JP2823652B2 - Resin composition for semiconductor encapsulation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a resin composition for semiconductor encapsulation having a high glass transition point (hereinafter referred to as Tg), excellent moisture resistance, excellent compatibility, and excellent low stress characteristics. It is about.

(Prior Art) In recent years, epoxy resin compositions are generally used for sealing semiconductor elements such as ICs, LSIs, transistors, diodes, and the like, electronic circuits, and the like, from the viewpoint of characteristics, cost, and the like.

However, the trend toward mass production of electronic components, high integration, and surface mounting has been progressing, and accordingly, the demand for sealing resin has become strict.

In particular, cracks are likely to occur in the equipment due to the increase in size of chips due to high integration, thinning of packages, and solder immersion (200 to 300 ° C) during surface mounting. Low stress characteristics and heat resistance are strongly desired as a stopping resin.

Epoxy resin is currently the mainstream resin for semiconductor encapsulation, but in terms of heat resistance, improvement is limited as long as epoxy resin is used, and a highly reliable resin after solder immersion during surface mounting can be obtained. Not.

In order to cope with these solder heat resistances, it is desired that the resin has low stress, high Tg, and a temperature higher than the solder bath temperature.

As a resin having high heat resistance in place of an epoxy resin, a maleimide resin has been attracting attention, but an amine-modified maleimide resin obtained by a reaction between a bismaleimide and an aromatic diamine has excellent heat resistance during drying. However, there is a disadvantage that the water absorption is large, cracks are generated by solder immersion during moisture absorption, and the reliability is poor.

Other examples of the maleimide resin include an example in which a polymaleimide is reacted with an alkenylphenol or an alkenylphenyl ether in the presence of a polymerization catalyst (Japanese Patent Application Laid-Open No.
52-994, 58-117219, 61-95012, 62-11716, 63-230
No. 728), but there is a drawback that the cured product is inferior in low stress characteristics because the cured product is hard like the amine-modified maleimide resin.

Attempts have been made to add various silicone compounds to improve low-stress properties, but compatibility is remarkably poor, strength is reduced, water absorption is large, moisture resistance and reliability are poor, and there are many practical problems. Remains.

(Problems to be Solved by the Invention) The object of the present invention is to have good compatibility, without deteriorating general properties, excellent in moisture resistance and low stress properties,
Another object of the present invention is to provide a resin composition for semiconductor encapsulation which has high heat resistance and very excellent reliability after solder immersion.

(Means for Solving the Problems) The present invention provides: (1) (A) a propargyl etherified resin represented by the following formula [I] or / and the following formula [II]; (R ₁ : a group independently selected from —H or —CH ₃ 0 <a <100, 0 ≦ b, c <100 and a + b + c = 100 a, b, c represents the percentage of each structural unit .) (0 <d <100, 0 ≦ e, f <100 and d + e + f = 100 d, e, f indicate the percentage of each structural unit.) (B) a polysiloxane represented by the following formula [III]; _{(X: -H, CH 2 3} NH 2, -CH = CH ₂ or -CH ₂ -CH = CH ₂ Or a group n: 1 to 100 independently selected from X) (C) an epoxy resin.

(Function) The propargyl etherified resin used in the present invention is a resin having a phenolic hydroxyl group, specifically, a phenol resin, a phenol / aromatic hydrocarbon resin, for example, a phenol-modified xylene resin (Nicanol manufactured by Mitsubishi Gas Chemical Co., Ltd.) P-100), phenol aralkyl resin (Mirex XL-225, manufactured by Mitsui Toatsu Co., Ltd.), vinyl phenol resin (Marcalinker M, manufactured by Maruzen Petrochemical Co., Ltd.), or vinylphenol / styrene copolymer resin (Maruzen) Petrochemical Co., Ltd. Marca Linker CST, etc.)
Propargyl chloride or propargyl bromide is reacted with propargyl ether to give propargyl ether, which is represented by the following formula [I] or [II].

(R ₁ : a group independently selected from —H or —CH ₃ ) a, b, c and d, e, f indicate the percentage (%) of each structural unit in the formulas [I] and [II], respectively, and the portion having each structural unit in the resin as a whole [I] In the formula, a, b,
c and [II] exist in the ratio of d, e, f.
0 <a <100, 0 ≦ b, c <100 and a + b + c = 100 0 <d <100, 0 ≦ e, f <100 and d + e + f = 100. Preferably, 30 ≦ a, d ≦ 90, 10 ≦ c, f ≦ 70.

The component a or d is effective in improving heat resistance, toughness, and curability, and when the content is too small, the above-described characteristics are deteriorated. On the other hand, if the amount is too large, the c or f component decreases, so that c or f
The characteristic effects of the components being added are diminished.

The component c or f has the effect of further improving properties such as moisture resistance, low water absorption, and reliability. However, if it is too large, on the other hand, the amount of the a or d component decreases, and heat resistance, toughness, and curability decrease.

The polysiloxane used in the present invention has two or more reactive groups in the molecule, and has the following formula [II
And the degree of polymerization n is in the range of 1 to 100.

_{(X: -H, CH 2 3} NH 2, -CH = CH ₂ or -CH ₂ -CH = CH ₂ Or a group independently selected from X: n: 1 to 100) When the degree of polymerization is larger than 100, the compatibility is reduced.

Polysiloxane is a propargyl etherified resin 100
The amount is preferably 2 to 100 parts by weight based on parts by weight. If too little,
Low stress characteristics cannot be obtained. If it is too large, the mechanical strength and Tg decrease, and cracks occur during solder immersion.

It is desirable that the propargyl etherified resin and the polysiloxane are reacted in advance by using a catalyst as needed, until the melting point is in the range of 50 to 120 ° C. The catalyst for the above reaction is not particularly limited, but as an example, [II
When X in the formula [I] is -H, chloroplatinic acid or the like, which is a catalyst used for the reaction between a hydrosilyl group and an olefin, can be used. For the tertiary amine is a catalyst used for the reaction of epoxy groups with phenolic, imidazoles, and the like can be used phosphines, X is -CH = CH _2, -CH ₂ -
For CH = CH _2, it may be an organic peroxide. When X is CH _{2 3} NH _2, the reaction can be carried out by heating without using a catalyst.

As the epoxy resin, those having at least two or more epoxy groups in the molecule, for example, bisphenol A epoxy resin, bisphenol F epoxy resin,
Brominated epoxy resins, phenol novolak epoxy resins, cresol novolak epoxy resins, and other polyfunctional epoxy resins can be used.

By mixing the epoxy resin, workability, compatibility, curability is further improved, but too much heat resistance, solder crack resistance is deteriorated, preferably, based on 100 parts by weight of propargyl etherified resin, The amount is preferably 2 to 200 parts by weight, more preferably 10 to 100 parts by weight.

In order to form a molding material using the resin composition for semiconductor encapsulation of the present invention, a curing accelerator, an inorganic filler, a lubricant, a flame retardant, a release agent, a silane coupling agent, etc. are appropriately added as needed. It can be made into a material by heating and kneading.

(Example) [Synthesis of propargyl etherified product] Synthesis Examples 1 to 3 In a reaction vessel equipped with a stirrer, a reflux condenser, a thermometer, and a dropping funnel, potassium hydroxide, water / acetone were added according to the formulation in Table 1. A mixed solvent of (1/1) was added and dissolved, and a phenol / aromatic hydrocarbon resin, a vinylphenol / styrene copolymer resin or a phenol resin was added and dissolved. The solution was heated, propargyl chloride was added dropwise, and the mixture was reacted under reflux for 3 hours. Thereafter, the mixture was neutralized with hydrochloric acid, propargyl chloride unreacted with acetone was distilled off, and 1 liter of toluene was added. It was transferred to a separating funnel, washed three times with water, and the solvent was removed with an evaporator.

The propargyl etherification rate (reaction rate of phenolic hydroxyl groups) of the obtained resin is shown in Table 1.

Examples 1-2 In a reaction vessel equipped with a stirrer, a reflux condenser and a thermometer, the propargyl etherified resin of Synthesis Example 1 or Synthesis Example 2 and toluene were charged according to the formulation in Table 2 and uniformly dissolved. , A chloroplatinic acid solution was added. Dihydropolysiloxane was added thereto and reacted at 80 ° C. for 2 hours. Thereafter, the reflux condenser was replaced with a vacuum distillation apparatus to remove the solvent,
Further, the reaction was carried out at 180 ° C. for 4 hours under reduced pressure (about 20 mmHg). The resulting polysiloxane-modified propargyl etherified resin was homogeneous and the melting points are shown in Table 2.

Example 3 In a reaction vessel equipped with a stirrer, a vacuum distillation apparatus and a thermometer, the propargyl etherified resin of Synthesis Example 3 and diaminopolysiloxane were added under reduced pressure (about
The reaction was performed at 180 ° C. for 6 hours. The resulting polysiloxane-modified propargyl etherified resin was homogeneous and the melting points are shown in Table 2.

Examples 4 to 6 According to the composition shown in Table 3, the polysiloxane-modified propargyl etherified resin obtained in Examples 1 to 3 was added to an epoxy resin, an epoxy resin curing agent, a curing accelerator, silica powder, aminosilane, a colorant, A release agent was added and kneaded with a hot roll to obtain a molding material. The resulting molding material was molded by transfer molding at 180 ° C. for 3 minutes to obtain a glossy molded product without blisters. 180 more
After curing for 8 hours at ℃, properties were evaluated. The results are shown in Table 3.

The molding materials of Examples 4 to 6 using the resins of Examples 1 to 3 have lower flexural modulus at room temperature, lower stress, and lower internal stress than Comparative Example 1 containing no silicone. Moreover, the glass transition temperature is high, the bending strength at 260 ° C. is large, the heat resistance, the solder crack resistance is excellent, and the water absorption is small.

Comparative Example 1 The procedure of Example 4 was repeated except that the propargyl etherified resin of Synthesis Example 1 containing no polysiloxane was used. The appearance, bending strength and heat resistance of the molded product are good, but the bending elastic modulus is large and the solder crack resistance is not sufficient.

Comparative example 2 It carried out similarly to Example 4 using epoxy resin. Due to poor heat resistance, solder crack resistance is very poor.

Comparative example 3 It carried out similarly to Example 4 using the maleimide resin. Although the heat resistance is excellent, the flexural modulus and the water absorption are large, and the solder crack resistance is not sufficient.

Comparative Example 4 The same procedure as in Example 4 was carried out except that polysiloxane was mixed with the maleimide resin. The compatibility between the maleimide resin and the polysiloxane was poor, and the appearance of the molded article was not good. The water absorption was large and the solder crack resistance was poor.

(Effect of the Invention) The cured product of the composition using the resin for semiconductor encapsulation according to the present invention has a high Tg, and has excellent moisture resistance and strength at the time of heating, so that the sealing body has good solder crack resistance, In addition, it has low stress and excellent heat cycle resistance, and is a highly reliable and excellent resin composition for semiconductor encapsulation.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H01L 23/29 C08F 299/00 23/31 H01L 23/30 R // C08F 299/00 (56) References JP-A-3-3 215517 (JP, A) JP-A-1-276652 (JP, A) JP-A-64-40518 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 63/00-63 / 10 C08L 61/14 C08L 83/04-83/06 C08G 59/40 C08G 59/62 H01L 23/29

Claims (1)

(57) [Claims] (A) The following formula [I] and / or the following formula [I
I) a propargyl etherified resin represented by (R ₁ : a group independently selected from —H or —CH ₃ 0 <a <100, 0 ≦ b, c <100 and a + b + c = 100 a, b, c represents the percentage of each structural unit .) (0 <d <100, 0 ≦ e, f <100 and d + e + f = 100 d, e, f indicate the percentage of each structural unit.) (B) a polysiloxane represented by the following formula [III]; _{(X: -H, CH 2 3} NH 2, -CH = CH ₂ or -CH ₂ -CH = CH ₂ Or a group independently selected from X: n: 1 to 100) (C) an epoxy resin.