JP3477390B2 - Release agent composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resist stripping composition (hereinafter referred to as a stripping composition). More specifically, it relates to a stripping composition for removing a resist used in a lithography technique in the technical field of semiconductor devices and LCDs.

[0002]

2. Description of the Related Art When manufacturing a semiconductor device or LCD,
PVD (Physical Vapor Deposition) and CVD (Chemical Vapor Deposition)
After forming a conductive film or an insulating film by a method such as lithography, form a predetermined resist pattern on the thin film by lithography, and use this as an etching resist to selectively etch and remove the lower thin film, and then completely remove the resist. A step of removing is taken. However, as the degree of integration of semiconductor elements increases, the post-baking temperature of the resist film after development is increased or plasma etching or reactive ion etching (RIE treatment) is performed in order to further improve the processing accuracy of the substrate after resist film formation. ), It is becoming more and more common to introduce processing techniques such as ion implantation, and it becomes very difficult to peel off a resist film that has been altered or hardened by such high energy treatment using a conventional peeling agent. ing. For example, a stripping solution composition prepared by blending a nitrogen-containing organic hydroxy compound with a carboxy group-containing organic compound (JP-A-7-
No. 219240), the stripping solution composition has insufficient strippability, and a stripping solution composition containing an organic acid such as acetic acid, lactic acid or hydroxyacetic acid, benzyl alcohols and water as essential components (special When using Kaihei 4-361265), the releasability is insufficient.

[0003]

DISCLOSURE OF THE INVENTION The present invention is directed to a resist which has undergone high energy treatment and which has been altered or cured.
An object of the present invention is to provide a stripping agent composition having excellent strippability and a resist stripping method using the stripping agent composition.

[0004]

The present invention provides (1) polyvalent carboxylic acid and / or its salt and water 30 to 9
9.9 wt% and the formula (II): R ² [(X) (AO) _k R ³ ] _m (II) (In the formula, R ² is a hydrogen atom or a hydrocarbon having 1 to 8 carbon atoms.
Group, X is —O— group, —COO— group, —NH— group, or —
N ((AO) _n H) -group , k and n are each independently
An integer of 1 to 20, A is an alkylene group having 2 or 3 carbon atoms,
R ³ is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and m is 1
~ Represents an integer of 8) represented by alkylene oxide
Compound, alcohol, ether, carbonyl compound, S
From tellurium, phenol, nitrogen-containing compounds and sulfur-containing compounds
And at least one organic solvent selected from the group consisting of
H is less than 8 and the polyvalent carboxylic acid is a compound represented by the formula (I), which does not contain a fluorine-containing compound and nitric acid, and a resist stripper composition ( 2 ) polyvalent carboxylic acid and / or Or its salt and water 30-9
9.9% by weight and at least one organic solvent selected from the group consisting of alkylene oxide compounds represented by formula (II), alcohols, ethers, carbonyl compounds, esters, phenols, nitrogen-containing compounds and sulfur-containing compounds. ( 3 ) Polycarboxylic acid containing, and having a pH of less than 8 and the polycarboxylic acid is a compound represented by the formula (I) and containing no fluorine-containing compound. The first stage dissociation index pK ₁ of the acid is 3.
A resist stripper composition according to (1) or (2), which is 6 or less, and a resist stripping method using the resist stripper composition according to any one of ( 4 ) to ( 3 ) above. .

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The polyvalent carboxylic acid has the formula (I): B-[(R ¹ ) _p- (COOH) _q ] _r (I) (wherein R ¹ has ¹ to 20 carbon atoms). It is a saturated or unsaturated hydrocarbon group consisting of a linear, branched or cyclic skeleton, which may have 1 to 5 oxygen, nitrogen or sulfur atoms and is bonded to the carbon atom of R ^1. The hydrogen atom is -O
It may be substituted with H group, -NH ₂ group, -SH group or -NO ₂ group, and the -COOH group is ^{1 at} the same carbon atom of R 1.
One or more may be bonded, p is 0 or 1, q is an integer of 1 to 40, r is an integer of 1 to 3, the sum of q and r is 2 or more, B is absent or -O. -Group, -CO- group, -N
H-group, -S-group or

[0006]

[Chemical 2]

The group represented by (1) is preferred.

In the formula (I), R ¹ has 1 to 1 carbon atoms.
A hydrocarbon group of 0 is more preferable, and a linear saturated hydrocarbon group having 1 to 4 carbon atoms is particularly preferable. From the viewpoint of resist releasability, q is more preferably an integer of 1 to 5 and 1 or 2
Is particularly preferable.

Specific examples of the polycarboxylic acid represented by the formula (I) include oxalic acid, malonic acid, methylmalonic acid, ethylmalonic acid, dimethylmalonic acid, succinic acid, methylsuccinic acid and 2,2-dimethyl. Succinic acid, glutaric acid, adipic acid, 3-methyladipic acid, sebacic acid, hexadecanedioic acid, 1,2,3-propanetricarboxylic acid,
Saturated polycarboxylic acids such as 1,2,3,4-butanetetracarboxylic acid, polyacrylic acid, polymaleic acid; maleic acid, fumaric acid, citraconic acid, mesaconic acid, cis-aconitic acid, trans-aconitic acid, etc. Unsaturated polycarboxylic acids; hydroxy polycarboxylic acids such as tartaric acid, malic acid and citric acid; amino polycarboxylic acids such as aspartic acid and glutamic acid; poly aromatic compounds such as terephthalic acid, trimellitic acid and naphthoic acid Carboxylic acid; polyvalent carboxylic acid having an alicyclic ring such as 1,2-cyclohexanedicarboxylic acid; and polycarboxylic acid having a heterocyclic ring such as 2,3-pyrazinedicarboxylic acid. Among these, saturated polyvalent carboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, polyacrylic acid, and polymaleic acid; tartaric acid, malic acid, etc.
Hydroxy polycarboxylic acids such as citric acid; amino polycarboxylic acids such as aspartic acid and glutamic acid are particularly preferable.

First-stage dissociation index pK _{1 of} polycarboxylic acid
Is preferably 3.6 or less, and more preferably 1 to 3 from the viewpoint of resist releasability.

The dissociation index pK ₁ of the polycarboxylic acid in the first step is determined as follows. That is, a polyvalent carboxylic acid (represented by H _n A in the general formula) dissociates in stages as follows when dissolved in water.

[0012]

[Equation 1]

Here, the dissociation constant (K ₁ ) of the first stage is defined as follows. K ₁ = [H _n-1 A ⁻ ] [H ⁺ ] / [H _n A] The logarithm of the reciprocal of K ₁ at this time is the dissociation index (pK) of the first stage.
₁ ). _{pK 1 = log (1 / K} 1) = - logK 1

In the present specification, pK ₁ when a salt of polyvalent carboxylic acid is used means pK of polyvalent carboxylic acid.
_Shall mean ₁ .

Examples of the salt of polyvalent carboxylic acid include salts of polyvalent carboxylic acid with a basic organic compound or a basic inorganic compound. As the basic organic compound, a primary amine,
Secondary amine, tertiary amine, imine, alkanolamine, amide, basic heterocyclic compound, quaternary ammonium hydroxide and the like can be mentioned. Examples of the basic inorganic compound include ammonia, sodium hydroxide, potassium hydroxide, calcium hydroxide and the like. Among these, ammonium salts of polyvalent carboxylic acids and salts of polyvalent carboxylic acids with basic organic compounds are preferable from the viewpoint of avoiding contamination with metal ions. The polycarboxylic acid salts may be used alone or in combination of two or more.

The polycarboxylic acid and / or its salt may be used alone or in admixture of two or more.

The content of the polyvalent carboxylic acid and / or its salt in the stripper composition is preferably 0.01 to 90% by weight, more preferably 0.05 to 85% by weight, It is more preferably 0.1 to 70% by weight. Further, the content is preferably 0.01% by weight or more from the viewpoint of obtaining good resist peelability, and is preferably 90% by weight or less from the viewpoint of containing an appropriate amount of water.

The water used in the present invention is ionic substances such as ion-exchanged water, pure water and ultrapure water, and particles in consideration of the fact that the release agent composition is used in the field of manufacturing semiconductor devices and LCDs. It is preferable to reduce the above as much as possible.

The content of water in the release agent composition is 1
It is preferably from 0 to 99.99% by weight, and from 15 to 9
It is more preferably 9.95% by weight, and 30 to 9
More preferably, it is 9.9% by weight. Further, the content is 10 from the viewpoint of obtaining good resist peelability.
It is preferably at least 10% by weight, and from the viewpoint of containing an appropriate amount of polyvalent carboxylic acid and / or salt thereof, 99.99
It is preferably not more than weight%.

The pH of the stripper composition of the present invention is less than 8, preferably 0.1 to 7, more preferably 0.3 to 5, and particularly preferably 0, from the viewpoint of obtaining good resist strippability. .5-3.

The stripper composition of the present invention may further contain an organic solvent from the viewpoint of promoting penetration of polyvalent carboxylic acid and / or salt thereof or water into the resist and improving resist strippability. Good.

The organic solvent is represented by the formula (II): R ² [(X) (AO) _k R ³ ] _m (II) (wherein R ² is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, X is an —O— group, a —COO— group, a —NH— group, or —
N ((AO) _n H) -group, k and n are each independently an integer of 1 to 20, A is an alkylene group having 2 or 3 carbon atoms,
R ³ is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and m is 1
Represented by an integer of 1 to 8), one or more compounds selected from the group consisting of alkylene oxide compounds, alcohols, ethers, carbonyl compounds, esters, phenols, nitrogen-containing compounds and sulfur-containing compounds.

In the formula (II), R ² is preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. R ³ is preferably a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, and more preferably a hydrogen atom or a hydrocarbon group having 1 or 2 carbon atoms. m
Is preferably an integer of 1 to 3, more preferably 1 or 2.

Specific examples of the alkylene oxide compound represented by the formula (II) include methyl ether of ethylene glycol, ethyl ether, propyl ether, butyl ether, hexyl ether, phenyl ether, benzyl ether, dimethyl ether, diethyl ether,
Butyl methyl ether, ethyl propyl ether, butyl ethyl ether, dipropyl ether, dibutyl ether, etc .; corresponding diethylene glycol alkyl ether, triethylene glycol alkyl ether, etc .; tetraethylene glycol methyl ether, butyl ether, etc .; Examples thereof include glycol alkyl ether and dipropylene glycol alkyl ether.

The alcohol is represented by the formula (III): R ^1- (OH) _m (III) (wherein R ¹ and m are the same as those defined in the formulas (I) and (II)). The compounds represented may be mentioned.

Examples of the ether include compounds represented by the formula (IV): R ¹ —O—R ¹ (IV) (wherein R ¹ is the same as defined in the formula (I)).

The carbonyl compound has the formula (V):

[0028]

[Chemical 3]

A compound represented by the formula (wherein R ¹ is the same as defined in the formula (I)) can be mentioned.

The ester is represented by the formula (VI): R ¹ -COOR ⁴ (VI) (wherein R ¹ is the same as defined in the formula (I), R ⁴ is a hydrocarbon group having 1 to 5 carbon atoms. Is shown). In the formula (VI), R ⁴ has 1 carbon atom.
Alkyl groups of 3 are preferred.

The phenol is represented by the formula (VII):

[0032]

[Chemical 4]

(In the formula, R ⁵ is a saturated or unsaturated hydrocarbon group having a linear, branched or cyclic skeleton having 1 to 9 carbon atoms, and the hydrocarbon group of R ⁵ is 1 to 5 ^May have an oxygen atom, a nitrogen atom or a sulfur atom, and the hydrogen atom bonded to the carbon atom of R ⁵ is —OH group, —NH ₂
Group, may be substituted by -SH group or -NO ₂ group,
s is an integer of 0 to 5, and t is an integer of 1 to 3).

The nitrogen-containing compound is not particularly limited as long as it contains a nitrogen atom and has a molecular weight of 200 or less. The sulfur-containing compound is not particularly limited as long as it is a compound containing a sulfur atom and having a molecular weight of 200 or less.

Among the organic solvents, from the viewpoint of permeability, diethylene glycol monobutyl ether and diethylene glycol monohexyl ether which are alkylene oxide compounds; propanol, butanol and pentanol which are alcohols; trioxane and methylal which are ethers; acrolein which is a carbonyl compound. And methyl ethyl ketone; ester acetoacetic nitrile and ethyl formate; phenol benzylphenol; nitrogen-containing compounds dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone and dimethylimidazolidinone; sulfur-containing compound dimethylsulfoxide And sulfolane are preferred. You may use these organic solvents individually or in mixture of 2 or more types.

The melting point of the organic solvent is preferably 60 ° C. or lower, more preferably 30 ° C. or lower, still more preferably 10 ° C. or lower, from the viewpoint of ensuring the resist peeling property and workability.

From the viewpoint of promoting the permeation of the polyvalent carboxylic acid and / or its salt or water into the resist and improving the resist releasability, the organic solvent is used in water at 25 ° C.
It is preferably 5% by weight or more, more preferably 4% by weight or more, further preferably 7% by weight or more.

The content of the organic solvent in the stripper composition is such that the total amount of the polycarboxylic acid and / or its salt and water is 100.
It is preferably 0.5 to 900 parts by weight, and more preferably 5 to 300 parts by weight, based on parts by weight.
In addition, the content is 0.5 from the viewpoint of obtaining high penetration power.
The amount is preferably not less than 900 parts by weight, and more preferably not more than 900 parts by weight from the viewpoint of good resist strippability.

The release agent composition of the present invention is not particularly limited and can be obtained by mixing the above compounds.

The release agent composition of the present invention is used for semiconductor devices and L
Since the resist adhered on a member such as an inorganic member such as a CD can be easily removed without damaging those members, it can be suitably used for the peeling of the resist in the manufacturing process of semiconductor elements, LCDs and the like. is there.

As a method of removing the resist on the substrate using the remover composition of the present invention, for example, one wafer or a plurality of wafers to be processed are set in a jig and then the wafer is set. Immersing in the release agent composition of the present invention,
A method of stripping while swinging a jig or applying mechanical stress such as ultrasonic waves or jet to the stripping agent composition, or spraying or spraying the stripping agent composition of the present invention on a wafer to be processed.
A preferred method is a peeling treatment. The temperature of the release agent composition at that time is 10 to 100 from the viewpoint of workability.
C. is preferable, and more preferably 15 to 70.degree. After the peeling process, the peeling agent composition remaining on the wafer is preferably removed by rinsing with a solvent such as water or 2-propanol.

[0042]

EXAMPLES Examples 1 to 6 and Comparative Examples 1 to 3 (however,
Examples 1 to 3 are reference examples) A thickness of 0.5 is formed on a silicon wafer by a sputtering method.
μm aluminum-silica-copper [98.5: 1.0:
0.5 (weight ratio)], and then a naphthoquinonediazide-based positive photoresist for i-line was coated on the alloy film using a spinner. Then, using a hot plate, this wafer was pre-baked at 110 ° C. for 90 seconds to form a photoresist film having a film thickness of 1.5 μm.

This photoresist film was exposed through a photomask of a reduction projection exposure device. Then, paddle development was performed for a certain period of time using a developing solution (2.38% tetramethylammonium hydroxide aqueous solution). The developed photoresist film was rinsed with pure water for 30 seconds and then dried under a nitrogen stream. Then, post-baking treatment was performed at 140 ° C. for 20 minutes, and the metal layer in the opening was dry-etched with chlorine-based gas using this resist pattern as a mask to form metal wiring, and at the same time, the residual resist was denatured and cured. Then, about 70% of the remaining resist was removed by dry ashing to produce a resist that has undergone alteration hardening. This silicon wafer was used for the peel test.

Each component was mixed so as to have a composition shown in Tables 1 and 2 to obtain a release agent composition. The release agent compositions obtained in Examples 1 to 6 and Comparative Examples 1 to 3 were heated to 60 ° C., the silicon wafer was immersed in the release agent composition for 20 minutes, then taken out, and rinsed with 2-propanol. Rinse again with pure water. After drying, the resist pattern of 2 μm × 2 μm formed was magnified 10,000 times with a scanning electron microscope to obtain 10
The peelability of the resist was evaluated by the peeling rate by observing 0 spots. The results are shown in Tables 1-2. The peeling rate was calculated by the following formula.

Peeling rate = (99% or more of resist (area)
Number of peeled resist patterns / 100) x 100

Further, in Tables 1 and 2, the solubility in water "∞"
Indicates that water and the organic solvent can be mixed without limitation.

[0047]

[Table 1]

[0048]

[Table 2]

From the results shown in Tables 1 and 2, the release agent compositions obtained in Examples 1 to 6 have higher release rates than the release agent compositions obtained in Comparative Examples 1 to 3. I understand.

Example 7 The stripping rate was evaluated in the same manner as in Example 1 except that the stripping agent composition obtained in Example 1 was used, and the stripping temperature was 25 ° C. and the time was 5 minutes. The peeling rate is 95%
And good results were obtained.

[0051]

EFFECTS OF THE INVENTION Since the resist stripping composition for resist of the present invention is capable of easily stripping even a resist which has been deteriorated by high energy treatment in a short period of time, it greatly improves the productivity and quality of semiconductor devices and LCDs. It has an effect of contributing. Further, according to the present invention, there is an effect that the resist which has been deteriorated by the high energy treatment can be peeled off easily and in a short time.

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-9-197681 (JP, A) JP-A-10-55993 (JP, A) JP-A-7-271056 (JP, A) JP-A-4- 361265 (JP, A) JP-A-11-52588 (JP, A) JP-A-11-316464 (JP, A) International publication 00/33371 (WO, A1) (58) Fields investigated (Int.Cl. ⁷⁾ , DB name) G03F 7/00-7/42

Claims (4)

(57) [Claims] 1. A polyvalent carboxylic acid and / or its salt, 30 to 99.9% by weight of water, and a compound represented by the formula (II): R ² [(X) (AO) _k R ³ ] _m (II) (formula Where R ² is a hydrogen atom or a hydrocarbon having 1 to 8 carbon atoms
Group, X is —O— group, —COO— group, —NH— group, or —
N ((AO) _n H) -group , k and n are each independently
An integer of 1 to 20, A is an alkylene group having 2 or 3 carbon atoms,
R ³ is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and m is 1
~ Represents an integer of 8) represented by alkylene oxide
Compound, alcohol, ether, carbonyl compound, S
From tellurium, phenol, nitrogen-containing compounds and sulfur-containing compounds
And at least one organic solvent selected from the group consisting of
H is less than 8, the polyvalent carboxylic acid has the formula (I): B - [( R 1) p - (COOH) q] r (I) ( In the formula, R ¹ having 1 to 20 carbon atoms It is a saturated or unsaturated hydrocarbon group having a linear, branched or cyclic skeleton, and may have 1 to 5 oxygen atoms, nitrogen atoms or sulfur atoms, and at the carbon atom of R ¹ The bonded hydrogen atom may be substituted with -OH group, -NH ₂ group, -SH group or -NO ₂ group, and one or more -COOH groups are bonded to the same carbon atom of R ^1. , P is 0 or 1, q is an integer of 1 to 40, r is an integer of 1 to 3, the sum of q and r is 2 or more, B is absent or an —O— group, —CO—
Group, --NH-- group, --S-- group or A compound having a fluorine-containing compound and nitric acid, which is a compound represented by the formula (1). 2. A polycarboxylic acid and / or salt thereof, 30 to 99.9% by weight of water, and a compound represented by the formula (II): R ² [(X) (AO) _k R ³ ] _m (II) (formula Wherein R ² is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, X is —O— group, —COO— group, —NH— group, or —
N ((AO) _n H) -group, k and n are each independently an integer of 1 to 20, A is an alkylene group having 2 or 3 carbon atoms,
R ³ is a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and m is 1
Represented by an integer of 8), one or more organic solvents selected from the group consisting of alkylene oxide compounds, alcohols, ethers, carbonyl compounds, esters, phenols, nitrogen-containing compounds and sulfur-containing compounds. , P
H is less than 8, the polyvalent carboxylic acid has the formula (I): B - [( R 1) p - (COOH) q] r (I) ( In the formula, R ¹ having 1 to 20 carbon atoms It is a saturated or unsaturated hydrocarbon group having a linear, branched or cyclic skeleton, and may have 1 to 5 oxygen atoms, nitrogen atoms or sulfur atoms, and at the carbon atom of R ¹ The bonded hydrogen atom may be substituted with -OH group, -NH ₂ group, -SH group or -NO ₂ group, and one or more -COOH groups are bonded to the same carbon atom of R ^1. , P is 0 or 1, q is an integer of 1 to 40, r is an integer of 1 to 3, the sum of q and r is 2 or more, B is absent or an —O— group, —CO—
Group, —NH— group, —S— group or A group representing a group), which is a release agent composition for a resist containing no fluorine-containing compound. 3. The first stage dissociation index pK of polycarboxylic acid.
3. The resist stripper composition according to claim 1, wherein ₁ is 3.6 or less. 4. The method of claim 1-3 resist peeling method using the resist stripping composition according to any one.