KR950000071B1 - Method of forming high thermostable siloxanes polyimid film - Google Patents

Abstract

The method for forming a heat resistant siloxane polyimide film comprises: (a) reacting 100 mole% tetracarboxylic anhydride of formula (I) or (I'), 80-99.99 mole% aromatic diamine of formula (II) or (II') and 0.01-20 mole% diamine siloxane of formula (III) in an organic polar mixed solvent of dimethylacetamide and N-methylpyrrolidone to make a siloxane-modified polyamic acid soln.; (b) adding a peroxy acid and a diol curing agent of formula (IV) or (IV'); and (C) coating the mixed soln. on a silicon-contg. material, and then heat treating the coated material at 100-300 deg.C under the nitrogen atmosphere. In the formulas, R1 = R2 = (substd.) benzene ring; X1 = X2 = -CO-, -O-, -SO2-, -S-, -CH2-, -C(CH3)2- or -C(CF3)2-; R3 = aliphatic or aromatic hydrocarbon; X3 = aliphatic cpd.; X4 = -C(CH3)2-, -O-, -CH2-, -S-, -SO2-; n = 1-50. The film has a good stickness to a silicon wafer, and a good heat stability.

Description

Formation method of high heat resistant siloxane polyimide membrane

The present invention relates to a method for forming a high heat-resistant siloxane polyimide film, and in particular, a method for forming a siloxane polyimide film having excellent thermal stability from 500 ° C. to 580 ° C. with excellent adhesion to silicon-containing materials such as a working cone wafer and the like. It is about.

Recently, aromatic polyimides having the following general formula (A) having excellent heat resistance, electrical insulation, low stress, and mechanical strength in surface protection films, interlayer insulating films, and bonding protection films of semiconductor devices have been used.

In the above formula, R ₁ and R ₂ are aromatic hydrocarbon groups.

However, such a conventional polyimide has a drawback in that adhesion to silicon-containing materials such as silicon wafers and glass is poor, and thus, it is difficult to sufficiently satisfy the reliability of semiconductor devices.

Therefore, as a means of improving the adhesion of such polyimide, when polyamine acid is obtained from aromatic tetracarboxylic dianhydride and diamine, the polyimide skeleton finally formed by using diaminosiloxane as part of the diamine component is used. By introducing a -Si-O-Si-bond as in the following general formula (B), a method of improving the adhesion of a silicon wafer or the like is known.

In the above formula, R ₁ and R ₂ are aromatic hydrocarbon groups, and R ₃ is an aliphatic hydrocarbon group.

However, this method has a disadvantage in that heat resistance is greatly degraded and pyrolysis gas is generated by the use of an aliphatic diamino siloxane even if the degree of adhesion can be obtained to some extent.

In the present invention, by using a newly developed siloxane-modified polyimide by reacting a polyamic acid prepared by using a siloxane diamine containing an unsaturated bond with a peroxy acid compound, it has high adhesion to silicon-containing materials and excellent planarization characteristics. In addition, an object thereof is to provide a method for forming a siloxane polyimide film having excellent heat resistance and thermal expansion characteristics.

Hereinafter, the present invention will be described in detail.

The present invention provides 100 mol% of tetracarboxylic dianhydride of the following structural formula (I) or (I '), 80 to 99.99 mol% of aromatic diamine of the following structural formula (II) or (II'), and To prepare a polyamic acid solution by reacting the diamine siloxane of structural formula (III) with 0.01 to 20 mol%, to which peroxy acid and the diol curing agent of the following structural formula (IV) or (IV ') are added, The mixed solution is applied onto a silicon-containing material and heat-treated at a temperature of 100 to 300 ° C. under a nitrogen atmosphere to form a highly heat-resistant polyimide membrane.

,-O-, -SO₂-,-S-,

이고, R₃는 지방족 또는 방향족 탄화수소이고, X₃는 이중결합을 함유하는 지방족 화합물이고, X₄는

,-O-,-CH₂-,-S-,

n은 1내지 50의 정수이다.Wherein R ₁ and R ₂ are benzene rings or substituted benzene rings, and X ₁ and X ₂ are

, -O-, -SO ₂ -,-S-,

R ₃ is an aliphatic or aromatic hydrocarbon, X ₃ is an aliphatic compound containing a double bond, X ₄ is

, -O-,-CH ₂ -,-S-,

n is an integer of 1 to 50.

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

In order to prepare a polyamic acid solution according to the present invention, the above structural formulas are prepared in a mixed solvent of an organic polar solvent having a relatively low surface tension, such as dimethylacetamide (hereinafter referred to as DMAC) and N-methylpyrrolidone (hereinafter referred to as NMP). 50 mol% of aromatic tetracarboxylic acids of (I) or (I '), 40 to 49.99 mol% of aromatic diamines of the above formula (II) or (II'), and 0.01 to 10 diaminosiloxanes of the following formula (III) The mol% is reacted under anhydrous inert gas atmosphere.

0.5-15 mol% of peroxy acids, such as peroxy acetic acid or peroxybenzoic acid, were added to the polyamic acid solution prepared in this way, thereby preventing the unsaturated bond in the polymer chain. Make up.

The viscosity of the polyamic acid solution prepared in this way is 1500 ± 300 poise, the concentration of the solid content is suitable 20 to 25% by weight.

Subsequently, a diol compound of the above formula (IV) or (IV ′) is added as a curing agent, wherein the amount of the diol compound is used to be twice the equivalent of the diaminosiloxane.

After adding the peroxy acid and the diol hardener to the polyamic acid in this manner, the coding solution is spin-coated on a silicon-containing material such as a silicon wafer and heat-treated under a nitrogen atmosphere, but the temperature is 100 ° C., 200 ° C., 300 ° C. Heat treatment step by step for 1 hour each at to form a siloxane polyimide film.

The siloxane-modified polyimide prepared according to the present invention has a cross-linked three-dimensional structure, the molecular weight of which is very high and the thermal stability is very high thermal decomposition temperature of 500 ℃ to 580 ℃ and has the following structure.

In addition, the thermogravimetric change of the siloxane-modified polyimide prepared according to the present invention is about the same as the thermal decomposition temperature of the wholly aromatic polyimide, and contains -Si-O- containing bis-Γ-aminophenyltetramethylenedisiloxane as part of the diamine. It is 50 degreeC or more higher than polyimide.

In addition, the coefficient of thermal expansion of the conventional wholly aromatic polyimide membrane is about 4 X 10 ^-5 / ℃ at 25 to 250 ℃, but the value is about 1.5 X 10 ^-4 / ℃ rapid thermal expansion at 400 ℃, compared to the present invention The coefficient of thermal expansion of the siloxane-modified polyimide film of? Exhibits a constant value of 4 × 10 ⁻⁵ / ° C. at 25 ° C. to 450 ° C.

The low thermal expansion of the siloxane-modified polyimide film at such a high temperature is presumably because the thermal expansion of the organic component is suppressed by the three-dimensional network structure.

The adhesion of the polyimide film coated on the silicon wafer is also excellent as in the case of the conventional siloxane-containing polyimide film, and the planarization property is also very excellent, and it can be observed that the submicron space is completely planarized, And the volume resistivity has a value equivalent to that of the wholly aromatic polyimide.

Hereinafter, examples of the present invention will be described.

Example 1

22.4 g (0.1 mol) of biphenyl dianhydride, 18 g (0.09 mol) of 4,4'-diaminophenyl ether and 2.48 g (0.01 mol) of bis (3-aminopropene) tetramethyldisiloxane were 300 ml of dimethylacetyl. To the amide and 200 ml of N-methylpyrrolidone mixed solvent, the mixture was stirred at 30 ° C. and heated for 8 hours to obtain a clear and highly viscous solution.

0.5 g of benzo peroxide was added to this solution, followed by vigorous stirring to obtain an epoxy-containing siloxane modified polyamic acid solution. Solid content concentration of this solution was 14.5 weight%, the rotational viscosity in 30 degreeC was 1,800 poise, and intrinsic viscosity was 0.88.

0.8 g of bisphenol-A was added to the polyamic acid solution, followed by spin coating on a silicon wafer, followed by heat treatment at 100 ° C., 200 ° C. and 300 ° C. in a hot air dryer for 1 hour to form a polyimide film. The volume resistivity and dielectric breakdown pressure were measured.

The adhesion of the polyimide film to the wafer was measured by a peeling test with a scotch tape, and the planarization characteristics were measured by tomography using a scanning electron microscope, and the results are shown in Table 1 below.

[Examples 2 to 3]

The composition and the composition of the monomer and the crosslinking agent were changed in the same manner as in Example 1 except for changing the composition as shown in Table 1 below, and the results are shown in Table 1 below.

[Comparative Examples 1 to 3]

In Example 1, a polyimide film was formed using the composition and components shown in Table 1 without adding the siloxane-based diamine and a curing agent, and then the physical properties thereof were shown in Table 1 below.

* No additives used

Claims (4)

In an organic polar solvent, 100 mol% of tetracarboxylic dianhydride of the following structural formula (I) or (I '), 80 to 99.99 mol% of aromatic diamine of the following structural formula (II) or (II'), and the following structural formula (III) To prepare a polyamic acid solution by reacting 0.01 to 20 mol% of diamine siloxane, and peroxy acid and diol curing agent of the following formula (IV) or (IV ') are added, Is coated on a silicon-containing material and heat-treated at a temperature of 100 to 300 ° C. under a nitrogen atmosphere.

Wherein R ₁ and R ₂ are benzene rings or substituted benzene rings, and X ₁ and X ₂ are

, -O-, -SO ₂ -,-S-,-CH _2- ,

R ₃ is an aliphatic or aromatic hydrocarbon, X ₃ is an aliphatic compound containing a double bond, X ₄ is

, -O-,-CH ₂ -,-S-,

And n is an integer from 1 to 50. The method for forming a polyimide film according to claim 1, wherein 0.5 to 15 mol% of peroxyacetic acid or peroxybenzoic acid is used as the peroxy acid with respect to the polyamic acid solution. 2. The method for forming a polyimide film according to claim 1, wherein the diol curing agent is used to be twice as large as the equivalent amount of diaminosiloxane. The method for forming a polyimide film according to claim 1, wherein the heat treatment is performed stepwise at a temperature of 100 ° C, 200 ° C, and 300 ° C for 1 hour each.