TW201635051A - Resist stripping liquid - Google Patents

Abstract

A hard-baked resist film is firmly fixed to a base metal film when a novolac resin and a DNQ compound are excessively polymerized. Therefore, in some cases, the hard-baked resist film could not be stripped by means of a common resist stripping liquid capable of stripping a resist film disposed on a Cu film, a Cu/Mo film, or an Al film. Provided is a resist stripping liquid characterized by containing a cyclic amine, a polar solvent, water, a sugar alcohol, and a reductant, particularly wherein at least one from among pyrrolidine and a compound having a substituent bonded at a 3-posistion of pyrrolidine is used as the cyclic amine and hydrazine is used as the reductant.

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 liquid of the present invention is characterized by comprising pyrrolidine or a five-membered cyclic amine having a substituent at the third position of pyrrolidine, a polar solvent, water, a cyclic amine, a sugar alcohol, And the reducing agent, the cyclic amine is contained in an amount of 0.5% by mass or more and less than 3.0% by mass based on the total amount, and the reducing agent is less than 0.0128% by mass and more than 0.512% by mass. Further, it may contain a high boiling point solvent.

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. Again, even The resist film is subjected to hard baking, and the resist film may be peeled off. Further, in the resist stripping liquid of the present invention, the hard baked resist film can be peeled off as described above, and the Cu film or the Mo film disposed on the Cu film underlayer or the Al film is not caused. damage.

Therefore, even if the resist film on the aluminum film or the resist film on the Cu 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.

Further, since the resist stripping liquid of the present invention contains a sugar alcohol, when the distillation is carried out, the sugar alcohol having the highest boiling point among the components is finally solidified in the distillation column. However, by containing a high-boiling solvent having a boiling point to the extent that the residue remains as a residue with the sugar alcohol, it is possible to suppress the sugar alcohol from remaining solidified in the distillation column as a residue.

1‧‧‧Substrate

2‧‧‧Mouth Department

3‧‧‧Mo layer (bottom layer)

4‧‧‧ (film part 2) surface

5‧‧‧ taper angle

6‧‧‧ Taper surface

7‧‧‧ etching residue

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. Positive resist containing phenolic resin as a tree The lipid 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. The DNQ compound is degraded by exposure, and the phenolic resin also begins to dissolve by being soluble in the aqueous developer. Patterning of the resist film is thus completed.

The patterned substrate is completed by a resist film, and 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 cyclic amine, a polar solvent, water, and an additive. Further, the additive contains a sugar alcohol and a reducing agent. Further, it may contain a high boiling point solvent.

The polar solvent may be any organic solvent having affinity with water. 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-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-hydroxymethyl Indoleamines such as 2-pyrrolidone and N-hydroxyethyl-2-pyrrolidone; 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1 , imidazolidinone such as 3-diisopropyl-2-imidazolidinone; ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether Diethylene glycol monoalkyl ethers such as acetate, ethylene glycol monoethyl ether acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether a polyhydric alcohol such as propylene glycol monoalkyl ether (alkyl group carbon atom: 1 to 6 lower alkyl group) such as propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether or propylene glycol monobutyl ether, and derivative.

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.

Moreover, the resist stripping liquid of the present invention may contain a high boiling point solvent having the same boiling point as the residue remaining with the sugar alcohol described later. The high boiling point solvent preferably has a higher boiling point than the component used as the polar solvent. Further, the high boiling point solvent is preferably one which dissolves the sugar alcohol and the resist component. Furthermore, it is preferred to be easily soluble in water. Therefore, the high boiling point of the polyols can be well utilized. The sugar alcohol and the resist component are finally left as a residue when the resist stripping liquid is distilled and regenerated. this It is used to prevent the solidification of the residues.

For example, a propylene glycol (boiling point of 188 ° C) and diethylene glycol monobutyl ether (boiling point of 230 ° C) are used as a polar solvent which can be suitably used, and a solvent having a boiling point higher than 230 ° C is used. In this case, specific polyhydric alcohol high-boiling solvents include glycerin (boiling point 290 ° C), diethylene glycol (boiling point 244 ° C), 1,5-pentanediol (boiling point 242 ° C), 1,6-hexanediol. (boiling point: 250 ° C), 1,7-heptanediol (boiling point: 258 ° C), 1,10-nonanediol (boiling point: 297 ° C), and the like.

Further, examples of the ethers in the polyhydric alcohols include ethylene glycol monophenyl ether (boiling point: 245 ° C), triethylene glycol monomethyl ether (boiling point: 249 ° C), and diethylene glycol dibutyl ether (boiling point: 256 ° C), Ethylene glycol butyl methyl ether (boiling point 261 ° C), polyethylene glycol dimethyl ether (boiling point 264 ~ 294 ° C), tetraethylene glycol dimethyl ether (boiling point 275 ° C), polyethylene glycol monomethyl ether (boiling point 290 ~ 310 ° C) and so on.

The polar solvent is preferably 50 to 80% by mass based on the total amount of the resist stripping solution. Further, when a high boiling point solvent is used in combination, the high boiling point solvent is preferably contained in an amount of from 1% by mass to 5% by mass.

The cyclic amine is preferably a five-membered cyclic amine, particularly preferably pyrrolidine or a substituent at the position of the third position of pyrrolidine. Goodly used, for example, 3-methylpyrrolidine, (S)-3-ethylpyrrolidine, 3-aminopyrrolidine, 3-ethylamidopyrrolidine, 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 cyclic amine added, the total amount of resist stripping solution, to 0.5 mass More than % and less than 3.0% by mass are preferred ranges. It is preferably 0.8% by mass or more and 2.5% by mass or less. When the amount of the cyclic amine is too large, the copper film and the molybdenum film are corroded, and if too small, the hard-baked resist film cannot be peeled off.

Addition as an additive is a sugar alcohol and a reducing agent. 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 has a total amount of the resist stripping liquid of more than 0.0128% by mass, preferably less than 0.512% by mass. The range of 0.06 mass% or more and 0.4 mass% or less (0.06 mass% or more and 0.4 mass% or less) is more preferable. Further, hydrazine can also use water and substances from the viewpoint of operational safety. For example, when hydrazine 1 water and a substance are used, the ratio of the above-mentioned reducing agent is more than 0.02% by mass, and is less than 0.8 mass. Further, a more specific range is 0.094% by mass or more and 0.63% by mass or less.

[Examples]

Examples and comparative examples of the resist stripping liquid of the present invention are shown below. For the resist stripping solution, evaluate the "resist stripping property" and "gold" It is two points of the corrosiveness of the film.

<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 form a laminated film of Cu/Mo. Product. 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 4 minutes to peel off the resist film. After the substrate for corrosion evaluation was immersed in the sample resist stripping solution for 4 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. Further, the surface of the copper film after the resist was peeled off was also observed.

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. Cu/Mo Gate In this case, 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 7 can be etched compared to the Cu layer 2.

According to the observation of the cross-sectional shape, it was judged as "x" (fork) when the film portion 2 or the surface 4 of the film portion 2 or the Mo layer 3 of the bottom layer was confirmed to be corroded, and no observation was observed. When it is corroded, it is judged as "○" (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 "x" (fork).

Moreover, the state of the surface of the copper layer 2 was observed by SEM. The copper film is immersed in the resist stripper for a long time and is corroded. This can be grasped by the surface observation of the SEM. It was confirmed that the surface of the copper layer 2 was significantly corroded, and it was evaluated as "x" (fork).

<Sample resist stripping solution>

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

(1) Embodiment 1

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 0.8% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 27.6 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

Further, 0.1% by mass of the hydrazine monohydrate is equivalent to 6% by mass of the hydrazine. The remaining 0.036% by mass of the hydrazine-water mixture is water. Therefore, the composition ratio of the above water, including the portion to which the hydrazine-water and the substance are supplied, can be said to be 30.036 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 increased the amount of cyclic amine. The increased fraction of pyrrolidine is adjusted with the polar solvent PG.

The cyclic amine uses a pyrrolidine of a five-membered cyclic amine.

Pyrrolidine (PRL) 1.5% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 26.9 mass%

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(3) Embodiment 3

In Example 3, the kind of the cyclic amine of Example 2 was changed.

5-(ethylamino)pyrrolidine (EAPRL), a five-membered cyclic amine, was used as the cyclic amine.

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

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 26.9 mass%

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

Additives, add sugar alcohol and reducing agent.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

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

(4) Embodiment 4

In Example 4, glycerin was further added to the polar solvent of Example 1. The increased portion of glycerol is adjusted with the polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 0.8% by mass

Polar solvent, mixed 3 kinds

Propylene glycol (PG) 25.6 mass%

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Glycerin 2.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(5) Embodiment 5

In Example 5, glycerin was further added to the polar solvent of Example 2. The increased portion of glycerol is adjusted with the polar solvent PG.

The cyclic amine uses a pyrrolidine of a five-membered cyclic amine.

Pyrrolidine (PRL) 1.5% by mass

Polar solvent, mixed in 3 kinds.

Propylene glycol (PG) 24.9 mass%

Diethylene glycol butyl ether (BDG) 40.0% by mass

Glycerin 2.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(6) Embodiment 6

Example 6 further added glycerin to the polar solvent of Example 3. The increased portion of glycerol is adjusted with the polar solvent PG.

5-(ethylamino)pyrrolidine (EAPRL), a five-membered cyclic amine, was used as the cyclic amine.

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

Polar solvent, mixed in 3 kinds.

Propylene glycol (PG) 24.9% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Glycerin 2.0% by mass

Water 30.0% by mass

Additives, add sugar alcohol and reducing agent.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(7) Embodiment 7

Example 7 increased the pyrrolidine (0.8% by mass) of Example 1 to 2.0% by mass. The increased fraction of pyrrolidine is adjusted with the polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 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 sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(8) Example 8

Example 8 increased the pyrrolidine (0.8% by mass) of Example 1 to 2.5% by mass. The increased fraction of pyrrolidine is adjusted with the polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 2.5% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 25.9% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(9) Embodiment 9

Example 9 The amount (0.1% by mass) of the hydrazine monohydrate (pyrrolidine: 1.5% by mass) of Example 2 was increased to 0.6% by mass. Increase in hydrazine-water and substances The fractions were adjusted with a polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 1.5% 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 sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.6% by mass

(0.384% by mass in terms of hydrazine)

The above mixing and stirring was used as the sample resist stripping liquid of Example 9.

The results of the sample resist stripping liquid compositions of the above Examples 1 to 9 and the results of "resist stripping property" and "corrosion of the metal film" are shown in Table 1. In addition, in the first table, the composition ratio of the hydrazine monohydrate is represented by "a hydrazine-converted value".

(10) Comparative Example 1

Comparative Example 1 was a composition in which pyrrolidine (0.8% by mass) of Example 1 was increased to 3.0% by mass. The increased fraction of pyrrolidine is adjusted with the polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 3.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 25.4% by mass

Diethylene glycol monobutyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.1% by mass

(0.064% by mass in terms of hydrazine)

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

(11) Comparative Example 2

In Comparative Example 2, the amount of the reducing agent (HN = 0.1% by mass) of Example 2 (PRL = 1.5% by mass) was increased to a composition of 0.8% by mass. The increased portion of the reducing agent is adjusted with the polar solvent PG.

A pyrrolidine of a five-membered cyclic amine was used as the cyclic amine.

Pyrrolidine (PRL) 1.5% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 26.2% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorbitol (Stol) 1.5% by mass

Hydrazine monohydrate (HN) 0.8 mass

(0.512% by mass in terms of hydrazine)

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

(12) Comparative Example 3

In Comparative Example 3, the amount of the reducing agent (HN = 0.1% by mass) of Example 2 (PRL = 1.50% by mass) was reduced to a composition of 0.02% by mass. Reduced amount of reducing agent Polar solvent PG adjustment.

The cyclic amine uses a pyrrolidine of a five-membered cyclic amine.

Pyrrolidine (PRL) 1.5% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 26.98% by mass

Diethylene glycol butyl ether (BDG) 40.00% by mass

Water 30.0% by mass

As an additive, a sugar alcohol and a reducing agent are added.

Sorb 1.50% by mass

Hydrazine monohydrate (HN) 0.02% by mass

(0.0128% by mass in terms of hydrazine)

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

The results of the sample resist stripping liquid compositions of Comparative Examples 1 to 3 and the results of "resist stripping property" and "corrosion of metal film" are shown in Table 2.

Next, as a sample for confirming the effectiveness of the specific cyclic amine in the resist stripping liquid of the present invention, the following comparative examples were prepared.

(13) Comparative Example 4

In Comparative Example 4, 2-methylpyrrolidine of a five-membered cyclic amine was used. Furthermore, no additives were added.

2-methylpyrrolidine 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass or more

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

(14) Comparative Example 5

Comparative Example 5 used 1-methylpyrrolidine of a five-membered cyclic amine. Furthermore, no additives were added.

1-methylpyrrolidine 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

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

(15) Comparative Example 6

Comparative Example 6 used 2-methoxymethylpyrrolidine of a five-membered cyclic amine. Furthermore, no additives were added.

2-methoxymethylpyrrolidine 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

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

(16) Comparative Example 7

Comparative Example 7 used 3-(ethylamino)pyrrolidine of a five-membered cyclic amine.

Furthermore, no additives were added.

3-(ethylamino)pyrrolidine 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

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

(17) Comparative Example 8

Comparative Example 8 used a pyrrolidine of a five-membered cyclic amine. Furthermore, no additives were added.

Pyrrolidine 2.0% by mass

Polar solvent, mixed in 2 types.

Propylene glycol (PG) 28.0% by mass

Diethylene glycol butyl ether (BDG) 40.0% by mass

Water 30.0% by mass

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

The results of the sample resist stripping liquid compositions of Comparative Examples 4 to 8 and the results of "resist stripping property" and "corrosion of metal film" are shown in Table 3. Further, regarding Comparative Examples 4 to 8, the immersion time was 6 minutes (the first table and the second watch system were 4 minutes).

In the first to third tables, each % indicates the mass % of the total amount of the resist stripping solution. Further, PG is propylene glycol, and BDG is diethylene glycol butyl ether.

Refer to Comparative Example 1 of Examples 1 to 3 and Table 2 of Table 1 To 3. In the cyclic amines of Examples 1 and 2 and Comparative Example 1 (Second Table), the resist peeling time became shorter as the cyclic amine increased. On the other hand, referring to Comparative Example 1 (second table), when a sample resist stripping solution of pyrrolidine is blended at 3.0% by mass, a "Cu/Mo gate", that is, a laminated film of a Mo film and a Cu film, Confirm the undercut of Mo. That is, the total amount of the pyrrolidine to the resist stripping liquid is preferably less than 3.0% by mass, more preferably 2.5% by mass or less.

Further, even in Example 1 (pyrrolidine 0.8 mass) which was the longest at the time of peeling, the hard baked resist film was peeled off for a short time of 120 seconds after the immersion.

Example 3 is the replacement of a cyclic amine with 3-(ethylamino)pyrrolidine. In Example 3, the hard-baked resist film was peeled off in 80 seconds, and there was no problem of corrosion of the metal film and undercut of the Mo film.

With reference to Comparative Example 2 and Comparative Example 3 of Table 2 and Examples 1 to 9 of the first table, the amount of the hydrazine monohydrate and the amount of the hydrazine monohydrate was 0.8% by mass or more, and the undercut of Mo was good, but the copper layer was confirmed. The surface is rough. It is believed that too much reducing agent will damage the copper layer. Further, when the hydrazine monohydrate content was 0.02% by mass or less, the undercut of Mo was confirmed.

Therefore, it can be said that the hydrazine monohydrate and the substance are less than 0.02% by mass and less than 0.8% by mass (in terms of the hydrazine equivalent value, more than 0.0128% by mass and less than 0.512% by mass).

Refer to Table 3. The third table indicates the effect on a specific five-membered cyclic amine. Comparative Example 4 is a 2-methylpyrrolidine having a substituent bonded at the 2-position, Comparative Example 5 is a 1-methylpyrrolidine having a substituent bonded at the 1-position, and Comparative Example 6 is at the 2-position. 2-methoxymethylpyrrolidine at a position where a substituent is bonded, and Comparative Example 7 is a 3-(ethylamino)pyrrolidine having a substituent at the 3-position. In Comparative Example 8, a pyrrolidine having no bonding substituent was used.

Using 3-(ethylamino)pyrrolidine (Comparative Example 7) and pyrrolidine (Comparative Example 8) of the examples, the hard-baked resist film was peeled off at 40 seconds to 80 seconds. On the other hand, methyl 1-methylpyrrolidine (Comparative Example 5) and 2-methylpyrrolidine (Comparative Example 4) and 2-methoxymethyl group bonded to the 2-position position at the 1-position position. In pyrrolidine (Comparative Example 6), even if it took 120 seconds, the hard-baked resist film could not be peeled off.

From the above, pyrrolidine having a substituent bonded to the 1-position of pyrrolidine and the position of 2 can be used, and the hard-baked resist film cannot be peeled off in a practical range.

On the other hand, such as 3-(ethylamino)pyrrolidine (Comparative Example 7), pyrrolidine having a substituent at the 3-position or a usual pyrrolidine having no bonding substituent (Comparative Example 8), The hard baked resist film can be peeled off. In Examples 1 to 3, it can be said that such pyrrolidine and 3-(ethylamino)pyrrolidine were adjusted so as not to cause Mo undercut.

Referring again to Table 1, Examples 4 to 6 are those in which the polar solvent of Examples 1 to 3 contains 2.0% by mass of glycerin. In these embodiments, the hard-baked resist film can be peeled off in 80 seconds to 120 seconds, and further, damage to the Cu gate or the Al gate is not caused, and undercut of Mo does not occur.

That is, it can be practically used as a resist stripping liquid. Further, since the resist stripping liquids of Examples 4 to 6 contain glycerin having a high boiling point, it is possible to prevent the sugar alcohol or the peeled resist component from being solidified in the distillation column during distillation and regeneration after use.

As described above, the resist stripping liquid of the present invention is contained by A cyclic amine, a polar solvent, water, a sugar alcohol, and a reducing agent can be commonly used in a resist stripping step of a Cu film, a Cu/Mo film, and an Al film. Further, even if the resist film is hard baked, it can be peeled off.

[Industrial availability]

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

Claims (4)

A resist stripping liquid comprising pyrrolidine or a 5-membered cyclic amine having a substituent at the 3rd position of pyrrolidine, a polar solvent, water, a cyclic amine, a sugar alcohol, and a reducing agent, the above cyclic amine, The total amount is 0.5% by mass or more and less than 3.0% by mass, and the reducing agent is less than 0.0128% by mass and more than 0.512% by mass. Further, it may contain a high boiling point solvent. 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 reducing agent is a hydrazine. The resist stripping liquid according to claim 1, which further has glycerin.