CN112805629A

CN112805629A - Resist stripping liquid

Info

Publication number: CN112805629A
Application number: CN202080005335.6A
Authority: CN
Inventors: 渊上真一郎; 铃木靖纪; 鬼头佑典
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2019-11-20
Filing date: 2020-07-31
Publication date: 2021-05-14
Anticipated expiration: 2040-07-31
Also published as: CN112805629B

Abstract

Providing: when a hard-baked resist is peeled from a copper/molybdenum laminated film, the side etching of copper and molybdenum is suppressed. A resist stripping liquid, comprising: 0.5 to 5 mass% of a 2-stage cyclic amine with respect to the total amount of the stripping solution, 5 to 10 mass% of a basic amino acid with respect to the 2-stage cyclic amine, 10 to 30 mass% of a protective agent with respect to the basic amino acid, 10 to 50 mass% of a sugar alcohol with respect to the 2-stage cyclic amine, an organic polar solvent, and water.

Description

Resist stripping liquid

Technical Field

The present invention relates to a resist stripping liquid used for stripping a photoresist used in photolithography.

Background

Broadcast transmission formats capable of providing high image quality such as 4K and 8K have been proposed, and test broadcasting has also been started. The television is also gradually providing a large screen in response thereto. A liquid crystal television is a mainstream of a television at present, and a transistor corresponding to a pixel is formed on a transparent substrate (glass) for a large screen. The forming utilizes photolithography.

Due to the enlargement of the screen, it is necessary to reduce the resistance of the conductive portion formed on the transparent substrate. Therefore, the conductive portion gradually utilizes copper. Copper has high conductivity. However, the adhesion to the transparent substrate is low. Therefore, molybdenum is used as a base layer between the transparent substrate and copper.

Molybdenum is known to be a metal that is generally not easily corroded, but is severely corroded when a two-layer structure with copper is formed.

Patent document 1 discloses a stripping solution for stripping a resist layer by etching two layers of a two-layer structure in which a copper layer is disposed on a molybdenum layer, and then using a 2-or 3-grade alkanolamine and an amino acid having no thiol group or amide structure and containing 2 or more nitrogen atoms, thereby inhibiting corrosion of molybdenum and stripping the resist.

In addition, patent document 1 is also characterized in that, when a corrosion inhibitor for copper such as benzotriazole is used, precipitates are generated on the surface of copper, and therefore, the corrosion inhibitor is not used.

In the related art, a transparent substrate larger than that used in the patent document 1 is used. Therefore, in the case of forming elements by photolithography on a large screen, strict production management that a failure of 1 element does not allow is also performed. Therefore, it is required that peeling of the applied photoresist film, which is directly related to an etching error, does not occur. As a result, the temperature of the baking process (also referred to as a baking process) of the photoresist before exposure tends to increase.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2010/073887

Disclosure of Invention

Problems to be solved by the invention

Amino acids are known to be strongly corrosive to copper. That is, although the degree of the stripping liquid of patent document 1 is low, an amino acid which strongly corrodes copper is used together with an amine which corrodes copper in the absence of a copper protective agent. However, the stripping liquid of patent document 1 also suppresses corrosion of copper and corrosion of molybdenum on the substrate.

The reason for this is considered as follows. When the stripping solution is used, reduction of oxygen is performed on the surface of copper. Therefore, electrons are supplied from the surface of the copper to the stripping solution side. Here, when amines which do not easily corrode copper are used, electrons are supplied not from copper but from molybdenum. Thus, molybdenum is corroded.

On the other hand, here, by utilizing the amino acid which corrodes copper at the same time, electrons are also released from copper, thereby suppressing corrosion of molybdenum. Namely, the following method: in the case of stripping a resist with an alkanolamine which does not readily corrode copper, the supply of electrons utilized in the reduction action occurring on the copper surface is supplied not only by molybdenum but also by copper itself.

That is, the molybdenum layer is protected by intentionally corroding the copper layer to some extent, and the two layers are intended to be protected by the balance of alkanolamine and amino acid.

However, at present, the baking temperature of the resist is higher in situ (hard baking) than that in the case of patent document 1, and the resist itself cannot be peeled off by the alkanolamine. Therefore, there is a need for a basic substance more suitable for decomposition of a hard-baked resist than an alkanolamine.

In addition, the conductive portions near the pixels are relatively fine patterns, and the conductive portions from the pixels are collected at the peripheral portion of the screen, and thus are wide patterns.

Therefore, when a strong base is used in a state where a wide pattern and a narrow pattern are mixed, there is a problem that it is difficult to adjust the balance between the amine and the amino acid. That is, in this method, molybdenum is corroded when the amino acid is substantially small (amine is large), and copper is corroded when the amino acid is large (amine is small). However, in both of the wide pattern and the narrow pattern, the range in which the amino acid and the amine are in equilibrium becomes very narrow, and a stripping solution that is balanced cannot be provided substantially.

Means for solving the problems

The present invention has been made in view of the above problems, and provides: the resist stripping liquid can sufficiently strip the hard baked photoresist, and can inhibit the corrosion of molybdenum and copper in the wide pattern part and the narrow pattern part.

Therefore, in the present invention, a copper protective agent is used in addition to the cyclic amine and the amino acid. In addition, the corrosion of molybdenum is inhibited by adding an excess amount of amino acid relative to amine, and the degree of corrosion of copper is regulated by a protective agent.

More specifically, the resist stripping liquid of the present invention is characterized by comprising:

0.5 to 5 mass% of a 2-stage cyclic amine based on the total amount of the stripping liquid,

5 to 10 mass% of a basic amino acid based on the 2-stage cyclic amine,

10 to 30 mass% of a protecting agent with respect to the basic amino acid,

10 to 50 mass% of a sugar alcohol based on the 2-stage cyclic amine,

An organic polar solvent, and water.

ADVANTAGEOUS EFFECTS OF INVENTION

The resist stripping liquid of the present invention is less likely to corrode copper, and a basic amino acid that strongly corrodes copper is excessively mixed into a highly basic 2-stage cyclic amine. Thus, copper is corroded in this case, but the corrosion of copper is regulated by the amount of the protective agent. That is, the effect of the etchant is suppressed by the protective agent as compared with the case where 2 etchants are balanced. Therefore, in both cases of a wide pattern and a narrow pattern, molybdenum corrosion and copper corrosion can be suppressed within a practical range.

In addition, since sugar alcohol is mixed, corrosion between molybdenum and copper can be suppressed.

Further, since the composition of the stripping solution does not contain an inorganic acid or an inorganic base, corrosion does not occur to the conductive portion of aluminum.

Detailed Description

Hereinafter, the resist stripping liquid of the present invention will be described with reference to examples. The following description is intended to illustrate one embodiment and one example of the present invention, and the present invention is not limited to the following description. The following description may be modified within the scope not departing from the gist of the present invention. In the following description, although the range "to" is sometimes used in the description, the range "from" not less than (including the value and greater than) to "less than (including the value and less than)" is meant.

The resist stripping solution of the present invention contains: a 2-stage cyclic amine, a basic amino acid, an organic polar solvent, a protective agent, water and a sugar alcohol.

In addition, the present invention is directed to a conductive portion in which copper is laminated on molybdenum. Particularly, the conductive part with the thickness of about 5-15 μm and the conductive part with the thickness of 300-500 μm are mixed. Furthermore, there are also conductive parts made of aluminum.

The thickness of the molybdenum is about 30-50 nm, and the thickness of the copper is 400-800 nm. The aluminum portion has a thickness of 200 to 400 nm. In contrast, the side etching of molybdenum, the etching of copper, and the etching of aluminum need to be within a range that is practically unproblematic.

In addition, the resist is a positive type photoresist, and includes a novolak resin and diazonaphthoquinone. The material is subjected to a baking treatment at 150 ℃ or higher. The photoresist is typically heat treated at a temperature of around 100 c. Therefore, the heat treatment at 150 ℃ or higher can be referred to as high-temperature treatment (hard baking).

The 2-stage cyclic amine can be suitably used with (3S) -3-hydroxypyrrolidine (CAS model No. 100243-39-8: hereinafter referred to simply as "3-hydroxypyrrolidine"), pyrrolidine (CAS model No. 123-75-1). The 3-hydroxypyrrolidine and pyrrolidine are capable of stripping the hard baked photoresist. The content of the 2-stage cyclic amine is preferably 0.5 to 5% by mass, more preferably 0.7 to 2.0% by mass, based on the total amount of the stripping liquid.

The amino acid may be a basic amino acid. Copper can be dissolved strongly. Arginine and lysine can be suitably used in particular. Histidine is classified as a basic amino acid, but the resist stripping solution of the present invention has little effect on the corrosion resistance of molybdenum.

The amino acid is preferably contained in an amount of 5 to 10% by mass, more preferably 6 to 8% by mass, based on the cyclic amine. The amount of the surfactant is 0.025 to 0.5% by mass in terms of the total amount of the stripping liquid.

The protective agent is a substance that inhibits corrosion of copper by amino acids. Specifically, benzotriazole, 5-methyl-1H-benzotriazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 1- [ N, N-bis (2-ethylhexyl) aminomethyl ] -1H-benzotriazole, 2' - [ [ (methyl-1H-benzotriazol-1-yl) methyl ] imino ] diethanol. Therefore, at least 1 substance selected from these compound groups is used as the metal surface protective agent.

The protective agent may be adjusted to 10 to 30% by mass relative to the basic amino acid. Which is 0.0025 to 0.15 mass% of the entire stripping solution. When the amount of the protective agent is too large relative to the amount of the basic amino acid, corrosion of copper is excessively suppressed, and corrosion of molybdenum increases. However, by containing the amount in the above range, the corrosion of molybdenum and the corrosion of copper can be suitably balanced even if the width of the conductive portion is wide or narrow.

The sugar alcohol can prevent corrosion of the boundary of molybdenum and copper (referred to as "undercutting of copper"). As the sugar alcohol, glycerin or sorbitol can be suitably used. The sugar alcohol is preferably contained in an amount of 10 to 50% by mass based on the cyclic amine. The amount of the stripping agent is 0.05-2.5% by mass relative to the total amount of the stripping agent.

The organic polar solvent is preferably an aprotic organic solvent. The protic organic solvent easily causes corrosion of molybdenum which becomes a base. Specifically, as the organic polar solvent, diethylformamide, N-methylformamide, dimethylformamide, N-methyl-2-pyrrolidone, tetrahydrofuran, dimethylsulfoxide, or the like can be suitably used.

Preferably, water is 10 to 30 mass% of the entire stripping solution. In addition, the organic polar solvent may be the balance of the above cyclic amine, water, a protecting agent and a sugar alcohol.

[ examples ]

Examples of the resist stripping liquid of the present invention are shown below. Sample stripping solutions of examples and comparative examples having the compositions shown below were prepared, and a resist stripping test was performed on a resist stripping test piece.

< test piece for resist stripping >

Molybdenum (Mo) was deposited on a glass substrate at a thickness of 30nm, and copper (Cu) was laminated thereon at a thickness of 500 nm. On which SiN was laminated with a thickness of 300 nm. This is referred to as a silicon layer stack.

Contact holes having a diameter of 1 μm were formed at prescribed positions of the SiN layer on the silicon layer laminate. Further, molybdenum (Mo) was laminated in a thickness of 30nm, and copper (Cu) was laminated thereon in a thickness of 500 nm.

Next, a positive resist is applied to the uppermost copper layer, and firing (baking) is performed at a predetermined temperature. The high-temperature baking was performed at 150 ℃ for about 2 minutes, but in order to confirm the peeling force of the resist stripper, the baking was performed at 170 ℃ for 5 minutes. Thereby, the resist film is strongly subjected to the baking treatment. After baking, the copper test piece for resist stripping was obtained by exposing and developing the copper layer and the molybdenum layer on the upper layer in a gate pattern, and then etching the copper layer and the molybdenum layer.

That is, a molybdenum layer and a copper layer in which a gate line pattern was etched were present on a copper test piece for resist stripping, and a resist film subjected to baking treatment was deposited thereon. In addition, the resist film also covers the contact hole portion.

Further, aluminum (Al) was laminated on the silicon laminate in a thickness of 500nm, and the aluminum layer was etched in a gate pattern in the same manner as in the case of the copper test piece for resist stripping. The resist layer was baked at 170 ℃ for 5 minutes in the same manner. Thus, an aluminum test piece for resist stripping was obtained.

< evaluation >

As the ability to peel off the resist (hereinafter referred to as "peeling force"), each test piece was treated in each sample peeling solution heated to 40 ℃ for 40 seconds, and the residual state of the resist was confirmed by an optical microscope. In addition, in the case where the resist clearly remained on the surface, the evaluation was "x" (meaning of failure or failure), and if the resist was peeled off in a state without any problem, the evaluation was "good" (meaning of pass or success).

As an ability to suppress corrosion of the metal surface (hereinafter referred to as "metal damage"), the test piece was immersed in a sample stripping solution at 40 ℃ for 4 minutes, and the corrosion state of the metal film of the treated test piece was observed by SEM (Scanning Electron Microscope). In this observation, the etched portion was observed in the surface magnified view and the cross-sectional view.

In the enlarged surface view, the corrosion state of the surfaces of the copper layer and the aluminum layer was confirmed. In particular, the state of copper on the surface of the gate line and the edge portion of the contact hole was confirmed. In addition, in the cross-sectional view, the roughness state of the inclined surface of the etched metal layer, the inclination angle, and the undercut of copper were confirmed.

In each field, the evaluation of the state judged as not suitable for production was "x" (meaning of failure or failure), and the evaluation of the state judged as suitable for production was "good" (meaning of pass or success).

< sample stripping solution >

The composition of the stripping solution for each sample is shown. In order to show the following compounds, the following abbreviations may be used. 3-hydroxypyrrolidine: 3HD-PRL (CAS model: 100243-39-8), pyrrolidine: PRL (CAS model: 123-75-1), diethylformamide: DEF (CAS model: 617-84-5), N-methylformamide: NMF (CAS model: 123-39-7), diethylene glycol monobutyl ether: BDG (CAS model: 112-34-5), 2' - [ [ (methyl-1H-benzotriazol-1-yl) methyl ] imino ] bis ethanol: MBET (CAS model: 88477-37-6), N-methyl-2-pyrrolidone: NMP (CAS model: 872-50-4), piperazine: PIZ (CAS model: 110-85-0), N-methylethanolamine: MMA (CAS model: 109-83-1). 5-methylbenzotriazole: 5M-BTA (CAS model: 136-85-6), arginine: arg (CAS model: 74-79-3), lysine: lys (CAS model: 70-54-2), histidine: his (CAS model: 71-00-1), Glycerol: glycerol (CAS model: 56-81-5), sorbitol: stol (CAS model: 50-70-4).

(example 1)

The sample stripping solution of example 1 was prepared with the following composition.

1.0g of 3HD-PRL as a cyclic amine compound,

0.07g (7% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

Glycerin as a sugar alcohol 0.30g (30 mass% with respect to the cyclic amine compound), NMP as a polar solvent 71.62g, and water 27.0g were mixed to prepare a sample of example 1.

(example 2)

The sample stripping solution of example 2 was prepared with the following composition.

4.0g of 3HD-PRL as a cyclic amine compound,

0.32g (8% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.09g (28.1 mass% based on the amino acid) of MBET as a protecting agent,

Glycerin (1.60 g) (40 mass% based on the cyclic amine compound) as a sugar alcohol, DEF 66.99g as a polar solvent, and water (27.0 g) were mixed to prepare a sample of example 2.

(example 3)

The sample stripping solution of example 3 was prepared with the following composition.

PRL 1.0g as a cyclic amine Compound,

0.07g (7% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

0.30g (30% by mass based on the cyclic amine compound) of glycerin as a sugar alcohol,

71.62g of DEF and 27.0g of water as polar solvents were mixed to prepare a sample of example 3.

(example 4)

The sample stripping solution of example 4 was prepared with the following composition.

PRL 4.0g as a cyclic amine Compound,

0.32g (8% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.09g (28.1 mass% based on the amino acid) of 5M-BTA as a protecting agent,

1.60g (40% by mass based on the cyclic amine compound) of glycerin as a sugar alcohol,

66.99g of NMF as a polar solvent and 27.0g of water were mixed to prepare a sample of example 4.

(example 5)

The sample stripping solution of example 5 was prepared with the following composition.

PRL 3.0g as a cyclic amine Compound,

0.21g (7% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.03g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

Sorbitol as a sugar alcohol 0.90g (30% by mass based on the cyclic amine compound),

68.86g of DEF and 27.0g of water as polar solvents were mixed to prepare a sample of example 5.

(example 6)

The sample stripping solution of example 6 was prepared with the following composition.

PRL 1.0g as a cyclic amine Compound,

0.07g (7% by mass based on the cyclic amine compound) of Lys as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

0.10g (10% by mass based on the cyclic amine compound) of glycerin as a sugar alcohol,

NMP 71.82g and water 27.0g as polar solvents were mixed to prepare a sample of example 6.

Comparative example 1

The sample stripping solution of comparative example 1 was prepared with the following composition.

1.0g of 3HD-PRL as a cyclic amine compound,

0.03g (3% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.006g (20% by mass based on the amino acid) of MBET as a protecting agent,

NMP 71.664g and water 27.0g as polar solvents were mixed to prepare a sample of comparative example 1.

Comparative example 2

The sample stripping solution of comparative example 2 was prepared with the following composition.

4.0g of 3HD-PRL as a cyclic amine compound,

0.60g (15% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.18g (30% by mass based on the amino acid) of MBET as a protecting agent,

DEF 66.62g and water 27.0g as polar solvents. The above were mixed to prepare a sample of comparative example 2.

Comparative example 3

The sample stripping solution of comparative example 3 was prepared with the following composition.

PRL 1.0g as a cyclic amine Compound,

0.07g (7% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.003g (4.3% by mass based on the amino acid) of MBET as a protecting agent,

DEF 71.627g and water 27.0g as polar solvents were mixed to prepare a sample of comparative example 3.

Comparative example 4

The sample stripping solution of comparative example 4 was prepared with the following composition.

PRL 4.0g as a cyclic amine Compound,

0.32g (8% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.1g (31 mass% based on the amino acid) of 5M-BTA as a protecting agent,

66.98g of NMF as a polar solvent and 27.0g of water were mixed to prepare a sample of comparative example 4.

Comparative example 5

The sample stripping solution of comparative example 5 was prepared with the following composition.

PIZ as an amine Compound 1.0g,

0.07g (7% by mass based on the amine compound) of Arg as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

71.62g of DEF and 27.0g of water as polar solvents were mixed to prepare a sample of comparative example 5.

Comparative example 6

The sample stripping solution of comparative example 6 was prepared with the following composition.

MMA 1.0g as the amine compound,

0.07g (7% by mass based on the amine compound) of Lys as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

NMP 71.82g and water 27.0g as polar solvents were mixed to prepare a sample of comparative example 6.

Comparative example 7

The sample stripping solution of comparative example 7 was prepared with the following composition.

3.0g of 3HD-PRL as a cyclic amine compound,

0.21g (7% by mass based on the cyclic amine compound) of Lys as an amino acid,

0.03g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

0.0g of glycerin (not including sugar alcohol) as a sugar alcohol,

NMP 69.76g and water 27.0g as polar solvents were mixed to prepare a sample of comparative example 7.

Comparative example 8

The sample stripping solution of comparative example 8 was prepared with the following composition.

PRL 1.0g as a cyclic amine Compound,

0.07g (7% by mass based on the cyclic amine compound) of Arg as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

BDG 71.62g and water 27.0g as polar solvents were mixed to prepare a sample of comparative example 8.

Comparative example 9

The sample stripping solution of comparative example 9 was prepared with the following composition.

PRL 1.0g as a cyclic amine Compound,

0.07g (7% by mass based on the cyclic amine compound) of His as an amino acid,

0.01g (14.3 mass% based on the amino acid) of MBET as a protecting agent,

71.62g of DEF and 27.0g of water as polar solvents were mixed to prepare a sample of comparative example 9.

The sample peeling solution was prepared and subjected to a peeling test. The compositions of the sample stripping solutions of the examples and the results of the stripping tests are shown in table 1, and the compositions of the sample stripping solutions of the comparative examples and the results of the stripping tests are shown in tables 2 and 3.

[ Table 1]

[ Table 2]

[ Table 3]

Referring to table 1, examples 1 to 6, which are compositions of the present invention, can peel off the resist film subjected to the heat treatment under the conditions of 170 ℃ for 5 minutes under the treatment conditions of 40 ℃ for 40 seconds. Therefore, the evaluation of the peeling force was good. In addition, in observation by SEM, the state of the copper film in the gate line and the contact hole was also good, and the evaluation of metal damage was also good. In addition, the evaluation was also "good" for the side etching due to the corrosion of molybdenum and the side etching of copper between molybdenum and copper. Further, the evaluation of the peeling strength in the aluminum layer was good. In addition, the aluminum does not cause any problem in the examples and comparative examples.

On the other hand, comparative examples 1 and 2 are the case where the amino acid is too small (comparative example 1) and the case where the amino acid is too large (comparative example 2). When the amino acid content is too small, the molybdenum undergoes lateral erosion. The reason for this is that the copper film is not suitably corroded. On the other hand, when the amino acid is too much, the surface of copper is corroded.

In comparative examples 3 and 4, the amount of the protective agent was too small (comparative example 3) and too large (comparative example 4). If the amount of the protective agent is too small, corrosion of the copper film by the amino acid cannot be prevented. On the other hand, if the amount of the protective agent is too large, the copper surface cannot be corroded, and corrosion (side corrosion) of molybdenum occurs.

In comparative example 5, piperazine was used as the amine. Although piperazine is a cyclic amine, the hard baked resist film cannot be peeled. In comparative example 6, the amine was replaced with N-methylethanolamine (alkanolamine), and in this case, the hard-baked resist film could not be peeled off.

Comparative example 7 is a case where no sugar alcohol was added. In this case, corrosion occurs between molybdenum and copper, and lateral corrosion of copper (denoted as "cuu.c.") occurs.

In comparative example 8, diethylene glycol monobutyl ether was used as the polar solvent as the protic organic solvent. When the organic polar solvent is made protic, the molybdenum tends to undergo lateral erosion.

Comparative example 9 is a case where histidine is used as the amino acid. Although histidine is classified as a basic amino acid, lateral erosion of molybdenum occurs. In the composition of the stripping solution of the present invention, histidine is considered to be less corrosive to copper than lysine and arginine.

As described above, the resist stripping solution of the present invention can suppress surface roughening and undercutting caused by corrosion of molybdenum and copper when forming wirings made of molybdenum, copper, and aluminum by photolithography.

Industrial applicability

The present invention can be suitably used for a resist stripping step in a process for manufacturing a large-area display device.

Claims

1. A resist stripping liquid, comprising:

5 to 10 mass% of a basic amino acid based on the 2-stage cyclic amine,

10 to 30 mass% of a protective agent with respect to the basic amino acid,

10 to 50 mass% of a sugar alcohol based on the 2-stage cyclic amine,

An organic polar solvent, and

and (3) water.

2. The resist stripping solution according to claim 1, wherein the 2-stage cyclic amine is at least one of 3-hydroxypyrrolidine or pyrrolidine.

3. The resist stripping liquid according to any one of claims 1 or 2, characterized in that the basic amino acid comprises at least any one of arginine or lysine.

4. The resist stripping liquid according to any one of claims 1 to 3, wherein the protective agent is at least one selected from benzotriazole, 5-methyl-1H-benzotriazole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 1- [ N, N-bis (2-ethylhexyl) aminomethyl ] -1H-benzotriazole, 2' - [ [ (methyl-1H-benzotriazol-1-yl) methyl ] imino ] diethanol.

5. The resist stripping liquid according to any one of claims 1 to 4, wherein the sugar alcohol is at least one of glycerin and sorbitol.