JPH03188449A - Developing solution for photosensitive polyimide precursor and development processing method using the same - Google Patents

Abstract

PURPOSE:To obtain the developing soln. which does not generate fluctuations in pattern sizes within a wafer surface after development processing and can form the uniform patterns in the same developing time in the case of formation of a photosensitive polyimide resin film of <= 3mum film thickness by incorporating specific solvents, methyl alcohol and fluorine surfactant into the developing soln. CONSTITUTION:This developing soln. is formed by incorporating (a) one or >=2 kinds of the solvents selected from N, N-dimethyl formamide, N, N-dimethyl acetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, 1, 3-dimethyl-2- imidazolidinone, N-acetyl-epsilon-caprolactam, gamma-butyrolacton, hexamethyl phosphorylamide, and tetramethylene sulfone, (b) the methyl alcohol and (c) the fluorine surfactant into the soln. The fluctuations in the pattern sizes within the wafer surface after the development processing are eliminated in this way and the good patterns are formed in the same developing time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developer for photosensitive polyimide precursors and a development method using the same.

[Conventional technology]

Conventionally, polyimide resins have been used for glabellar insulating films and surface protective films of semiconductor devices and the like. It is known that this polyimide resin film is formed on a wafer on which semiconductor elements are manufactured by a spinning method or the like. Generally, when etching or patterning a polyimide resin film, a photoresist film is used as a mask material, holes are made (patterned) using an alkaline aqueous solution or a hydrazine solution as an etching solution, and then the unnecessary photo resist film is used as a mask material. The resist film is treated with a stripping solution and removed.

However, recently, attempts have been made to shorten the process by imparting pattern-forming ability to polyimide precursors and making them photosensitive polyimide precursors that do not require the formation and peeling of photoresist films.

To form a pattern on this photosensitive polyimide resin film,
Generally N-methyl-2-pyrrolidone, N.

JP-A No. 58-223149 discloses that a developer containing a polar organic solvent such as N-dimethylacetamide or dimethyl sulfoxide as a main component has a strong affinity for a photosensitive polyimide precursor that has formed a crosslinked structure by exposure to light. This method is disclosed in Japanese Patent Publication No. 62-299846.

However, with the increasing integration of semiconductors, the device area and the wafer size are also increasing, so if the photosensitive polyimide resin film has a relatively thick film thickness of 3 μm or more, the static paddle method or the spray method is required. In such development processes, there was a problem that the pattern dimensions became non-uniform within the wafer surface. This problem is particularly likely to occur when exposure is performed using a contact method.

That is, although a good pattern can be obtained at the center of the wafer, the closer to the edges the patterning becomes insufficient and the pattern cannot be formed in the same developing time.

In general, as a method for improving resolution or developing power and development stability, for positive photosensitive resin compositions, a method of adding a surfactant to a developer consisting of an alkaline aqueous solution is disclosed in JP-A No. 62-32451. , 62-3
No. 2452, No. 63-6548, No. 60-17943
No. 63-175858.

However, these developers cannot be used as developers for photosensitive polyimide precursors.

[Problem to be solved by the invention]

An object of the present invention is to solve the problems of the prior art and to achieve a film thickness of 3.
When forming a photosensitive polyimide resin film of μm or more,
It is an object of the present invention to provide a developer capable of forming a uniform pattern in the same development time without variation in pattern size within the wafer surface after development, and a development processing method using the same.

[Means to solve the problem]

The present invention provides (a) N,N-dimethylformamide, N,
N-dimethylacetamide, dimethyl sulfoxide, N
-Methyl-2-pyrrolidone, 1゜3-dimethyl-2-imidazolidinone, N-acetyl-ε-caprolactam,
A developer for a photosensitive polyimide precursor containing one or more solvents selected from γ-butyrolactone, hexamethylphosphoramide, and tetramethylene sulfone, (b) methyl alcohol, and (C) a fluorine-based surfactant. The present invention relates to a method for developing a photosensitive polyimide resin film, which comprises developing a photosensitive polyimide resin film exposed to light using a developer and the developer.

The fluorine-based surfactant (c) used in the developer of the present invention is preferably one having a perfluoroalkyl group, such as Megafac F-171F-172.
, F-173, and F-177 (all trade names manufactured by Dainippon Ink and Chemicals).

The blending ratio of the fluorine-based surfactant is 0.0 with respect to the total amount of the group (a) solvent and (b) methyl alcohol, from the viewpoint of uniformity of pattern size within the wafer surface and margin of development time.
A range of 2 to 3.0% by weight is preferred, and 0.06 to 0.8% by weight.
A weight percent range is more preferred.

In the developing solution for photosensitive polyimide precursors of the present invention, the blending ratio of methyl alcohol is preferably in the range of 10 to 40% by weight, and 20 to 40% by weight based on the total amount with the solvent of group (a).
If the amount of methyl alcohol, which is more preferably in the range of 30% by weight, is small, the resin film will easily dissolve or cracks will occur during the development process. On the other hand, if the amount is too high, the resin film tends to whiten, a good pattern shape cannot be obtained, and development processing becomes difficult.

In the present invention, solvents other than those mentioned above may be contained within a range that does not adversely affect the developability.

Suitable examples of these solvents include alcohols, polyhydric alcohol derivatives, esters, hydrocarbons, and ethers. There is no restriction on the mixing order of the above (a), (b) and (C).

To carry out the development process using the developer of the present invention, first, a photosensitive polyimide precursor resin composition is applied onto a wafer, etc. by spinning, and then heated at 70 to 130 degrees using a hot air dryer, hot plate, etc. C1 Heat treatment is preferably performed at a relatively low temperature of 90 to 120° C. for one hour or less to form a photosensitive polyimide resin film.

This photosensitive polyimide precursor resin composition is not particularly limited, but it is a photosensitive polyimide precursor represented by the following formula (1) into which a photosensitive group is introduced through an ester bond, a sensitizer, and a photosensitive polyimide precursor. (1) A polyimide precursor with an amine compound having a carbon-carbon double bond added with a photopolymerization initiator, a sensitizer, a bisazide, etc. The following formula (
Preferably, the reaction product represented by 2) is added with an unsaturated compound such as 1,6-hexanediol diacrylate, a photopolymerization initiator, a sensitizer, or the like.

Additionally, the polyimide precursor may include silicon.

Next, the polyimide resin film is exposed to light using a known photolithography technique, and the developing solution of the present invention is used to develop the polyimide resin film at room temperature for 1 to 15 minutes using a developing method such as a static paddle method, a spray method, or a dipping method.
A portion of the pattern (2) is developed. This development time is determined by the thickness of the polyimide resin film and the heat treatment conditions before exposure.

After the development process, the pattern area is thoroughly washed with a rinsing solution to remove development residue.

This rinsing liquid uses an organic solvent or the like that has good miscibility with the developer and does not damage the polyimide resin film. Examples of rinsing liquid include water, methyl alcohol,
Examples include ethyl alcohol, methyl cellosolve, ethyl cellosolve, toluene, and xylene.

After the rinsing treatment, it was immediately spin-dried, and then dried for 30 minutes at 120-160°C using a dryer in a nitrogen atmosphere.
A polyimide resin film can be obtained by heat treatment at 00° C. for 30 minutes and then at 350° C. for 60 minutes.

〔Example〕

The present invention will be specifically explained below using examples.

Example 1 4,4'-diaminodiphenyl ether 6 under nitrogen flow
6.81 g (0.4 mol), 1,3-bis(aminopropyl)tetramethyldisiloxane 10.36 g (0
,05 mol) and 10.15 g (0.05 mol) of 4,42-diaminodiphenyl ether-3-carbonamide.
was stirred and dissolved in 1000 g of N-methyl-2-pyrrolidone, and 45.49 g of pyromellitic dianhydride (0,
25 mol), 3.3'4.4' -benzophenonetetracarboxylic dianhydride (67.19 g (0.25 mol)) was gradually added and reacted at room temperature for 3 hours to form a polyamide with a viscosity of 60 poise (25°C). An acid silicon type intermediate solution was obtained.

1.71 g (0.01 mol) of 3-(N,N-dimethylamino)propyl methacrylate was added to 20 g of this solution.
, 0.40 g (0,001 mol) of 2,6-di(4'-azidobenzal)-4-carboxycyclohexane was dissolved and then heated at 5F using a 1 μm pore filter.
I met you.

The resulting photosensitive polyimide precursor resin composition was applied onto a 5-inch silicon wafer by spinning at 3,000 rpm for 60 seconds, and then heated at 90°C for 7 seconds using a hot plate.
A heat treatment (prebaking) was performed for 0 seconds to form a polyimide resin film having a thickness of 7 μm.

Next, this resin film was exposed to light through a negative chrome mask using a contact type exposure device (manufactured by Mikasa, M-3LD type) equipped with an IK- high pressure mercury lamp, and then N-methyl-2- Pyrrolidone 74.6% by weight, methyl alcohol 24.8% by weight, fluorine surfactant F-171.0,
Wet and spread a developer consisting of 5% by weight on the resin crotch, and
The film was developed by the static paddle method at 130°C for 130 seconds. Next, rinsing treatment with ethyl alcohol was performed for 30 seconds using a shower method.

Next, use a dryer in a nitrogen atmosphere at 150°C for 30 minutes.
Next, heat treatment was performed at 200° C. for 30 minutes and then at 350° C. for 60 minutes to obtain a polyimide resin film having a thickness of 3 μm.

The second resin film had a good pattern shape with no variation in pattern size (through hole diameter of 80 μm) within the wafer surface.

Example 2 4,4'-diaminodiphenyl ether 1 under nitrogen flow
00.1 g (0.5 mol) was dissolved in 418 g of N-methyl-2-pyrrolidone to prepare an amine solution. 109.05 g (0.5 mol) of pyromellitic dianhydride with N,
It was dissolved in 279 g of N-dimethylacetamide to obtain an acid solution. The acid solution was added to the amine solution at 60°C and reacted for 3 hours to obtain a polyimide acid intermediate solution with a viscosity of 60 poise (25°C).

Add 1.15 g of Michler's ketone to 50 g of this solution and add 30
of N,N-dimethylacetamide and 10.2 g of diethylaminoethyl methacrylate dissolved in 1
A solution dissolved in 0 g of N,N-dimethylacetamide was mixed and then pressurized for 5 times using a ROM hole filter.

The obtained photosensitive polyimide precursor resin composition was applied onto a 5-inch silicon wafer by spinning at 350 rpm for 60 seconds, and then heated at 90° C. for 60 seconds using a hot plate.
A heat treatment was performed for a second to form a polyimide resin film having a thickness of 7 μm.

Next, the resin film, which was exposed, developed, and rinsed in the same manner as in Example 1, had a good pattern shape with no variation in pattern size within the wafer surface. The film thickness after heat treatment at 350°C was 3 μm.

Example 3 22.2 g (0
,05 mol), 21.3 g (0.05 mol) of 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldisiloxane dianhydride and 3.3' 4
．． 4'-benzophenonetetracarboxylic dianhydride 32
．． 2g (0.1 mol) of N-methyl-2-pyrrolidone 2
After that, 40.0 g (0.2 mol) of 4,4'-diaminodiphenyl ether was added thereto, and the mixture was stirred at room temperature for 4 hours.

Next, add isocyanate (ethyl methacrylate) to this solution.
15.5 g (0.1 mol) was added and stirred at room temperature for 10 hours.

Furthermore, when ethanol 80II11 was added and poured into water 82, the polymer was precipitated as a thread-like solid.

For 10 g of this polymer, 0.4 g of benzophenone, 0.1 g of Michler's ketone, and 1.5 g of 1.6-hexanediol diacrylate were dissolved in 38 g of N-methyl-2-pyrrolidone with stirring, and then a filter with 1 μm pores was used. A photosensitive polyimide precursor resin composition having a viscosity of 50 poise was obtained by applying pressure. This composition was applied onto a 5-inch silicon wafer by spinning at 3000 rpm for 60 seconds, and then heated at 95°C using a hot plate for 60 seconds.
Heat treatment was performed for 0 seconds to form a polyimide resin film having a thickness of 9 μm.

Next, the resin film, which was exposed, developed, and rinsed in the same manner as in Example 1, had a good pattern shape with no variation in pattern size within the wafer surface. The film thickness after heat treatment at 350°C was 4.5 μm.

Example 4 The same photosensitive polyimide precursor resin composition as in Example 1 was
After spinning for 60 seconds at 200 rpm onto a 1-inch silicon wafer, it was heated at 95°C on a hot plate for 1
After performing heat treatment for 30 seconds to form a polyimide resin film with a thickness of 9 μm, it was exposed in the same manner as in Example 1, and 74.8% by weight of N-methyl-2-pyrrolidone, 24.9% by weight of methyl alcohol, and Fluorine surfactant F-177,
160 at 23°C using a developer consisting of 0.3% by weight.
After developing and rinsing using the second stationary paddle method,
A polyimide resin film having a thickness of 5 μm was obtained by heat treatment.

This resin film had a good pattern shape with no variation in pattern size within the wafer surface.

Example 5 The same photosensitive polyimide precursor resin composition as in Example 1 was
After coating on an inch silicon wafer by spinning at 200 rpm for 30 seconds, the coating was applied at 95°C using a hot plate.
A heat treatment was performed for 180 seconds to form a polyimide resin film with a thickness of 14.5 μm.

Next, reduce projection exposure bag W (manufactured by Canon: FPA-15
50) through a negative chromium mask, development was performed using the same developer as in Example 1 for 220 seconds by the static paddle method, and rinsing treatment with ethyl alcohol was performed for 40 seconds by the shower method.

Next, using a dryer in a nitrogen atmosphere, it was heated at 120°C for 60 minutes, then at 200°C for 30 minutes, and then at 350°C for 60 minutes.
A heat treatment was performed for a minute to obtain a polyimide resin film having a thickness of 7 μm. This resin film had a good pattern shape with no variation in pattern size (through hole diameter of 15 μm) within the wafer surface.

Comparative Example 1 Spinning coating and development were carried out in the same manner as in Example 1, except that a mixed solution consisting of 75% by weight of N-methyl-2-pyrrolidone and 25% by weight of methyl alcohol was used as a developer, and a polyimide resin film was formed. formed a pattern.

This resin film has a good pattern shape at the center of the wafer, but the closer it gets to the edge of the wafer, the more undeveloped it is.
The pattern dimensions within the wafer surface were non-uniform.

Comparative Example 2 20% by weight of N-methyl-2-pyrrolidone as a developer,
Methyl alcohol 10% by weight and ethylene glycol 7
A pattern of a polyimide resin film was formed by performing spinning coating and development in the same manner as in Example 1, except that a mixed solution containing 0% by weight was used. Crank occurred in this resin film during development time of 60 to 90 seconds.

Comparative Example 3 Spinning coating and development were carried out in the same manner as in Example 1, except that a mixed solution of 80% by weight N-methyl-2-pyrrolidone and 20% by weight of water was used as a developer to form a pattern on a polyimide resin film. was formed. The pattern dimensions within the wafer surface were non-uniform, and the development process required 300 seconds.

〔Effect of the invention〕

According to the developer for photosensitive polyimide precursors and the development method using the same of the present invention, there is no variation in the pattern dimensions within the wafer surface after development, and it is possible to form a good pattern in the same development time. can.

Claims (1)

[Claims] 1. (a) N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N- A photosensitive material containing one or more solvents selected from acetyl-ε-caprolactam, γ-butyrolactone, hexamethylphosphoramide, and tetramethylene sulfone, (b) methyl alcohol, and (c) a fluorine-based surfactant. developer for polyimide precursors. 2. The proportion of the fluorosurfactant is 0.02 with respect to the total amount of the group (a) solvent and (b) methyl alcohol.
The developer for a photosensitive polyimide precursor according to claim 1, wherein the content is 3.0% by weight. 3. The developing solution for a photosensitive polyimide precursor according to claim 1, wherein the blending ratio of methyl alcohol is 10 to 40% by weight based on the total amount of the solvent of group (a). 4. A method for developing a photosensitive polyimide resin film, which comprises developing the exposed photosensitive polyimide resin film using the developer for a photosensitive polyimide precursor according to claim 1.