TW201624153A - Etchant resist striping solution - Google Patents

Abstract

An object of the present invention is that a hard-baked etchant resist film is fixedly attached to a metal film on a bottom layer due to excessive polymerization of novolak resin and DNQ compound such that an etchant resist stripping solution that is commonly used for stripping etchant resist on a Cu film, a Cu/Mo film, and an Al film may not be capable of peeling off a hard-baked etchant resist film. A solution provided by the present invention is an etchant resist stripping solution that is characterized by comprising: tertiary amine, a polar solvent, water, cyclic amines, sugar alcohol, and a reduction agent, particularly an etchant resist stripping solution in which at least one of the compounds of pyrrolidine or pyrrolidine of which the third position bonded with a substitute group is used as the cyclic amine and hydrazine is used as the reduction agent.

Description

Resist stripper

The present invention is used for peeling off a stripping liquid for a resist for producing a liquid crystal display, an organic EL or the like, or a semiconductor, and more specifically, even a hard baked resist film can be used for resisting The agent does not substantially corrode the resist stripping solution of the aluminum film and the copper film.

A flat panel display (FPD) such as liquid crystal or organic EL (Electro-Luminescence) requires a large screen. On the other hand, for notebook computers, tablet computers, and smart phones, small high-resolution images are required. For a large screen, a TFT (Thin Film Transistor) using Cu wiring or Cu/Mo laminated wiring (hereinafter, simply referred to as "Cu wiring") is used. Moreover, for small high-resolution screens, TFTs using Al wiring are used. Further, in the following, Cu is referred to as copper, Mo is molybdenum, and Al is aluminum.

Among the panel manufacturers, there are cases in which TFTs using Al wiring and TFTs using Cu wiring are produced in one factory. When both the TFT using the Al wiring and the TFT using the Cu wiring are used, if the Al wiring can be used in the peeling step of the resist film, and the common resist stripping liquid is used in the case of using the Cu wiring, Can reduce production costs.

The water-based positive photoresist stripping solution is generally composed of an alkanolamine, a polar solvent, and water, and is heated to 40 to 50 ° C in a resist stripping apparatus. Use it left and right.

The alkanolamine system can dissolve the carboxyl group of the DNQ (azonaphthoquinone) compound of the alkali insoluble agent in the positive photoresist stripping solution in an essential component of the polar solvent and water by the nucleation action. The alkanolamine can be classified into primary, secondary and tertiary depending on the number of substituents other than hydrogen bonded to nitrogen. Among them, the smaller the known number, the stronger the alkalinity and the stronger the nuclear property.

Therefore, the smaller the number of the alkanolamines, the greater the ability of the DNQ compound of the alkali insoluble agent to be dissolved in the polar solvent and water, and the strong resist peeling performance can be exhibited.

On the other hand, alkanolamines are known to have chelation with Cu. For the chelation of Cu, the Cu film is corroded because it dissolves Cu. For the chelation of Cu, as with the basic or nuclear property, the number of alkanolamines is as small as possible. Therefore, the smaller the number of alkanolamines, the more corrosive to the Cu film.

The production process of the high-resolution TFT using the Al wiring is a dry etching step of a semiconductor (amorphous germanium: also referred to as "a-Si"), and the resist is damaged and denatured, and it becomes difficult to peel off. The case of a resist. This is considered to be because the DNQ compound constituting the positive resist film is excessively polymerized with the phenol resin.

The Al wiring is not corroded by the alkanolamine (chelation). Therefore, in order to peel off the denatured resist, a primary alkanolamine having strong peeling properties is generally used.

On the other hand, in the case of Cu wiring, when a primary or secondary alkanolamine is used, unacceptable Cu wiring corrosion often occurs. Therefore, there is a proposal to use a tertiary alkanolamine stripping solution. The tertiary chain alkanolamine has a weak chelation effect on Cu, and can suppress the corrosion of the Cu film in a practically problem-free range. but, It is also weaker than alkaline or core-requiring, and has a disadvantage in that the resist peeling ability is weak as compared with the resist stripping solution using the primary or secondary alkanolamine.

In such a technical background, it is required to have a peeling performance equal to or higher than that of the resist stripping liquid for Al wiring using the primary alkanolamine, and it is possible to combine the resist stripping liquids for both the Cu wiring and the Al wiring. Things.

Further, Patent Document 1 discloses a resist stripping solution of a compound represented by the formula (1) and a solvent. This resist stripping solution is used as a resist stripping step in the Cu wiring and the Al wiring.

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent No. 5297992

The resist film is used for forming wiring or the like through an etching step after exposure and development. Here, a step called post-baking is passed before the etching step. This is done for the purpose of making the resist film harder before etching. By post-baking, the polymerization of the DNQ compound of the phenolic resin constituting the resist film and the alkali insoluble agent is promoted, and the resist film is inhibited from gold by the etching step. The film surface is peeled off.

However, in the post-baking step, if the heating temperature rises excessively (hard baked state), the polymerization of the phenol resin and the DNQ compound is excessively promoted in the resist film, resulting in failure to use the previous resist stripping solution. Stripped.

In this regard, in Patent Document 1, the hard baking was investigated, and the resist was peeled off even under the hard baking condition of 160 ° C for 5 minutes. Therefore, even in the case of an unexpected situation that may occur in the production of hard baking, the peeling liquid of Patent Document 1 can peel off the resist.

However, the compound of the formula (1) has a problem of not being a reagent or an industrial raw material, but a commercially available special compound.

The present invention has been made in view of the above problems, and it is not necessary to stop the production line even if the problem of hard baking occurs in the manufacturing step, and it is possible to peel off the etching resist film and to remove the Cu wiring and the Al wiring. A common resist stripper.

More specifically, the resist stripping solution of the present invention comprises: a tertiary amine, a polar solvent, water, a cyclic amine, a sugar alcohol, and a reducing agent, wherein the cyclic amine contains 0.5 mass of the total amount. More than %, less than 2.0% by mass, the above reducing agent is a hydrazine.

The resist stripping liquid of the present invention can be used in a resist stripping step of Cu wiring (including Cu/Mo laminated wiring) and Al wiring. Further, even if the resist film is subjected to hard baking, the resist film can be peeled off. Also, about this issue In the bright resist stripping solution, the hard baked resist film can be peeled off, and on the other hand, the Cu film, the Mo film disposed on the Cu film underlayer, or the Al film is not damaged.

Therefore, even if the resist film on the aluminum film or the resist film on the copper film is peeled off, one type of resist stripping liquid can be peeled off. That is, it is not necessary to prepare a peeling step line of a plurality of resist films, and the resist stripping liquid can be managed only by one type. Again, there is no need for ashing steps. As a result, the plant's productivity and cost reduction can be greatly contributed.

1‧‧‧Substrate

2‧‧‧Mouth Department

3‧‧‧ bottom layer

4‧‧‧ (membrane) surface

5‧‧‧ taper angle

6‧‧‧ Taper surface

10‧‧‧ gap

Fig. 1 is a view showing the taper angle of the Cu/Mo laminated film and the Mo undercut.

The resist stripping liquid of the present invention will be described below. In addition, the following description shows an embodiment of the photoresist stripping liquid of the present invention, and the following embodiments and examples can be changed without departing from the scope of the present invention.

The resist film to which the resist stripping liquid of the present invention is peeled off is assumed to be a positive resist. The positive resist contains a phenolic resin as a resin, and is used as a sensitizer azoquinone (DNQ) compound. When etching is performed, a resist film is formed on the substrate, and exposure is performed via a pattern.

By this exposure, the DNQ compound is changed to a decenone. When the decenone meets with water, it becomes a hydrazine carboxylic acid and dissolves in water. The phenolic resin originally has a property of being dissolved in an alkaline solution, but the DNQ compound protects the dissolution point. DNQ compounds are degraded by exposure, by being soluble in aqueous developers, The phenolic resin also began to dissolve. Patterning of the resist film is thus completed.

The substrate in which the boundary resist film is patterned is subjected to wet etching or dry etching treatment via post-baking. The post-baking is performed to polymerize the phenol resin and the DNQ compound in the resist film to some extent. It is usually heat treated at 140 ° C for about 5 minutes. In the present specification, the term "hard baking" means heating at 150 ° C for 5 minutes or longer. When the baking temperature is raised by the phenol resin and the DNQ compound, the polymerization proceeds rapidly, and adheres firmly to the metal film of the underlayer, and becomes less soluble. The resist stripping liquid of the present invention is also targeted to a resist film which has been subjected to such hard baking.

The resist stripping liquid of the present invention contains a tertiary amine, a polar solvent, water, and an additive. Further, the additive contains a cyclic amine, a sugar alcohol, and a reducing agent.

The tertiary amine can make good use of triethylenediamine (TEDA), N-methyldimethanolamine (MDEA). These can also be used in combination. The total amount of the stripping liquid is preferably 0.1 to 9% by mass, more preferably 0.1 to 5% by mass, and most preferably 0.1 to 3% by mass. When the amount of the tertiary amine is too small, the dissolution of the Mo layer by the cyclic amine cannot be suppressed for the Cu/Mo laminated film. On the other hand, if it is too much, since the tertiary amine absorbs carbon dioxide in the air, peeling of the resist film of a cyclic amine will be inhibited, and peeling will not become possible. Therefore, in particular, when the peeling time is made longer, it is preferable to contain a tertiary amine.

The polar solvent may be any organic solvent having affinity with water. Further, it is more preferable to be excellent in miscibility with the above tertiary amine.

Such a water-soluble organic solvent may, for example, be an anthracene such as dimethyl hydrazine; an anthracene such as dimethyl hydrazine, diethyl hydrazine, bis(2-hydroxyethyl) fluorene or tetramethylene hydrazine; N,N-dimethylformamide, N-methylformamide, N,N-dimethylacetamide, N-methylacetamide, N,N-diethylacetamide, etc. Amidoxime; N- Indole amines such as methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-hydroxymethyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone An imidazolidinone such as 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone or 1,3-diisopropyl-2-imidazolidinone; Ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol, diethylene glycol monomethyl Diethylene glycol monoalkyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, such as ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether Polyols such as propylene glycol monoalkyl ethers such as ethers (lower alkyl groups having an alkyl group carbon atom of 1 to 6), and derivatives thereof. Among these, at least one selected from the group consisting of dimethyl hydrazine, N-methyl-2-pyrrolidone, and diethylene glycol monobutyl ether can be preferably used, and is selected from the group consisting of ethylene glycol, diethylene glycol, and propylene glycol. At least one kind of mixture. Among them, a positive type resist is obtained by using a mixed solution of diethylene glycol monobutyl ether (BDG) and propylene glycol (PG) as a polar solvent.

Further, as the resist stripping liquid of the present invention, a mixed liquid of diethylene glycol monobutyl ether (BDG) and propylene glycol (PG) can be preferably used as the polar solvent. These polar solvents dissolve the resist film and make it easy to dissolve. In particular, propylene glycol swells the resist film, and diethylene glycol monobutyl ether (BDG) dissolves the resist film. Therefore, a polar solvent containing at least two liquids is effective.

The polar solvent is preferably 50 to 80% by mass based on the total amount of the resist stripping solution.

Addition as an additive is a cyclic amine, a sugar alcohol, and a reducing agent. The cyclic amine is preferably a five-membered cyclic amine, particularly a pyrrolidine or a substituent bonded to the position of the third position of pyrrolidine. Good use, for example, 3-methylpyrrolidine, (S)-3-B Pyrrolidine, 3-aminopyrrolidine, 3-acetamidopyrrolidine, 3-(N-ethinyl-N-ethylamino)pyrrolidine, 3-(N-ethinyl-N- Methylamino)pyrrolidine, (R)-3-hydroxypyrrolidine, 3-(ethylamino)pyrrolidine. These cyclic amines are effective for peeling off the hard baked resist film. In addition, pyrrolidine is a compound which is generally available as an intermediate of medical pesticides and a fragrance such as chewing gum. Therefore, the cost of the stripping liquid itself can be reduced.

The amount of the cyclic amine added is preferably 0.5% by mass or more and less than 2.0% by mass based on the total amount of the resist stripping liquid. It is preferably 0.8% by mass or more and 1.5% by mass or less. When the amount of the cyclic amine is too large, the copper film and the molybdenum film are corroded. If the amount is too high, the hard-baked resist film cannot be peeled off.

Sugar alcohol can make good use of sorbitol, xylitol, sucrose, mannitol, maltitol, lactitol and the like. These sugar alcohols can suppress the dissolution of the Al film in the resist stripping solution, and together with the reducing agent (amine), suppress the undercut of the Mo film.

Further, the sugar alcohol is preferably 0.5 to 10% by mass based on the total amount of the resist stripping solution. It is preferably 0.8 to 2.0% by mass. Sugar alcohols act as corrosion inhibitors. Therefore, it is preferable to contain a certain amount. However, there is little contribution to the peeling of the resist film. On the other hand, when the addition of the sugar alcohol is excessive, when the resist stripper is distilled and regenerated, the scale remaining in the distillation apparatus may be caused. Therefore, it is preferable to contain in the above range.

A reducing agent that makes good use of hydrazine. The addition of a reducing agent inhibits Mo undercutting of the tertiary amine and the cyclic amine. The reducing agent is preferably in a range of 0.03 to 0.4% by mass based on the total amount of the resist stripping solution. It is more preferably in the range of 0.06 to 0.2% by mass. Further, hydrazine can also use water and substances from the viewpoint of operational safety.

[Examples]

Examples and comparative examples of the resist stripping liquid of the present invention are shown below. Two points of "resist peelability" and "corrosion of metal film" were evaluated for the resist stripper.

<Resist stripping property>

On the tantalum substrate, a tantalum oxide film of 100 nm was formed, and a copper film having a thickness of 300 nm was formed on the tantalum oxide film by sputtering. On the copper film, a positive resist liquid was applied by spin coating to prepare a resist film. After the resist film was dried, it was exposed to light using a wiring pattern. Then, with the developer, the resist of the photosensitive portion is removed. That is, the copper film has a state of a portion of the resist film of the wiring pattern and a portion where the copper film is exposed.

Next, the entire ruthenium substrate was post-baked at 150 ° C for 10 minutes. This is a step of reproducing the hard baking.

Next, the exposed copper film was removed by etching using a hydrogen peroxide-based copper etchant. After the etching of the copper film is completed, the resist film on the remaining copper pattern is peeled off using the sample resist stripper. The time for peeling off the resist film was studied in three stages after 40 seconds, 80 seconds, and 120 seconds. The substrate was then washed and subjected to interference observation by an optical microscope. When it was confirmed that there was a residual resist film on the copper film, "x" (fork) was observed, and when the residual resist film was not confirmed on the copper film, "○" (circle) was obtained. Furthermore, "○" (circle) means success or qualification, and "x" (fork) means failure or failure. The assessments below are also the same.

<Corrosion of metal film>

The corrosivity of the metal film was evaluated as follows. First, a 100 nm thermal oxide film was formed on a tantalum substrate, and a copper film having a thickness of 300 nm was formed on the tantalum oxide film by sputtering to prepare a Cu film sample. This is called "Cu gate". Similarly, a 20 nm thick molybdenum film was formed on the tantalum oxide film on the tantalum substrate, and a copper film having a thickness of 300 nm was formed thereon to prepare a laminated film sample of Cu/Mo. This is called "Cu/Mo gate". Further, an aluminum film having a thickness of 300 nm was formed on the tantalum oxide film on the tantalum substrate to prepare an Al film sample. This is called "Al gate".

A resist patterned into a wiring shape was formed on the evaluation samples as a substrate for corrosion evaluation. In other words, the substrate for evaluation of corrosion properties is composed of any one of a Cu film, a Cu/Mo film, and an Al film of a thermal oxide film formed on a tantalum substrate, and a resist having a wiring shape formed thereon.

These corrosive evaluation substrates are immersed in an etching agent for a copper film or an aluminum film at a time just after etching, and etched. Thereafter, the substrate for corrosion evaluation after the etching was immersed in the sample resist stripper for 6 minutes to peel off the resist film. After the substrate for corrosion evaluation was immersed in the sample resist stripping solution for 6 minutes, after washing and drying, the wiring portion was cut and the cut surface was observed.

Further, in the evaluation of corrosivity, the resist film was not subjected to heat treatment heated to a hard baked state. Further, the determination of the etching is performed from the start of etching until the time when the thermal oxide film can be visually confirmed.

The observation by the SEM (Scanning Electron Microscope) (SU Hitachi: SU8020 type) was carried out under the conditions of an acceleration voltage of 1 kV and 30,000 to 50,000 times.

The shape of the cut surface is shown in Fig. 1. Fig. 1(a) shows the shape of the cut surface in the case of Cu Gate and Al Gate. The shape of the cut surface of the portion just etched is a taper angle 5 which forms an angle of approximately 30 or 60 with respect to the substrate 1. The film portion 2 is a Cu film in the case of the Cu Gate and an Al film in the case of the Al Gate.

Fig. 1(b) shows the case of Cu/Mo Gate. In the case of Cu/Mo Gate, at least the upper Cu layer 2 has a taper angle of 5. The underlying Mo layer 3 is preferably etched along the tapered surface 6 of the Cu layer 2. However, as shown in Fig. 1(b), the residue can be etched compared to the Cu layer 2.

Corrosion evaluation was judged as a fork (×) when corrosion was confirmed on any of the surface 4 of the film portion 2 or the film portion 2 or the Mo layer 3 of the underlayer according to the observation of the cross-sectional shape, and no corrosion was observed. It is judged as a circle (○).

In particular, in the case of Cu/Mo Gate, as shown in Fig. 1(c), corrosion occurs between the Mo layer 3 and the Cu layer 2 of the underlayer. That is, Mo is dissolved by the interface between the copper layer 2 and the molybdenum layer 3, and the molybdenum layer 3 is selectively etched faster than the copper layer 2. Therefore, when a gap is confirmed between the underlying Mo layer 3 and the Cu layer 2, it is evaluated as a cross (x).

<Sample resist stripping solution>

The sample resist stripper was prepared in the following manner. The sample resist stripper is composed of a tertiary amine, a polar solvent, water, and an additive.

(1) Embodiment 1

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 25.6 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 0.8% by mass

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Example 1.

Further, the 0.1 mass of the hydrazine monohydrate corresponds to 0.064% by mass of the hydrazine. The remaining 0.036% by mass of the hydrazine-water and the substance is water. Therefore, the composition ratio of the above water, including the portion to which the hydrazine-water and the substance are charged, is 30.036% by mass. In all of the following examples and comparative examples, when hydrazine monohydrate was used, the same label was used.

(2) Embodiment 2

Example 2 is an increase in the amount of the additive compared to Example 1.

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Example 2.

(3) Embodiment 3

In Example 3, the type of the tertiary amine was changed.

N-methyldiethanolamine was used as the tertiary amine.

N-methyldiethanolamine (MDEA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Example 3.

(4) Embodiment 4

In Example 4, the third amine was changed back to TEDA in Example 3, and the type of the cyclic amine of the additive was changed.

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

3-(ethylamino)pyrrolidine (EAPRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Example 4.

Further, 3-(ethylamino)pyrrolidine is a compound represented by the following formula (2).

The results of the sample resist stripping liquid compositions of the above Examples 1 to 4, and the results of "resist stripping property" and "corrosion of the metal film" are shown in Table 1.

(5) Comparative Example 1

Comparative Example 1 is a composition having a large amount of the cyclic amine of the additive of Example 1. Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.4% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 2.0% by mass

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 1.

(6) Comparative Example 2

In Comparative Example 2, the composition of the sugar alcohol used as an additive was not used in Example 3 (PRL = 1.5% by mass).

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 26.4% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 2.

(7) Comparative Example 3

In Comparative Example 3, the type of the reducing agent added as an additive was changed in Example 2 (PRL = 1.5% by mass).

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Monomethyl hydrazine (MMHN) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 3.

(8) Comparative Example 4

In Comparative Example 4, the type of the reducing agent added as an additive was changed for Comparative Example 3.

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Ethylene hydrazine (AHD) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 4.

(9) Comparative Example 5

In Comparative Example 5, the type of the reducing agent added as an additive was changed in Comparative Example 3.

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Diamine carbonate (HC) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 5.

(10) Comparative Example 6

In Comparative Example 6, the type of the reducing agent added as an additive was changed for Comparative Example 3.

Triethylenediamine is used as the tertiary amine.

Triethylenediamine (TEDA) 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a five-membered cyclic amine, a sugar alcohol, and a reducing agent are added.

Pyrrolidine (PRL) 1.5% by mass

Sorbitol (Stol) 1.5% by mass

Carbonium (CHD) 0.1% by mass

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 6.

The results of the sample resist stripping liquid compositions of Comparative Examples 1 to 6 and the results of "resist stripping property" and "corrosion of metal film" are shown in Table 2.

Next, in order to confirm the peeling effect of the five-membered cyclic amine of the additive, The following comparison example is performed.

(11) Comparative Example 7

Contains no tertiary amines.

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

Additives, only five-membered cyclic amines are added.

2-methylpyrrolidine 2.0% by mass

Further, 2-methylpyrrolidine is bonded to a methyl group at the position of the second position of pyrrolidine.

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 7.

(12) Comparative Example 8

Contains no tertiary amines.

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, only five-membered cyclic amines were added.

1-methylpyrrolidine 2.0% by mass

Further, 1-methylpyrrolidine is bonded to the methyl group at the position (the position of nitrogen) of the first position of pyrrolidine.

The above mixing and stirring was used as the sample resist stripping liquid of Comparative Example 8.

Sample resist stripping solution group of Comparative Examples 7 and 8 above The results of "resist stripping property" and "corrosion of metal film" are shown in Table 3.

[Table 1]

[Table 2]

In the first table and the second table, each % indicates the mass % of the total amount of the resist stripping solution. Further, TEDA means triethylenediamine, MDEA-based N-methyldiethanolamine, PG-based propylene glycol, and BDG-based diethylene glycol monobutyl ether.

Refer to Table 1. When the cyclic amines (pyrrolidine) of Examples 1 and 2 and Comparative Example 1 (Second Table) were observed, the resist peeling time became shorter as the cyclic amine increased. On the other hand, referring to Comparative Example 1 (second table), a sample resist stripping solution of pyrrolidine was prepared at 2.0% by mass, and a laminated film of a Mo film and a Cu film was confirmed in "Cu/Mo gate". Undercut to Mo. That is, the total amount of the pyrrolidine to the resist stripping liquid is less than 2.0% by mass, preferably 1.5% by mass or less.

Further, even in the first example (pyrrolidine 0.8% by mass) which took the longest peeling time, the hard baked resist film was peeled off in a short time of 120 seconds.

Example 3 is based on N-methyldiethanolamine as the tertiary amine. Further, in Example 4, the cyclic amine of the additive was substituted with 3-(ethylamino)pyrrolidine. In this manner, the hard-baked resist film can be peeled off for 80 seconds without causing problems such as corrosion of the metal film or undercut of the Mo film.

Refer to Comparative Example 2 of Table 2. Comparative Example 2 contained 1.5% by mass of pyrrolidine and had no composition of sorbitol as a sugar alcohol. In Comparative Example 2, undercut of the Mo film occurred, and the Al film was etched. That is, in the resist stripping liquid of the present invention, a sugar alcohol is required when pyrrolidine is used.

In Comparative Example 3 to Comparative Example 6 of the second table, the hydrazine substituted for the reducing agent was changed to four types of monomethyl hydrazine, acetaminophen, hydrazine hydride, and carbon hydrazine. Monomethylamine and acetamide are combined to form Mo undercut.

On the other hand, although the metal carbonate was not corroded by the hydrazine carbonate and the carbonium, the hard baked resist film could not be peeled off.

Referring to the third table, the pyrobetane used in the example was used, and the hard baked resist release film was peeled off for 40 seconds (refer to Comparative Example 1). On the other hand, 1-methylpyrrolidine and 2-methylpyrrolidine, which are bonded to the methyl group at the position of the first position and the position of the second position, cannot be hard-baked even after 120 seconds. The etchant film is peeled off. From the above, it is possible to obtain a pyrrolidine in which the substituent is bonded to the position of the first position of the pyrrolidine and the position of the second position, and the hard-baked resist film cannot be peeled off in a practical range.

Further, on the other hand, 3-(ethylamino group) as shown in Example 4 Pyrrolidine, a pyrrolidine having a substituent at the position of the third position, and a usual pyrrolidine having no bonding substituent represented by Examples 1 to 3, the hard-baked resist film can be peeled off.

As described above, the resist stripping solution of the present invention can be used in a resist of a Cu film, a Cu/Mo film, or an Al film by including a tertiary amine, a polar solvent, water, a cyclic amine, a sugar alcohol, and a reducing agent. The stripping step is shared. Further, even a hard baked resist film can be peeled off.

[Industry profitability]

The resist stripping liquid of the present invention can be suitably used as a resist stripping liquid in the case of using a positive resist. This can be generally used well in the manufacture of FPDs such as liquid crystal displays, plasma displays, organic ELs, and the like.

Claims (4)

A resist stripping solution comprising: a tertiary amine, a polar solvent, water, a cyclic amine, a sugar alcohol, and a reducing agent, wherein the cyclic amine contains 0.5% by mass or more and less than 2.0% by mass based on the total amount. The above reducing agent is a hydrazine. The resist stripping solution according to claim 1, wherein the sugar alcohol is sorbitol. The resist stripping solution according to claim 1 or 2, wherein the tertiary amine is triethylenediamine or N-methyldiethanolamine. The resist stripping solution according to claim 1, wherein the tertiary amine is 0.1 to 9% by mass, the polar solvent is 50 to 80% by mass, and the water is 10 to 50% by mass, and the sugar alcohol is the same. The amount of the reducing agent is from 0.03 to 0.4% by mass, and the reducing agent is from 0.03 to 0.4% by mass.