WO2011031028A2

WO2011031028A2 - Resist stripper composition for forming copper-based wiring

Info

Publication number: WO2011031028A2
Application number: PCT/KR2010/005854
Authority: WO
Inventors: Hun-Pyo Hong; Hyung-Pyo Hong; Tae-Hee Kim; Seung-Yong Lee; Byoung-Mook Kim
Original assignee: Dongwoo Fine-Chem Co., Ltd.
Priority date: 2009-09-09
Filing date: 2010-09-09
Publication date: 2011-03-17
Also published as: WO2011031028A3; JP2013504782A; TW201120587A; CN102483590B; CN102483590A; TWI516879B

Abstract

Disclosed is a resist stripper composition for forming copper-based wiring, which uses a compound containing sulfone and/or sulfine and/or an ester as the stripper and which can effectively prevent the corrosion of a conductive metal layer of copper or copper alloy wiring and an insulating layer of silicon oxide or silicon nitride which are disposed under the resist, even without the use of isopropanol as an intermediate cleaner, and also can cleanly remove the deteriorated and/or cured resist even at low temperature in a short period of time.

Description

RESIST STRIPPER COMPOSITION FOR FORMING COPPER-BASED WIRING

The present invention relates to a resist stripper composition for forming copper (Cu)-based wiring, which is used in the course of manufacturing a semiconductor device or a flat panel display, and more particularly to a resist stripper composition which is able to prevent a Cu layer serving as wiring from corroding upon removing a resist.

Forming integrated circuits of semiconductor devices or micro circuits of flat panel displays is carried out by uniformly applying a photoresist on a conductive metal layer of aluminum (Al), Al alloy, Cu or Cu alloy, or an insulating layer of silicon oxide or silicon nitride, formed on a substrate, and performing selective photo-exposure and development, thus forming a photoresist pattern. Subsequently, wet or dry etching the conductive metal layer or the insulating layer using the photoresist pattern as a mask so that a micro circuit pattern is transferred to the layer under the photoresist and then removing the unnecessary photoresist using a stripper composition are performed.

The stripper composition for removing the photoresist used in the course of manufacturing the semiconductor device or the flat panel display should be able to strip the photoresist at low temperature in a short period of time, should prevent the photoresist residue from remaining on the substrate after rinsing, and should not damage the metal layer or the insulating layer under the photoresist.

Meanwhile, a Cu-based metal layer including a Cu layer and a Cu-molybdenum (Mo) layer is recently receiving attention as the metal layer to be used for forming metal wiring in the field of semiconductor devices or flat panel displays. In the case of thin film transistor-liquid crystal displays (TFT-LCDs), because resistance is a main factor when it comes to inducing RC signal delay, solving RC signal delay problems is the key to increasing the size of a panel and achieving high resolution.

However, photoresist stripper compositions developed to date which use amine compounds or glycol ether compounds as the stripper are disadvantageous because they severely corrode the Cu-based metal layer, may cause environmental problems due to high toxicity, or generate higher defect rates in a subsequent process of depositing a gate insulating layer. Hence, such problems are required to be solved.

Accordingly, the present invention is intended to provide a resist stripper composition for forming Cu-based wiring, which is capable of effectively preventing a conductive metal layer of Cu or Cu alloy wiring and an insulating layer of silicon oxide or silicon nitride under a resist from corroding, even without intermediate cleaning using isopropanol.

Also the present invention is intended to provide a resist stripper composition for forming Cu-based wiring, which may be applied to all of the dipping type, single sheet type and spraying type stripping processes and is capable of cleanly removing a resist, which deteriorated and/or was cured by severe lithography processing and wet etching processing, at low temperature in a short period of time.

An aspect of the present invention provides a resist stripper composition for forming Cu-based wiring, comprising, based on the total weight of the composition, A) 1 ~ 45 wt% of one or more compounds selected from among compounds represented by Formulas 1 to 3 below, B) 0.01 ~ 5 wt% of an additive including an azole compound, and C) a remainder of a solvent including a compound represented by Formula 4 below.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4, R₁, R₂, R₃ and R₄ are each independently a C1~6 alkyl group, and R₁ and R₂, or R₃ and R₄ are able to be linked with each other to form a C4~6 ring; R₅ and R₆ are each independently hydrogen, a C1~4 alkyl group, a C1~4 hydroxyalkyl group, a C1~8 alkoxyalkyl group, -R₁₀-(OR₁₁)m-OR₁₂ or -R₁₃-(O)n-(C=O)-(O)o-R₁₄, in which m is a natural number from 1 to 4, n is 0 or 1, o is 0 or 1, R₁₀, R₁₁, R₁₃ and R₁₄ are each independently a C1~5 alkyl group, R₁₂ is hydrogen or a C1~5 alkyl group, and R₅ and R₆ are able to be linked with each other to form a C4~6 ring; and R₇ is hydrogen or a C1~5 alkyl group, R₈ and R₉ are each independently hydrogen, a C1~4 alkyl group or a C1~4 hydroxyalkyl group, and R₇ and R₈ are able to be linked with each other to form a C4~6 ring, wherein the alkyl group is a linear or branched alkyl group.

Another aspect of the present invention provides a method of manufacturing a semiconductor device or a flat panel display using lithography for forming Cu-based wiring, comprising removing a resist after use using the resist stripper composition according to the present invention.

According to the present invention, a resist stripper composition can effectively prevent the corrosion of a conductive metal layer of Cu or Cu alloy wiring and an insulating layer of silicon oxide or silicon nitride, which are formed under a resist, even without the use of isopropanol as an intermediate cleaner. Also, the resist stripper composition can be applied to all of the dipping type, single sheet type and spraying type stripping processes, and is capable of cleanly removing a resist, which deteriorated and/or was cured by severe lithography processing and etching processing, at low temperature in a short period of time. Therefore, the resist stripper composition according to the present invention can be very usefully employed in the fabrication of semiconductor devices or flat panel displays.

The present invention is directed to a resist stripper composition for forming Cu-based wiring, which comprises, based on the total weight of the composition, A) 1 ~ 45 wt% of one or more compounds selected from among compounds represented by Formulas 1 to 3 below, B) 0.01 ~ 5 wt% of an additive including an azole compound, and C) a remainder of a solvent including a compound represented by Formula 4 below.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4, R₁, R₂, R₃ and R₄ are each independently a C1~6 alkyl group, and R₁ and R₂, or R₃ and R₄ may be linked with each other to form a C4~6 ring; R₅ and R₆ are each independently hydrogen, a C1~4 alkyl group, a C1~4 hydroxyalkyl group, a C1~8 alkoxyalkyl group, -R₁₀-(OR₁₁)m-OR₁₂ or -R₁₃-(O)n-(C=O)-(O)o-R₁₄, in which m is a natural number from 1 to 4, n is 0 or 1, o is 0 or 1, R₁₀, R₁₁, R₁₃ and R₁₄ are each independently a C1~5 alkyl group, R₁₂ is hydrogen or a C1~5 alkyl group, and R₅ and R₆ may be linked with each other to form a C4~6 ring; and R₇ is hydrogen or a C1~5 alkyl group, R₈ and R₉ are each independently hydrogen, a C1~4 alkyl group or a C1~4 hydroxyalkyl group, and R₇ and R₈ may be linked with each other to form a C4~6 ring, wherein the alkyl group may be a linear or branched alkyl group.

In the present invention, the Cu-based wiring indicates a wiring formed of a Cu layer or a Cu alloy layer, or a wiring including a Cu layer or a Cu alloy layer, in a semiconductor device or a flat panel display.

In the resist stripper composition according to the present invention, the (A) one or more compounds selected from among compounds represented by Formulas 1 to 3 may be used in an amount of 1 ~ 45 wt%, preferably 30 ~ 40 wt%, based on the total weight of the composition. In the case where the amount of this component falls within the above range, the ability to strip the deteriorated photoresist may become superior, and the corrosion of the conductive metal layer including the Cu layer or the like under the photoresist may be prevented.

Specific examples of the compound represented by Formula 1 or 2 include dimethylsulfoxide, diethylsulfoxide, dimethylsulfone, diethylsulfone, and sulfolane, and specific examples of the compound represented by Formula 3 include dipropyleneglycol methylether acetate, propyleneglycol methylether acetate, γ-butyrolactone, n-butylacetate, ethylbutanoate, and ethyllactate.

In the resist stripper composition according to the present invention, the (B) additive including the azole compound functions to minimize the corrosion of the conductive metal layer and the insulating layer, which are disposed under the resist. Specific examples of the azole compound include tolytriazole, 1,2,3-benzotriazole, 1,2,3-triazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 1-hydroxybenzotriazole, 1-methylbenzotriazole, 2-methylbenzotriazole, benzotriazole-5-carboxylic acid, nitrobenzotriazole, 2-(2H-benzotriazol-2-yl)-4,6-di-t-butylphenol, and adenine, which may be alone or in mixtures of two or more thereof.

Particularly useful is a triazole ring-containing compound. This is because the unshared electron pair of the nitrogen atom of the triazole ring is electronically bound with Cu thus inhibiting the corrosion of metal.

In the general case where cleaning is directly performed using water without the use of isopropanol as an intermediate cleaner, the amine component of the resist stripper composition is mixed with water thus forming alkaline hydroxyl ions having high corrosivity, thereby promoting the corrosion of the conductive metal layer of Cu or Cu alloy. Whereas, the (B) additive including the azole compound may form a complex with the metal layer, in an alkaline state, and thus may be adsorbed to the surface of the layer and may form a protective layer, thereby preventing the corrosion of metal by the hydroxyl ions even without the use of isopropanol.

The (B) additive including the azole compound is used in an amount of 0.01 ~ 5 wt%, preferably 0.1 ~ 3 wt%, based on the total weight of the composition. In the case where the amount of this component falls within the above range, damage to the conductive metal layer and the insulating layer under the resist may be minimized upon removing the resist, and economic benefits may be possible.

In the resist stripper composition according to the present invention, the (C) solvent including the compound represented by Formula 4 includes a compound represented by Formula 4 containing an amide functional group.

[Formula 4]

In Formula 4, R₇ is hydrogen or a C1~5 alkyl group, R₈ and R₉ are each independently hydrogen, a C1~4 alkyl group or a C1~4 hydroxyalkyl group, and R₇ and R₉ may be linked with each other to form a C4~6 ring.

The amide functional group contained in the (C) solvent including the compound represented by Formula 4 functions to increase the ability of a solvent to dissolve a resist composed mainly of a polymer resin and a photoactive compound, compared to when using other conventional solvents. The (C) solvent including the compound represented by Formula 4 may be used in an amount of the remainder so that the total weight of the composition is 100 wt%. In the case where the amount of the solvent falls within the above range, superior stripping performance and anti-galvanic corrosion may result, and economic benefits are produced. Specific examples of the compound represented by Formula 4 include N-methylpyrrolidone, dimethylacetamide, dimethylformamide, N-methylformamide, acetamide, N-methylacetamide, N-(2-hydroxyethyl)acetamide, and 2-pyrrolidone, which may be used alone or in mixtures of two or more thereof.

The resist stripper composition according to the present invention may further comprise (D) water. The (D) water may be deionized water having 18 ㏁/㎝ or more appropriate for semiconductor processes.

The resist stripper composition for forming Cu-based wiring according to the present invention may be applied to all of the dipping type, spraying type and single sheet type stripping processes. Furthermore, the resist which deteriorated and/or was cured by severe lithography processing and wet etching processing may be easily and cleanly removed in a short period of time not only at high temperature but also at low temperature. Moreover, the corrosion of both the conductive metal layer of Cu or Cu alloy wiring and the insulating layer of silicon oxide or silicon nitride, which are disposed under the resist, may be minimized even without the use of isopropanol as an intermediate cleaner.

In addition, the present invention is directed to a method of manufacturing a semiconductor device or a flat panel display using lithography for forming Cu-based wiring, which comprises removing a resist after use using the resist stripper composition according to the present invention.

The following examples which are set forth to illustrate, but are not to be construed to limit the present invention, may provide a better understanding of the present invention.

EXAMPLES 1 ~ 13 and COMPARATIVE EXAMPLES 1 ~ 4: Preparation of Resist Stripper Composition

Resist stripper compositions for forming Cu-based wiring were prepared from components in the amounts shown in Table 1 below.

Table 1

	Stripper		Solvent				Additive
	Kind	Amount(wt%)	Kind	Amount(wt%)	Kind	Amount(wt%)	Kind	Amount(wt%)
Ex.1	Sulfolane	25	NMF	74.5	-	-	TTA	0.5
Ex.2	Sulfolane	35	NMP	24.5	NMF	40	TTA	0.5
Ex.3	Sulfolane	40	DMAC	30	NMP	29.5	Adenine	0.5
Ex.4	DMSO	30	NMF	69	-	-	TTA	1
Ex.5	DMSO	35	NMP	30	NMF	34	BTA	1
Ex.6	DMSO	40	DMAC	30	NMP	29	Adenine	1
Ex.7	DESO	35	NMF	63.5	-	-	TTA	1.5
Ex.8	DPGMEA	35	NMF	64.5	-	-	TTA	0.5
Ex.9	DPGMEA	35	NMP	24.5	NMF	40	TTA	0.5
Ex.10	PGMEA	40	DMAC	30	NMP	29.5	Adenine	0.5
Ex.11	PGMEA	30	NMF	69	-	-	TTA	1
Ex.12	GBL	35	NMP	30	NMF	34	BTA	1
Ex.13	GBL	40	DMAC	29	NMP	30	Adenine	1
C.Ex.1	DGA	15	NMF	84	-	-	TTA	1
C.Ex.2	MEA	30	BDG	70	-	-	-	-
C.Ex.3	DMEA	25	BDG	35	NMP	40	-	-
C.Ex.4	DMEA	25	BDG	35	NMP	39	TTA	1

[Note]

DMSO: dimethylsulfoxide

DESO: diethylsulfoxide

DPGMEA: dipropyleneglycol methylether acetate

PGMEA: propyleneglycol monomethylether acetate

GBL: γ-butyrolactone

DMEA: dimethylethanolamine

MEA: monoethanolamine

DGA: diglycolamine

NMP: N-methylpyrrolidone

BDG: butyldiglycol

DMAC: dimethylacetamide

NMF: N-methylformamide

TTA: tolytriazole

BTA: 1,2,3-benzotriazole

TEST EXAMPLE: Evaluation of Etching Properties

The stripping performance and the degree of corrosion on Cu wiring were evaluated via the following methods using the resist stripper compositions of Examples 1 ~ 13 and Comparative Examples 1 ~ 4.

A single metal layer and a multi-metal layer were applied to a thickness of 200 ~ 500 Å on a glass substrate using a process of forming TFT circuit of LCD, and a Cu layer was then formed thereon to a thickness of 3,000 Å. Thereafter, a positive photoresist was applied and dried, after which photolithography was performed thus forming a pattern, followed by performing wet etching, thereby preparing a test specimen.

(1) Stripping Performance

The resist stripper composition of each of Examples 1 ~ 13 and Comparative Examples 1 ~ 4 was maintained at 40℃, and the test specimen prepared as above was immersed therein for 10 min thus removing the resist pattern. Thereafter, the test specimen was rinsed with deionized water for 60 sec, and dried over nitrogen. After drying completed, how much of the photoresist was stripped from the test specimen was observed using FE-SEM at magnifications of 40,000 ~ 80,000. The results are shown in Table 2 below.

(2) Anticorrosive Performance 1

The resist stripper composition of each of Examples 1 ~ 13 and Comparative Examples 1 ~ 4 was maintained at 60℃, and the test specimen prepared as above was immersed therein for 30 min, rinsed with deionized water for 30 sec, and then dried over nitrogen. After drying completed, the degree of corrosion of the surface, the lateral surface and the cross-section of the test specimen was observed using FE-SEM at magnifications of 40,000 ~ 80,000. The results are shown in Table 2 below.

(3) Anticorrosive Performance 2

The resist stripper composition of each of Examples 1 ~ 13 and Comparative Examples 1 ~ 4 was maintained at 60℃, and the test specimen prepared as above was immersed therein for 10 min. Thereafter, the test specimen was rinsed with deionized water for 30 sec, and dried over nitrogen. This stripping process was continuously performed three times, after which the degree of corrosion of the surface, the lateral surface and the cross-section of the test specimen was observed using FE-SEM at magnifications of 40,000 ~ 80,000. The results are shown in Table 2 below.

※ Evaluation Criteria of Stripping Performance

◎: excellent ○: good

△: fair Х: poor

※ Evaluation Criteria of Anticorrosive Performance

◎: no corrosion on surface and lateral surface of Cu layer, underlying metal layer and alloy layer

○: slight corrosion on surface and lateral surface of Cu layer, underlying metal layer and alloy layer

△: partial corrosion on surface and lateral surface of Cu layer, underlying metal layer and alloy layer

Х: severe corrosion on surface and lateral surface of Cu layer, underlying metal layer and alloy layer

Table 2

	Stripping Performance (40℃)	Anticorrosive Performance 1	Anticorrosive Performance 2
Ex.1	○	◎	◎
Ex.2	◎	◎	◎
Ex.3	◎	◎	◎
Ex.4	○	◎	◎
Ex.5	◎	◎	◎
Ex.6	◎	◎	○
Ex.7	◎	◎	○
Ex.8	○	◎	◎
Ex.9	◎	◎	◎
Ex.10	◎	◎	◎
Ex.11	○	◎	◎
Ex.12	◎	◎	◎
Ex.13	◎	◎	○
C.Ex.1	◎	△	Х
C.Ex.2	◎	Х	Х
C.Ex.3	◎	Х	Х
C.Ex.4	○	△	Х

As is apparent from Table 2, the resist stripper compositions of Examples 1 ~ 13 using the organic compound having sulfone, sulfine or an ester as the stripper can exhibit equal or superior stripping performance and considerably higher anticorrosive effects on the metal layer including the Cu layer, compared to when using the resist stripper compositions of Comparative Examples 1 ~ 4 using amine or glycol ether.

Thus, the resist stripper composition according to the present invention can be confirmed to manifest excellent resist stripping effects even without the use of an amine compound.

Claims

A resist stripper composition for forming copper-based wiring, comprising, based on total weight of the composition, A) 1 ~ 45 wt% of one or more compounds selected from among compounds represented by Formulas 1 to 3 below, B) 0.01 ~ 5 wt% of an additive including an azole compound, and C) a remainder of a solvent including a compound represented by Formula 4 below:

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4, R₁, R₂, R₃ and R₄ are each independently a C1~6 alkyl group, and R₁ and R₂, or R₃ and R₄ are able to be linked with each other to form a C4~6 ring;

R₅ and R₆ are each independently hydrogen, a C1~4 alkyl group, a C1~4 hydroxyalkyl group, a C1~8 alkoxyalkyl group, -R₁₀-(OR₁₁)m-OR₁₂ or -R₁₃-(O)n-(C=O)-(O)o-R₁₄, in which m is a natural number from 1 to 4, n is 0 or 1, o is 0 or 1, R₁₀, R₁₁, R₁₃ and R₁₄ are each independently a C1~5 alkyl group, R₁₂ is hydrogen or a C1~5 alkyl group, and R₅ and R₆ are able to be linked with each other to form a C4~6 ring; and

R₇ is hydrogen or a C1~5 alkyl group, R₈ and R₉ are each independently hydrogen, a C1~4 alkyl group or a C1~4 hydroxyalkyl group, and R₇ and R₈ are able to be linked with each other to form a C4~6 ring,

wherein the alkyl group is a linear or branched alkyl group.
The resist stripper composition according to claim 1, wherein the compounds represented by Formulas 1 to 3 are selected from the group consisting of dimethylsulfoxide, diethylsulfoxide, dimethylsulfone, diethylsulfone, sulfolane, dipropyleneglycol methylether acetate, propyleneglycol methylether acetate, γ-butyrolactone, n-butylacetate, ethylbutanoate, and ethyllactate.
The resist stripper composition according to claim 1, wherein the azole compound comprises one or more selected from the group consisting of tolytriazole, 1,2,3-benzotriazole, 1,2,3-triazole, 1,2,4-triazole, 3-amino-1,2,4-triazole, 4-amino-4H-1,2,4-triazole, 1-hydroxybenzotriazole, 1-methylbenzotriazole, 2-methylbenzotriazole, benzotriazole-5-carboxylic acid, nitrobenzotriazole, 2-(2H-benzotriazol-2-yl)-4,6-di-t-butylphenol, and adenine.
The resist stripper composition according to claim 1, wherein the compound represented by Formula 4 comprises one or more selected from the group consisting of N-methylpyrrolidone, dimethylacetamide, dimethylformamide, N-methylformamide, acetamide, N-methylacetamide, N-(2-hydroxyethyl)acetamide, and 2-pyrrolidone.
The resist stripper composition according to claim 1, further comprising water.
The resist stripper composition according to claim 1, which does not contain an amine compound.
A method of manufacturing a semiconductor device using lithography for forming copper-based wiring, comprising removing a resist after use using the resist stripper composition of claim 1.
A method of manufacturing a flat panel display using lithography for forming copper-based wiring, comprising removing a resist after use using the resist stripper composition of claim 1.