JP2003107754A - Photoresist release liquid composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoresist release liquid composition for easily releasing a photoresist film applied on a substrate, a photoresist layer remaining after etching the photoresist film applied to the substrate, a photoresist residue remaining after ashing subsequent to the etching of the photoresist layer or the like in a short period of time, not corroding various materials, in particular scarcely corroding silicon and manufacturing highly accurate circuit wiring. SOLUTION: The photoresist release liquid composition composed of an amine compound and an amine polymer easily release the remaining photoresist residue or the like in a short period of time and does not corrode the various materials in the release process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION Photoresists used when utilizing lithography techniques include integrated circuits such as ICs and LSIs, display devices such as LCDs and EL devices, printed circuit boards, micromachines, DNA chips, etc. It is used in a wide range of fields. The present invention relates to a photoresist stripping composition used for stripping a photoresist from the surface of a material such as various substrates.

[0002]

2. Description of the Related Art In recent years, processes for semiconductor elements containing silicon such as polysilicon and liquid crystal display panels have come to be widely used, and a photoresist stripping solution that does not corrode silicon has been required. ing. Also, although most substrates that use photoresist are silicon, there is usually a layer of silicon oxide that does not easily corrode. However, recently, the number of processes for performing a photoresist stripping process after a long-time process or a process for thinning an oxide layer is increasing, and silicon is likely to be corroded. Conventionally, an alkaline stripping solution has been used for removing photoresist. For example, TOK 106 from Tokyo Ohka is alkanolamine and dimethyl sulfoxide, EKC technology
EKC265 is a solution of alkanolamine, hydroxylamine, catechol and water. Generally, these alkaline compound photoresist stripping compositions are used in the photoresist stripping step, but the photoresist stripping solution containing no water has a drawback that the metal-containing components cannot be completely removed by dry etching. ing. In order to improve this drawback, the amine solution containing water has a drawback of corroding silicon, aluminum and aluminum alloy. On the other hand, the liquid containing hydroxylamine does not corrode silicon or the like even when it contains water. But hydroxylamine is expensive,
It has the drawback of being very easily decomposed. In addition, there is a drawback that hydroxylamine cannot be effectively protected against corrosion unless it is used in a large amount.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the stripping solution in the prior art, and to apply a photoresist film on a substrate or a photoresist film applied on a substrate. The photoresist layer remaining after etching, or the photoresist residue remaining after etching the photoresist layer can be easily removed in a short time without corroding various materials, especially corroding silicon It is an object of the present invention to provide a photoresist stripping composition capable of producing highly accurate circuit wiring that is difficult to produce.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to achieve the above-mentioned object, and as a result, a photoresist stripping composition containing an amine compound and an amine polymer was found to remain as a photoresist. The present inventors have completed the present invention by discovering that residues and the like can be easily peeled off in a short time, at that time, various materials are not corroded and that they have excellent properties.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is a composition for removing a photoresist from a substrate, which is a photoresist stripping composition comprising an amine compound and an amine polymer. Further, the resist stripping composition containing an amine compound, an amine polymer and water can be used to more effectively strip the resist.

The amine polymer used in the present invention may have a weight average molecular weight of 250 or more, the nitrogen atom has a side chain,
It may be contained in either main chain. There is no particular limitation on the one having a large molecular weight, but if it is too large, it becomes difficult to mix with the amine. The amine polymer may be either a free type or a salt type and can be used depending on the purpose, and is preferably a free type or an organic acid salt type.

Specific examples of the amine polymer include polyethyleneimine, polyvinylamine, polyallylamine, polyornithine, polylysine, polyallyl biguanide allylamine, polyallyl-N-carbamoylguanidinoallylamine, polyallylamine copolymer, polydiallylamine, polydiallylamine copolymer. Examples include coalescing. The present invention is not limited to this example as long as it is an amine polymer. The amine polymer may use 1 type (s) or 2 or more types. Preferably, polyethyleneimine, polyvinylamine and polyallylamine are easily available and easy to use. The structural formula of this polymer is shown below, which is a schematic one.

[0008]

[Chemical 1]

In the present invention, the amine polymer is not limited to the above compounds and may be any polymer having a structure containing an amino group. The amino group is effective regardless of the form of primary, secondary, tertiary and quaternary. Also, they may be mixed. For example, commercially available polyethyleneimine (Nippon Shokubai) is a mixed type of 35% primary, 35% secondary, and 30% tertiary, but can work effectively.

Usually, amine compounds often corrode silicon, but amine polymers can prevent corrosion. The mechanism is expected as follows. It is considered that when silicon corrodes, it elutes as a silicate ion or amine compound coordinator. At this time, it is considered that the presence of the amine polymer causes the amine polymer to coordinate on the surface before the elution, or to form a passive film as a counter cation, thereby suppressing the elution. The amine polymer not only suppresses the corrosion of silicon, but also has the effect of suppressing the corrosion of other wiring materials. In particular, it can also work effectively on aluminum and aluminum alloys.

Examples of the amine compound used in the present invention include alkylamine, alkanolamine, polyamine, hydroxylamine, cyclic amine and quaternary ammonium. Specific examples of the alkylamine include methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, sec-butylamine,
Isobutylamine, t-butylamine, pentylamine, 2-aminopentane, 3-aminopentane, 1-amino-2-methylbutane, 2-amino-2-methylbutane, 3-
Amino-2-methylbutane, 4-amino-2-methylbutane, hexylamine, 5-amino-2-methylpentane,
Primary alkylamines such as heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, dimethylamine, diethylamine , Dipropylamine, diisopropylamine, dibutylamine, diisobutylamine, di-
sec-butylamine, di-t-butylamine, dipentylamine, dihexylamine, diheptylamine, dioctylamine, dinonylamine, didecylamine, methylethylamine, methylpropylamine, methylisopropylamine, methylbutylamine, methylisobutylamine, methyl-sec-butylamine , Methyl-t-butylamine, methylamylamine, methylisoamylamine, ethylpropylamine, ethylisopropylamine, ethylbutylamine, ethylisobutylamine, ethyl-sec-butylamine, ethylamine, ethylisoamylamine, propylbutylamine, propylisobutylamine, etc. Secondary alkyl amine, trimethyl amine, triethyl amine, tripropyl amine, tributyl amine, tripentyl amine Min, dimethylethylamine, methyldiethylamine, methyldipropylamine,
Examples thereof include tertiary alkylamines such as N-ethylidenemethylamine, N-ethylideneethylamine, N-ethylidenepropylamine and N-ethylidenebutylamine.

Specific examples of the alkanolamine include ethanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine,
N-butyethanolamine, diethanolamine, isopropanolamine, N-methylisopropanolamine, N-ethylisopropanolamine, N-propylisopropanolamine, 2-aminopropane-1-ol,
N-methyl-2-amino-propane-1-ol, N-ethyl-
2-amino-propane-1-ol, 1-aminopropane-3-
Or, N-methyl-1-aminopropane-3-ol, N-ethyl-1-aminopropane-3-ol, 1-aminobutane-
2-ol, N-methyl-1-aminobutane-2-ol, N-
Ethyl-1-aminobutane-2ol, 2-aminobutane-1
-Ol, N-methyl-2-aminobutane-1-ol, N-ethyl-2-aminobutane-1-ol, 3-aminobutane-1-
Or, N-methyl-3-aminobutane-1-ol, N-ethyl-3-aminobutane-1-ol, 1-aminobutane-4-ol
-L, N-methyl 1-aminobutane-4-ol, N-ethyl-
1-aminobutane-4-ol, 1-amino-2-methylpropane-2-ol, 2-amino-2-methylpropane-1-ol
1, 1-aminopentane-4-ol, 2-amino-4-methylpentane-1-ol, 2-aminohexane-1-ol,
3-aminoheptane-4-ol, 1-aminooctane-2-
Or, 5-aminooctane-4-ol, 1-aminopupan
-2,3-Diol, 2-aminopropane-1,3-dio-
, Tris (oxymethyl) aminomethane, 1,2-diaminopropane-3-ol, 1,3-diaminopropane-
2-ol, 2- (2-aminoethoxy) ethanol, N-ethylideneethanolamine, N-ethylideneethoxyethanolamine, N-hydroxymethylethanolamine,
N-hydroxymethylethylenediamine N, N'-bis (hydroxymethyl) ethylenediamine, N-hydroxymethylpropanolamine and the like can be mentioned.

As the polyamine, ethylenediamine,
Propylenediamine, trimethylenediamine, tetramethylenediamine, 1,3-diaminobutane, 2,3-diaminobutane, pentamethylenediamine, 2,4-diaminopentane, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylene Diamine, N-methylethylenediamine, N, N-dimethylethylenediamine, trimethylethylenediamine, N-ethylethylenediamine, N, N-diethylethylenediamine, triethylethylenediamine, 1,2,3-triaminopropane, hydrazine, tris (2-aminoethyl) ) Amine, tetra (aminomethyl) methane, diethylenetriamine, triethylenetetramine, tetraethylpentamine, heptaethyleneoctamine, nonaethylenedecamine, diazabicyclo Examples include undecene, polyethyleneimine, polyvinylamine, polyallylamine and the like.

Examples of hydroxylamine include hydroxylamine, N-methylhydroxylamine, N-ethylhydroxylamine and N, N-diethylhydroxylamine.

Specific examples of the cyclic amine include pyrrole, 2-methylpyrrole, 3-methylpyrrole, 2-ethylpyrrole, 3-ethylpyrrole, 2,3-dimethylpyrrole, 2,4 dimethylpyrrole and 3,4. 4-dimethylpyrrole, 2,3,4-trimethylpyrrole, 2,3,5-trimethylpyrrole, 2-pyrroline, 3-pyrroline, pyrrolidine, 2-methylpyrrolidine, 3-methylpyrrolidine, pyrazol, imidazole , 1,2,3-triazole, 1,
2,3,4-tetrazole, piperidine, 2-pipecoline, 3-pipecoline, 4-pipecoline, 2-4 lupetidine, 2,6-lupetidine, 3,5-lupetidine, piperazine, 2-methylpiperazine, 2, Examples thereof include 5-dimethylpiperazine, 2,6-methylpiperazine and morpholine.

Examples of the quaternary ammonium include tetramethylammonium hydroxysite, tetraethylammonium hydroxysite, tetrapropylammonium hydroxysite, tetrabutylammonium hydroxysite, choline hydroxysite, acetylcholine hydroxysite and the like.

The amine used in the present invention is not limited to the above amines and is not limited as long as it is an amine compound.

Among the above amines, especially, methylamine, ethylamine, propylamine, butylamine, ethanolamine, N-methylethanolamine, N-ethylethanolamine, diethanolamine, isopropanolamine, 2- (2-aminoethoxy). Ethanol, ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, piperazine and morpholine are preferred.

The amine polymer used in the present invention is also one kind of amine compound, and the amine polymer can be used as the amine compound. In this case, only the amine polymer can be used. These amine compounds may be used alone or in combination of two or more.

The organic solvent used in the present invention is not particularly limited as long as it is miscible with the mixture of the above-mentioned amine polymer and amine compound. It is preferably a water-soluble organic solvent. Specific examples include ethylene glycol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene. Glycolic monoethyl ether
-Ter, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, etc. -Ter series solvent, formamide, monomethylformamide, dimethylformamide, monoethylformamide, diethylformamide, acetamide, monomethylacetamide, dimethylacetamide, monoethylacetamide,
Amide solvents such as diethylacetamide, N-methylpyrrolidone and N-ethylpyrrolidone, methyl alcohol, ethyl alcohol, isopropanol, ethylene glycol
Alcohols such as propylene glycol and propylene glycol, sulfoxide solvents such as dimethyl sulfoxide, sulfone solvents such as dimethyl sulfone, diethyl sulfone and tetramethylene sulfone, 1,3-dimethyl-2-imidazolidinone, 1 Examples thereof include imidazolidinone-based solvents such as 3,3-diethyl-2-imidazolidinone and 1,3-diisopropyl-2-imidazolidinone, and lactone solvents such as γ-butyrolactone and δ-valerolactone. Further, amine oxide solvents such as trimethylamine oxide and methylmorpholine oxide can be used. Among these, dimethyl sulfoxide, N, N-dimethylformald, N,
N-dimethylacetamide, N-methylpyrrolidone, diethylene glycol monomethyl ether, diethylene glyco
-Rumonobutyl ether, dipropylene glycol-monomethyl ether, dipropylene glycol-monobutyl ether and propylene glycol are easily available and have a high boiling point and are easy to use.

In the resist stripping composition of the present invention, an anticorrosive agent can be used if necessary. Examples of the type of anticorrosive agent include phosphoric acid-based, carboxylic acid-based, amine-based, oxime-based, aromatic hydroxy compounds, triazole compounds and sugar alcohols. Among these, the anticorrosive is an aromatic hydroxy compound,
Sugar alcohol compounds and triazole compounds are common and easy to use. Specific examples of the anticorrosive agent include 1,2-propanediaminetetramethylenephosphonic acid, phosphoric acid such as hydroxyethanephosphonic acid, ethylenediaminetetraacetic acid, dihydroxyethylglycine, nitrilotriacetic acid, oxalic acid, citric acid, and apple. Acid, carboxylic acid such as tartaric acid, bipyridine, tetraphenylporphyrin, phenanthroline, amine such as 2,3-pyridinediol, oxime such as dimethylglyoxime, diphenylglyoxime, phenylacetylene,
An acetylene-based anticorrosive such as 2,5-dimethyl-3-hexyne-2,5-diol can be used.

Specific examples of the aromatic hydroxy compound include phenol, cresol, xylenol, and pyrocateco.
, T-butylcatechol, resorcinol, hydroquinone, pyrogallol, 1,2,4-benzenetriol,
Salicyl alcohol, p-hydroxybenzyl alcohol
, O-hydroxybenzyl alcohol, p-hydroxyphenethyl alcohol, p-aminophenol, m-aminophenol, diaminophenol, aminoresorcinol, p-hydroxybenzoic acid, o-hydroxybenzoic acid, 2,4- Examples thereof include dihydrobenzoic acid, 2,5-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid and gallic acid. Sugar Arco-
Examples of the solvent include sorbitol, xylitol, palatinit and the like. In addition, trizole compounds such as benzotriazole, aminotriazole, and aminotetrazole are listed as anticorrosion agents. These compounds can be used alone or in combination of two or more.

In the present invention, the amine compound is used in the range of 0.1 to 95% by weight, the amine polymer concentration is 0.0001 to 95% by weight, and the organic solvent is 0 to 99% by weight. The amount of the organic solvent used is not particularly limited, but the concentration may be appropriately determined in consideration of the viscosity, specific gravity or etching of the composition, ashing conditions and the like. The amount of the anticorrosive added to the composition of the present invention is not particularly limited, but it is 0 to 30% by weight, preferably 15% by weight or less. The use of water in the present invention is not particularly limited, but the concentration may be determined in consideration of etching and ashing conditions. It is usually used in the range of 0 to 50% by weight. In the absence of any water, the etching of silicon is often very small and the amine polymer function is ineffective. However, in many semiconductor processes, rinsing with water is often performed after the resist is stripped, and at that time, a state of being mixed with water is created. Therefore, the photoresist stripping solution containing an amine polymer has an advantage that it does not corrode when mixed with water.

The temperature for stripping the resist using the photoresist stripping solution of the present invention is usually room temperature to 150 ° C.
However, the peeling can be carried out at a low temperature of 70 ° C. or lower, and it is preferable to carry out the peeling at a temperature as low as possible in consideration of the attack on the material.

The substrate material used in the present invention is silicon,
Amorphous silicon, polysilicon, silicon oxide film, silicon nitride film, copper and copper alloys, aluminum, aluminum alloys, gold, platinum, silver, titanium, titanium-tungsten, titanium nitride, tungsten, tantalum, tantalum compounds, chromium, Semiconductor wiring materials such as chromium oxide, chromium alloy, ITO (indium-tin oxide), compound semiconductors such as gallium-arsenic, gallium-phosphorus and indium-phosphorus, dielectric materials such as strontium-bismuth-tantalum, and LCD The glass substrate and the like are used.
Particularly effective are substrates containing bare silicon, amorphous silicon, and polysilicon.

In the method for manufacturing a semiconductor device of the present invention, after removing an unnecessary portion of a film formed of a resist by etching with a predetermined pattern, the resist is removed by the above-mentioned stripping solution. If desired, ashing treatment can be performed, and then the residue generated by etching can be removed by the above-described stripping solution. Here, the ashing process (ashing) means, for example, that a resist made of an organic polymer is burned by oxygen plasma generated in the plasma to generate C
It is to be removed as O and CO2.

As a rinsing method after using the photoresist stripping solution of the present invention, an organic solvent such as alcohol may be used, or rinsing may be performed with water, and there is no particular limitation. .

[0028]

EXAMPLES The present invention will be described in detail with reference to examples. However, the present invention is not limited to these examples.

Examples 1 to 7 and Comparative Examples 1 and 2 In this example, amorphous silicon (aS
The glass substrate on which i) was formed was coated with a resist and then developed. After that, a circuit was formed through a dry etching process. Using this substrate, the resist peeling property was tested. Also, amorphous silicon etching
Also measured. The above substrate was immersed in a stripping solution having the composition shown in Table 1 at 40 ° C. After a predetermined time, the substrate was taken out, rinsed with water, blown with a nitrogen gas, dried, and observed with an optical microscope. The time required for resist stripping was measured. Before measuring the etching rate of amorphous silicon, the oxide layer was removed with buffered hydrofluoric acid before processing. The etching rate of amorphous silicon was obtained by using an optical film thickness meter. Table 1 shows the results.

[0030]

[Table 1]

Examples 8 to 14 and Comparative Examples 3 and 4 In order to manufacture a semiconductor device, dry etching is performed using a resist film as a mask to form an Al alloy (Al-Cu) wiring body 5, and then ash is formed by oxygen plasma. FIG. 1 shows a cross-sectional view of a part of the semiconductor device which has been subjected to the chemical conversion treatment. In the semiconductor device, an oxide film 2 is formed on a silicon substrate 1, an Al alloy 5 which is a wiring body is formed on the oxide film 2, and a resist residue 6 remains on the side wall. Note that titanium 3 and titanium nitride 4 are present as barrier metals. The semiconductor device shown in FIG. 1 was immersed in a stripping solution having the composition shown in Table 2 at 70 ° C. for 15 minutes, rinsed with ultrapure water, dried, and observed with an electron microscope (SEM). Table 2 shows the results of evaluation of the peeled state of the resist residue 6 and the corroded state of the aluminum wiring body 5. The evaluation criteria by SEM observation are as follows. A: It was completely removed. B: Residue was observed. C: Corrosion was observed. The bare silicon etching rate of the composition used in this experiment was also measured at 70 ° C.

[0032]

[Table 2]

Examples 15 to 20 and Comparative Examples 5 and 6 In this example, the resist on the glass substrate having the structure of low temperature polysilicon (p-Si) on SiO ₂ is removed to form a thin film transistor. The test was conducted. FIG. 2 shows a cross-sectional view of the exposed polysilicon portion of the test substrate. On the glass substrate 11
Low-temperature polysilicon 9 is formed with SiO ₂ 10 sandwiched therebetween. There is an insulating layer 7 on it, and a resist 8 remains on this. There is a portion without an insulating layer, and there is a portion that comes into direct contact with the resist stripping solution. The resist strippability was tested. The etching rate of polysilicon was also measured. The above substrate was immersed in a stripping solution having the composition shown in Table 3 at 40 ° C. After a predetermined time, the substrate was taken out, rinsed with water, blown with a nitrogen gas, dried, and observed with an optical microscope.
The time required for resist stripping was measured. Before measuring the etching rate of polysilicon, the oxide layer was removed with buffered hydrofluoric acid before processing. Etching of polysilicon
-G was determined using an optical film thickness meter. The results are shown in Table 3.

[0034]

[Table 3]

[0035]

By using the photoresist stripping solution of the present invention, resist stripping can be performed in a short time. Furthermore, it can be peeled off without corroding the wiring material or the like, especially without corroding silicon. More specifically,
The photoresist stripping solution of the present invention can effectively suppress corrosion without distinguishing between bare silicon, amorphous, and polysilicon, and can strip a photoresist from a substrate containing silicon without corrosion.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a part of a semiconductor device that has been ashed by oxygen plasma.

FIG. 2 is a sectional view of an exposed polysilicon portion of a test substrate.

[Explanation of symbols]

1 silicon substrate, 2 oxide film, 3 titanium, 4 titanium nitride,
5 Al alloy, 6 resist residue, 7 insulating layer, 8 resist,
9 polysilicon, 10 SiO ₂ , 11 glass

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Yoshida             6-1, 1-1 Shinjuku, Katsushika-ku, Tokyo Mitsubishi tile             The Chemical Research Institute Tokyo Research Center F-term (reference) 2H096 AA25 AA26 AA27 LA03                 5F043 AA40 CC16 GG10                 5F046 MA02

Claims (9)

[Claims] 1. A photoresist stripping composition comprising an amine compound and an amine polymer. 2. A photoresist stripping composition comprising an amine compound, an amine polymer and water. 3. The amine polymer is polyethyleneimine,
The photoresist stripping composition according to claim 1 or 2, which is polyvinylamine or polyallylamine. 4. The weight average molecular weight of the amine polymer is 250.
The photoresist stripping composition according to any one of claims 1 to 3 above. 5. The photoresist stripper composition according to claim 1, wherein the amine compound is alkylamine, alkanolamine, polyamine, hydroxylamine, cyclic amine or quaternary ammonium. 6. The photoresist stripper composition according to claim 1, further comprising an organic solvent. 7. The photoresist stripper composition according to claim 1, further comprising an anticorrosive agent. 8. The anticorrosive agent is an aromatic hydroxy compound, a sugar alcohol compound or a triazol compound.
The photoresist stripping composition described. 9. A method of manufacturing a semiconductor device, comprising using the photoresist stripping composition of claim 1 or 2 to strip the resist from a substrate containing silicon.