JPH11352701A - Rinsing liquid for photosensitive polyimide resin, and pattern forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rinsing liquid and a pattern forming method using this rinsing liquid by which a polyimide film with suppressed decrease in film properties can be obtd. even by alkali development when a photosensitive polyimide resin is used to form a pattern on a substrate. SOLUTION: This rinsing liquid is used in a cleaning process after a photosensitive polyimide resin is used to form a coating film on a substrate and then exposed and processed by an alkali development. This rinsing liquid for the photosensitive polyimide resin consists of an aq. soln. containing an acidic compd. having <=5.0 acid dissociation const. pKa measured in an aq. soln. at 25 deg.C. In the pattern forming method, the rinsing liquid above described is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rinsing solution for a photosensitive polyimide resin, and more particularly, to a method for forming a coating film on a substrate using a photosensitive polyimide resin, after exposure, developing with an alkali, and then forming a relief. The present invention relates to a rinsing liquid used for cleaning a pattern (negative residual film). Heat treatment (curing) by using the rinsing liquid of the present invention
It is possible to suppress a decrease in mechanical properties of the polyimide film formed on the substrate later. The present invention also relates to a pattern forming method using such a rinsing liquid. The rinsing liquid and the pattern forming method of the present invention can be suitably applied to the field of manufacturing semiconductor devices and the like.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor device, generally, a photoresist is peeled off when its role is finished in a process such as etching. However, when a photoresist film is used as a surface protective film or an interlayer insulating film of a semiconductor device, it is left as a permanent film, and therefore, high electrical and mechanical characteristics are required. Further, such a film is required to withstand high temperatures applied in a semiconductor manufacturing process.

In recent years, photosensitive polyimide resins have been used for such applications. Polyimide has electrical properties,
It has excellent mechanical properties and heat resistance, and is also used as a surface protective film and interlayer insulating film for semiconductor devices.To form a polyimide film selectively on fine parts, use a photosensitive polyimide resin. It is convenient to use The photosensitive polyimide resin is usually a photosensitive resin composition containing a polyamic acid or a modified product thereof, which is a precursor of polyimide, and an additive such as a photopolymerization initiator, and is uniformly dissolved or dispersed in an organic solvent. Used as As the photosensitive polyimide resin, for example, a compound obtained by introducing a photopolymerizable acryloyl group into a polyamic acid (JP-B-55-30207)
JP-B-55-41422), a compound in which a photopolymerizable acryloyl group is introduced into a polyamic acid in a salt structure (JP-B-59-52822), and a compound in which an actinic radiation functional group is introduced into a polyamic acid ( JP-A-4-70661
And JP-A-4-77741) are known. In order to form a pattern using such a photosensitive resin composition (photosensitive polyimide resin), generally, a photosensitive polyimide resin is applied on a substrate to form a coating film, and the pattern is formed on the coating film. After the exposure, the non-exposed portion is removed by development to form a relief pattern (a negative type residual film of polyamic acid), and then, if necessary, the amide acid is dehydrated and ring-closed by heat treatment to form an imidated relief. Pattern (polyimide film)
Is formed. In the case where the substrate is etched after development and then the relief pattern is peeled off, the imidization step by heat treatment can be omitted.

Conventionally, when a pattern is formed using such a photosensitive polyimide resin, it has been difficult to perform development using an alkaline aqueous solution as a developer, and an organic solvent has to be used. When an organic solvent is used as a developer, problems such as a high development cost, a need for explosion-proof equipment, a danger to the health of workers, and a pollution of the natural environment arise. Therefore, development of a photosensitive polyimide resin that can be developed with an aqueous alkali solution (alkali development) is expected.

In recent years, as a photosensitive polyimide resin which can be alkali-developed, for example, a photosensitive resin containing a compound in which a protective group capable of leaving under acid or alkali conditions is introduced into a carboxyl group or a phenolic hydroxyl group of polyamic acid. Composition (J. Macromol. Sci. Che
m. , A24, 10, 1407, 1987;
259351, JP-A-4-363361), and a photosensitive resin composition containing a photopolymerizable monomer added as a crosslinking aid (JP-A-63-183439 and JP-A-5-100424). Have been. Recently, the present inventors have found that a photosensitive resin composition containing a polyamic acid having actinic radiation functional groups introduced at both ends can be alkali-developed (Japanese Patent Application No. 9-275109).
issue). This photosensitive resin composition has good exposure sensitivity and resolution, and can be alkali-developed with an alkali developer or an aqueous alkali solution.

However, a coating film is formed on a substrate using these alkali-developable photosensitive polyimide resins,
After exposure, if alkali development is performed, even if it is washed with a normal rinsing liquid such as water, alcohol, or a mixture of water and alcohol, the tensile strength and tensile elongation of the relief pattern (polyimide film) obtained after the heat treatment are obtained. It was found that the physical properties of the film significantly decreased as compared with the intrinsic physical properties of the polyimide film. Further, the polyimide film obtained by alkali development does not have sufficient adhesion to a metal thin film such as a chromium sputtered film formed thereon. Therefore, when the photosensitive polyimide resin of the alkali development type is developed with an alkali developing solution or an aqueous alkali solution after exposure, and finally used for heat treatment to form a polyimide film, the film physical properties and adhesion are deteriorated. Is desirably suppressed.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to obtain a polyimide film in which a decrease in film properties is suppressed even when alkali development is performed when a pattern is formed on a substrate using a photosensitive polyimide resin. It is to provide a rinsing liquid that can be used. Further, an object of the present invention is to form a pattern on a substrate using a photosensitive polyimide resin,
Even when alkali development is performed, a decrease in film physical properties is suppressed, the peeling of the polyamic acid film from the substrate during rinsing is unlikely to occur, and further, a polyimide film in which a decrease in adhesion with a metal thin film or the like is suppressed is suppressed. An object of the present invention is to provide a rinse solution that can be obtained. Another object of the present invention is to provide a pattern forming method capable of forming a polyimide film in which a decrease in film physical properties and adhesion is suppressed by alkali development from a photosensitive polyimide resin using such a rinsing liquid. Is to do.

[0008] In the process of accumulating research to solve the above problems associated with alkali development, the present inventors formed a coating film on a substrate using a photosensitive polyimide resin, and after exposure, alkali development was performed. The alkali component permeates into the relief pattern (negative residual film made of polyamic acid) and is easily removed even after washing with a normal rinsing liquid such as water, alcohol, or a mixed solution of water and alcohol after development. I found that I could not do it. If a large amount of alkali component remains in the developed relief pattern formed from the photosensitive polyimide resin, during heat treatment, polyamic acid or polyimide undergoes hydrolysis, resulting in a significant decrease in molecular weight, and as a result, Physical properties such as mechanical strength of the finally obtained polyimide film are greatly reduced. This hydrolysis is presumed to be caused by the heat-induced dehydration ring-closure (imidization) reaction of the amic acid to generate water, and at this time, the presence of an alkali component. That is, it is a phenomenon peculiar to the alkali development type photosensitive polyimide resin.

Therefore, the present inventors have further studied and found that a rinsing solution to be used after alkali development is as follows.
Acid was measured in aqueous solution at 25 ° C. dissociation index pK _a of 5.0
By using an aqueous solution containing the following acidic compounds, it is possible to efficiently remove the alkali component remaining in the negative type residual film made of polyamic acid, and thereby, after heat treatment, such as tensile strength and tensile elongation. It was found that a polyimide film in which a decrease in film physical properties was suppressed was obtained. This rinsing liquid (hereinafter sometimes referred to as an acidic rinsing liquid) can effectively suppress a decrease in adhesion of the polyimide film to a metal thin film or the like. Also, when washing with an acidic rinsing liquid, depending on the cleaning treatment time and the type of the substrate, the polyamic acid film tends to peel off from the substrate, but by using an acidic rinsing liquid to which a small amount of aprotic polar solvent is added, It is possible to prevent the polyamic acid film from peeling off from the substrate during rinsing. The present invention has been completed based on these findings.

[0010]

Thus, according to the present invention, a coating film is formed on a substrate using a photosensitive polyimide resin, exposed to light, alkali-developed, and then rinsed for washing. a liquid, rinsing liquid for photosensitive polyimide resin which is characterized in that it consists of an aqueous solution in which the acid dissociation exponent pK _a, measured in aqueous solution at 25 ° C. containing 5.0 or less of the acidic compounds are provided. According to the present invention,
Form a coating film on the substrate using a photosensitive polyimide resin,
After being exposed in a pattern from the coating film, developed using an alkali developer or an aqueous alkali solution,
An acid dissociation index measured in a 25 ° C. aqueous solution as a rinsing solution in a method of forming a polyimide film pattern on a substrate by washing the relief pattern formed by development with a rinsing solution and further performing a heat treatment. pK
A pattern forming method is provided, wherein an aqueous solution containing an acidic compound having _a of 5.0 or less is used.

In the rinsing solution of the present invention, the concentration of the acidic compound in the aqueous solution is preferably in the range of 0.005 to 10.0M. The rinsing liquid of the present invention preferably contains an aprotic polar solvent in the range of 0.01 to 30% by weight in order to prevent the polyamic acid film from peeling off the substrate during rinsing. As the photosensitive polyimide resin, (A) a polyamic acid having an actinic radiation functional group, (B)
It is preferable that the photosensitive resin composition contains a photosensitive auxiliary having a photopolymerizable functional group and (C) a photopolymerization initiator, and these components are used after being uniformly dissolved or dispersed in a solvent. .

Polyamide acid is disclosed in Japanese Patent Application Laid-Open No. Hei 8-8 because it is excellent in storage stability, can be made high molecular weight, and can form a polyimide film having high sensitivity and small residual stress.
It is preferable that the compound has a structure modified with an aminobenzene or a trimellitic acid derivative having a specific structure at both ends disclosed in JP-A-2931 and JP-A-8-95247. However, since the polyamic acids specifically described in these publications are not necessarily suitable for alkali development, from the viewpoint of alkali developability, the polyamic acid may contain a carboxyl group capable of forming a salt with an alkali in a specific range. (Japanese Patent Application No. 9-275109).

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Rinse solution> In the present invention, a coating film is formed on a substrate using an alkali-developable photosensitive polyimide resin, and after exposure, developed with an alkali developer or an aqueous alkali solution. when cleaning, as a rinse, 25 ° C. of an aqueous solution the acid dissociation exponent pK _a, measured in use of an aqueous solution containing 5.0 or less of acidic compounds.
When an acidic compound having _a pKa that is too large is used, the acidity of the acidic compound is small, so that the efficiency of removing alkali components from the polyamic acid film formed in a pattern by alkali development is low, and a polyimide film formed after heat treatment. The recovery of physical properties becomes insufficient. Further, when using an aqueous solution containing an acidic compound pK _a is too large, it is necessary to increase the rinsing time in order to increase the effect of removing alkaline components prone to problems such as polyamic acid film is peeled off when rinsing.

Therefore, in the present invention, an aqueous solution containing an acidic compound having a high acidity and having _a pKa of 5.0 or less is used as a rinsing liquid in terms of the efficiency of removing alkaline components.
Here, pK _a is the dissociation constant of the acidic compound in an aqueous solution of 25 ° C., if the acidic compound has at least two dissociation stages, means a pK _a in the first stage of dissociation stage I do. As the acidic compound having _a pKa of 5.0 or less,
For example, organic carboxylic acids such as formic acid, acetic acid, lactic acid, oxalic acid, and trifluoroacetic acid; sulfonic acids such as methanesulfonic acid and p-toluenesulfonic acid; hydrochloric acid, hydrogen bromide (hydrobromic acid), and hydrogen iodide (iodine) Hydrofluoric acid), nitric acid, nitrous acid,
Inorganic acids such as sulfuric acid and sulfurous acid; and the like. These acidic compounds can be used alone or in combination of two or more.

The acidic compound is preferably one in which the required amount is uniformly dissolved in water. From the viewpoint of efficiently removing an alkali component, an acidic compound is preferably as small as possible with _a lower pKa. It is preferable that the acidic compound easily evaporate or volatilize during the heat treatment for imidization since a trace amount of the acidic compound may remain in the polyamic acid film after rinsing. That is, as the acidic compound, a compound having a low boiling point or thermal decomposition temperature and evaporating or decomposing or sublimating at a relatively low temperature is removed during the heat treatment. It is preferable because it is easy. It is preferable that the acidic compound does not adversely affect the polyimide film, the substrate, the wiring, and the like. Therefore, it is desirable to select a kind of a preferable acidic compound in consideration of these viewpoints comprehensively.

When an aqueous solution prepared using inorganic acids having _a small pKa is used as a rinsing liquid, even if the inorganic acids have a low concentration, the alkali component can be efficiently removed. That is, as inorganic acids, for example, hydrochloric acid (p
K _a = -8), hydrogen bromide (pK _a = -9), hydrogen iodide (p
K _a = -10), nitric acid (pK _a = -1.8), nitrous acid (p
K _a = 3.15), sulfuric acid (pK _a = 1.99), when using, for example, sulfite (pK _a = 1.91), it is possible to efficiently remove an alkali component. However, depending on the type of the inorganic acid, a trace amount may remain in the polyamic acid film after rinsing and adversely affect the polyimide film, wiring, substrate, and the like during heat treatment during imidization. Among inorganic acids, halides such as hydrochloric acid, hydrogen bromide, and hydrogen iodide have a risk of halogens remaining. Halogen may corrode the substrate or adversely affect the insulating property of the polyimide film. Therefore, when an inorganic acid is used as the acidic compound, it is preferable to use it at a low concentration, and if necessary, it is preferable to perform water washing after rinsing. Among the inorganic acids, nitric acid having a high acidity, containing no halogen atom, and having a low boiling point (p
K _a = −1.8; boiling point = 82.6 ° C.). However, especially for applications where a high performance polyimide film is required,
It is preferable to use organic acids as the acidic compound.

As the organic acids, those having _a small pKa are preferable from the viewpoint of the efficiency of removing alkali components, and those having a low boiling point or a low thermal decomposition temperature are preferable from the viewpoint of easy removal by heat treatment after rinsing. From these viewpoints, as the organic acids, acetic acid (pK _a = 4.56; boiling point = 118 ° C.), lactic acid (pK _a = 3.66; boiling point = 122
℃ / 14~15mmHg), formic acid (pK _a = 3.55;
Bp = 101 ° C.), oxalic acid (pK _a = 1.04; boiling point = 1
80-190 ° C), trifluoroacetic acid (pK _a =
0.23; boiling point = 72 ° C.), and lactic acid is particularly preferred. When an aqueous solution containing these organic acids is used as a rinsing liquid, it can be dried as it is after rinsing, and then subjected to a heat treatment for imidization.

Lactic acid has an appropriate acidity and exhibits a sufficient alkali removing effect. Lactic acid evaporates easily during heat treatment,
Since there is no residue in the film, the polyimide film is particularly excellent because there is almost no decrease in insulation performance and mechanical properties, and there is no fear of corrosion of metal wiring. Lactic acid is a substance in the living body, and has advantages such as high safety to the human body and little adverse effect on the natural world. The concentration of the acidic compound in the rinsing solution of the present invention can be appropriately set depending on the kind of the acidic compound, and is usually 0.005 to 10.0 M (mo).
1 / dm ³ ), preferably from 0.01 to 5.0 M, more preferably from 0.03 to 3.0 M, often 0.0 to 3.0 M.
When the concentration is about 5 to 1.0 M, the effect of removing the alkali component is sufficiently exhibited. If the concentration of the acidic compound is excessive, uniform solubility in an aqueous solution may be impaired, and the acidic compound tends to remain in the film after rinsing, which is not preferable.
If the concentration of the acidic compound is too low, the efficiency of removing the alkali component is reduced, and the effect of restoring the properties of the polyimide film is reduced.

When the washing treatment (rinsing) is performed after the alkali development using the rinsing solution of the present invention, the washing treatment time is usually from 1 second to 6 seconds, depending on the kind and concentration of the acidic compound.
0 minutes, preferably 30 to 270 seconds, more preferably 60 to 180 seconds. If the cleaning time is too short,
Alkaline components cannot be removed sufficiently. If the cleaning treatment time is too long, the polyamic acid film may be peeled off from the substrate during rinsing, and the productivity is lowered, which is not preferable. The cleaning treatment is usually performed by immersing the substrate with a polyamide film after alkali development in a rinsing liquid. Higher pK _a of the acidic compounds is less and the higher the concentration is high, even by shortening the cleaning time, it is possible to increase the removal efficiency of the alkali component. The washing (rinsing) temperature is usually 5 to 80 ° C, preferably 15 to 35 ° C, more preferably 20 to 30 ° C, and it is generally preferable to perform the washing at room temperature (around 23 ° C).

In the present invention, the type of acidic compound (pk
_a value, boiling point, etc.), concentration of acidic compounds in the aqueous solution, washing treatment time, etc.
It is possible to optimize the removal efficiency of alkali components in the polyamide film after alkali development, and as a result, it is possible to stably obtain high polyimide film physical properties (tensile strength and tensile elongation), and at the same time, to improve the film insulation performance. , And a reduction in wiring corrosiveness can be achieved. Further, by using the acidic rinsing liquid, it is possible to prevent a decrease in adhesion of the polyimide film to the metal thin film.

In the case of performing a cleaning treatment with a rinsing solution comprising an aqueous solution containing an acidic compound, a peeling phenomenon may occur at the interface between the polyamic acid film and the substrate. It is presumed that when the substrate is immersed in the acidic rinsing liquid for a long time and subjected to the cleaning treatment, the acidic rinsing liquid enters the interface between the polyamic acid film and the substrate to cause film peeling. In particular, when the substrate is a metal substrate such as a SUS substrate, the acidic rinse liquid dissolves the metal oxide film present at the interface between the polyamic acid film and the substrate, so that the polyamic acid film is easily peeled. Therefore, the present inventors have conducted studies to improve the tendency of the polyamic acid film to peel off during rinsing using an acidic rinsing liquid. Was found to be relevant.

Examples of the aprotic polar solvent include, for example,
Lactones such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, dimethylacrylamide, and γ-butyrolactone. Among these, N-methyl-2-pyrrolidone, dimethylacetamide, and γ-butyrolactone are preferred, and N-methyl-
2-Pyrrolidone and dimethylacetamide are particularly preferred. These aprotic polar solvents can be used alone or in combination of two or more. Note that the aprotic polar solvent does not include acetone or acetonitrile.

The proportion of the aprotic polar solvent to be used can be appropriately selected depending on the kind and concentration of the acidic compound, but is usually 0.1% based on the weight of (water + solvent) in the rinse solution.
01 to 30% by weight, preferably 0.05 to 15% by weight,
More preferably 0.1 to 10% by weight, most preferably 1 to 10% by weight.
~ 5% by weight. When a rinsing solution to which an aprotic polar solvent is added is used, the washing (rinsing) time depends on the type and concentration of the acidic compound, but usually ranges from 1 second to 6 hours.
0 minutes, preferably 30 to 270 seconds, more preferably 60 to 180 seconds. The cleaning (rinsing) temperature is
The temperature is 5 to 80C, preferably 15 to 35C, more preferably 20 to 30C. In general, cleaning at normal temperature (around 23 ° C.) is more preferable than cleaning at a high temperature from the viewpoint of improving film properties and adhesion.

When an acidic rinsing liquid containing an aprotic polar solvent is used, a polyamic acid film and a metal substrate (for example,
(SUS substrate) at the interface. In addition, when the rinsing liquid is used, the adhesion of the polyimide film to the metal thin film can be improved while the separation of the polyamic acid film from the substrate is suppressed. If the content ratio of the aprotic polar solvent is too small, the effect of preventing film peeling is small, and if it is too large, the effect of preventing peeling is saturated, and tends to decrease. When a solvent other than the aprotic polar solvent, for example, an alcohol or acetone is used as the solvent, there is no effect of suppressing film peeling, but rather peeling may be accelerated.

<Pattern Forming Method> The pattern forming method of the present invention comprises the following steps. A step of forming a coating film on a substrate using a photosensitive polyimide resin, a step of exposing in a pattern from the coating film, a step of developing with an alkali developer or an aqueous alkali solution, a relief pattern formed by development ( Washing the polyamic acid film with a rinsing liquid, and heat treating the polyamic acid film to form a polyimide film. In the present invention, in the step (4), 2
5 ° C. in an aqueous solution the acid dissociation exponent pK _a, measured in use of an aqueous solution containing 5.0 or less of acidic compounds. By including the aprotic polar solvent in the acidic rinsing liquid, peeling of the polyamic acid film from the substrate can be suppressed. When an organic acid such as lactic acid is used as an acidic compound component of the rinsing liquid, it can be dried after the cleaning treatment and then heat-treated (cured).

The photosensitive polyimide resin is not particularly limited as long as it is a photosensitive polyimide resin which can be alkali-developed, but (A) a polyamic acid having an actinic radiation functional group;
It is preferable to use (B) a photosensitive auxiliary having a photopolymerizable functional group and (C) a photosensitive resin composition containing a photopolymerization initiator from the viewpoint of film physical properties and adhesion. In order to form a coating film using a photosensitive polyimide resin, generally, a varnish in which each component is uniformly dissolved or dispersed in a solvent is prepared, the varnish is applied on a substrate, and dried. Examples of the substrate include a silicon wafer, a ceramic, an aluminum substrate, and a SUS substrate. The method of applying the varnish is not particularly limited, and examples thereof include a spin coating method using a spinner (spin coating method), a spray coating method using a spray coater, a dipping method, a printing method, a roll coating method, and a slit coating method. Can be mentioned.

After the varnish is applied, the coating is dried by prebaking at a low temperature of about 50 to 100 ° C. Next, the desired pattern shape is irradiated with actinic radiation from above the coating film (exposure step). As the actinic radiation, X-rays, electron beams, ultraviolet rays, visible rays and the like can be used, but those having a wavelength in the range of 200 to 500 nm are preferable. As a method of irradiating actinic radiation in a pattern, a method of irradiating actinic radiation through a photomask having openings of a desired pattern is generally used. Good. After exposure, a non-irradiated portion of the coating film is dissolved and removed with a developer to obtain a relief pattern. In the present invention, an alkaline developer or an alkaline aqueous solution is used as the developer.

The alkaline developer is a developer obtained by dissolving a basic compound in a solvent containing 50% by weight or more of an organic solvent. Examples of the organic solvent include aprotic polar solvents such as N-methyl-2-pyrrolidone, N-acetylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, and γ-butyrolactone. . Further, a general organic solvent such as alcohols such as methanol and ethanol; aromatic hydrocarbon compounds such as toluene and xylene; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran and dioxazine; and water are mixed and used. be able to.

The alkaline aqueous solution is a developer obtained by dissolving a basic compound in a solvent containing 51% by weight or more of water. Solvent components other than water include, for example, aprotic polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, γ-butyrolactone; methanol,
Alcohols such as ethanol and isopropyl alcohol; aromatic hydrocarbon compounds such as toluene and xylene; ketones such as acetone, methyl ethyl ketone and cyclopentanone; esters such as methyl acetate and methyl lactate; ethers such as tetrahydrofuran and dioxazine; Diols such as ethylene glycol and diethylene glycol; cellosolves such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether; and the like.

Examples of the basic compound (alkali) include hydroxides, carbonates, bicarbonates, silicates, phosphates, pyrophosphates, acetates and amine salts of alkali metals and quaternary ammoniums. Is used. Specific examples of these include sodium hydroxide, lithium hydroxide, potassium hydroxide, ammonium hydroxide, trimethylbenzylammonium hydroxide, tetramethylammonium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogencarbonate, sodium silicate, phosphorus Sodium salt, sodium pyrophosphate, sodium acetate, monoethanolamine, diethanolamine, triethanolamine, choline and the like, but are not limited thereto.

The proportion of the basic compound used is usually 0.001 to 50 parts by weight, preferably 0.05 to 30 parts by weight, based on 100 parts by weight of the solvent. If the use ratio is too small, the developability is reduced, and if it is too large, the basic compound is not completely dissolved and becomes a non-uniform solution, or the alkali concentration is too high, and the solubility in polyamic acid is too strong. The surface of the non-exposed area may be roughened. The basic compound has a pH of the developing solution of usually 10.0 or more, preferably 1 or more.
It is desirable to use them at a ratio that falls within the range of 1.0 to 13.5. If the pH of the developing solution is too low, the developing speed tends to decrease.If the pH is too high, the solubility in polyamic acid is too strong. , A difference in solubility of the compound becomes small, and it becomes difficult to form a pattern having a good shape.

As the developer, an alkali developer and an aqueous alkali solution may be used alone or as a mixture. When the alkali developer and the aqueous alkali solution are mixed and used, the amount of the organic solvent used is usually 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight, based on 100 parts by weight of water. As the developer, it is preferable to use an inexpensive alkaline aqueous solution that is safer for the human body. Thus, in the present invention, it is preferable to use an alkaline aqueous solution as the developer. It is preferable that the alkaline aqueous solution does not contain an organic solvent. Even when an organic solvent is used in combination, it is preferable that the ratio is small in order to solve the above-mentioned problems associated with the use of the organic solvent.

As the developing method, various methods such as spraying, paddle, dipping, and ultrasonic waves can be adopted. It is desirable to select paddle development or ultrasonic immersion development according to the degree of ease of alkali development of the photosensitive polyimide resin. The developing speed is also affected by the temperature of the developer. Therefore, it is desirable to check various conditions such as the pH and temperature of the developing solution or the developing method in advance and to set the optimum conditions. The relief pattern formed by the development is washed with a rinsing liquid to remove the developing liquid. In the present invention, an acidic rinsing liquid as described above or an acidic rinsing liquid containing an aprotic polar solvent is used. The cleaning process is usually performed by immersing the developed substrate in a rinse solution for a predetermined time. After performing the washing treatment with the acidic rinsing solution, water washing (water rinsing) or the like may be performed, if desired, in order to remove the remaining acidic compound. However, by selecting the type and concentration of the acidic compound, it is not always necessary to perform a washing treatment with water, an organic solvent, a mixed solvent, or the like after the washing treatment with the rinse solution of the present invention.

In the case where the relief pattern is removed after performing the etching process after the cleaning process, the polyimide treatment by heat treatment is not necessary. The effect of the present invention is greatly exhibited when the polyamide acid film is converted into a polyimide film by heat treatment after the cleaning treatment. That is, after the cleaning treatment (rinsing), a heat treatment is performed to form an imide ring, and the polyamide acid is converted into a polyimide, whereby a final relief pattern (polyimide film) having high heat resistance can be obtained.
On this polyimide film, for example, a metal thin film such as a chromium sputtered film is formed, and a multilayer wiring can be further formed. Polyimide films are used not only for semiconductor device manufacturing-related applications, but also, for example, for LSI buffer coat films, passivation films, interlayer insulation films for multilayer circuits, cover coat films for flexible copper clad boards, various metal core substrates and ceramic substrates. It can also be used as a cover film, a solder resist film, a liquid crystal alignment film, and the like.

<Photosensitive Polyimide Resin> As described above, the photosensitive polyimide resin used in the present invention is not particularly limited as long as it is a photosensitive polyimide resin (photosensitive resin composition) that can be alkali-developed. Among them, it is preferable to use a photosensitive resin composition containing (A) a polyamic acid having an actinic radiation functional group, (B) a photosensitive auxiliary having a photopolymerizable functional group, and (C) a photopolymerization initiator. . However,
In order to obtain a polyamic acid which can be developed with an alkali, particularly an aqueous alkali solution, it is desirable to use a polyamic acid adjusted to contain a carboxyl group capable of forming a salt with an alkali in a specific range. Hereinafter, the photosensitive resin composition containing a polyamic acid having such a preferable actinic radiation functional group will be described in detail.

(A) Polyamic acid having an actinic radiation functional group The photosensitive polyimide resin used in the present invention is a polyamic acid having an actinic radiation functional group as a polyamic acid having the formula (1) in its main chain.

[0037]

Embedded image (Wherein, R ¹ is a tetravalent organic group, and R ² is a divalent organic group.)
Equation (2)

[0038]

Embedded image (Wherein X is a single bond, -O-, -CO-, -COO
-, - OCO -, - OCOO -, - COCH 2 O -, -
S -, - SO -, - SO ₂ -, or -SO ₂ are ^{O-, R 3, R 4,} R 5, R 6, and R ⁷ are photopolymerizable carbon - carbon double bonds A substituent, m is 0 or 1, and n is an integer in the range of 1-3. Groups Z ¹ represented by), and (3)

[0039]

Embedded image (Wherein, R ³ , R ⁴ , R ⁵ , R ⁶ , and R ⁷ are substituents having a photopolymerizable carbon-carbon double bond, and m is 0
Or 1. Has at least one actinic radiation functional group selected from the group consisting of groups Z ² at both terminals,
When the repeating unit represented by the formula (1) is defined as a unit molecular weight, it is possible to use a polyamic acid having a unit molecular weight value per one carboxyl group (unit molecular weight / -COOH) in the range of 200 to 300. preferable. As such a polyamic acid, a compound of the formula (4) having actinic radiation functional groups Z ¹ represented by the formula (2) at both terminals

[0040]

Embedded image [Wherein, R ¹ is a tetravalent organic group, R ² is a divalent organic group, k is an integer in the range of 5 to 10,000, and Z ¹ is a group represented by the formula (2) Is an actinic radiation functional group represented by Polyamic acids represented by] (A1), and (3) having the formula actinic functional group Z ² represented at both ends (5)

[0041]

Embedded image [Wherein, R ¹ is a tetravalent organic group, R ² is a divalent organic group, k is an integer in the range of 5 to 10,000, and Z ² is a group represented by the formula (3) Is an actinic radiation functional group represented by And a polyamic acid (A2) represented by the following formula:

By adjusting the value of the unit molecular weight per carboxyl group (unit molecular weight / -COOH) of the polyamic acid having actinic radiation functional groups at both ends to fall within the range of 200 to 300, the alkali developing solution And a polyamic acid having an appropriate solubility in an alkaline aqueous solution and capable of forming a good pattern. Polyamic acid (A1) is usually a diamine compound and p-aminobenzoic acid [tris (methacryloyl) pentaerythritol]
It can be obtained by adding tetracarboxylic acid or an acid anhydride thereof to a mixture with an aminobenzene such as an ester, and subjecting the mixture to a condensation reaction by a conventional method. According to this method, a high molecular weight polyamic acid can be stably obtained. The polyamic acid (A2) is obtained by adding a trimellitic acid derivative such as trimellitic anhydride [tris (methacryloyl) pentaerythritol] ester and a tetracarboxylic acid or an anhydride thereof to a diamine compound and subjecting the mixture to a condensation reaction by a conventional method. Obtainable. The polyamic acid (A1) can also be obtained by adding a tetracarboxylic acid or an anhydride thereof to a mixture of a diamine compound and a trimellitic acid derivative and subjecting the mixture to a condensation reaction by a conventional method. According to these methods, a high molecular weight polymer can be obtained stably.

Diamine compound The diamine compound used in the present invention includes, for example,
2,2'-di (p-aminophenyl) -6,6'-bibenzoxazole, 2,2'-di (p-aminophenyl) -5,5'-bibenzoxazole, m-phenylenediamine, 1 -Isopropyl-2,4-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenylpropane, 4,4'-diaminodiphenylethane, 3,
3'-diaminodiphenylethane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 3,
3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether,
3,3'-diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene, benzidine,
4 "-diamino-p-terphenyl, 3,3" -diamino-p-terphenyl, bis (p-aminocyclohexyl) methene, bis (p-β-amino-t-butylphenyl) ether, bis (p- β-methyl-δ-aminopentyl) benzene, p-bis (2-methyl-4-aminopentyl) benzene, p-bis (1,1-dimethyl-5-
Aminopentyl) benzene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,4-bis (β-
Aromatics such as amino-t-butyl) toluene, 2,4-diaminotoluene, m-xylene-2,5-diamine, p-xylene-2,5-diamine, m-xylylenediamine and p-xylylenediamine Diamines; 2,6-diaminopyridine, 2,5-diaminopyridine, 2,5-
Heterocyclic diamines such as diamino-1,3,4-oxadiazole; alicyclic diamines such as 1,4-diaminocyclohexane; piperazine, methylenediamine, ethylenediamine, propylenediamine, 2,2-dimethylpropylenediamine; Tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 2,5-
Dimethylhexamethylenediamine, 3-methoxyhexamethylenediamine, heptamethylenediamine, 2,5-
Dimethylheptamethylenediamine, 3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine, octamethylenediamine, nonamethylenediamine, 5-methylnonamethylenediamine, 2,5-dimethylnonamethylenediamine, decamethylenediamine, 1 ,
10-diamino-1,10-dimethyldecane, 2,11
Aliphatic diamines such as diaminododecane, 1,12-diaminooctadecane, 2,12-diaminooctadecane and 2,17-diaminoicosane; diaminosiloxane, 2,6-diamino-4-carboxylic benzene, 3,3 ′ -Diamino-4,4'-dicarboxylic benzidine and the like.

These diamine compounds can be used alone or in combination of two or more. Among these, 4,4'-diaminodiphenyl ether, 4,4'-diaminobenzanilide, 1,4
-Bis (4-aminophenoxy) benzene is particularly preferable since a polymer having appropriate solubility in an alkali developer and high heat resistance can be obtained. Therefore, R ² in the formula (1) is a divalent organic group derived from a diamine compound such as an aromatic diamine, a heterocyclic diamine, an alicyclic diamine, or an aliphatic diamine.

Tetracarboxylic acid or its anhydride The tetracarboxylic acid or its anhydride used in the present invention includes, for example, pyromellitic dianhydride, 3,3
3 ', 4,4'-benzophenonetetracarboxylic dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 2,2', 3,3'-benzophenonetetracarboxylic dianhydride , 2,3,3 ', 4'-benzophenonetetracarboxylic dianhydride, naphthalene-2,3,
6,7-tetracarboxylic dianhydride, naphthalene-1,
2,5,6-tetracarboxylic dianhydride, naphthalene-
1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,2,5,8-tetracarboxylic dianhydride, naphthalene-1,2,6,7-tetracarboxylic dianhydride,
4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5 , 6,7-
Hexahydronaphthalene-2,3,6,7-tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,
4,5,8-tetracarboxylic dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-
1,4,5,8-tetracarboxylic dianhydride, 1,4
5,8-tetrachloronaphthalene-2,3,6,7-tetracarboxylic dianhydride, 3,3 ', 4,4'-diphenyltetracarboxylic dianhydride, 2,2', 3,3 ' −
Diphenyltetracarboxylic dianhydride, 2,3,3 ',
4'-diphenyltetracarboxylic dianhydride, 2,
3 ", 4,4" -p-terphenyltetracarboxylic dianhydride, 2,2 ", 3,3" -p-terphenyltetracarboxylic dianhydride, 2,3,3 ", 4"- p-terphenyltetracarboxylic dianhydride, 2,2-bis (2,
3-dicarboxyphenyl) -propane dianhydride, 2,
2-bis (3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl)
Ether dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) sulfone dianhydride, Bis (3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3
-Dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride,
Perylene-2,3,8,9-tetracarboxylic dianhydride, perylene-3,4,9,10-tetracarboxylic dianhydride, perylene-4,5,10,11-tetracarboxylic dianhydride , Perylene-5,6,11,12-tetracarboxylic dianhydride, phenanthrene-1,2,7,8
-Tetracarboxylic dianhydride, phenanthrene-1,
Aromatic tetracarboxylic dianhydrides such as 2,6,7-tetracarboxylic dianhydride and phenanthrene-1,2,9,10-tetracarboxylic dianhydride and their water additives;
Cyclopentane-1,2,3,4-tetracarboxylic dianhydride, cyclobutanetetracarboxylic dianhydride, bicyclo [2,2,2] oct-7-en-2-exo, 3
-Exo, 5-exo, 6-exotetracarboxylic acid 2,3: 5,6-dianhydride, bicyclo [2,2,1] heptane-2-exo, 3-exo, 5-exo, 6-exo Alicyclic acid dianhydrides such as tetracarboxylic acid 2,3: 5,6-dianhydride; pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5 -Tetracarboxylic dianhydride, thiophene-2,3,4,5
-Heterocyclic derivative acid dianhydride such as tetracarboxylic dianhydride.

These can be used alone or in combination of two or more. Among these, pyromellitic dianhydride, 3,3 ', 4,4'-
Benzophenonetetracarboxylic dianhydride and combinations thereof are particularly preferred for achieving good low thermal expansion, crack resistance, resolution and the like. Accordingly, R ¹ in the formula (1) is derived from a tetracarboxylic acid such as an aromatic tetracarboxylic dianhydride and a water additive thereof, an alicyclic acid anhydride, and a heterocyclic derivative acid anhydride or an acid anhydride thereof. It is a derived tetravalent organic group.

[0047] In amino benzene present invention can react with the carboxyl groups of tetracarboxylic acid or anhydride thereof, as a compound which gives a substituent Z ¹ of the formula (2), using the amino benzenes . Examples of such aminobenzenes include a compound represented by the following formula (6).

[0048]

Embedded image [Wherein, X is a single bond, -O-, -CO-, -COO
-, - OCO -, - OCOO -, - COCH 2 O -, -
S -, - SO -, - SO ₂ -, or -SO ₂ are ^{O-, R 3, R 4,} R 5, R 6, and R ⁷ are photopolymerizable carbon - carbon double bonds A substituent, m is 0 or 1, and n is an integer in the range of 1-3. ]

Representative examples of the photopolymerizable substituent having a carbon-carbon double bond include an acryloyloxymethylene group and a methacryloyloxymethylene group. , Butenyl, pentynyl, hexynyl, 2
An alkenyl group having 2 to 6 carbon atoms such as -ethylbutenyl group or a substituted product thereof. Specific examples of the substituent capable of bonding to an alkenyl group having 2 to 6 carbon atoms include a halogen atom, a phenyl group, an alkyl group having 1 to 4 carbon atoms, and a carbon atom having 1 carbon atom.
And 4 alkoxy groups. In equation (6), X
Is —COO—, the aminobenzenes are aminobenzenecarboxylic acid esters represented by the following formula (7).

[0050]

Embedded image [Wherein, R ^{3 to} R ⁷ , m and n are the same as described above. ]
Aminobenzenes such as such aminobenzenecarboxylic acid esters can be produced according to the method described in JP-A-8-82931. Therefore, the content of the publication is adopted in the specification of the present application. The aminobenzenecarboxylic acid ester has a structure represented by the formula (7), and the benzene ring has an amino group and 1 to
Although three carboxylic ester residues are bonded, the bonding site of the carboxylic ester residue to the amino group is o
Any of-, m- and p- may be used.

Specific examples of the aminobenzenecarboxylic acid ester include o-aminobenzoic acid [tris (methacryloyl) pentaerythritol] ester, o-aminobenzoic acid [tris (acryloyl) pentaerythritol] ester, m-aminobenzoic acid [ Tris (methacryloyl) pentaerythritol] ester, m-aminobenzoic acid [tris (acryloyl) pentaerythritol] ester, p-aminobenzoic acid [tris (methacryloyl) pentaerythritol] ester, p-aminobenzoic acid [tris (acryloyl) penta] Erythritol] ester, 5-amino-isophthalic acid [tris (methacryloyl) pentaerythritol] diester, 5
-Amino-isophthalic acid [tris (acryloyl) pentaerythritol] diester, o-aminobenzoic acid [pentakis (methacryloyl) dipentaerythritol] ester, o-aminobenzoic acid [pentakis (acryloyl) dipentaerythritol] ester, m-amino Benzoic acid [pentakis (methacryloyl) dipentaerythritol] ester, m-aminobenzoic acid [pentakis (acryloyl) dipentaerythritol] ester, p-aminobenzoic acid [pentakis (methacryloyl) dipentaerythritol] ester, p-aminobenzoic acid [Pentakis (acryloyl) dipentaerythritol] ester and the like. Among these, p-aminobenzoic acid [tris (methacryloyl) pentaerythritol] ester is a synthesis cost,
It is excellent in operability, high sensitivity, high resolution and the like, and is particularly preferable.

In order to synthesize a polyamic acid (A1) having an actinic radiation functional group Z ¹ of the formula (2) introduced at both ends, a tetracarboxylic acid or its anhydride is added to a mixture of a diamine compound and an aminobenzene. In addition, a condensation reaction is performed by a conventional method. More specifically, to synthesize a polyamic acid obtained by introducing a chemical ray functional group Z ¹ at both ends, typically 0.850 to 0.990 mol relative to the tetracarboxylic acid or its anhydride to 1 mole of the diamine compound , Preferably 0.900
It is used in a ratio of 0.970 mol, and aminobenzenes are usually used in an amount of 0.400 to 0.1 mol per mol of the diamine compound.
020 mol, preferably 0.110-0.040 mol,
More preferably, it is used in a ratio of 0.100 to 0.050 mol, and further, tetracarboxylic acid or its anhydride 1
The total amount of the diamine compound and the aminobenzenes is usually 1.100 to 0.900 mol, preferably 1.100 to 0.950 mol, more preferably 1.0 to 1.0 mol.
It is used in a proportion of 60 to 0.990 mol. The condensation reaction is
The components may be reacted in a polar organic solvent such as dimethylacetamide according to a conventional method for synthesizing a polyamic acid. The reaction conditions are, for example, 0.5 to 10 under ice cooling.
Time, preferably 1-5 hours, then 1-5 at room temperature
The reaction may be performed for 0 hour, preferably 5 to 30 hours. However, the polyamic acid of the present invention (A
1) is not limited to a specific synthesis method.

Trimellitic acid derivative In the present invention, a trimellitic acid derivative of the following formula (8) is used as a compound that gives a substituent Z ² represented by the formula (3) to both ends of a polyamic acid.

[0054]

Embedded image [Wherein, R ³ , R ⁴ , R ⁵ , R ⁶ , and R ⁷ are substituents having a photopolymerizable carbon-carbon double bond, and m is 0
Or 1. ]

Representative examples of the photopolymerizable substituent having a carbon-carbon double bond include an acryloyloxymethylene group and a methacryloyloxymethylene group, and in addition, a vinyl group, a propenyl group, and an isopropenyl group. , Butenyl, pentynyl, hexynyl, 2
An alkenyl group having 2 to 6 carbon atoms such as -ethylbutenyl group or a substituted product thereof. Specific examples of the substituent capable of bonding to an alkenyl group having 2 to 6 carbon atoms include a halogen atom, a phenyl group, an alkyl group having 1 to 4 carbon atoms, and a carbon atom having 1 carbon atom.
And 4 alkoxy groups. Such a trimellitic acid derivative can be synthesized according to the method described in JP-A-8-95247. Therefore, the synthesis method described in this publication is incorporated herein by reference. A representative trimellitic acid derivative used in the present invention is a compound represented by the formula (9).

[0056]

Embedded image [In the formula, R is a hydrogen atom or a lower alkyl group having 1 to 5 carbon atoms. Examples of the trimellitic acid derivative include trimellitic anhydride [tris (acryloyl) pentaerythritol] ester [in the formula (9), when R = H], trimellitic anhydride [tris (methacryloyl) pentaerythritol] Esters (in the case of R = methyl group in the formula (9)) and the like are excellent in terms of synthesis cost, operability, high sensitivity, high resolution and the like, and are particularly preferable.

To synthesize a polyamic acid (A2) having an actinic radiation functional group Z ² of the formula (3) introduced at both ends, a trimellitic acid derivative and a tetracarboxylic acid or an anhydride thereof are added to a diamine compound. The condensation reaction is carried out by a conventional method. Alternatively, a tetracarboxylic acid or an anhydride thereof may be added to a mixture of a diamine compound and a trimellitic acid derivative, and a condensation reaction may be performed by a conventional method. More specifically, in order to synthesize a polyamic acid having actinic ray functional groups introduced at both ends, tetracarboxylic acid or an anhydride thereof is usually added in an amount of 0.850 to 0.990 per 1 mol of the diamine compound.
Mole, preferably 0.900 to 0.970 mole, and (2) 1 mole of tetracarboxylic acid or its anhydride, the trimellitic acid derivative is usually used in an amount of 0.400 to 0.900 mole.
0.020 mol, preferably 0.110 to 0.040 mol, more preferably 0.100 to 0.050 mol, and further (3) 1 mol of diamine compound, tetracarboxylic acid or The anhydride and trimellitic acid derivative are used in a total amount of usually 1.100 to 0.900 mol, preferably 1.100 to 0.990 mol, more preferably 1.060 to 1.020 mol. I do.
In the condensation reaction, each component may be reacted in a polar organic solvent such as dimethylacetamide according to a conventional method for synthesizing a polyamic acid. The reaction conditions include, for example, a method of reacting under ice cooling for 0.5 to 10 hours, preferably 1 to 5 hours, and then at room temperature for 1 to 50 hours, preferably 5 to 30 hours. However, the polyamic acid (A2) used in the present invention is not limited to a specific synthesis method.

Polyamic acid The polyamic acid preferably used in the present invention has a repeating unit represented by the formula (1) in the main chain thereof and has a formula (2)
Is a polyamic acid having at least one actinic ray functional group selected from the group consisting of a group Z ¹ represented by the formula ( ¹ ) and a group Z ² represented by the formula (3) at both terminals. This polyamic acid defines a repeating unit represented by the formula (1) as a unit molecular weight,
It is desirable that the value of the unit molecular weight per carboxyl group (ratio of unit molecular weight / -COOH) be in the range of 200 to 300 for alkali development. If the value of the unit molecular weight per carboxyl group is too small, the polyamic acid becomes extremely soluble in an alkali developing solution or a developing solution composed of an alkaline aqueous solution, so that pattern formation is difficult or impossible in some cases. If this value is too large, the polyamic acid is difficult to dissolve in an alkali developer or a developer composed of an alkaline aqueous solution, or becomes insoluble in some cases, making it impossible to form a pattern. From the viewpoint of the balance between the developing property with respect to a developing solution comprising an alkali developing solution or an aqueous alkali solution and the film properties, the value of the unit molecular weight per carboxyl group is preferably from 205 to 29.
5, more preferably within the range of 230 to 280. In order to adjust the value of the unit molecular weight per carboxyl group of the polyamic acid within this range, the type and combination of each monomer used are selected.

(B) Photosensitizer Having Photopolymerizable Functional Group The photosensitizer usable in the present invention is not particularly limited as long as it is generally known as a photocurable monomer. Representative examples of the photosensitizer include (meth) acrylic acid compounds such as pentaerythritol triacrylate. As the acrylic acid compound, for example, acrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-
Butyl acrylate, isobutyl acrylate, cyclohexyl acrylate, benzyl acrylate, carbitol acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, butylene glycol monoacrylate, N, N-dimethylaminoethyl acrylate, N,
N-diethylaminoethyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, pentaerythritol monoacrylate, trimethylolpropane monoacrylate, allyl acrylate, 1,
3-propylene glycol diacrylate, 1,4-butylene glycol diacrylate, 1,6-hexane glycol diacrylate, neopentyl glycol diacrylate, dipropylene glycol diacrylate,
2,2-bis- (4-acryloxydiethoxyphenyl) propane, 2,2-bis- (4-acryloxypropylxyphenyl) propane, trimethylolpropane diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate Pentaerythritol triacrylate, triacryl formal, tetramethylol methane tetraacrylate, acrylate of tris (2-hydroxyethyl) isocyanuric acid, formula (10)

[0060]

Embedded image (Where b represents an integer of 1 to 30), a compound represented by the formula (11):

[0061]

Embedded image (Wherein c and d represent an integer such that c + d = 2 to 30), a compound represented by the formula (12):

[0062]

Embedded image A compound represented by the formula (13):

[0063]

Embedded image And the like.

Examples of the methacrylic acid compound include, for example,
Methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, octyl methacrylate, ethylhexyl methacrylate, methoxyethyl methacrylate, ethoxyethyl methacrylate, butoxyethyl methacrylate, hydroxyethyl methacrylate, hydroxy Propyl methacrylate, hydroxybutyl methacrylate, hydroxypentyl methacrylate, N, N-dimethylamino methacrylate, N, N-diethylamino methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, methacryloxypropyl trimethoxysila , Allyl methacrylate, trimethylolpropane monomethacrylate, pentaerythritol monomethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, 2,2-bis- (4-methacryloxy Diethoxyphenyl) propane, trimethylolpropane dimethacrylate, pentaerythritol dimethacrylate, trimethylolpropane triacrylate, pentaerythritol trimethacrylate, tetramethylolmethanetetramethacrylate, tris (2-hydroxyethyl)
Methacrylic acid ester of isocyanuric acid, formula (14)

[0065]

Embedded image (Wherein e represents an integer of 1 to 30), a compound represented by the formula (15):

[0066]

Embedded image (Where f and g represent integers satisfying f + g = 1 to 30), a compound represented by the formula (16):

[0067]

Embedded image A compound represented by the formula (17):

[0068]

Embedded image And the like.

These compounds can be used alone or in combination of two or more. Among these, pentaerythritol triacrylate and the compound represented by the formula (10) (b = 3) are particularly preferable. The amount of the photosensitizer used is not particularly limited as long as it is compatible with the polyamic acid.However, when the amount used is extremely large, it is difficult to decompose and remove the polyamic acid during the heat treatment of the polyamic acid by polyimide. There is a problem that the residual stress is increased and the semiconductor element substrate is likely to be deformed such as warp. Therefore, the photosensitizer is used in an amount of usually 10 to 40 parts by weight, preferably 15 to 35 parts by weight, more preferably 20 to 30 parts by weight, per 100 parts by weight of the polyamic acid (A).
It is desirable to use them in parts by weight.

(C) Photopolymerization Initiator The photopolymerization initiator used in the present invention includes, for example, Michler's ketone, benzoin, 2-methylbenzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, t-butylanthraquinone, 1,
2-benzo-9,10-anthraquinone, anthraquinone, methylanthraquinone, 4,4'-bis- (diethylamino) benzophenone, acetophenone, benzophenone, thioxanthone, 1,5-acenaphthene, 2,
2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-
[4- (methylthio) phenyl] -2-morpholino-
1-propanone, diacetylbenzyl, benzyldimethylketal, benzyldiethylketal, diphenyldisulfide, anthracene, phenanthrenequinone, riboflavin tetrabutyrate, acrylic orange, erythrosine, phenanthrenequinone, 2-isopropylthioxanthone, 2,6-bis (P-diethylaminobenzylidene) -4-methyl-4-azacyclohexanone,
6-bis (p-dimethylaminobenzylidene) -cyclopentanone, 2,6-bis (p-diethylaminobenzylidene) -4-phenylcyclohexanone, formula (18)

[0071]

Embedded image An aminostyryl ketone represented by the formula (19)

[0072]

Embedded image (Wherein, R ^11, R ^12, and R ¹³ each independently represent a hydrogen atom, a hydroxyl group, containing 1-5 alkyl groups carbon atoms, a dialkylamino group, an alkoxy group or an acyloxy group,, R ¹⁴ Is an aromatic carbocyclic or heterocyclic ring having 5 to 20 ring atoms.) A 3-ketocoumarin compound represented by the formula (20):

[0073]

Embedded image (Wherein, R ²⁰ and R ²¹ are each independently a hydrogen atom,
It is an alkyl group having 1 to 5 carbon atoms, a dialkylamino group, an alkoxy group, or an acyloxy group. ), N-phenylglycine, N-phenyldiethanolamine, 3,3 ', 4,4'tetra (t-butylperoxycarbonyl) benzophenone, and the like. The amount of the photopolymerization initiator to be used is not particularly limited, but is usually 0.01 to 10 parts by weight, preferably 0.1 to 100 parts by weight of the polyamic acid (A).
To 5 parts by weight, more preferably 1 to 5 parts by weight.

(D) Solvent The photosensitive polyimide resin (photosensitive resin composition) is used after being uniformly dissolved or dispersed in a solvent. As the solvent,
For example, polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, tetramethylurea, hexamethylphosphoric triamide, and γ-butyrolactone are exemplified. In addition to these polar solvents, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, and diethyl malonate; diethyl ether, ethylene glycol dimethyl ether; Diethylene glycol dimethyl ether,
Ethers such as tetrahydrofuran; dichloromethane;
Halogenated hydrocarbons such as 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene; and hydrocarbons such as hexane, heptane, octane, benzene, toluene, xylene and the like are also used. can do. These solvents can be used alone or in combination of two or more. Among these, N, N-dimethylacetamide and N-methyl-2-pyrrolidone are particularly preferred. The amount of the solvent used is generally an amount sufficient to dissolve each component uniformly. The amount of the solvent to be used varies depending on the type of the solvent and the type of the polyamic acid.
It is within the range of 20 to 20 times, more preferably 6 to 10 times.

(E) Other Additives In the composition of the present invention, various additives such as an adhesion aid, a leveling agent, and a polymerization inhibitor can be further used, if necessary. Among various additives, 1H-tetrazole,
5,5'-bis-1H-tetrazole and derivatives thereof prevent corrosion to copper and copper alloys, and
The adhesion of the polyimide film to the substrate can be improved, and the photosensitive film can be prevented from remaining. 1H-tetrazole and its derivative are represented by the following formula (21)

[0076]

Embedded image Can be represented by 5,5'-bis-1H-tetrazole and its derivative are represented by the following formula (22)

[0077]

Embedded image It is a compound represented by these. Definition of R ₁ : In formulas (21) and (22), R 1
₁ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an allyl group having 3 to 10 carbon atoms,
A cyclic aliphatic group having 3 to 6 carbon atoms, a phenyl group, the following formula (2
3)

[0078]

Embedded image [Wherein, n is an integer of 1 to 3, and X is
10 alkyl groups, C1-10 alkoxy groups,-
NR'R "(R'R" are independently a hydrogen atom, a methyl group, an ethyl group, an acetyl group, an ethylcarbonyl _{group), - COOH, -COOCH 3,} -NO 2, -OH,
—SH or —SCH ₃ . Or a substituted phenyl group represented by the formula (24):

[0079]

Embedded image [Wherein, m is an integer of 1 to 10, and Y is -COO
H, -NR'R "(R'R" is independently a hydrogen atom, a methyl group, an ethyl group, an acetyl group, an ethylcarbonyl group), a phenyl group, or a substituent represented by the formula (23). It is a phenyl group. And a substituted methyl group represented by the formula:

Among these substituents, specific examples of preferred substituents for R ₁ include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group, and a t-butyl group. Butyl group, pentyl group,
3-methyl-1-butyl group, hexyl group, 4-methyl-
An alkyl group having 1 to 6 carbon atoms such as a 1-pentyl group; a cyclic aliphatic group having 3 to 6 carbon atoms such as a cyclopropyl group, a cyclopentyl group, a 2-methylcyclopentyl group, a cyclohexyl group; a phenyl group; 3) wherein n is 1 or 2 and X is an alkyl group having 1 to 6 carbon atoms, an amino group, a methylamino group, an acetamido group, -SH, -OH, for example, A substituted phenyl group such as a methylphenyl group, a dimethylphenyl group, a butylphenyl group, a t-butylphenyl group, an aminophenyl group, an aminomethylphenyl group, an acetamidophenyl group, a mercaptophenyl group, and a hydroxyphenyl group; M) is 1 or 2, and Y is a phenyl group, an amino group, a methylamino group, Methylamino group, acetamido group, for example, benzyl group, aralkyl group such as phenethyl group, aminomethyl group, aminoethyl group, methylaminomethyl group, dimethylaminomethyl group, (substituted) amino group such as acetylaminomethyl group Methyl group; and the like.

Definition of R ₂ : In the formula (21), R ₂ is
Hydrogen atom, hydroxyl group, cyano group, alkyl group having 1 to 10 carbon atoms, alkenyl group having 2 to 10 carbon atoms, 2 to 10 carbon atoms
An alkynyl group, a cyclic aliphatic group having 3 to 6 carbon atoms, a phenyl group, a substituted phenyl group, -OR ₃ (where R ₃ is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, An alkynyl group having 2 to 10 carbon atoms, a phenyl group, or a substituted phenyl group represented by the above formula (23)), the following formula (25)

[0082]

Embedded image Wherein k is an integer in the range of 1 to 10, and Z is
Halogen atom, amino group, -NR'R "(R 'and R"
Is independently a hydrogen atom, a methyl group, an ethyl group, an acetyl group or an ethylcarbonyl group), a phenyl group, a substituted phenyl group represented by the above formula (23), -SH, -SR ₄
(Where R ₄ is an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a phenyl group, or a substituted phenyl group represented by the above formula (23)) _{), - C (NH 2)} H- (CH 2) n-CH
₃ (where n = 1 to 5) or —C (NHCH ₃ ) H
- a _{(CH 2) n-CH 3} ( provided that, n = 0~5). Or a substituted methyl group represented by the following formula (26):

[0083]

Embedded image [Wherein A is -CO-, -NHCO-, -C (= N-
OH) -, - CH (OH ), - CH (NH 2) -, - C
H (Cl) and —CH (Br) —, wherein R ₅ is an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, a cyclic aliphatic group having 3 to 6 carbon atoms, a phenyl group, A substituted phenyl group represented by the above formula (23), a substituted methyl group represented by the above formula (25), or the following formula (27)

[0084]

Embedded image [Wherein X is an alkyl group having 1 to 10 carbon atoms, 1 carbon atom
To 10 alkoxy groups, amino groups, -NR'R "(R '
R "is independently a hydrogen atom, a methyl group, an ethyl group, an acetyl group or an ethylcarbonyl group), -COOH,-
_{COOCH 3, -NO 2, -OH,} -SH or -SC,
H ₃ . ] It is a group represented by these. ] The group represented by this.

Preferred examples of R ₂ include a hydrogen atom; a cyano group; a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group;
C1-C6 alkyl group such as t-butyl group, pentyl group, 3-methyl-1-butyl group, hexyl group, 4-methyl-1-pentyl group; cyclopropyl group, cyclopentyl group, 2-methylcyclopentyl A cycloaliphatic group having 3 to 6 carbon atoms, such as a cyclohexyl group; a phenyl group;
A substituted phenyl group having an alkyl group having 1 to 6 carbon atoms such as a methylphenyl group, an ethylphenyl group, a propylphenyl group, a butylphenyl group, a pentylphenyl group, and a hexylphenyl group; an aminophenyl group, a methylaminophenyl group and an acetamidophenyl A (substituted) aminophenyl group such as a group; k is 1 or 2 among the substituted methyl groups represented by the formula (25), and Z is a phenyl group, an amino group, a methylamino group, a dimethylamino group, or an acetamido group For example, aralkyl groups such as benzyl group and phenethyl group, (substituted) aminomethyl groups such as aminomethyl group, aminoethyl group, methylaminomethyl group, dimethylaminomethyl group and acetylaminomethyl group; and the like. Can be

1H-tetrazole, 5,5'-bis-1
Preferred specific examples of H-tetrazole and derivatives thereof include unsubstituted 1H-tetrazole;
1H-tetrazole; 1-substituted-1H-tetrazole such as 1-methyl-1H-tetrazole; 1-phenyl-5
-Substituted-5-substituted-1H-tetrazole such as -mercapto-1H-tetrazole;
Among them, 1H-tetrazole in which R ₁ = H and 5-substituted-1H-tetrazole are particularly preferable.

The 1H-tetrazole, 5,
5'-bis -1H- tetrazole, derivatives thereof (hereinafter, abbreviated as "1H- tetrazoles") is, R ₁ represents a particularly high effect is that of a hydrogen atom. The reason is that
When a hydrogen atom is bonded to the 1-position N site of 1H-tetrazole, its hydrogen ions (protons) in a solution are as acidic as acetic acid and can easily form a salt with a metal or a base. it can. Thus, 1H-tetrazoles react with copper and copper alloys to form copper salts. This copper salt is stable against oxidation and suppresses release of copper ions. In addition, 1H-tetrazole suppresses a reaction between a carboxyl group in polyamic acid and copper or a copper alloy,
It is considered that the formation of copper carboxylate is suppressed. On the other hand, R
It is considered that 1H-tetrazoles in which ₁ is other than a hydrogen atom exhibit basicity and have an effect of neutralizing a carboxyl group in polyamic acid rather than an effect on copper. However, even if such a tetrazole is used, the effect of improving the residual film ratio is exhibited, though the effect is slightly lower.

1H-tetrazole is usually used in an amount of 0.0
It is used in an amount of 5 to 20 parts by weight, preferably 0.1 to 5 parts by weight, more preferably 0.3 to 3.0 parts by weight.
If the compounding ratio is too small, the effect of addition is small, and conversely,
If it is excessive, the effect is saturated. 1H-tetrazoles are usually added to a polyamic acid solution to form a resin composition (solution), and the obtained composition is used for application to a substrate or the like to form a film.

[0089]

The present invention will be more specifically described below with reference to Synthesis Examples, Reference Examples, Examples and Comparative Examples. [Synthesis Example 1] <Preparation of photosensitive polyimide resin> In a reactor equipped with a stirrer and a dry gas introduction tube, 45.9 g (0.202 mol) of 4,4'-diaminobenzanilide and 811 g of dimethylacetamide were charged. Stir at 50 ° C. to dissolve. 22.9 g of pyromellitic dianhydride was added to this solution.
(0.105 mol), 33.8 g of 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (0.10 mol)
5 mol), and reacted at a reaction temperature of 50 ° C. for 3 hours. Then, after cooling to 10 ° C. or less, 9.8 g (0.045 mol) of pyromellitic dianhydride, 3,3 ′, 4,
4'-benzophenonetetracarboxylic dianhydride
5 g (0.045 mol), 25.1 g of 1,4'-bis (4-aminophenoxy) benzene (0.086 mol)
l), 11.02 g (0.024 mol) of p-aminobenzoic acid [tris (methacryloyl) pentaerythritol] ester as a terminal-modified amine was added as a powder, and the mixture was stirred for 3 hours on ice and stirred for 24 hours at room temperature to obtain polyamide. The acid was synthesized. The carboxyl group / -COOH of the polyamic acid modified at both ends was 258.3. 597 parts by weight of the polyamic acid solution thus obtained (solid content = 1
00 parts by weight), 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone (hereinafter referred to as B
(Abbreviated as TTB: λmax = 340 nm, manufactured by NOF Corporation)
2 parts by weight, 2 parts by weight of N-phenylglycine, 32 parts by weight of 3EG-A (manufactured by Kyoeisha Chemical Co., Ltd .; triethylene glycol diacrylate) and 0.5 part by weight of 1H-tetrazole as a photosensitizer were added. To give a varnish of a photosensitive polyimide resin (photosensitive resin composition) that can be alkali-developed.

Example 1 <Effect of Removal of Alkaline Component by Acid Rinse Solution> Synthesis Example 1
The varnish synthesized in (1) was applied on a 4-inch silicon wafer substrate by a spinner, and dried on a hot plate at 70 ° C. for 6 minutes to form a coating film having a thickness of about 15 μm. The entire surface of the substrate on which the coating film was formed was exposed with PLA-501F (manufactured by Canon Inc.), and then exposed to a developing solution ZDA-1500 (aqueous developing solution containing tetramethylammonium hydroxide: manufactured by Zeon Corporation) for 5 minutes. Dipped. Next, after immersing and rinsing in water for 30 seconds, the film was further immersed in an acidic rinsing liquid (an aqueous solution containing lactic acid as an acidic compound at a predetermined concentration) for a predetermined time, and then the film was dried by blowing nitrogen gas. A dried silicon wafer substrate with a film is treated with 20 mmol hydrochloric acid aqueous solution 20.
and then immersed in the same for 1 hour to extract tetramethylammonium hydroxide, and quantitatively analyze tetramethylammonium hydroxide by ion chromatography.
Tetramethylammonium hydroxide (alkaline component) remaining in the film formed on the inch silicon wafer substrate
The amount was measured. The results are shown in Table 1.

[Examples 2 to 4] An experiment was conducted in the same manner as in Example 1 except that the acidic compound constituting the acidic rinsing liquid was changed from lactic acid to acetic acid, oxalic acid and nitric acid. The results are shown in Table 1.

Comparative Example 1 An experiment was performed in the same manner as in Example 1 except that water was used as the rinsing liquid. The results are shown in Table 1.

[Reference Example 1] An experiment was performed in the same manner as in Example 1 except that the immersion treatment step (rinsing) with an acidic rinsing liquid was not performed. The results are shown in Table 1. The concentration of the remaining alkali component in Reference Example 1 indicates the amount of the alkali component remaining in the film due to alkali development.

[0094]

[Table 1] (Footnote) * 100> indicates that the residual alkali component amount is 100 μg or less.

As is evident from the results in Table 1, as much as 6158 μg of the alkali component remains without the washing treatment (rinsing) (Reference Example 1). When rinsing with water (Comparative Example 1)
Also, as much as 4750 μg or more of the alkaline component remains. On the other hand, by performing a washing treatment with an acidic rinse solution (Examples 1 to 4), the alkali component can be efficiently removed.

Example 5 <Improvement of Film Properties by Acid Rinse Solution> The varnish synthesized in Synthesis Example 1 was applied on a 4-inch silicon wafer substrate by a spinner, and dried at 70 ° C. for 6 minutes on a hot plate. And a coating film having a thickness of about 15 μm. The entire surface of the substrate on which the coating film was formed was exposed with PLA-501F (manufactured by Canon Inc.), and then exposed to a developing solution ZDA-1500 (aqueous developing solution containing tetramethylammonium hydroxide: manufactured by Zeon Corporation) for 5 minutes. Dipped. Next, the film was immersed in an acidic rinsing liquid (an aqueous solution containing lactic acid as an acidic component at a predetermined concentration) for a predetermined time, and then the film was dried by blowing nitrogen gas. This silicon wafer substrate with a film is placed under a nitrogen atmosphere.
Heat treatment was performed at 350 ° C. for 2 hours to complete imidization. The silicon wafer substrate was treated with 50% hydrofluoric acid, and the polyimide film was peeled off from the silicon wafer substrate, washed sufficiently with water, and dried at 130 ° C. for 2 hours to obtain a polyimide film. Table 2 shows the physical properties of this polyimide film.

[Examples 6 and 7] An experiment was conducted in the same manner as in Example 5 except that the acidic compound constituting the acidic rinse solution was changed from lactic acid to acetic acid, oxalic acid and nitric acid. The results are shown in Table 2.

Comparative Example 2 An experiment was performed in the same manner as in Example 5, except that water was used as the rinsing liquid. The results are shown in Table 2.

[Reference Example 2] The varnish synthesized in Synthesis Example 1 was applied on a 4-inch silicon wafer substrate by a spinner.
Dry on a hot plate at 70 ° C for 6 minutes to a thickness of about 15μ.
m was formed. PL is applied to the substrate on which the coating is formed.
A-501F (manufactured by Canon Inc.)
Heat treatment was performed at 350 ° C. for 2 hours in a nitrogen atmosphere to form a polyimide film. The silicon wafer substrate was treated with 50% hydrofluoric acid, and the polyimide film was peeled off from the silicon wafer substrate, washed sufficiently with water, and dried at 130 ° C. for 2 hours to obtain a polyimide film. Table 2 shows the physical properties of this film. The physical properties of the film show the original properties of the polyimide film when not subjected to alkali development.

[0100]

[Table 2] (Footnote) * Tensile strength and tensile elongation were measured using a tensile tester (Autograph AGS-5kNG: manufactured by Shimadzu Corporation).

As is clear from the results shown in Table 2, the physical properties of the film imidized without the alkali developing treatment show high tensile strength and high tensile elongation (Reference Example 2). However, the properties of the film which was rinsed with water after alkali development and then imidized were clearly lower than those of Reference Example 2 (Comparative Example 2). On the other hand, the physical properties (Examples 5 to 7) of the polyimide film imidized by the heat treatment after the cleaning treatment with the acidic rinsing solution have been recovered to a considerable extent, and the type and concentration of the acidic compound, It can be seen that when the processing conditions are optimized, the polyimide film is recovered to almost the original physical property value. In particular, when the treatment is performed under the condition that the residual amount of the alkali component (residual value in the polyamic acid film per one 4-inch silicon wafer substrate) is 100 μg or less, the physical properties of the obtained polyimide film are different from those of the polyimide film not subjected to the alkali developing treatment. Show close values.

[Example 8] <Effect of suppressing film peeling from SUS substrate during rinsing process> Experiment No. 1 SUS3 fixed on a silicon wafer substrate with double-sided tape
The varnish synthesized in Synthesis Example 1 was applied by spin coating on 04 (metal foil having a thickness of 25 μm). The substrate was dried in an oven at 80 ° C. for 20 minutes, and a coating having a thickness of about 15 μm was
It was fabricated on a US substrate. On the substrate on which this coating film was formed,
PLA-501 using a relief evaluation mask manufactured by Toppan Printing Co., Ltd.
F at an exposure energy of 1500 ml / cm ² ,
Next, development was performed with an alkali developer (ZDA-2500: a developer made by Nippon Zeon Inc. containing tetramethylammonium hydroxide as a main component). Next, it was immersed and rinsed for 90 seconds in an acidic rinsing solution containing 0.05 mol of lactic acid as an acidic compound and dimethylacetamide as an organic solvent. The pattern obtained by development is heated at 350 ° C.
Heat treatment was performed for a time to obtain a patterned polyimide film. The state of separation at the interface between the polyimide film and the SUS substrate was confirmed by observation with an electron microscope. Table 3 shows the results. Experiment Nos. 2 to 32 The experiment was performed in the same manner as in Experiment No. 1 except that the kind and concentration of the acidic compound and the kind and concentration of the organic solvent were changed as shown in Table 3. Table 3 shows the results.

[0103]

[Table 3]

(Footnote) * Effect of Suppressing Film Peeling The state of peeling at the interface between the polyimide film and the SUS substrate was observed with an electron microscope and evaluated according to the following criteria. A: No peeling of the polyimide film occurred. ：: A fine pattern having a width of not more than 20 μm and peeling was observed in a very small portion, but within an acceptable range. Δ: Peeling is observed in a thin pattern having a width of 20 μm or less. X: Many pattern peelings are observed or peeling due to pattern expansion is observed.

[Example 9] <Effect of improving adhesion between polyimide film and chromium sputtered film> SUS fixed on a silicon wafer substrate with double-sided tape
The varnish synthesized in Synthesis Example 1 was applied by spin coating on 304 (metal foil having a thickness of 25 μm). The substrate was dried in an oven at 80 ° C. for 20 minutes, and a coating having a thickness of about 15 μm was
It was fabricated on a US substrate. On the substrate on which this coating film was formed,
After exposure with PLA-501F at an exposure energy of 1500 ml / cm ² , an alkali developer (ZDA-250
0: ZEON developer) for 5 minutes. Then
It was immersed and rinsed for 90 seconds in an aqueous solution (acid rinse solution) containing 0.05 molar concentration of lactic acid as an acidic compound and 2% by weight of dimethylacetamide as an organic solvent. This substrate was heat-treated at 350 ° C. for 2 hours in a nitrogen atmosphere to obtain a polyimide film. A chromium metal film was formed on the polyimide film by a sputtering method. The adhesion between the polyimide film and the metal chromium film formed on the SUS substrate was measured by the Sebastian method. Table 4 shows the results.

Example 10 An experiment was performed in the same manner as in Example 9 except that the temperature during rinsing was changed from 23 ° C. to 60 ° C. Table 4 shows the results.

[Examples 11 to 12] An experiment was performed in the same manner as in Example 9 except that the composition of the acidic rinse solution was changed as shown in Table 4. Table 4 shows the results.

Comparative Example 3 An experiment was performed in the same manner as in Example 9 except that water was used as the rinsing liquid. Table 4 shows the results.

Reference Example 3 An experiment was carried out in the same manner as in Example 9 except that a polyimide film was formed by heat treatment without performing alkali developing and washing with an acidic rinse solution after the entire surface exposure. Table 4 shows the results. The adhesion of the polyimide film indicates the original value of the polyimide film.

[0110]

[Table 4] (Footnote) * Adhesion: Measured according to the Sebastian method.

As is clear from the results shown in Table 4, the adhesion between the polyimide film directly imidized without alkali development and the chromium metal film is high (Reference Example 3). When water was used as the rinsing liquid (Comparative Example 3), the residual concentration of the alkali component was high, and the polyimide film obtained by imidization in that state had significantly reduced adhesion. In contrast, when the acidic rinsing liquid was used (Examples 9 to 12), the original adhesion of the polyimide film was restored. Also, when lactic acid is used (Examples 9, 10, and 12), the effect of recovering the adhesion of the polyimide film is larger than when nitric acid is used as the acidic compound (Example 11).

[0112]

According to the present invention, when a pattern is formed by using a photosensitive polyimide resin which can be alkali-developed, after the alkali development, a washing treatment with a normal rinsing liquid such as water, alcohol, or a mixture of water and alcohol can be carried out. If a large amount of the alkali component remains in the film and is imidized as it is, the mechanical properties of the resulting polyimide film are significantly reduced, and many problems such as the performance of the insulating film and defects in the electronic device manufacturing process are caused. In contrast, according to the present invention,
Simply by washing with an acidic water rinse solution, it is possible to recover the physical properties of the polyimide film imidized by the heat treatment while suppressing peeling during the processing step, and also to recover the adhesive force of feeling with the metal thin film. be able to. The present invention is applicable to alkaline development for manufacturing semiconductor devices, direct wiring forming parts for suspension parts supporting hard disk heads, surface protective films, interlayer insulating films, cover coating for flexible copper-clad boards, and build-up insulating films. It can be suitably applied when using a photosensitive polyimide resin of a mold.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kei Sakamoto 1-2-1, Yakko, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Zeon Corporation General Development Center (72) Inventor Yasuhiro Yoneda Kamodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa 4-1-1 1-1 Inside Fujitsu Limited (72) Inventor Takao Yokouchi 4-1-1 1-1 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Yasuo Naganuma, Nakahara-ku, Kawasaki City, Kanagawa Prefecture 4-1-1 Odanaka Fujitsu Limited

Claims (5)

[Claims] 1. A rinsing solution used when a coating film is formed on a substrate using a photosensitive polyimide resin, exposed to light, developed with an alkali, and then washed, and is measured in an aqueous solution at 25 ° C. photosensitive polyimide resin rinse liquid acid dissociation exponent pK _a that is equal to or comprising an aqueous solution containing 5.0 or less of acidic compounds. 2. The method according to claim 1, wherein the concentration of the acidic compound is 0.005 to 10.
The rinsing liquid according to claim 1, wherein the rinsing liquid is in a range of 0M. 3. An aprotic polar solvent in an amount of 0.01 to 30.
2. The rinsing liquid according to claim 1, further comprising a weight% of the rinsing liquid. 4. A photosensitive polyimide resin comprising: (A) a polyamic acid having an actinic radiation functional group, (B) a photosensitive auxiliary having a photopolymerizable functional group, and (C) a photopolymerization initiator. The rinsing liquid according to claim 1, which is a resin composition. 5. A coating film is formed on a substrate using a photosensitive polyimide resin, exposed in a pattern from the coating film, developed using an alkali developer or an aqueous alkali solution, and then formed by development. washed been relief pattern in the rinse solution, further, the step of heat-treating, in a method of forming a pattern of polyimide film on a substrate, as a rinse, an acid dissociation exponent pK _a, measured in aqueous solution at 25 ° C. A pattern forming method using an aqueous solution containing an acidic compound of 5.0 or less.