group in the middle based on a phenol skeleton, it has low water absorption rate, excellent toughness, oxidation resistance, and excellent adhesive force. In addition, the component (1) has a low crosslinking density, so that a foamed layer in the form of a rubber is formed at a high temperature during ignition. It is understood that flame retardance is ensured by the thermal decomposition resistance of the multi-aromatic structure and the stability of the foam layer by such a crosslinked structure.

The content of the component (1) is preferably 5.0 to 15.0% by weight based on the total composition, it can not achieve the object of the present invention outside the above range.

The curing agent (hereinafter referred to as component (2)) used in the present invention is a mixture of an amino triazine novolac curing agent of the following formula (2) and a modified phenol novolak curing agent of the following formula (3).

[Formula 2]

[Formula 3]

(N in the formula is 0-7)

The amino triazine novolac curing agent in component (2) contains nitrogen in the form of a triazine ring and an amino functional group, and has excellent thermal stability, moisture resistance, and adhesion to a copper lead frame. The amino triazine novolac curing agent reacts with the component (1) upon combustion to form a foam layer, and the flame layer ensures flame retardancy by blocking the transfer of surrounding oxygen and combustion heat.

Thus, although the flame retardance to some extent is ensured by the said component (1) and the said amino triazine novolak hardener, in order to further strengthen a flame retardance, in this invention, a modified phenol novolak hardener is mixed with the said triazine novolak hardener. Can be used. The modified phenol novolac curing agent is a curing agent in the form of phosphorus in the existing phenol novolak curing agent has excellent characteristics of oxidation resistance, weather resistance, heat resistance and flame retardancy.

The content of the component (2) is preferably 2.0 to 8.0% by weight based on the total composition. When the content is less than 2.0% by weight, the curing reaction may not be sufficiently performed, and the physical properties may be remarkably lowered. If the content is more than 8.0% by weight, residues are formed in the sealing material, so that the reliability is lowered and it is uneconomical. Not good.

The non-halogen-based flame retardant (hereinafter referred to as component (3)) used in the present invention is a mixture of a silicon compound of the formula (5) having a structure of the following formula (4).

[Formula 4]

[Formula 5]

(Wherein R is an amino group-containing polyether group and m and n are each 1-100)

Among the components (3), the intermediate is a compound composed of phosphorus (P) element alone, but excellent flame retardant effect can be obtained even in a small amount, but it is known that the oxygen acid and phosphine are gradually released when the amount of water and the temperature increase. Therefore, in the present invention, instead of the conventional one, a fine coating of phenol resin and aluminum hydroxide (FE-140; Phosphorus Chemical Co., Ltd.) was used. It is excellent.

In the present invention, in order to ensure more flame retardancy, a silicone compound was used together with the above as a non-halogen flame retardant. The silicone compound is an amino group-containing polyether-modified polysiloxane compound, which is widely used as an adhesive and has high stability, and is characterized by not only flame retardancy but also excellent moldability and reliability when assembling semiconductors.

The content of the component is preferably 0.1 to 2.5% by weight based on the total composition, it can not achieve the object of the present invention outside the above range.

In the present invention, as the coupling agent (hereinafter referred to as component (4)), an amine silane compound was used. The content of the component (4) is preferably 0.2 to 0.6% by weight based on the total composition. When the content is less than 0.2% by weight, the dispersibility of the composition is inferior, so that a gel is generated when kneading, and thus moldability is degraded when assembling the semiconductor.

In the present invention, as a curing accelerator (hereinafter referred to as component (5)), TPP (triphenylphosphine; triphenylphosphine) which is a phosphorus catalyst was used. The component (5) may be used alone, or may be used by mixing and melting with a curing agent to form a melt master batch. The content of the component (5) is preferably 0.1 to 0.3% by weight based on the total composition. When the content is less than 0.1% by weight it is not good because it is difficult to achieve the object of the present invention, when the content is more than 0.3% by weight is not good because an abnormality in the curing reaction may be lowered. The content of the curing accelerator can be adjusted within a predetermined content range according to the conditions of use of the epoxy resin composition of the present invention.

In the present invention, as the inorganic filler (hereinafter referred to as component (6)), fused silica having an average particle size of 0.1 to 40 µm was used. The content of the component (6) is preferably 74.0 to 90.0% by weight based on the total composition. When the content is less than 74.0% by weight, not only is it difficult to obtain sufficient strength, but it is not good to increase the possibility of corrosion of the aluminum pad due to moisture absorption, and when it exceeds 90.0% by weight, the moldability is poor due to the poor fluidity. not.

When the component 6 is directly added, there is a problem in that moldability is poor when assembling a semiconductor because dispersion is not well performed when mixing and compatibility with other components is not good. Therefore, in the present invention, such a problem is solved by coating and using the coupling agent of the component (4) to the inorganic filler of the component (6).

In addition to the components (1) to (6), colorants, modified silicone oils, carboxyl waxes, ester waxes, stress reducing agents and the like can be added to the epoxy resin composition of the present invention as necessary.

In the epoxy resin composition of the present invention, the above-mentioned components are uniformly sufficiently dry mixed using a conventional Henssel mixer or Loedige mixer, and then melt kneaded with a roll mill or kneader. It is prepared as a final tablet product through a process of cooling, grinding and grinding.

As a method of sealing a semiconductor device using the epoxy resin composition prepared as described above, a low pressure transfer molding method is most commonly used, but it can also be molded by injection or casting.

Hereinafter, the present invention will be described in more detail with reference to examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Example 1

Accurately weigh each component shown in Table 1 (error range: ± 0.1%), uniformly mix in a Henschel mixer, melt knead at 100 ° C. for 7 minutes using a 2-roll mill and air Cooled in the middle. The cooled kneaded mixture was ground using a hood mixer to prepare an epoxy resin composition. At this time, the coupling agent was added in a form coated on the inorganic filler. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 1 below.

Example 2

The above procedure was performed except that 1.72% by weight of a modified phenol novolac curing agent was added instead of reducing the amino triazine novolac curing agent from 5.56% by weight to 3.84% by weight, and the enemy was increased from 0.32% by weight to 0.40% by weight. An epoxy resin composition was prepared in the same manner as in Example 1. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 1 below.

Example 3

The above procedure was performed except that 1.18% by weight of a modified phenol novolac curing agent was added instead of reducing the amino triazine novolac curing agent from 5.56% by weight to 4.38% by weight, and the enemy was increased from 0.32% by weight to 0.50% by weight. An epoxy resin composition was prepared in the same manner as in Example 1. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 1 below.

Example 4

The above procedure was performed except that 0.65% by weight of a modified phenol novolac curing agent was added instead of reducing the amino triazine novolac curing agent from 5.56% by weight to 4.91% by weight, and an increase of 0.3% by weight from 0.62% by weight was performed. An epoxy resin composition was prepared in the same manner as in Example 1. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 1 below.

Comparative Example 1

Epoxy was prepared in the same manner as in Example 1, except that 6.40% by weight of ortho cresol novolac resin was used instead of the polyaromatic epoxy resin and 6.16% by weight of phenol novolac curing agent was used instead of the amino triazine novolac curing agent. A resin composition was prepared. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 2 below.

Comparative Example 2

6.90% by weight of ortho cresol novolac resin was used in place of polyaromatic epoxy resin and 1.18% by weight of denatured novolac curing agent was added instead of reducing amino triazine novolac curing agent from 5.56% to 4.48% by weight. Then, an epoxy resin composition was prepared in the same manner as in Example 1. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 2 below.

Comparative Example 3

The epoxy resin composition was prepared in the same manner as in Example 1, except that the polyaromatic epoxy resin was reduced from 7.00% to 6.90% by weight, and 5.66% by weight of the phenol novolac curing agent was used instead of the amino triazine novolac curing agent. Prepared. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 2 below.

Comparative Example 4

The polyaromatic epoxy resin was increased from 7.00% to 7.84% by weight and 5.34% by weight of phenol novolac curing agent was used in place of the amino triazine novolac curing agent, except that a non-halogen-based flame retardant was not used. An epoxy resin composition was prepared in the same manner as in Example 1. Physical properties were evaluated for the epoxy resin composition thus obtained, and the evaluation results are shown in Table 2 below.

Component Example 1 Example 2 Example 3 Example 4 Multiaromatic Epoxy Resin 7.00 7.00 7.00 7.00 Hardener Amino triazine novolac 5.56 3.84 4.38 4.91 Volatile Novolak 0 1.72 1.18 0.65 Curing accelerator (triphenylphosphine) 0.18 0.18 0.18 0.18 Coupling Agent (Amine Silane) 0.42 0.42 0.42 0.42 Inorganic filler (fused silica) 86.0 86.0 86.0 86.0 Non-halogen flame retardant Of 0.32 0.40 0.50 0.60 Silicone compound 0.30 0.22 0.12 0.02 Wax 0.21 0.21 0.21 0.21 Other preparation 0.01 0.01 0.01 0.01 Spiral Flow (inch) 31 28 30 32 Glass transition temperature (℃) 110.3 111.3 113.2 113.2 Flame retardant (UL 94) V-0 V-0 V-0 V-0 Formability Sticking Count 0/50 0/50 0/50 0/50 Tilt (μm) 6 6 6 7 Hygroscopicity (PCT 24 hours) 0.25 0.24 0.27 0.26 Corrosion occurrence (168 hours PCT) 0/50 0/50 0/50 0/50

Component Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Epoxy resin Ortho Cresol Novolak 6.40 6.90 0 0 Multi-aromatic 0 0 6.90 7.84 Hardener Phenol novolac 6.16 0 5.66 5.34 Amino triazine novolac 0 4.48 0 0 Volatile Novolak 0 1.18 0 0 Curing accelerator (triphenylphosphine) 0.18 0.18 0.18 0.18 Coupling Agent (Amine Silane) 0.42 0.42 0.42 0.42 Inorganic filler (fused silica) 86.0 86.0 86.0 86.0 Non-halogen flame retardant Of 0.32 0.32 0.32 0 Silicone compound 0.30 0.30 0.30 0 Wax 0.21 0.21 0.21 0.21 Other preparation 0.01 0.01 0.01 0.01 Spiral Flow (inch) 33 38 39 33 Glass transition temperature (℃) 130.2 125.4 120.7 130.5 Flame retardant (UL 94) V-1 V-1 V-1 V-1 Formability Sticking Count 4/50 13/50 12/50 14/50 Tilt (μm) 16 24 32 21 Hygroscopicity (PCT 24 hours) 0.29 0.29 0.29 0.29 Corrosion occurrence (168 hours PCT) 7/50 8/50 4/50 9/50

[Property evaluation method]

Spiral Flow

: Mold was manufactured based on EMMI standard and flow length was evaluated under molding condition of 175 ℃ and molding pressure of 70kgf / cm2.

* Glass transition temperature

: After the test piece was produced using the bending test mold, it was measured by post-curing at 175 ° C. for 6 hours.

* Flame retardant

: It was measured by UL94 test method (vertical flame retardant test method).

* Moldability

: Assembled specimens were made in 50/44 TSOP (thin small outline package) to evaluate the number of sticking and the tilt.

* Moisture absorption rate

: Assembled specimens were made in 50/44 TSOP, post-cured at 175 ° C for 6 hours, treated with PCT (pressure cooker tester) for 2 hours at 120 ° C / 100% RH under constant temperature and humidity conditions, and then absorbed. Was evaluated.

* Corrosion

: Assembly specimens were made in 50/44 TSOP and pretreated by passing IR reflow for 10 seconds at 245 ° C. Subsequently, PCT was treated for 168 hours under constant temperature and humidity conditions of 121 ° C / 100% RH, and then the degree of corrosion of the chip pads was evaluated.

As described in detail above, the epoxy resin composition for sealing a semiconductor device of the present invention has excellent flame retardancy without using a halogen-based flame retardant that generates by-products that are harmful to human body and environment during combustion and cause corrosion of semiconductor chips and lead frames. Can be achieved. Moreover, the epoxy resin composition of this invention is excellent in moisture resistance, heat resistance, and moldability compared with the conventional resin composition.

Claims (4)

(1) 5.0-15.0 wt% of the multi-aromatic epoxy resin of the following formula (1), (2) an amino triazine novolac curing agent of Formula 2, Phosphorus-modified phenol novolac curing agents of formula 3 or mixtures thereof 2.0-8.0 wt%, (3) a silicone compound of Formula 4 and Formula 5 0.1-2.5% by weight of mixed non-halogen-based flame retardant, (4) 0.2-0.6 weight% of coupling agents, (5) 0.1 to 0.3% by weight curing accelerator and (6) Inorganic filler 74.0-90.0 weight% (However, the sum of the mixing ratio of each component is 100% by weight) epoxy resin composition for sealing a semiconductor device. [Formula 1] (N in the formula is 0-7) [Formula 2] [Formula 3] (N in the formula is 0-7) [Formula 4] [Formula 5] (Wherein R is an amino group-containing polyether group and m and n are each 1-100) The method of claim 1, Epoxy resin composition for semiconductor element sealing, characterized in that the epoxy group equivalent of the multi-aromatic epoxy resin is 250 ~ 300. The method of claim 1, Epoxy resin composition for sealing a semiconductor device, characterized in that the coating is coated with a phenol resin and aluminum hydroxide. The method of claim 1, The coupling agent is an amine silane compound, the curing accelerator is a triphenylphosphine-based compound, the inorganic filler is an epoxy resin composition for sealing a semiconductor device, characterized in that the average particle size of 0.1 ~ 40㎛, fused silica coated with a coupling agent .