JP2001192535A - Resin composition for sealing and sealed semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for sealing which does not contain a halogen (chlorine, bromine) compound and antimony oxide and is excellent in flame retardance, moldability (continuous productivity), moisture resistance, and reliability and a semiconductor device sealed therewith. SOLUTION: This resin composition essentially comprises (A) an epoxy resin, (B) a phenol resin, a flame-retardant combination of (C) a phosphazene compound with (D) a basic magnesium carbonate, and (E) an inorganic filler provided the composition contains 0.1-5 wt.%, preferably 0.5-2 wt.%, phosphazene compound, 1-10 wt.% basic magnesium carbonate, and 40-95 wt.% inorganic filler. A semiconductor chip is sealed with the composition, and the composition is cured to give a sealed semiconductor device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a halogen (chlorine,
The present invention relates to an encapsulating resin composition and a semiconductor encapsulation device having excellent flame retardancy without adding a bromine) compound and a metal oxide, and having excellent moldability, moisture resistance and reliability.

[0002]

2. Description of the Related Art In semiconductor devices, it is common to provide a sealing resin with flame retardancy. As a flame retardant formulation, a halogen (chlorine, bromine) compound and a metal oxide are used alone or in combination. Shows the flame retardant effect. Specifically, a combination of a brominated epoxy resin and antimony trioxide is generally used. However, halogen (chlorine, bromine) compounds added to exhibit the flame retardant effect of the sealing resin composition,
In particular, brominated epoxy resins and metal oxides, particularly antimony trioxide, added to assist the flame-retardant effect have the drawback of lowering the reliability of semiconductor devices. Not only that, but the negative effects on the environment have recently been pointed out.

For this reason, there has been a strong demand for the development of a sealing resin composition which is excellent in moldability, moisture resistance and reliability and does not contain a halogen (chlorine, bromine) compound and metal oxide. As a material, studies on phosphorus-based flame retardants have been widely promoted. However, many phosphorus-based flame retardants are phosphoric acid ester-based, and even if a flame-retardant effect is obtained, phosphoric acid generated by hydrolysis causes a decrease in the moisture resistance reliability of the semiconductor sealing device. Therefore, there is a disadvantage that sufficient reliability cannot be ensured. For this reason, there has been a strong demand for the development of a sealing resin composition containing no halogen (chlorine, bromine) compound and antimony oxide having excellent moldability, moisture resistance and reliability.

Also, the phosphazene compound used in the present invention is an organic substance which does not participate in the reaction except for the reaction system, which causes a problem in continuous productivity of molding and sealing, and the amount of addition is limited. In order to provide the sealing resin composition with the flame retardant effect alone, the content of the inorganic filler must be more than a certain level, so that at present, it cannot be used for the entire sealing resin composition.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned drawbacks and to meet the above-mentioned demands, and is intended to provide a novel phosphorus-nitrogen containing no halogen (chlorine, bromine) compound and antimony oxide. Molding resin composition and semiconductor with good moldability (continuous productivity), moisture resistance and reliability, while imparting sufficient flame retardancy by blending a suitable combination of a series flame retardant and basic magnesium carbonate It is intended to provide a sealing device.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result,
By the novel combination of appropriately combining the phosphazene compound and the basic magnesium carbonate, sufficient flame retardancy,
The present invention has been found to improve the moldability (continuous productivity), as well as the moisture resistance and reliability, and to achieve the above object, thereby completing the present invention.

That is, the present invention provides (A) an epoxy resin,
(B) a phenolic resin, (C) a phosphazene compound,
(D) Basic magnesium carbonate and (E) an inorganic filler are essential components, and (C)
0.1 to 5% by weight of the phosphazene compound, 1 to 10% by weight of the basic magnesium carbonate (D), and 40 to 95% by weight of the inorganic filler (E). It is a resin composition for sealing. Further, there is provided a semiconductor sealing device wherein a semiconductor chip is sealed with a cured product of the sealing resin composition.

Hereinafter, the present invention will be described in detail.

The epoxy resin (A) used in the present invention is not particularly limited in molecular structure and molecular weight as long as it is a compound having at least two epoxy groups in its molecule, and is generally used as a sealing material. Can be widely encompassed. For example, an aromatic epoxy resin such as a biphenyl type or bisphenol type, or an aliphatic epoxy resin such as a cyclohexane derivative, or an epoxy resin represented by the following general formula may be used.

[0010]

Embedded image (In the formula, R ¹ and R ² each represent a hydrogen atom or an alkyl group, and n represents an integer of 1 or more.) These epoxy resins can be used alone or in combination of two or more.

The phenolic resin (B) used in the present invention is not particularly limited as long as it has two or more phenolic hydroxyl groups capable of reacting with the epoxy resin (A). Specific examples include those shown in the following equations.

[0012]

Embedded image (Wherein, R ³ represents a hydrogen atom or an alkyl group,
n represents 0 or an integer of 1 or more, respectively.

Embedded image (Wherein, n represents 0 or an integer of 1 or more), and these resins can be used alone or in combination of two or more.

The mixing ratio of the phenol resin is such that the value of the equivalent ratio (a) / (b) between the epoxy group (a) of the epoxy resin and the phenolic hydroxyl group (b) of the phenol resin is 0.1 to 10; It is desirable to be within the range. If the equivalent ratio is less than 0.1 or more than 10, moisture resistance, heat resistance,
The molding workability and the electrical properties of the cured product are deteriorated, and both cases are not preferred. Therefore, it is better to limit to the above range.

The phosphazene compound (C) used in the present invention is represented by the following structural formula.

[0015]

Embedded image (Where R ³ is an alkoxy group, a phenoxy group,
(An organic group such as an amino group or an allyl group, and n represents an integer of 1 or more) These phosphazene compounds can be used alone or in combination of two or more. Specific examples of the phosphazene compound include, for example,

Embedded image (Where n represents a number of 3 to 4)

Embedded image (Wherein, n represents a number of 3 to 10), and from the viewpoint of heat resistance, a phosphazene compound represented by Chemical Formula 5 is particularly preferable.

The compounding ratio of the phosphazene compound is 0.1 to 5% by weight, preferably 0.1 to 5% by weight, based on the whole resin composition.
It is desirable to contain 5 to 2% by weight. This ratio is 0.
If the amount is less than 1% by weight, the flame-retardant effect cannot be sufficiently obtained, and if it exceeds 5% by weight, it oozes out on the surface of the cured product of the sealing resin and adversely affects the properties of the cured product, which is not practical. Not preferred.

The basic magnesium carbonate (D) used in the present invention is represented by the following general formula.

[0018]

## STR7 ## 3MgCO ₃ Mg (OH) ₂ .3H ₂ O The compounding ratio is desirably 1 to 10% by weight based on the whole resin composition. If the proportion is less than 1% by weight, the flame retardant effect is not sufficiently obtained, and if it exceeds 10% by weight, the flame retardant effect of the sealing resin is not improved, so the above content is appropriate.

Examples of the inorganic filler (E) used in the present invention include silica powder, alumina powder, talc, titanium oxide and glass fiber, and these can be used alone or in combination of two or more. . Among these, silica powder and alumina powder are particularly preferable, and these are often used. The inorganic filler is desirably contained in a proportion of 40 to 95% by weight based on the whole resin composition. If the proportion is less than 40% by weight, heat resistance, moisture resistance, soldering heat resistance, mechanical properties and moldability deteriorate, and if it exceeds 95% by weight, the bulk becomes large and the moldability deteriorates, which is not suitable for practical use. .

The encapsulating resin composition of the present invention contains the aforementioned epoxy resin, phenolic resin, phosphazene compound, basic magnesium carbonate and inorganic filler as main components. Further, if necessary, for example, natural waxes, synthetic waxes, linear aliphatic metal salts, acid amides, esters, paraffin-based release agents, elastomers and other low-stress components, carbon black, etc. , A treating agent for an inorganic filler such as a silane coupling agent, various curing accelerators, and the like can be appropriately added and blended.

A general method for preparing the encapsulating resin composition of the present invention as a molding material includes the above-mentioned epoxy resin, phenol resin, phosphazene compound, basic magnesium carbonate, inorganic filler, and other components. After compounding and mixing sufficiently uniformly by a mixer or the like, a melt-mixing process using a hot roll or a mixing process using a kneader or the like is performed, and then the mixture is cooled and solidified, and pulverized to an appropriate size to obtain a molding material. . When the molding material thus obtained is applied to sealing, coating, insulating, etc. of electronic parts or electric parts including semiconductor sealing, excellent properties and reliability can be imparted.

The semiconductor device of the present invention can be easily manufactured by sealing a semiconductor chip using the sealing resin obtained as described above. The most common method of sealing is low pressure transfer molding, but sealing by injection molding, compression molding, casting or the like is also possible. The sealing resin composition is heated and cured at the time of sealing, and finally a semiconductor sealing device sealed with a cured product of this composition is obtained. Curing by heating is 15
Desirably, the composition is cured by heating to 0 ° C. or higher. The semiconductor device for sealing is not particularly limited to, for example, an integrated circuit, a large-scale integrated circuit, a transistor, a thyristor, a diode, and the like.

[0023]

The resin composition for sealing and the semiconductor sealing device of the present invention can obtain desired properties by using a phosphazene compound and a basic magnesium carbonate as resin components. That is, by combining a predetermined amount of the phosphazene compound and the basic magnesium carbonate, the resin composition is provided with excellent flame retardancy while maintaining sufficient moldability, and moisture resistance in a semiconductor device is obtained from the stability of the compound. Performance and reliability can be improved.

[0024]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, “%” means “% by weight”.

Example 1 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 16%, 10% of novolak type phenol resin (phenol equivalent 105), 2% of phosphazene compound shown in Chemical formula 5, 6% of basic magnesium carbonate, 65% of fused silica powder, and 0.3% of ester wax Was mixed at room temperature, kneaded at 90 to 95 ° C., and cooled and pulverized to produce a molding material.

This molding material is transfer-injected into a mold heated to 175 ° C. and cured to form a molded product (sealed product).
Was molded. Flammability and moisture resistance of this molded product,
A continuous productivity test was performed. Table 1 shows the results.

Example 2 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 12%, 12% of novolak type phenol aralkyl resin (phenol equivalent: 175), 1.5% of the phosphazene compound shown in Chemical formula 5, 5% of basic magnesium carbonate, 68.5% of fused silica powder, and ester wax 0.3% and mixed at room temperature, and 90 ~ 9
The mixture was kneaded at 5 ° C and cooled and pulverized to produce a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 1 shows the results.

Example 3 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 11%, 6% of novolak type phenol resin (phenol equivalent 105), 1% of the phosphazene compound shown in Chemical formula 5, 6% of basic magnesium carbonate, 75% of fused silica powder and 0.2% of ester wax Was mixed at room temperature, kneaded at 90 to 95 ° C., and cooled and pulverized to produce a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 1 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 14% with a brominated epoxy resin (epoxy equivalent 2
70) 3%, 9% of novolak type phenol resin (phenol equivalent 105), 70% of fused silica powder, 1% of antimony trioxide and 0.3% of ester waxes, mixed at room temperature, and further mixed at 90 to 95 ° C. The mixture was cooled and pulverized to prepare a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 2 shows the results.

Comparative Example 2 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 15%, 9% of novolak type phenol resin (phenol equivalent 105), 3% of polyphosphate, 71% of fused silica powder and 0.3% of ester wax
Was mixed at room temperature, kneaded at 90-95 ° C., and cooled and pulverized to prepare a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 2 shows the results.

Comparative Example 3 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 17%, 10% of novolak type phenol resin (phenol equivalent 105), 71% of fused silica powder and 0.3% of ester waxes, and mixed at room temperature.
The mixture was further kneaded at 90 to 95 ° C. and cooled and pulverized to prepare a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 2 shows the results.

Comparative Example 4 Cresol novolak type epoxy resin (epoxy equivalent 2
00) 15%, 9% of novolak type phenol resin (phenol equivalent 105), 5% of the phosphazene compound shown in Chemical formula 5, 70% of fused silica powder and 0.3% of ester waxes were mixed and mixed at room temperature. , And 90-
The mixture was kneaded at 95 ° C. and cooled and pulverized to prepare a molding material.

With respect to this molding material, a molded product was obtained and various tests were performed in the same manner as in Example 1. Table 2 shows the results.

[0039]

[Table 1] 1: 120 × 12 × 3.2 by transfer molding
mm, and left at 175 ° C for 8 hours.
A flammability test was performed based on the UL-94V flame resistance test standard.

* 2: A silicon chip (test element) having two aluminum wirings was adhered to a copper frame using a molding material, and transfer molded at 175 ° C. for 2 minutes.
After making TO-92 molded product, post-curing at 175 ° C for 4 hours, solder immersion at 260 ° C, 127 ° C,
PCT was performed in 2.5 atm of saturated steam, and the disconnection due to aluminum corrosion was evaluated as defective.

* 3: The continuous productivity of DIP-14 was evaluated by transfer molding at 175 ° C. × 90 s, and the number of shots until the appearance failure of the package was counted.

[0042]

[Table 2] * 1: 120 × 12 × 3 by transfer molding.
After a molded product of 2 mm was made and left at 175 ° C. for 8 hours, a flammability test was performed based on the UL-94V flame resistance test standard.

* 2: A silicon chip (test element) having two aluminum wirings was adhered to a copper frame using a molding material, and transfer-molded at 175 ° C. for 2 minutes.
After making TO-92 molded product, post-curing at 175 ° C for 4 hours, solder immersion at 260 ° C, 127 ° C,
PCT was performed in 2.5 atm of saturated steam, and the disconnection due to aluminum corrosion was evaluated as defective.

* 3: The continuous productivity of DIP-14 was evaluated by transfer molding at 175 ° C. × 90 s, and the number of shots until the appearance failure of the package was counted.

[0045]

As is clear from the above description and Tables 1 and 2, the encapsulating resin composition and the semiconductor encapsulating apparatus of the present invention have excellent flame retardancy but are continuously manufactured. It was excellent in moisture resistance reliability without lowering the characteristics, and as a result, disconnection failure due to electrode corrosion could be significantly reduced, and long-term reliability could be guaranteed.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 85/02 C08L 85/02 H01L 23/29 H01L 23/30 R 23/31 F-term (Reference) 4J002 CC04X CD01W CD02W CD03W CD05W CD06W CE00X CQ013 DE138 DE148 DE267 DJ018 DJ048 DL008 EW156 FA048 FD018 FD133 FD136 FD137 GJ02 GQ05 4J036 AA01 AA02 AB07 AD07 AD08 AE05 AF01 AF06 FA02 FA04 FA05 FA12 EB06 EC03 EB07 EB07 EB07 EB07 FB07 EB07 ECB

Claims (2)

[Claims] 1. An epoxy resin, (B) a phenolic resin, (C) a phosphazene compound, (D) a basic magnesium carbonate and (E) an inorganic filler are essential components. 0.1 to 5% by weight of the (C) phosphazene compound, 1 to 10% by weight of the (D) basic magnesium carbonate, and 4% by weight of the (E) inorganic filler.
A sealing resin composition, which is contained at a ratio of 0 to 95% by weight. 2. An essential component comprising (A) an epoxy resin, (B) a phenolic resin, (C) a phosphazene compound, (D) a basic magnesium carbonate, and (E) an inorganic filler. 0.1 to 5% by weight of the (C) phosphazene compound, 1 to 10% by weight of the (D) basic magnesium carbonate, and 4% by weight of the (E) inorganic filler.
A semiconductor sealing device, wherein a semiconductor chip is sealed with a cured product of a sealing resin composition contained at a ratio of 0 to 95% by weight.