JP2653604B2 - Thermosetting resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a glass transition point (hereinafter referred to as T).
g hereinafter) is high, with low water absorption, the present invention relates to a semiconductor encapsulating thermosetting resin composition excellent in toughness.

[0002]

2. Description of the Related Art In recent years, epoxy resin compositions have been generally used for sealing semiconductor devices such as ICs, LSIs, transistors, diodes, and the like, electronic circuits, and the like, from the viewpoint of characteristics and cost. However, the trend toward mass production of electronic components, high integration, and surface mounting has been progressing, and accordingly, requirements for sealing resins have become strict. In particular, cracks are likely to occur in the equipment due to the increase in the size of chips due to high integration, thinning of packages and solder immersion (200 to 300 ° C) during surface mounting. As a resin, heat resistance, high toughness and low water absorption are strongly desired.

[0003] Epoxy resins are currently the mainstream as semiconductor encapsulation resins. However, there is a limit in improvement of epoxy resin in terms of heat resistance and low water absorption, and a highly reliable epoxy resin after solder immersion during surface mounting has not been obtained. As a resin having high heat resistance in place of epoxy resin, maleimide resin has been attracting attention, but has a disadvantage that it has a high water absorption rate, cracks due to solder immersion during moisture absorption, and has poor reliability. In addition, as a resin having high heat resistance in place of the epoxy resin, a cyanate ester resin is known.
This resin has a high Tg and becomes a cured product having relatively low water absorption when a long press time is applied as in the case of molding a laminate. However, when this is used for short-time molding of a sealing material or the like, the curing speed is extremely slow and the releasability from the mold is poor. Increasing the amount of a curing catalyst such as nonylphenol, cobalt naphthenate, or zinc naphthenate to increase the curability causes problems such as a decrease in Tg, brittleness, and an increase in water absorption.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin for semiconductor encapsulation which has high heat resistance, high toughness, low water absorption, and excellent reliability after solder immersion. composition
To provide things .

[0005]

SUMMARY OF THE INVENTION The present invention is a thermosetting resin composition characterized by comprising a dicyanate ester compound and phenol-modified polybutadiene resin represented by the formula (1).

[0006]

Embedded image

[0007]

The dicyanate ester compound used in the present invention is represented by the formula (1). Equation (1)
Examples of preferred dicyanate ester compounds include bis (4-cyanatephenyl) methane, bis (3-methyl-4-cyanatephenyl) methane, bis (3-ethyl-4-cyanatephenyl) methane, bis (3,5 -Dimethyl-4-cyanatephenyl) methane, 1,1-bis (4-cyanatephenyl) ethane, 2,2-bis (4-cyanatephenyl) propane, 2,2-
Bis (4-cyanatephenyl) -1,1,1,3,3,3-hexafluoropropane, di (4-cyanatephenyl) ether,
(4-Cyanatephenyl) thioether, 4,4-dicyanate-diphenyl, and the like.

The phenol-modified polybutadiene resin used in the present invention is obtained by subjecting polybutadiene having a molecular weight of 300 to 2,000 to addition polymerization with phenols. If the molecular weight of polybutadiene is lower than 300, good toughness cannot be obtained,
If it is higher than 000, the heat resistance decreases.

As phenols, phenol, cresol, xylenol and the like are used. The phenol content is 5% in the phenol-modified polybutadiene resin.
It is preferable that the amount is not less than 50% by weight and not more than 50% by weight and an average of 1 to 3 added per molecule. If the phenol content is less than 5% by weight, the curability is poor, the Tg is low, and good toughness cannot be obtained. If it exceeds 50% by weight, the releasability at the time of molding is poor, and the water absorption of the molded article is increased.

The phenol-modified polybutadiene resin is preferably used in an amount of 5 to 50 parts by weight based on 100 parts by weight of the dicyanate ester compound. If the amount is less than 5 parts by weight, the curability and the releasability will be poor, and the water absorption of the molded article will also increase. Also
If it exceeds 50 parts by weight, the heat resistance is lowered and good toughness cannot be obtained.

The dicyanate ester compound and the phenol-modified polybutadiene resin are preferably heated to 100 to 200 ° C. and reacted in advance so that the melting point is 50 ° C. to 100 ° C.

The thermosetting resin composition of the present invention comprises a curing accelerator such as cobalt naphthenate and zinc naphthenate; an inorganic filler such as silica powder; a lubricant; a flame retardant; a release agent; a silane coupling agent; A molding material can be obtained by appropriately mixing and adding an agent or the like as necessary and kneading with heat.

A cured resin using the thermosetting resin composition of the present invention has a small dielectric constant and a small dielectric loss tangent, and is therefore suitable for a low dielectric constant laminated board.

[0014]

【Example】

(Examples 1 to 3) A dicyanate ester compound and a phenol-modified polybutadiene resin, and further, in Example 1, cobalt naphthenate according to the formulation in Table 1, were placed in a reaction vessel equipped with a stirrer, a vacuum distillation apparatus, and a thermometer. Heat. The reaction was performed under reduced pressure (about 20 mmHg) at 150 ° C. so that the melting point was 50 to 70 ° C. The melting point of the resulting resin is shown in Table 1.

[0015]

[Table 1]

(Comparative Example 1) Only a dicyanate ester compound was reacted in the same manner as in Example 1. The melting point of the resulting resin is shown in Table 1.

(Examples 4 to 6) According to the composition shown in Table 2, a curing accelerator, silica powder, epoxysilane and a release agent were added to the resins obtained in Examples 1 to 3, and kneaded with a hot roll. A molding material was obtained. The obtained molding material was molded at 180 ° C. for 3 minutes by transfer molding, and a molded article having good appearance was obtained. The molded article was further cured at 180 ° C. for 8 hours, and the characteristics were evaluated. Table 2 shows the results.

[0018]

[Table 2]

The molding materials of Examples 4 to 6 have high Tg,
High toughness (breaking energy) and low water absorption. Solder crack resistance in a moisture absorption treatment at 65 ° C., 95% RH and 72 hours was also good.

Comparative Example 2 A molding material was prepared in the same manner as in Example 4 using the cyanate ester resin of Comparative Example 1.
Poor curing, poor releasability, and difficulty in molding.

Comparative Example 3 A molding material was produced in the same manner as in Example 4 by using the cyanate ester resin of Comparative Example 1 and increasing the curing catalyst in order to increase the curability. Table 2 shows the results. Although the curability was improved, the releasability was not good. Tg
Is as low as an epoxy resin and not as tough. The water absorption is as large as epoxy resin. The solder crack resistance was not good either.

Comparative Example 4 A molding material was prepared in the same manner as in Example 4 using an epoxy resin. Table 2 shows the results. Tg
Is lower than Examples 1 to 3 and the water absorption is large.

[0023]

The cured product of the thermosetting resin composition according to the present invention has a high Tg, excellent toughness, and low water absorption. When this is used for semiconductor encapsulation, the semiconductor has good solder crack resistance, and is a highly reliable and excellent resin composition for semiconductor encapsulation.

Claims (2)

(57) [Claims] And a dicyanate ester compound and phenol-modified polybutadiene resin represented by claim 1 of formula (1)
A thermosetting resin composition, comprising: Embedded image 2. The thermosetting resin set according to claim 1, wherein the phenol is at least one phenol selected from the group consisting of phenol, cresol, and xylenol.
Adult .