JP2006316032A - Silane coupling agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silane coupling agent capable of improving adhesive force to a base of a heat-resistant resin film, even when the agent is used at a low heat treatment temperature, after added to a heat-resistant resin precursor composition, and to provide a method for producing the same. <P>SOLUTION: This silane coupling agent comprises a compound produced by forming any one of a 2-(3-trialkoxysilylpropyl)succinic acid, a 2-(3-monoalkyldialkoxysilylpropyl)succinic acid, a 2-(3-monoalkoxydialkylsilylpropyl)succinic acid, and a 2-(3-trialkylsilylpropyl)succinic acid into an ester of an organic group or an amide thereof, or comprises a mixture of the compounds. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a silane coupling agent, and more particularly to a silane coupling agent suitable as a coupler component to be added to a precursor composition of a heat-resistant resin used for a surface protective film of a semiconductor device.

Conventionally, a coating film made of a heat resistant resin such as polyimide resin (hereinafter also referred to as a heat resistant resin film) has been used for a surface protective film and / or an interlayer insulating film of a semiconductor device.
In recent years, the size and size of sealing resin packages have been reduced by downsizing devices using semiconductor devices or by further increasing the integration of semiconductor devices. Further, while lead-free solder forces an increase in reflow temperature, semiconductor devices with low heat resistance have been developed. In order to meet this demand, a heat-resistant resin film that is more excellent in fine processability and mechanical properties than ever and that improves the reliability of semiconductor devices has been required.

  However, the heat-resistant resin itself known so far does not necessarily have sufficient adhesive force with a substrate such as a silicon wafer. Therefore, in order to improve the adhesion between the coating film of the heat-resistant resin and the substrate, a method of pretreating the substrate with a coupler such as a silane coupling agent, a precursor composition of the heat-resistant resin (hereinafter referred to as “the heat-resistant resin”) Or a varnish)), or a method of adding or copolymerizing a unit having adhesion to a substrate such as an organosilicon compound into the precursor of the heat-resistant resin. Yes.

Among these methods, in particular, a method of internally adding a coupler into a varnish is convenient because it is simple and can simplify the process.
As a method using such an internally added coupler, for example, a method using a silane coupling agent containing a highly reactive isocyanate group (see, for example, Patent Document 1 and Patent Document 2), a group having high polarity And a method using a silane coupling agent containing benzene (see, for example, Patent Document 3).

  However, when these internally added couplers are used, it is necessary to have compatibility with the heat-resistant resin and stability against aging of the varnish, so depending on the conditions of the heat treatment process for curing the heat-resistant resin precursor In some cases, satisfactory adhesion to the substrate could not be obtained. In particular, in order to apply the above heat-resistant resin film to a semiconductor device that is inferior in heat resistance as compared to conventional products such as MRAM, organic semiconductor, or CMOS having copper wiring that have been recently developed, It is necessary to lower the heat treatment temperature to 280 ° C. or lower.

However, under such low-temperature heat treatment conditions, sufficient heat energy cannot be applied to the heat-resistant resin film for effectively functioning the known internally added coupler, and the adhesion to the substrate is insufficient. There was something wrong. Therefore, the development of an internally added coupler that can ensure the adhesion between the heat-resistant resin film and the substrate in various processes including low-temperature heat treatment while maintaining good compatibility with the heat-resistant resin precursor and stability over time. Was desired.
JP 11-338157 A JP 2000-122299 A JP 2000-187321 A

  The present invention provides a silane coupling agent that improves the adhesion of the heat resistant resin film to the substrate even when the heat treatment temperature is low, and a method for producing the same, when added to the heat resistant resin precursor composition. With the goal.

  In order to solve the above problems, the present inventors have synthesized and studied various novel organosilicon compounds. As a result, specific compounds having a carboxyl group, an ester group and an alkoxysilyl group in one molecule, or in one molecule It has been found that a specific compound having a carboxyl group, an amide group and an alkoxysilyl group can be adapted to the purpose, and has led to the present invention.

  That is, an aspect of the present invention is a silane coupling agent characterized by comprising an organosilicon compound represented by the following general formula (1) or the following general formula (2), or a mixture of both. In the general formulas (1) and (2), the silane coupling agent is such that X is an oxygen atom and R is an ethyl group, or in general formulas (1) and (2), X is an imino group. And R is preferably a phenyl group.

(In the formula, X represents an oxygen atom or an imino group, Y1 and Y2 each independently represents an alkyl group having 1 to 10 carbon atoms, n represents an integer of 0 to 2, and R represents a monovalent organic group. Show.)
Moreover, the d of this invention makes the organosilicon compound represented by following General formula (3) react with the organic compound represented by following General formula (4), The manufacturing method of the silane coupling agent characterized by the above-mentioned It is.

(In formula, Y1 and Y2 are respectively independently a C1-C10 alkyl group, and n shows the integer of 0-2.)
R-X-H (4)
(In the formula, X represents an oxygen atom or an imino group, and R represents a monovalent organic group.)

  When added to the heat resistant resin precursor composition, the silane coupling agent of the present invention has an effect of improving the adhesion of the heat resistant resin film to the substrate even at a low heat treatment temperature. The production method of the present invention provides a simple method for producing the silane coupling agent.

Hereinafter, the present invention will be described in detail.
The silane coupling agent of the present invention comprises an organosilicon compound represented by the following general formula (1) or the following general formula (2), or a mixture of both.

(In the formula, X represents an oxygen atom or an imino group, Y1 and Y2 each independently represents an alkyl group having 1 to 10 carbon atoms, n represents an integer of 0 to 2, and R represents a monovalent organic group. Show.)
By adding such a silane coupling agent to a composition of a heat-resistant resin precursor such as a polyimide precursor composition or a polybenzoxazole precursor composition, heat treatment is performed at a relatively low temperature of 280 ° C. or less. Even when this is done, a varnish having a heat-resistant resin film with high adhesion to the substrate can be obtained.

  Examples of the silane coupling agent of the present invention include 2- (3-trimethoxysilylpropyl) succinic acid monomethyl ester, 3- (3-trimethoxysilylpropyl) succinic acid monomethyl ester, and 2- (3-methyldimethoxysilyl). Propyl) succinic acid monomethyl ester, 3- (3-methyldimethoxysilylpropyl) succinic acid monomethyl ester, 2- (3-triethoxysilylpropyl) succinic acid monoethyl ester, 3- (3-triethoxysilylpropyl) succinic acid Monoethyl ester, 2- (3-methyldiethoxysilylpropyl) succinic acid monomethyl ester, 3- (3-methyldiethoxysilylpropyl) succinic acid monomethyl ester, 2- (3-trimethoxysilylpropyl) succinic acid monophenyl Amide, 3- (3- Rimethoxysilylpropyl) succinic acid monophenylamide, 2- (3-triethoxysilylpropyl) succinic acid monophenylamide, 3- (3-triethoxysilylpropyl) succinic acid monophenylamide, 2- (3-methyldi And ethoxysilylpropyl) succinic acid monophenylamide, and 3- (3-methyldiethoxysilylpropyl) succinic acid monophenylamide, and mixtures thereof.

  When the silane coupling agent of the present invention is a mixture of two organosilicon compounds represented by the aforementioned general formula (1) and general formula (2) and having an isomer relationship with each other, it can be easily obtained by the method described later. It is preferable because it can be manufactured. In particular, a mixture of 2- (3-triethoxysilylpropyl) succinic acid monoethyl ester and 3- (3-triethoxysilylpropyl) succinic acid monoethyl ester, and 2- (3-triethoxysilylpropyl) succinic acid monoethyl ester A mixture of phenylamide and 3- (3-triethoxysilylpropyl) succinic acid monophenylamide is more preferable because of high adhesiveness.

  The silane coupling agent of the present invention can be produced by a reaction between a 3-alkoxysilylpropyl succinic anhydride represented by the following formula (3) and a compound having a hydroxyl group or an amino group.

  In addition, after reacting allyl succinic anhydride with a compound having a hydroxyl group or an amino group, hydrosilylation is performed using trialkoxysilane, or hydrosilylation is performed using trichlorosilane, and then silicon and chlorine are bonded by alcohol. It can also be produced by decomposing.

Among the above synthesis methods, the reaction between 3-alkoxysilylpropyl succinic anhydride and a compound having a hydroxyl group or an amino group is preferable because of its high yield and ease of operation. At this time, a catalyst or a reaction solvent may be used or may not be used.
Examples of the catalyst include pyridine, picoline, 2,6-lutidine, collidine, triethylamine, N-methylmorpholine, 4-N, N′-dimethylaminopyridine, isoquinoline, 1,4-diazabicyclo [2.2.2]. Examples include octane and 1,8-diazabicyclo [5.4.0] -7-undecene.

  As said reaction solvent, what dissolve | melts the organosilicon compound which is a raw material, and the silane coupling agent to produce | generate is preferable, for example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, and N, N-dimethyl Amides such as formamide, lactones such as γ-butyrolactone, sulfoxides such as dimethyl sulfoxide, ureas such as tetramethylurea, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, methyl acetate, ethyl acetate, Esters such as butyl acetate and diethyl oxalate, ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, chloroform Zen, and o- halogenated hydrocarbons such as dichlorobenzene, and hexane, may be used heptane, benzene, toluene, and hydrocarbons such as xylene.

  When at least one of the raw material organosilicon compound and the hydroxyl group or amino group-containing compound is liquid, the reaction can be carried out without solvent, and the resulting silane coupling agent can be added to the varnish as it is, and the reaction After reacting in a solvent, it can also be added to the varnish as a solution of a silane coupling agent. Furthermore, the reaction solvent can be removed to obtain a silane coupling agent. Moreover, when any raw material is solid, after reacting in a reaction solvent, it can be added to the varnish as a silane coupling agent solution, or the reaction solvent can be removed to obtain a silane coupling agent. In addition, the produced | generated silane coupling agent can also be refine | purified and used by the process of throwing into a poor solvent and collect | recovering as needed.

Examples of the compound having a hydroxyl group or amino group include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, benzyl alcohol, phenol, catechol, ethylene glycol, glycerin, and 2,2. A compound having a hydroxyl group such as bis (4-hydroxyphenyl) propane, a compound having an amino group such as methylamine, ethylamine, aniline, oxydianiline and ethanolamine, and 2,2-bis (3-amino- And compounds having both a hydroxyl group and an amino group, such as 4-hydroxyphenyl) hexafluoropropane. Among these compounds, those that are liquid under the reaction conditions can also be used as a reaction solvent.
Among these compounds having a hydroxyl group or an amino group, ethanol and aniline are preferred because the silane coupling agent obtained by the reaction has high adhesiveness.

  The silane coupling agent of this invention is used suitably as a component of a varnish. A heat-resistant resin precursor is a polymer in which a final cured film that has undergone a process such as heating has heat resistance among polymers having film-forming ability, and is a polyimide that is a precursor of a polyimide resin Examples thereof include acid, polyamic acid ester, polyamic acid amide, hydroxypolyamide which is a precursor of polybenzoxazole resin, heat-resistant polyamide resin, and cresol novolac phenol resin. Among these, it is more preferably used as a component of a varnish containing a polyimide resin precursor or a polybenzoxazole resin precursor.

In the varnish, the amount of the silane coupling agent of the present invention used is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the heat resistant resin precursor. When the silane coupling agent is 0.1 part by mass or more, the adhesion to the substrate is improved, and when it is 30 parts by mass or less, the solubility in varnish and the stability over time are good.
The varnish preferably contains a solvent in addition to the silane coupling agent and heat-resistant resin precursor of the present invention.

  Examples of the solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, Dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate And methyl-3-methoxypropionate, and the like may be used alone or in admixture.

The amount of the solvent in the varnish varies depending on the film thickness of the target heat resistant resin film, and is preferably in the range of 70 to 1900 parts by mass with respect to 100 parts by mass of the heat resistant resin precursor.
The usage method of the varnish containing the silane coupling agent of this invention is demonstrated. In the first application step, the varnish is applied to a support on which a heat-resistant resin film is to be formed, for example, a substrate made of silicon wafer, ceramic, aluminum, or the like. Examples of the coating method include spin coating using a spinner, spray coating using a spray coater, dipping, printing, or roll coating. In the second drying step, the coating film is dried by prebaking at 60 to 140 ° C. In the third exposure step, if the varnish is photosensitive, actinic radiation is applied to the desired pattern shape through a mask through the dried coating film. X-rays, electron beams, ultraviolet rays, visible rays, or the like can be used as actinic rays, but those having a wavelength of 200 to 500 nm are preferable. In the fourth development step, a relief pattern is obtained by dissolving and removing the irradiated portion when the varnish has a positive photosensitivity and the non-irradiated portion with a developing solution in the case of the negative type, and subsequently rinsing with a rinsing solution. . As a developing method, methods such as spraying, paddle, dipping, or ultrasonic waves are possible.

In the fifth heat treatment step, the obtained relief pattern is heat treated to obtain a heat resistant resin film. The heat treatment at this time is performed by using a hot plate, an oven, or a temperature rising oven capable of setting a temperature program. Air may be used as the atmospheric gas for the heat treatment, and an inert gas such as nitrogen or argon may be used.
In this heat treatment, a temperature of 180 ° C. or higher is applied for 5 minutes or more, and a certain constant temperature may be maintained, or the temperature may be continuously increased. The heat treatment temperature is preferably 180 to 400 ° C. More preferable heat treatment conditions are such that the maximum temperature is 200 ° C. or higher and the time of 200 ° C. or higher is 30 minutes or longer.

In addition, when using said varnish for manufacture of the semiconductor device inferior to heat resistance which cannot heat 300 degreeC or more, such as MRAM, an organic semiconductor, or CMOS which has a copper wiring, heat processing temperature shall be 180-290 degreeC. It is preferable and it is more preferable to set it as 220-250 degreeC. On the other hand, when used for manufacturing a semiconductor device that does not have a problem in heating to 300 ° C. or higher, the heat treatment temperature is more preferably 300 to 350 ° C.
When the above-mentioned heat resistant resin precursor in the varnish is not photosensitive, a relief pattern can be prepared using a photoresist after applying and drying the substrate and then performing heat treatment without exposure and development. .

  The varnish containing the silane coupling agent of the present invention can be used for manufacturing semiconductor devices. Specific preferred examples include semiconductor surface protective films, interlayer insulating films, insulating films for rewiring, and protection for flip chip devices. Examples thereof include a protective film for a device having a film or bump structure. In addition, it is also useful as an interlayer insulating film of a multilayer circuit, a cover coat of a flexible copper-clad plate, a solder resist film, or a liquid crystal alignment film.

The present invention will be described based on examples.
[Example 1]
Add 3-triethoxysilylpropyl succinic anhydride (15.22 g, 0.05 mol) to a 100 mL three-necked flask, add ethanol (2.30 g, 0.05 mol) at room temperature, and stir at 50 ° C. for 23 hours. A silane coupling agent consisting of a 55:45 mixture of 2- (3-triethoxysilylpropyl) succinic acid monoethyl ester and 3- (3-triethoxysilylpropyl) succinic acid monoethyl ester. Obtained (C-1).
The identification of the product and the calculation of the production ratio were carried out using a ¹ H-NMR chart.
¹ H-NMR (d6-DMSO) δ 0.51-0.57 (2H, m), 1.10-1.18 (12H, m), 1.26-1.40 (2H, m), 41-1.51 (0.9H, m), 1.51-1.64 (1.1H, m), 2.32-2.41 (1H, m), 2.45-2.56 (1H M), 2.59-2.70 (1H, m), 3.67-3.76 (6H, m), 4.00-4.08 (2H, m), 12.21 (1H, br) )

[Example 2]
In a three-necked flask with a capacity of 100 mL, 15.22 g (0.05 mol) of 3-triethoxysilylpropyl succinic anhydride was added, and 4.66 g (0.05 mol) of aniline was added dropwise while cooling in an ice bath. Silane coupling consisting of a 30:70 mixture of 2- (3-triethoxysilylpropyl) succinic acid monophenylamide and 3- (3-triethoxysilylpropyl) succinic acid monophenylamide by reacting with stirring for a period of time An agent was obtained (C-2).
The identification of the product and the calculation of the production ratio were carried out using a ¹ H-NMR chart.
¹ H-NMR (d6-DMSO) δ 0.54-0.61 (2H, m), 1.04-1.17 (9H, m), 1.27-1.43 (2H, m), 45-1.67 (2H, m), 2.26-2.45 (1H, m), 2.53-2.68 (1H, m), 2.71-2.86 (1H, m), 3.65-3.78 (6H, m), 6.97-7.05 (1H, t), 7.23-7.31 (2H, t), 7.54-7.64 (2H, m ), 9.93 (1.4H, s), 9.95 (0.6H, s), 12.13 (1H, br)

<Synthesis of heat resistant resin precursor>
[Reference Example 1]
In a separable flask having a volume of 5 L, 43.64 g (1.181 mol) of 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane, 59.33 g (0.75 mol) of pyridine, and 151.24 g of DMAc Was dissolved by mixing and stirring at room temperature (25 ° C.). A solution prepared by dissolving 18.92 g (0.113 mol) of 4-methylcyclohexane-1,2-dicarboxylic anhydride in 94.6 g of GBL was added dropwise thereto from a dropping funnel. The time required for the dropwise addition was 18 minutes, and the maximum reaction solution temperature was 27 ° C.
After completion of the dropwise addition, the reaction solution was stirred at room temperature for 2 hours and analyzed by HPLC (high performance liquid chromatography), and it was confirmed that 4-methylcyclohexane-1,2-dicarboxylic anhydride had disappeared.

  Next, this was cooled to −10 ° C. with a dry ice bath, and 298.81 g (1.013 mol) of 4,4′-diphenyl ether dicarboxylic acid dichloride and 22.84 g (0.24 g) of isophthalic acid dichloride were separately added to 160.25 g of GBL. 113 mol) was dropped from the dropping funnel. The time required for the dropwise addition was 280 minutes, and the reaction solution temperature was -4 ° C. at the maximum. After completion of the dropwise addition, the dry ice bath was removed, and after stirring for 15 hours, 118.65 g (1.50 mol) of pyridine was added. The reaction solution was dropped into 24 L of water under high-speed stirring to disperse and precipitate the polymer, and this was recovered, appropriately washed with water and dehydrated, followed by vacuum drying to obtain hydroxypolyamide P-1 as a heat resistant resin precursor. Obtained. The weight average molecular weight of the thus synthesized hydroxypolyamide by GPC was 27000 in terms of polystyrene.

[Reference Example 2]
In a 2 L separable flask, 173.06 g (0.473 mol) 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane, 71.19 g (0.90 mol) pyridine, 605.71 g DMAc Was dissolved by mixing and stirring at room temperature (25 ° C.). A solution prepared by dissolving 7.39 g (0.045 mol) of 5-norbornene-2,3-dicarboxylic anhydride in 29.56 g of GBL was added dropwise thereto from a dropping funnel. The time required for the dropping was 6 minutes, and the maximum reaction solution temperature was 23 ° C.
After completion of the dropwise addition, the mixture was heated to 50 ° C. with a hot water bath and stirred for 18 hours, and then the IR spectrum of the reaction solution was measured to confirm that characteristic absorptions of imide groups at 1385 cm ⁻¹ and 1772 cm ⁻¹ appeared. Further, by reaction tracking by HPLC, the products of 2,2-bis (3-amino-4-hydroxyphenyl) -hexafluoropropane and 5-norbornene-2,3-dicarboxylic anhydride are all imides. It was confirmed.

  Next, this was cooled to −13 ° C. with an ice bath, and a solution in which 132.80 g (0.45 mol) of 4,4′-diphenyl ether dicarboxylic acid dichloride was separately dissolved in GBL664.00 g was added dropwise from a dropping funnel. did. The time required for the dropping was 140 minutes, and the maximum reaction solution temperature was −8 ° C. 24 hours after the completion of dropping, the above reaction solution is dropped into 12 L of water under high-speed stirring to disperse and precipitate the polymer, which is recovered, appropriately washed with water, dehydrated and vacuum dried to obtain a heat-resistant resin precursor. Hydroxypolyamide P-2 was obtained. The weight average molecular weight of the thus synthesized hydroxypolyamide by GPC was 23000 in terms of polystyrene.

<Preparation of varnish>
[Reference Examples 3 to 8]
5 parts by mass of the silane coupling agent (C-1 or C-2) obtained in Example 1 or 2 or 5 parts by mass of 3-triethoxysilylpropylurea (C-3), and the above Reference Example 1 or 100 parts by weight of the hydroxypolyamide (P-1 or P-2) obtained in 2 was dissolved in 210 parts by weight of GBL in the combination shown in Table 1, and then filtered through a 0.2 μm filter. 8 varnishes were prepared.

<Evaluation of heat-resistant resin film>
The varnishes obtained in Reference Examples 3 to 8 were applied on a silicon wafer by a spin coater (clean track Mark 7 manufactured by Tokyo Electron) and dried at 120 ° C. for 3 minutes to obtain a coating film having a thickness of 10 μm.
This coating film was heat-treated in an inert oven in a nitrogen atmosphere at 250 ° C. for 1 hour to form a heat resistant resin film.
A sample after forming this heat-resistant resin film (unprocessed PCT sample) and a sample obtained by treating the sample with a pressure cooker (131 ° C., 3.0 atm) for 100 hours (sample after PCT treatment) In JIS K5400), 100 squares of 1 mm square were scratched with a cutter knife, and a cellophane tape was applied from above and then peeled off. By counting the number, the adhesiveness of the heat-resistant resin film obtained by low-temperature heat treatment was evaluated, and the results are shown in Table 1.
The heat resistant resin film obtained by curing the varnish containing the silane coupling agent of the present invention showed high adhesion to the silicon wafer even after the PCT treatment.

  The silane coupling agent of the present invention includes a semiconductor device surface protective film, an interlayer insulating film, a rewiring insulating film, a flip chip device protective film, a protective film of a device having a bump structure, an interlayer insulating film of a multilayer circuit, It can be suitably used as a cover coat of a flexible copper-clad plate, a solder resist film, and a liquid crystal alignment film.

Claims (4)

A silane coupling agent comprising an organosilicon compound represented by the following general formula (1) or the following general formula (2), or a mixture of both.

(In the formula, X represents an oxygen atom or an imino group, Y1 and Y2 each independently represents an alkyl group having 1 to 10 carbon atoms, n represents an integer of 0 to 2, and R represents a monovalent organic group. Show.)   The silane coupling agent according to claim 1, wherein, in the general formulas (1) and (2), X is an oxygen atom and R is an ethyl group.   The silane coupling agent according to claim 1, wherein, in the general formulas (1) and (2), X is an imino group and R is a phenyl group. The silane cup according to any one of claims 1 to 3, wherein an organosilicon compound represented by the following general formula (3) is reacted with an organic compound represented by the following general formula (4). A method for producing a ring agent.

(In formula, Y1 and Y2 are respectively independently a C1-C10 alkyl group, and n shows the integer of 0-2.)
R-X-H (4)
(In the formula, X represents an oxygen atom or an imino group, and R represents a monovalent organic group.)