JP3476367B2 - Resist stripping composition and resist stripping method using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resist stripping composition and a resist stripping method using the same. More specifically, a resist stripping composition for use in the production of semiconductor devices such as ICs and LSIs or liquid crystal panel devices, which has excellent releasability of a resist film and excellent storage stability at high temperatures, and the same. The present invention relates to a resist stripping method using.

[0002]

2. Description of the Related Art For semiconductor elements such as ICs and LSIs and liquid crystal panel elements, a photoresist is uniformly applied to a conductive metal film such as a NES film formed on a substrate by vapor deposition or an insulating film such as a SiO ₂ film. Then, this is selectively exposed and developed to form a resist pattern, and the conductive metal film or insulating film is selectively etched using this pattern as a mask,
After forming a fine circuit, an unnecessary resist layer is removed with a stripping solution to manufacture.

As a stripping solution for removing this resist layer,
Conventionally, an organic sulfonic acid-based stripping solution containing an alkylbenzene sulfonic acid as an essential component and an organic amine-based stripping solution containing an organic amine such as monoethanolamine as an essential component have been used. The former organic sulfonic acid-based stripping solution has poor workability because it is used in combination with highly toxic organic compounds such as phenolic compounds and chlorobenzene, and also causes environmental problems and corrodes the conductive metal film of the substrate. It has the drawback that it is easy to get rid of. On the other hand, the latter organic amine-based stripping solution is less toxic than the organic sulfonic acid-based stripping solution, does not require complicated treatment for waste liquid treatment, and has the effect of preventing corrosion of substrates containing Al, Cu, etc. It is widely used today because of its superiority.

In the organic amine-based stripping solution treatment, the stripping solution in the stripping solution tank is treated at a relatively high temperature of 60 to 80, for example.
A dipping method in which the substrate is heated to about 0 ° C. and immersed in the heated stripping solution to perform stripping, a shower method in which the stripping solution heated to the above temperature is sprayed onto the substrate, and the like are used. In such a stripping treatment, a stripping solution of 60 to 8 is used.
Even if it is kept at a high temperature of 0 ° C. for a long time, its characteristics (peelability, corrosion resistance) should not be impaired. In particular, a large glass substrate used for a liquid crystal panel element or the like has a size of, for example, 360 mm × 460 mm, 550 m, as compared with a substrate for a semiconductor integrated circuit which is said to have a diameter of 300 mm at the maximum.
A considerably large size such as m × 650 mm, 600 mm × 720 mm is used. Therefore, the stripping solution tank also becomes large in proportion to the size of the substrate, so that the stripping solution easily evaporates and its composition easily changes.

Conventionally, as a stripping composition for resist,
For example, alkanolamines, alkoxyalkylamines or alkoxyalkanolamines, glycol monoalkyl ethers, sugars or sugar alcohols,
And a resist stripper composition comprising water (Japanese Patent Laid-Open No. 8-1
90205), alkanolamines, alkoxyalkylamines or alkoxyalkanolamines, acid amides, sugars or sugar alcohols, and water (JP-A-8-20205).
No. 1), alkanolamines, alkoxyalkylamines or alkoxyalkanolamines, glycol monoalkyl ethers, sugars or sugar alcohols, quaternary ammonium hydroxides, and water. No. 8-262746), alkanolamines, alkoxyamines or alkoxyalkanolamines, hydroxylamines, sugars or sugar alcohols, surfactants, and water (JP-A-9-54442).
Gazette), alkanolamines, diethylene glycol monoalkyl ethers, sugars or sugar alcohols,
Stripping solution composition for resist consisting of N, N-diethylhydroxylamine and water (JP-A-9-152721), amines having pKa of 7.5 to 13, hydroxylamines, water-soluble organic solvent, anticorrosive agent And a resist stripping composition for resist (Japanese Patent Laid-Open No. 9-96911).

The compositions described in the above-mentioned respective publications are mainly intended for peeling off a photoresist-altered film or a metal deposition film formed after an ashing process.

Among the compositions described in each of the above publications, JP-A-8
-190205, JP-A-8-202051, JP-A-8-262746, JP-A-9-969.
Although the composition described in JP-A No. 11 shows almost satisfactory releasability with respect to a resist-altered film, it does not necessarily exhibit sufficient releasability with respect to an unaltered resist film. Has not arrived.

Japanese Unexamined Patent Publication No. 9-54442 and Japanese Unexamined Patent Publication No. 9-
In the composition disclosed in Japanese Patent No. 152721, when the water content is too high, the substrate is likely to be corroded, while when the water content is too low, the flash point is lowered and the work risk may be increased. Furthermore, since water is also the only component that dissolves sugars or sugar alcohols, the stripping solution composition is used when the water content is low or when the water content is moderate and the material is used at a high temperature for a long time. Layer separation can occur between the sugar or sugar alcohol layers and the other ingredient layers therein.

[0009]

The present invention is particularly excellent in the releasability of a resist layer that has not deteriorated, and
An object of the present invention is to provide a resist stripping composition having excellent storage stability at high temperatures and a resist stripping method using the same.

[0010]

Means for Solving the Problems That is, the present invention is
(A) Alkanolamines, (b) N, N-diethylhydroxylamine, (c) saccharides, (d) N-methyl-
2-pyrrolidone, any one or more selected from among di-methyl sulfoxide, and (e) a resist stripping solution composition comprising water.

In the present invention, (I) a step of forming a resist layer on a substrate, (II) a step of selectively exposing the resist layer, and (III) developing the exposed resist layer to form a resist pattern. In the resist stripping method comprising the steps of: (IV) etching the substrate using the resist pattern as a mask; and (V) stripping the etched resist pattern from the substrate, the resist stripping composition is used. The present invention relates to a resist stripping method, which strips a resist pattern after etching.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The stripping solution composition for resist of the present invention is described in detail below.

Specific examples of the alkanolamines as the component (a) include monoethanolamine, diethanolamine, triethanolamine, ethylaminoethanol, dimethylaminoethanol, diethylaminoethanol and 2- (2-aminoethoxy) ethanol. Etc. Among them, monoethanolamine, diethanolamine, and 2-2 (aminoethoxy) ethanol are preferably used. These may be used alone or in combination of two or more.

In the stripper composition of the present invention, the upper limit of the amount of the component (a) to be blended is preferably 40% by weight, and particularly preferably 30% by weight. The lower limit is preferably 5% by weight, particularly 10
Weight percent is preferred.

N, N-diethylhydroxylamine as the component (b) is a compound represented by N (C ₂ H ₅ ) ₂ OH.

In the stripper composition of the present invention, the upper limit of the amount of the component (b) compounded is preferably 30% by weight, particularly preferably 20% by weight. The lower limit is preferably 5% by weight, particularly 10
Weight percent is preferred.

As the saccharide as the component (c), C is generally
So-called sugars represented by _n (H ₂ O) _m , sugar alcohols obtained by reducing the carbonyl groups of these sugars, and the like are used, and specifically, D-sorbitol, arabitol, mannitol, xylitol, sucrose, Examples of the starch include xylitol and D-sorbitol. These may be used alone or in combination of two or more.

In the stripper composition of the present invention, the upper limit of the amount of component (c) to be blended is preferably 30% by weight, and particularly preferably 25% by weight. The lower limit is preferably 2% by weight, particularly 5% by weight.

As the component (d), N-methyl-2-
Pyrrolidone, di-methyl sulfoxide, or a mixed solvent thereof, are used.

In the stripper composition of the present invention, the upper limit of the amount of the component (d) to be blended is preferably 40% by weight, particularly 30% by weight. The lower limit is preferably 5% by weight, particularly 10
Weight percent is preferred.

Water as the component (e) is inevitably contained in the component (a) and the like, but the amount thereof may be adjusted in addition. The blending ratio of the component (e) is the balance of the blending amounts of the components (a) to (d) in the stripper composition of the present invention.

In the present invention, by making the components (a) to (e) within the above-mentioned blending ratio range, more excellent effects can be achieved in terms of releasability, storage characteristics at high temperatures, and anticorrosion properties.

The resist stripping composition of the present invention can be advantageously used for resists that can be developed with an aqueous alkaline solution, including negative and positive resists. Examples of such a resist include (i) a positive resist containing a naphthoquinonediazide compound and a novolak resin, (ii) a compound that generates an acid upon exposure to light, a compound that decomposes with an acid to increase its solubility in an alkaline aqueous solution, and an alkali-soluble compound. A positive resist containing a resin, (iii) a compound that generates an acid upon exposure to light, a positive resist containing an alkali-soluble resin having a group that decomposes by an acid to increase solubility in an aqueous alkaline solution, and (iv) by light Examples thereof include, but are not limited to, a negative resist containing a compound that generates an acid, a crosslinking agent, and an alkali-soluble resin.

The resist stripping method of the present invention comprises (I) a step of providing a resist layer on a substrate, (II) a step of selectively exposing the resist layer, and (III) developing the resist layer after exposure to form a resist. A resist stripping composition comprising the steps of: providing a pattern; (IV) etching the substrate using the resist pattern as a mask; and (V) stripping the etched resist pattern from the substrate. Is used to peel off the resist pattern after etching.

Examples of the substrate include a substrate having a metal layer formed thereon. As the metal layer, aluminum (A
l); Aluminum alloys (Al alloys) such as aluminum-silicon (Al-Si) and aluminum-silicon-copper (Al-Si-Cu); pure titanium (Ti); titanium nitride (TiN), titanium tungsten (TiW). ) And other titanium alloys (Ti alloys) and the like, but are not limited to these.

The coating, drying, exposing, developing and etching treatments are all conventional means and are not particularly limited. Either wet etching or dry etching can be used as the etching, but the stripping composition of the present invention can be particularly preferably used for stripping the resist film after the wet etching. Particularly in a glass substrate or the like used for a liquid crystal panel element or the like, an acidic etching liquid such as phosphoric acid, nitric acid or acetic acid is preferably used as an etching liquid (etchant).

The developing step (III), (V)
After the stripping step, a rinsing treatment and a drying treatment using pure water, lower alcohol, or the like, which are conventionally performed, may be performed.

The peeling treatment is usually performed by a dipping method or a shower method. The peeling time is not particularly limited as long as it is a sufficient peeling time. In addition, the temperature of the stripping solution at that time is high in the corrosion preventing effect on the metal film even at a high temperature of 60 to 80 ° C. in the stripping method using the stripping solution composition of the present invention, and the resist film not particularly denatured It has excellent releasability. The stripper composition of the present invention has a viscosity of 60 to
It has excellent storage stability even at a high temperature of 80 ° C., does not change in composition, and can be reused. Therefore, it has effects such as reduction of manufacturing cost.

[0029]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

(Examples 1 to 5 and Comparative Examples 1 to 7) THMR-iP3300 (Tokyo Ohka Kogyo Co., Ltd.), which is a positive photoresist composed of a naphthoquinonediazide compound and a novolac resin, is formed on a substrate having Al wiring formed on a silicon wafer. Co., Ltd.) was applied with a spinner and prebaked at 90 ° C. for 90 seconds to form a resist layer having a film thickness of 2.0 μm. This resist layer is NSR-2005i10D
(Nikon Corp.) was used for exposure through a mask pattern, followed by development with a 2.38 wt% tetramethylammonium hydroxide (TMAH) aqueous solution to form a resist pattern. Then, post baking was performed at 120 ° C. for 90 seconds.

[Resistant film releasability test] Next, the silicon wafer having a resist pattern formed under the above conditions is wet-etched with a mixed acid type etchant of phosphoric acid, nitric acid, and acetic acid, and then with pure water. Washed.

A resist film peeling treatment was carried out by spraying a stripping solution composition of each composition shown in Table 1 (held at 60 ° C.) onto the treated substrate by a shower method. The substrate after the peeling treatment was sufficiently rinsed with pure water, and the peelability of the resist film at this time was evaluated by observing SEM (scanning electron microscope) photographs. The results are shown in Table 2.

The releasability of the resist film was evaluated as follows.

A: The resist film is completely peeled off B: The residue of the resist film remains

[Storage Stability Under Heating] Further, in order to evaluate the storage stability under heating, the stripping solution having the composition shown in Table 1 was heated to 60 ° C. and maintained at that temperature. The state of the solution at this time was observed and evaluated. The results are shown in Table 2.

The state of the stripping solution was evaluated as follows.

A: No change was observed in the solution after 48 hours or more. B: The solution separated into two layers after 12 hours.

[0038]

[Table 1]

In Table 1, MEA is monoethanolamine; AEE is 2- (2-aminoethoxy) ethanol; TET is triethylenetetramine; NMP is N-methyl-2-pyrrolidone; DMSO is diethylenediamine. DEMB is diethylene glycol monobutyl ether; DEMM is diethylene glycol monomethyl ether; TMAH is tetramethylammonium hydroxide; HA is hydroxylamine; PG
MOPE represents propylene glycol mono-P-octyl phenyl ether, respectively.

[0040]

[Table 2]

[0041]

As described above in detail, according to the present invention, there is provided a resist stripping composition which is excellent in stripping property of a resist layer and storage stability at high temperature, and a resist stripping method using the same. To be done. The present invention is particularly preferably used for peeling a resist layer formed on a large-sized substrate used for manufacturing a liquid crystal panel element or the like. According to the present invention, the composition of the stripping solution does not change even in stripping treatment at high temperature, the stripping solution can be circulated and used, and the manufacturing cost can be reduced.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-9-54442 (JP, A) JP-A-9-152721 (JP, A) JP-A-7-271057 (JP, A) JP-A-8- 202051 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G03F ^7/ 00-7/42 H01L 21/027

Claims (4)

(57) [Claims] 1. (a) Alkanolamines, (b)
N, N-diethylhydroxylamine, (c) sugar,
(D) N-methyl-2-pyrrolidone, any one or more selected from among di-methyl sulfoxide, and (e)
A resist stripping composition comprising water. 2. The resist stripping composition according to claim 1, wherein the component (a) is at least one selected from monoethanolamine, diethanolamine and 2- (2-aminoethoxy) ethanol. 3. The component (a) is 5 to 40% by weight, the component (b) is 5 to 30% by weight, the component (c) is 2 to 30% by weight,
The resist stripper composition according to claim 1 or 2, wherein the component (d) is blended in an amount of 5 to 40% by weight, and the balance is the component (e). 4. (I) providing a resist layer on the substrate, (II) selectively exposing the resist layer,
From (III) a step of developing a resist layer after exposure to provide a resist pattern, (IV) a step of etching the substrate using the resist pattern as a mask, and (V) a step of peeling the resist pattern after etching from the substrate In the resist stripping method, the resist stripping composition according to any one of claims 1 to 3 is used to strip the resist pattern after etching.