WO2020203246A1

WO2020203246A1 - Method for producing active light sensitive or radiation sensitive resin composition, pattern forming method, and method for producing electronic device

Info

Publication number: WO2020203246A1
Application number: PCT/JP2020/011635
Authority: WO
Inventors: 聡上村
Original assignee: 富士フイルム株式会社
Priority date: 2019-03-29
Filing date: 2020-03-17
Publication date: 2020-10-08
Also published as: JP7301123B2; JPWO2020203246A1

Abstract

The first problem addressed by the present invention is to provide a method for producing an active light sensitive or radiation sensitive resin composition which is capable of forming a pattern that is suppressed in bridge defects. The second problem addressed by the present invention is to provide: a pattern forming method which uses an active light sensitive or radiation sensitive resin composition that is capable of forming a pattern that is suppressed in bridge defects; and a method for producing an electronic device.　A method for producing an active light sensitive or radiation sensitive resin composition according to the present invention produces an active light sensitive or radiation sensitive resin composition that is used in a semiconductor device production process, and comprises: a step A for purifying a polymer solution that contains a solvent and a resin which is decomposed by the action of an acid, thereby being increased in the polarity; and a step B for preparing an active light sensitive or radiation sensitive resin composition by adding a compound which generates an acid upon irradiation of active light or radiation to the polymer solution after the step A. The step A comprises a step X wherein the polymer solution is filtered by being passed through a filter X.

Description

Method for manufacturing a sensitive light-sensitive or radiation-sensitive resin composition, a method for forming a pattern, a method for manufacturing an electronic device

The present invention relates to a method for producing a sensitive light-sensitive or radiation-sensitive resin composition, a method for forming a pattern, and a method for producing an electronic device.

Since the resist for KrF excimer laser (248 nm), a pattern forming method using chemical amplification has been used to compensate for the decrease in sensitivity due to light absorption. For example, in the positive chemical amplification method, first, the photoacid generator contained in the exposed portion is decomposed by light irradiation to generate an acid. Then, in the post-exposure baking (PEB: Post Exposure Bake) process or the like, the alkali-insoluble group of the resin contained in the sensitive light-sensitive or radiation-sensitive resin composition is alkali-soluble by the catalytic action of the generated acid. The solubility in a developing solution is changed by changing the base. Then, for example, development is carried out using a basic aqueous solution. As a result, the exposed portion is removed to obtain a desired pattern.
Due to the miniaturization of semiconductor devices, the wavelength of the exposure light source has been shortened and the numerical aperture (NA) of the projection lens has been increased. Currently, an exposure machine using an ArF excimer laser having a wavelength of 193 nm as a light source has been developed. ing. Under these circumstances, various configurations have been proposed as sensitive light-sensitive or radiation-sensitive resin compositions (resist compositions).

Further, in recent years, with the demand for further miniaturization of the resist pattern, improvement of the surface defects of the resist pattern after development is further desired.
For example, in Patent Document 1, a resist composition containing a resin component, an acid-generating component that generates an acid upon exposure, and an organic solvent is filtered under specific conditions to develop a resist pattern surface after development. It discloses a method for suppressing defects.

Japanese Patent No. 04637967

When the resist composition was prepared and examined with reference to Patent Document 1, the present inventor found that surface defects (particularly, bridge defects) still occur on the pattern formed by the resist composition. ..

Therefore, it is an object of the present invention to provide a method for producing a sensitive light-sensitive or radiation-sensitive resin composition capable of forming a pattern in which bridge defects are suppressed.
Another object of the present invention is to provide a pattern forming method using a sensitive light-sensitive or radiation-sensitive resin composition capable of forming a pattern in which bridge defects are suppressed, and a method for manufacturing an electronic device.

As a result of diligent studies to solve the above problems, the present inventor has found that the above problems can be solved by the following configuration.

[1] A method for producing a sensitive light-sensitive or radiation-sensitive resin composition used in a semiconductor device manufacturing process.
Step A of purifying a polymer solution containing a resin and a solvent which are decomposed by the action of an acid and whose polarity is increased.
A step B of preparing a sensitive light-sensitive or radiation-sensitive resin composition by adding a compound that generates an acid by irradiation with active light or radiation to the polymer solution that has undergone the above step A is included.
A method for producing a sensitive light-sensitive or radiation-sensitive resin composition, wherein the step A comprises a step X in which the polymer solution is passed through a filter X and filtered.
[2] The filter X is selected from the group consisting of a nylon film having a pore diameter of 0.03 μm or less, a polyolefin resin film having a pore diameter of 0.01 μm or less, and a fluororesin film having a pore diameter of 0.01 μm or less [1]. The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to.
[3] The method for producing a sensitive actinic or radiation-sensitive resin composition according to [1] or [2], wherein the differential pressure of the filter X is 0.3 MPa or less.
[4] The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of [1] to [3], wherein the above step X is carried out in a temperature environment of 15 to 25 ° C.
[5] The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of [1] to [4], wherein the step A includes the step X twice or more.
[6] The above step A is
A step X0 in which the polymer solution is passed through the filter X0 and filtered, and a step X1 in which the polymer solution passed through the step X0 is passed through the filter X1 and filtered is included.
A step X1 in which the polymer solution is passed through the filter X1 and filtered, and a step X2 in which the polymer solution passed through the step X1 is passed through the filter X2 and filtered is included.
A step X0 in which the polymer solution is passed through the filter X0 and filtered, a step X1 in which the polymer solution passed through the step X0 is passed through the filter X1 and filtered, and the polymer solution passed through the step X1 is passed through the filter X2. Including step X2 of letting and filtering
The filter X0 and the filter X2 are filters different from the filter X1 and are selected from a polyolefin resin film having a pore diameter of 0.01 μm or less and a fluororesin film having a pore diameter of 0.01 μm or less, [1] to [ 4] The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of.
[7] The above step A is
With respect to the polymer solution comprising the step X0 of passing the polymer solution through the filter X0 and filtering, and the step X1 of passing the polymer solution through the step X0 and filtering the filter X1 and passing through the step X1. Then, once again, the step of carrying out the step X0 and the step X1 is included one or more times.
For the polymer solution comprising the step X1 of passing the polymer solution through the filter X1 and filtering, and the step X2 of passing the polymer solution through the filter X2 and filtering the filter X2, and passing through the step X2. Then, the step of carrying out the step X1 and the step X2 is included once or more, or
The step X0 in which the polymer solution is passed through the filter X0 and filtered, the step X1 in which the polymer solution through the step X0 is passed through the filter X1 and filtered, and the step X1 in which the polymer solution through the step X1 is passed through the filter X2. [6] includes one or more steps of performing the above-mentioned step X0, the above-mentioned step X1 and the above-mentioned X2 on the polymer solution which has been subjected to the above-mentioned step X2 and includes the step X2 for filtering. The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to the above method.
[8] The actinic cheilitis according to [6] or [7], wherein the differential pressure of the filter X0, the differential pressure of the filter X1, and the differential pressure of the filter X2 are all 0.3 MPa or less. A method for producing a radiation-sensitive resin composition.
[9] Any of [1] to [8], wherein the resin that is decomposed by the action of the above acid and whose polarity is increased contains a resin containing a repeating unit derived from at least one of an acrylic acid ester and a methacrylic acid ester. The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to.
[10] The actinic cheilitis or radiation-sensitive resin according to any one of [1] to [9], wherein the resin whose polarity is increased by decomposition by the action of the acid contains one or more of a carbonate structure and a sultone structure. A method for producing a sex resin composition.
[11] Supported by using the sensitive light-sensitive or radiation-sensitive resin composition produced by the method for producing the sensitive light-sensitive or radiation-sensitive resin composition according to any one of [1] to [10]. The process of forming a resist film on the body and
The process of exposing the resist film and
A pattern forming method comprising a step of developing the exposed resist film with a developing solution.
[12] A method for manufacturing an electronic device, including the pattern forming method according to [11].

According to the present invention, it is possible to provide a method for producing a sensitive light-sensitive or radiation-sensitive resin composition capable of forming a pattern in which bridge defects are suppressed.
The present invention can also provide a pattern forming method using a sensitive light-sensitive or radiation-sensitive resin composition capable of forming a pattern in which bridge defects are suppressed, and a method for manufacturing an electronic device.

It is the schematic of the apparatus for demonstrating an example of embodiment of process A. It is the schematic of the apparatus for demonstrating an example of embodiment of process A. It is the schematic of the apparatus for demonstrating an example of embodiment of process A. It is the schematic of the apparatus for demonstrating an example of embodiment of process A.

Hereinafter, the present invention will be described in detail.
The description of the constituent elements described below may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
Regarding the notation of a group (atomic group) in the present specification, unless it is contrary to the gist of the present invention, the notation without substitution and non-substitution includes a group having a substituent as well as a group having no substituent. To do. For example, the "alkyl group" includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group). Further, the "organic group" in the present specification means a group containing at least one carbon atom.
Unless otherwise specified, the substituent is preferably a monovalent substituent.
As used herein, the term "active light" or "radiation" refers to, for example, the emission line spectrum of a mercury lamp, far ultraviolet rays typified by an excimer laser, extreme ultraviolet rays (EUV light: Extreme Ultraviolet), X-rays, and electron beams (EB). : Electron Beam) and the like. As used herein, "light" means active light or radiation.
Unless otherwise specified, the term "exposure" as used herein refers to not only exposure to the emission line spectrum of a mercury lamp, far ultraviolet rays represented by excimer lasers, extreme ultraviolet rays, X-rays, EUV light, etc., but also electron beams and It also includes drawing with particle beams such as ion beams.
In the present specification, "-" is used to mean that the numerical values described before and after it are included as the lower limit value and the upper limit value.
The bonding direction of the divalent group described in the present specification is not limited unless otherwise specified. For example, when Y is -COO- in the compound represented by the general formula "XYZ", Y may be -CO-O-, and is -O-CO-. You may. Moreover, the said compound may be "X-CO-O-Z" or "X-O-CO-Z".

In the present specification, (meth) acrylate represents acrylate and methacrylate, and (meth) acrylic represents acrylic and methacrylic.
In the present specification, the weight average molecular weight (Mw), the number average molecular weight (Mn), and the degree of dispersion (also referred to as molecular weight distribution) (Mw / Mn) of the resin are determined by a GPC (Gel Permeation Chromatography) apparatus (HLC-8120GPC manufactured by Toso). ) GPC measurement (solvent: tetrahydrofuran, flow rate (sample injection amount): 10 μL, column: TSK gel Multipore HXL-M manufactured by Toso Co., Ltd., column temperature: 40 ° C., flow velocity: 1.0 mL / min, detector: differential refractometer It is defined as a polystyrene-equivalent value by a detector (Refractive Index Detector).

In the present specification, the acid dissociation constant (pKa) represents pKa in an aqueous solution, and specifically, the following software package 1 is used to obtain a value based on a database of Hammett's substituent constants and known literature values. , It is a value obtained by calculation. All pKa values described herein indicate values calculated using this software package.

Software Package 1: Advanced Chemistry Development (ACD / Labs) Software V8.14 for Solaris (1994-2007 ACD / Labors).

In the present specification, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[Method for manufacturing sensitive light-sensitive or radiation-sensitive resin composition]
The method for producing the actinic or radiation-sensitive resin composition of the present invention (hereinafter, also referred to as “resist composition”) (hereinafter, also referred to as “the production method of the present invention”) is described in the following step A and the following. Includes step B.
Step A: A step of purifying a polymer solution containing a resin (hereinafter, also referred to as “acid-degradable resin”) whose polarity is increased by the action of an acid and a solvent, wherein the polymer solution is filtered through X. Includes step X of passing through and filtering.
Step B: A compound that generates an acid by irradiation with active light or radiation (hereinafter, also referred to as “photoacid generator”) is added to the polymer solution that has undergone the above step A to form a sensitive light-sensitive or radiation-sensitive resin. The process of adjusting things

In the production of a resist composition, filtration purification by filtering is generally carried out at the stage of preparing the resist composition.
Nowadays, the present inventor has performed filtration purification by filtering at a stage after preparation of a resist composition, in which impurities mixed with raw material components and brought into the resist composition (hereinafter, also referred to as “raw material-derived impurities”). Among them, impurities containing metal atoms (hereinafter, also referred to as “metal impurities”) and by-products (referred to as by-products) derived from acid-degradable resins include low molecular weight bodies, super molecular weight bodies, and gel components. It has been found that (.) Is not completely removed, and that this forms minute aggregates in the resist composition, which causes bridge defects on the pattern.
On the other hand, in the production method of the present invention, when preparing a resist composition containing an acid-degradable resin, a photoacid generator, and a solvent, first, a polymer solution containing the acid-degradable resin and a solvent is filtered. The amount of impurity components derived from the acid-degradable resin is reduced by performing purification according to the above, and a photoacid generator is added to the obtained polymer solution after purification. As a result, it is considered that the resist composition obtained by the production method of the present invention can reduce the number of minute aggregates generated in the resist composition and, by extension, suppress the bridge defects generated on the developed pattern. Be done. In particular, when the acid-decomposable resin contains one or more of a carbonate structure and a sultone structure, the effect of reducing specific metal impurities in step A is more excellent, and as a result, bridge defects generated on the developed pattern can be further suppressed. Is confirmed.

In the following, step A and step B included in the production method of the present invention will be described respectively.
[Step A]
Step A is a step of purifying a polymer solution containing an acid-decomposable resin and a solvent, and is a step X of passing the polymer solution through a filter X and filtering the polymer solution (hereinafter, also referred to as “step X”). including.

Step X is preferably carried out in a temperature environment of 15 to 25 ° C.

The material of the filter X is not particularly limited, and examples thereof include a polyamide resin, a polyolefin resin, and a fluororesin.
As the polyamide resin, nylon (nylons include nylon 6, nylon 66, nylon 46, and the like) is preferable.
As the polyolefin resin, polyethylene or polypropylene is preferable.
As the fluororesin, PTFE (polytetrafluoroethylene) is preferable.
As the material of the filter X, a polyamide resin or a polyolefin resin is particularly preferable. When the filter X is a polyamide resin film, it is considered that the amount of impurities in the polymer solution can be reduced by adsorbing impurities at the amide moiety in the resin. When the filter X is a polyolefin resin film, impurities are removed depending on the pore size thereof. The metal impurities contained in the impurities include by-products derived from acid-decomposable resins (examples of by-products include low molecular weight bodies, super molecular weight bodies, and gel components), and chemically and / or. It is presumed that most of them are removed from the polymer solution during filtering by physical adhesion.

The pore size of the filter X is not particularly limited, but from the viewpoint of filtration efficiency, for example, it is 0.5 μm or less, preferably 0.4 μm or less, and more preferably 0.3 μm or less. The lower limit of the pore diameter is not particularly limited, but is, for example, 0.001 μm or more. In the present specification, the "hole diameter" is intended to be the manufacturer's nominal diameter value.

Among the filters X, a nylon film having a pore diameter of 0.03 μm or less, a polyolefin resin film having a pore diameter of 0.01 μm or less, or a pore diameter of 0, in that bridge defects of the formed pattern are further suppressed. A fluororesin film of 01 μm or less is preferable.

The step A may include the step X once, or may include the step X twice or more.
When the step A includes the step X twice or more, the step A may be a one-time liquid passing method in which the polymer solution is passed once in a system in which two or more filters X are connected in series, or a filter. A circulation method may be used in which the polymer solution that has passed through X is further guided to the same filter and circulated in the closed system. The step A may be a method in which the one-time liquid passing method in which the polymer solution is passed once in a system in which two or more filters X are connected in series is repeated a plurality of times.

When the process A includes the process X twice or more, the number of times is not particularly limited, but for example, it is two times or more, preferably three times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less. In the case where the step A is performed by the circulation method, for example, when there is one filter X in the closed system, the number of times of circulation of the polymer solution is, for example, 2 times or more, preferably 3 times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less.

When the two or more steps X are carried out by the one-time liquid passing method, the plurality of filters X may be the same or different from each other. In addition, in this specification, "a plurality of filters are different" means that a plurality of filters have different pore diameters and / or materials.

In step X, the differential pressure of the filter X (intended to be a pressure loss before and after the filter X) is preferably 0.3 MPa or less. The lower limit is not particularly limited, but 0 MPa can be mentioned.

When the step A includes the step X more than once, the step A includes the following steps (1), (2), or (3) in that the bridge defect of the formed pattern is further suppressed. Is preferable.
Step (1): Includes a step X0 in which the polymer solution is passed through the filter X0 and filtered, and a step X1 in which the polymer solution that has passed through the step X0 is passed through the filter X1 and filtered.
Step (2): Includes a step X1 in which the polymer solution is passed through the filter X1 and filtered, and a step X2 in which the polymer solution that has passed through the step X1 is passed through the filter X2 and filtered.
Step (3): A step X0 in which the polymer solution is passed through the filter X0 and filtered, a step X1 in which the polymer solution through the step X0 is passed through the filter X1 and filtered, and the polymer solution through the step X1 is passed through the filter X2. It includes a step X2 of allowing and filtering.

Further, it is preferable that the steps (1) to (3) are carried out in a temperature environment of 15 to 25 ° C. Hereinafter, each step of steps (1) to (3) will be described in detail.

<Process (1)>
≪Process X0≫
The filter X0 is a filter different from the filter X1 used in the step X1 and is selected from a polyolefin resin film having a pore size of 0.01 μm or less and a fluororesin film having a pore size of 0.01 μm or less. There are no particular restrictions.
The lower limit of the pore size of the polyolefin resin film having a pore size of 0.01 μm or less is, for example, 0.001 μm or more. Further, as the polyolefin resin constituting the polyolefin resin film, polyethylene or polypropylene is preferable.
The lower limit of the pore size of the fluororesin film having a pore size of 0.01 μm or less is, for example, 0.001 μm or more. Further, as the fluororesin constituting the fluororesin film, PTFE is preferable.

≪Process X1≫
The filter X1 has the same meaning as the filter X used in the above-mentioned step X, and the preferred embodiment is also the same.
Further, the procedure of the step X1 is the same as the procedure of the above-mentioned step X.

In step X0 and step X1, the differential pressure of the filter X0 (intended to be a pressure loss before and after the filter X0) and the differential pressure of the filter X1 are preferably 0.3 MPa or less, respectively. The lower limit is not particularly limited, but 0 MPa can be mentioned.

The step A may include the step (1) once, or may include the step (1) twice or more. The case where the step A includes the step (1) twice or more means that the step A includes the step of performing the step X0 and the step X1 again once or more with respect to the polymer solution that has passed through the step X1. Intended.
When the step A includes the step (1) twice or more, the step (1) is a one-time process in which the polymer solution is passed once through a system in which the filter X0 and the filter X1 are connected alternately and in series in this order. A liquid passing method may be used, or a circulation method may be used in which the polymer solution that has passed through the filter X0 and the filter X1 in this order is further guided to the same filter X0 and circulated in the closed system.

When the step A includes the step (1) twice or more, the number of times is not particularly limited, but for example, it is two times or more, preferably three times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less. In the case where the step (1) is performed by the circulation method, for example, when the filter X0 and the filter X1 in the closed system are each one, the number of times of circulation of the polymer solution is, for example, two times or more, and three times or more. Is preferable. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less.

When the step (1) is carried out two or more times by the one-time liquid passing method, the plurality of filters X0 and the plurality of filters X1 may be the same or different from each other.

In the step (1), when the materials of the filter X0 and the filter X1 are different, the filter X0 is a polyolefin resin and the filter X1 is a polyamide resin. Further, when the pore diameters of the filter X0 and the filter X1 are different in the step (1), it is preferable that the pore diameter of the filter X0 is larger than the pore diameter of the filter X1. The difference between the pore diameter of the filter X1 and the pore diameter of the filter X0 is preferably, for example, 0.001 to 0.2 μm.

<Process (2)>
≪Process X1≫
The filter X1 has the same meaning as the filter X used in the above-mentioned step X, and the preferred embodiment is also the same.
Further, the procedure of the step X1 is the same as the procedure of the above-mentioned step X.

≪Process X2≫
The filter X2 is a filter different from the filter X1 used in the step X1 and is selected from a polyolefin resin film having a pore size of 0.01 μm or less and a fluororesin film having a pore size of 0.01 μm or less. There are no particular restrictions.
The lower limit of the pore size of the polyolefin resin film having a pore size of 0.01 μm or less is, for example, 0.001 μm or more. Further, as the polyolefin resin constituting the polyolefin resin film, polyethylene or polypropylene is preferable.
The lower limit of the pore size of the fluororesin film having a pore size of 0.01 μm or less is, for example, 0.001 μm or more. Further, as the fluororesin constituting the fluororesin film, PTFE is preferable.

In step X1 and step X2, the differential pressure of the filter X1 and the differential pressure of the filter X2 (intended to be a pressure loss before and after the filter X2) are preferably 0.3 MPa or less, respectively. The lower limit is not particularly limited, but 0 MPa can be mentioned.

The step A may include the step (2) once, or may include the step (2) twice or more. The case where the step A includes the step (2) twice or more means that the step A includes a step of performing the step X1 and the step X2 once or more with respect to the polymer solution that has passed through the step X2. Intended.
When the step A includes the step (2) more than once, the step (2) is a one-time process in which the polymer solution is passed once through a system in which the filter X1 and the filter X2 are connected alternately and in series in this order. A liquid passing method may be used, or a circulation method may be used in which the polymer solution that has passed through the filter X1 and the filter X2 in this order is further guided to the same filter X1 and circulated in the closed system.

When the step A includes the step (2) twice or more, the number of times is not particularly limited, but for example, it is two times or more, preferably three times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less. In the case where the step (2) is performed by the circulation method, for example, when the filter X1 and the filter X2 in the closed system are each one, the number of times of circulation of the polymer solution is, for example, two or more, and three or more times. Is preferable. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less.

When the step (2) of two or more times is carried out by the one-time liquid passing method, the plurality of filters X1 and the plurality of filters X2 may be the same or different from each other.

In the step (2), when the materials of the filter X1 and the filter X2 are different, the filter X1 is a polyamide resin and the filter X2 is a polyolefin resin. Further, when the pore diameters of the filter X1 and the filter X2 are different in the step (2), it is preferable that the pore diameter of the filter X1 is larger than the pore diameter of the filter X2. The difference between the pore diameter of the filter X2 and the pore diameter of the filter X1 is preferably, for example, 0.001 to 0.2 μm.

<Process (3)>
≪Process X0≫
Step X0 has the same meaning as step X0 in the above-mentioned step (1), and the preferred embodiment is also the same.

≪Process X2≫
The step X2 is a step of passing the polymer solution that has undergone the step X1 through the filter X2 and filtering, and is the same as the step X2 in the above-mentioned step (2) except that the target of filtration and purification is the polymer solution that has passed through the step X1. The same is true, and the preferred embodiment is also the same.

In step X0, step X1, and step X2, the differential pressure of the filter X0, the differential pressure of the filter X1, and the differential pressure of the filter X2 are preferably 0.3 MPa or less, respectively. The lower limit is not particularly limited, but 0 MPa can be mentioned.

The step A may include the step (3) once, or may include the step (3) twice or more. When the step A includes the step (3) twice or more, it means that the step X0, the step X1 and the step X2 are performed once or more with respect to the polymer solution that has undergone the step X2. Intended.
When step A includes step (3) more than once, step (3) passes the polymer solution once in a system in which filter X0, filter X1 and filter X2 are connected alternately and in series in this order. It may be a one-time liquid passing method in which the polymer solution is passed through the filter X0, the filter X1 and the filter X2 in this order, and the polymer solution is further guided to the same filter X0 and circulated in the closed system.

When the step A includes the step (3) twice or more, the number of times is not particularly limited, but for example, it is two times or more, preferably three times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less. When the step (3) is performed by the circulation method, for example, when there is one filter X0, one filter X1 and one filter X2 in the closed system, the number of circulations of the polymer solution is, for example, two or more. It is preferably 3 times or more. The upper limit is not particularly limited, but is, for example, 15 times or less, preferably 10 times or less.

When the step (3) is carried out two or more times by the one-time liquid passing method, the plurality of filters X0, the plurality of filters X1, and the plurality of filters X2 may be the same or different. You may be.

In the step (3), when the materials of the filter X0 and the filter X1 are different, the filter X0 is a polyolefin resin or a fluororesin, and the filter X1 is a polyamide resin. Further, when the pore diameters of the filter X0 and the filter X1 are different in the step (3), it is preferable that the pore diameter of the filter X0 is larger than the pore diameter of the filter X1. The difference between the pore diameter of the filter X1 and the pore diameter of the filter X0 is preferably, for example, 0.001 to 0.2 μm.
In the step (3), when the materials of the filter X1 and the filter X2 are different, the filter X1 is a polyamide resin and the filter X2 is a polyolefin resin or a fluororesin. Further, when the pore diameters of the filter X1 and the filter X2 are different in the step (3), it is preferable that the pore diameter of the filter X1 is larger than the pore diameter of the filter X2. The difference between the pore diameter of the filter X2 and the pore diameter of the filter X1 is preferably, for example, 0.001 to 0.2 μm.
Further, in the step (3), it is preferable that the filter X0 and the filter X2 are made of different materials. Further, it is preferable that the pore diameter is larger in the order of the filter X2, the filter X1, and the filter 0.

<Other optional processes>
The production method of the present invention may optionally include other steps other than step A and step B.
Examples of the other step include step Z (hereinafter, also referred to as “step Z”) for measuring the content of metal impurities (impurities containing metal atoms) that can be contained in the polymer solution obtained through step A. .. The "metal impurities" are intended as metal ions and impurities contained in the polymer solution as solids (including simple metals and particulate metal-containing compounds).
In the semiconductor device manufacturing process, it is required to reduce metal impurities in the resist composition. The type of the metal atom in the metal impurity is not particularly limited, but examples of the metal whose content in the resist composition is desired to be small include Na, K, Ca, Fe, Cu, Mg, Mn, and Al. Each metal atom such as Li, Cr, Ni, Sn, Zn, Ag, As, Au, Ba, Cd, Co, Pb, V, W, Zr, and Mo (hereinafter, also referred to as "specific metal atom") is mentioned. Be done.
In the present specification, the content of metal impurities in the polymer solution is intended to be the content of metal atoms measured by ICP-MS (inductively coupled plasma mass spectrometry). The method for measuring the content of metal atoms using ICP-MS is as described in Examples described later.

The content of each metal atom (particularly the specific metal atom) is preferably 100 mass ppb or less, more preferably 50 mass ppb or less, further preferably 20 mass ppb or less, and particularly preferably 10 mass ppb, based on the total mass of the solution. Preferably, 5.0 mass ppb or less is most preferable, and 1.0 mass ppb or less is more preferable. The lower limit of the content of each metal atom is preferably not substantially contained (below the detection limit of the measuring device), and more preferably 0.
Further, the total content of the specific metal atom in the polymer solution is preferably 100 mass ppb or less, more preferably 50 mass ppb or less, further preferably 20 mass ppb or less, and 10 mass ppb with respect to the total mass of the solution. Particularly preferably, 5.0 mass ppb or less is most preferable, and 1.0 mass ppb or less is more preferable. The lower limit of the total content of the specific metal atom is preferably not substantially contained (below the detection limit of the measuring device), and more preferably 0.

In the following, an example of the embodiment of step A will be described with reference to the drawings. 1 to 4 are schematic views of the apparatus used in step A.

The device of FIG. 1 is a device used when the step A is a mode in which the step X is carried out by a one-time liquid passing method only once.
In the device of FIG. 1, the tank 1, the pump 2, and the column 100 on which the filter X is installed are connected by flow paths 5 to 7. Further, a flow meter 3 and a filling port 8 are installed in the flow path 7. By driving the pump 2, the polymer solution filled in the tank 1 passes through the column 100 in which the filter X is installed, and the polymer solution that has passed through the column 100 is filled in the treatment liquid filling container 4.

The device of FIG. 2 is a device used when step A is a mode in which step X is performed two or more times in a circulation manner.
In the device of FIG. 2, the tank 1, the pump 2, and the column 100 on which the filter X is installed are connected by flow paths 5 to 7.
Further, the flow path 7 is also connected to the tank 1, and by driving the pump 2, the polymer solution contained in the tank 1 is circulated in the system. Further, a filling port 8 is provided in the flow path 7, and the polymer solution that has undergone a predetermined circulation filtration step is filled in the treatment liquid filling container 4.
Here, the filling port 8 is often closed at the start of driving the pump so that a predetermined number of circulations can be achieved.
The number of circulations can be calculated using the flow meter 3 installed in the flow path 7.

The device of FIG. 3 is a device used when the step A is a mode in which the step (3) is carried out by a one-time liquid passing method only once.
In the apparatus of FIG. 3, the tank 1, the pump 2, the column 200 in which the filter X0 is installed, the column 300 in which the filter X1 is installed, and the column 400 in which the filter X2 is installed are the

flow paths

5, 6, 7, and 9. , And 10 are connected. Further, a flow meter 3 and a filling port 8 are installed in the flow path 7. By driving the pump 2, the polymer solution filled in the tank 1 passes through the column 200, the column 300, and the column 400, and the polymer solution that has passed through the column 400 is filled in the treatment liquid filling container 4.

The device of FIG. 4 is a device used when the step A is an embodiment in which the step (3) is carried out in a circulation manner.
In the apparatus of FIG. 4, the tank 1, the pump 2, the column 500 in which the filter X0 is installed, the column 600 in which the filter X1 is installed, and the column 700 in which the filter X2 is installed are the

flow paths

5, 6, 7, and 9. , And 10 are connected.
Further, the flow path 7 is also connected to the tank 1, and by driving the pump 2, the polymer solution contained in the tank 1 is circulated in the system. Further, a filling port 8 is provided in the flow path 7, and the polymer solution that has undergone a predetermined circulation filtration step is filled in the treatment liquid filling container 4.
Here, the filling port 8 is often closed at the start of driving the pump so that a predetermined number of circulations can be achieved.
The number of circulations can be calculated using the flow meter 3 installed in the flow path 7.

<Polymer solution>
Next, the polymer solution will be described.
The polymer solution contains an acid-degradable resin and a solvent.
It is preferable that the polymer solution does not substantially contain a compound (photoacid generator) that generates an acid by irradiation with active light or radiation. Here, "the polymer solution substantially does not contain the photoacid generator" means that the content of the photoacid generator is 3.0% by mass or less with respect to the total mass of the polymer solution. , 2.0% by mass or less is preferable, and 1.0% by mass or less is more preferable.
Among them, the polymer solution preferably contains substantially no other components other than the acid-decomposable resin and the solvent. Here, "the polymer solution substantially does not contain other components other than the acid-degradable resin and the solvent" means that the total content of the acid-decomposable resin and other components other than the solvent is the total content of the polymer solution. It is intended to be 3.0% by mass or less with respect to the total mass, preferably 2.0% by mass or less, and more preferably 1.0% by mass or less.

(Acid-degradable resin (resin (A)))
The polymer solution contains a resin (“acid-decomposable resin” or “resin (A)”) that is decomposed by the action of an acid to increase its polarity.
The acid-degradable resin usually contains a repeating unit having a group (hereinafter, also referred to as “acid-degradable group”) that decomposes by the action of an acid to increase its polarity.
In the pattern forming method of the present invention, typically, when an alkaline developer is used as the developer, a positive pattern is preferably formed, and when an organic developer is used as the developer, a negative pattern is preferable. Is formed in.

-Repeating unit having an acid-decomposable group The resin (A) preferably contains a repeating unit having an acid-decomposable group (hereinafter, also referred to as "repeating unit A").
The acid-degradable group preferably contains a structure in which a polar group is protected by a group (leaving group) that is decomposed and eliminated by the action of an acid.
Polar groups include carboxy group, phenolic hydroxyl group, fluorinated alcohol group, sulfonic acid group, sulfonamide group, sulfonylimide group, (alkylsulfonyl) (alkylcarbonyl) methylene group, (alkylsulfonyl) (alkylcarbonyl) imide group. , Bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, tris (alkylsulfonyl) methylene group, etc. (A group that dissociates in a 2.38 mass% tetramethylammonium hydroxide aqueous solution), an alcoholic hydroxyl group, and the like.

The alcoholic hydroxyl group is a hydroxyl group bonded to a hydrocarbon group and refers to a hydroxyl group other than the hydroxyl group directly bonded on the aromatic ring (phenolic hydroxyl group), and the α-position of the hydroxyl group is electron attraction such as a fluorine atom. Excludes aliphatic alcohols substituted with sex groups (eg, hexafluoroisopropanol groups, etc.). As the alcoholic hydroxyl group, a hydroxyl group having a pKa (acid dissociation constant) of 12 to 20 is preferable.

As the polar group, a carboxy group, a phenolic hydroxyl group, a fluorinated alcohol group (preferably a hexafluoroisopropanol group), or a sulfonic acid group is preferable.

A preferable group as an acid-degradable group is a group in which the hydrogen atom of these groups is replaced with a group (leaving group) that is eliminated by the action of an acid.
Examples of the group (leaving group) desorbed by the action of an acid include -C (R ₃₆ ) (R ₃₇ ) (R ₃₈ ), -C (R ₃₆ ) (R ₃₇ ) (OR ₃₉ ), and-. Examples thereof include C (R ₀₁ ) (R ₀₂ ) (OR ₃₉ ).
In the formula, R ₃₆ to R ₃₉ each independently represent an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group. R ₃₆ and R ₃₇ may be combined with each other to form a ring.
R ₀₁ and R ₀₂ each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group, or an alkenyl group.

The alkyl groups of R ₃₆ to R ₃₉ , R ₀₁ and R ₀₂ are preferably alkyl groups having 1 to 8 carbon atoms, for example, methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group and hexyl. Groups, octyl groups and the like can be mentioned.
The cycloalkyl groups of R ₃₆ to R ₃₉ , R ₀₁ , and R ₀₂ may be monocyclic or polycyclic. The monocyclic ring is preferably a cycloalkyl group having 3 to 8 carbon atoms, and examples thereof include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. As the polycycle, a cycloalkyl group having 6 to 20 carbon atoms is preferable, and for example, an adamantyl group, a norbornyl group, an isobornyl group, a camphanyl group, a dicyclopentyl group, an α-pinel group, a tricyclodecanyl group and a tetracyclododecyl group , And androstanyl groups and the like. In addition, one or more carbon atoms in the cycloalkyl group may be substituted with a hetero atom such as an oxygen atom.
The aryl group of R ₃₆ to R ₃₉ , R ₀₁ , and R ₀₂ is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.
The aralkyl group of R ₃₆ to R ₃₉ , R ₀₁ , and R ₀₂ is preferably an aralkyl group having 7 to 12 carbon atoms, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.
The alkenyl group of R ₃₆ to R ₃₉ , R ₀₁ , and R ₀₂ is preferably an alkenyl group having 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a butenyl group, and a cyclohexenyl group.
A cycloalkyl group (monocyclic or polycyclic) is preferable as the ring formed by bonding R ₃₆ and R ₃₇ to each other. The monocyclic cycloalkyl group is preferably a cyclopentyl group or a cyclohexyl group, and the polycyclic cycloalkyl group is preferably a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, an adamantyl group or the like.

As the acid-degradable group, a tertiary alkyl ester group, an acetal group, a cumyl ester group, an enol ester group, or an acetal ester group is preferable, and an acetal group or a tertiary alkyl ester group is more preferable.

The resin (A) preferably contains a repeating unit represented by the following general formula (AI) as the repeating unit A.

In the general formula (AI), T represents a single bond or a divalent linking group.
Examples of the divalent linking group of T include an alkylene group, an arylene group, -COO-Rt-, and -O-Rt-. In the formula, Rt represents an alkylene group, a cycloalkylene group, or an arylene group.
T is preferably single bond or -COO-Rt-. Rt is preferably a chain alkylene group having 1 to 5 carbon atoms, and more preferably −CH _2- , − (CH ₂ ) _2- , or − (CH ₂ ) _3- .
More preferably, T is a single bond.

In the general formula (AI), Xa ₁ represents a hydrogen atom, a halogen atom, or a monovalent organic group.
Xa ₁ is preferably a hydrogen atom or an alkyl group.
The alkyl group of Xa ₁ may have a substituent, and examples of the substituent include a hydroxyl group and a halogen atom (preferably a fluorine atom).
The alkyl group of Xa ₁ preferably has 1 to 4 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, and a trifluoromethyl group. The alkyl group of Xa ₁ is preferably a methyl group.

In the general formula (AI), Rx ₁ to Rx ₃ independently represent an alkyl group or a cycloalkyl group, respectively.
Any two of Rx ₁ to Rx ₃ may or may not be combined to form a ring structure.
The alkyl groups of Rx ₁ , Rx ₂ , and Rx ₃ may be linear or branched, and may be a methyl group, an ethyl group, an n-propyl group, an isopropyl group, or an n-butyl group. , Isobutyl group, t-butyl group and the like are preferable. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 to 3. The alkyl groups of Rx ₁ , Rx ₂ , and Rx ₃ may have a part of the carbon-carbon bond as a double bond.
The cycloalkyl groups of Rx ₁ , Rx ₂ , and Rx ₃ may be monocyclic or polycyclic. Examples of the monocyclic cycloalkyl group include a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic cycloalkyl group include a norbornyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, an adamantyl group and the like.

The ring formed by combining Rx ₁ , Rx ₂ , and Rx ₃ may be monocyclic or polycyclic. Examples of monocyclic rings include monocyclic cycloalkane rings such as cyclopentyl ring, cyclohexyl ring, cycloheptyl ring, and cyclooctane ring. Examples of polycycles include polycyclic cycloalkyl rings such as norbornane ring, tetracyclodecane ring, tetracyclododecane ring, and adamantane ring. Of these, a cyclopentyl ring, a cyclohexyl ring, or an adamantane ring is preferable.
Further, as the ring formed by combining Rx ₁ , Rx ₂ , and Rx ₃ , the ring shown below is also preferable.

Specific examples of the monomers corresponding to the repeating units represented by the general formula (AI) will be given below. The following specific example corresponds to the case where Xa ₁ in the general formula (AI) is a methyl group, but Xa ₁ can be arbitrarily substituted with a hydrogen atom, a halogen atom, or a monovalent organic group.

It is also preferable that the resin (A) has the repeating unit described in paragraphs [0336] to [0369] of US Patent Application Publication No. 2016/0070167A1 as the repeating unit A.

Further, the resin (A), as a repeating unit A, contains a group that is decomposed by the action of an acid described in paragraphs [0363] to [0364] of US Patent Application Publication No. 2016/0070167A1 to generate an alcoholic hydroxyl group. It may have a repeating unit that includes.

The resin (A) may contain the repeating unit A alone or in combination of two or more.

The content of the repeating unit A contained in the resin (A) (if there are a plurality of repeating units A, the total thereof) is preferably 10 to 90 mol%, preferably 20 to 90 mol%, based on all the repeating units of the resin (A). 80 mol% is more preferable, 30 to 80 mol% is further preferable, and 35 to 80 mol% is particularly preferable.

-The repeating unit resin (A) having at least one selected from the group consisting of a lactone structure, a sultone structure, and a carbonate structure includes a structure selected from the group consisting of a lactone structure, a sultone structure, and a carbonate structure. More preferably, it contains a repeating unit having at least one selected from the group consisting of a lactone structure, a sultone structure, and a carbonate structure (hereinafter, also referred to as “repeating unit B”).
The resin (A) preferably contains one or more of a sultone structure and a carbonate structure in that bridge defects of the formed pattern are more suppressed, and the repeating unit B is a repeating unit having a sultone structure. More preferably, it comprises at least one of a unit and a repeating unit having a carbonate structure.

The lactone structure or sultone structure may have a lactone ring or a sultone ring, and a lactone structure having a 5- to 7-membered lactone ring or a sultone structure having a 5- to 7-membered sultone ring is preferable.
A lactone structure in which a 5- to 7-membered ring lactone ring is fused with another ring to form a bicyclo structure or a spiro structure is also preferable. A sultone structure in which another ring is fused to a 5- to 7-membered sultone ring in the form of forming a bicyclo structure or a spiro structure is also preferable.

Among them, the resin (A) has a lactone structure represented by any of the following general formulas (LC1-1) to (LC1-22), or any of the following general formulas (SL1-1) to (SL1-3). It is preferable to include a repeating unit having a sultone structure represented by. Further, the lactone structure or the sultone structure may be directly bonded to the main chain.
Among them, general formula (LC1-1), general formula (LC1-4), general formula (LC1-5), general formula (LC1-8), general formula (LC1-16), general formula (LC1-21) Alternatively, a lactone structure represented by the general formula (LC1-22) or a sultone structure represented by the general formula (SL1-1) is preferable.

The lactone structure or sultone structure may or may not have a substituent (Rb ₂ ). Examples of the substituent (Rb ₂ ) include an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 4 to 7 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, and a carboxy group. A halogen atom, a hydroxyl group, a cyano group or the like is preferable, and an alkyl group having 1 to 4 carbon atoms or a cyano group is more preferable. n ₂ represents an integer from 0 to 4. When n ₂ is 2 or more, the plurality of substituents (Rb ₂ ) may be the same or different. Further, a plurality of existing substituents (Rb ₂ ) may be bonded to each other to form a ring.

As the repeating unit having a lactone structure or a sultone structure, a repeating unit represented by the following general formula (III) is preferable.

In the above general formula (III),
A represents -COO- or -CONH-.

n is the number of repetitions of the structure represented by −R ₀ −Z−, represents an integer of 0 to 5, is preferably 0 or 1, and more preferably 0. When n is 0, (-R _0- Z-) n is a single bond.

R ₀ represents an alkylene group, a cycloalkylene group, or a combination thereof. When there are a plurality of R _0s , the plurality of R _0s may be the same or different.
The alkylene group represented by R ₀ may be either linear or branched. The carbon number of the alkylene group represented by R ₀ is, for example, 1 to 12, preferably 1 to 10, and more preferably 1 to 6.
The cycloalkylene group represented by R ₀ may be either monocyclic or polycyclic. The carbon number of the cycloalkylene group represented by R ₀ is, for example, 1 to 12, preferably 1 to 10, and more preferably 1 to 6. Examples of the cycloalkane constituting the cycloalkylene group represented by R ₀ include a monocyclic cycloalkane ring such as a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring, and a norbornane ring and a tetracyclodecane ring. , A tetracyclododecane ring, and a polycyclic cycloalkane ring such as an adamantan ring.
The alkylene group or cycloalkylene group of R ₀ may have a substituent. The substituent is not particularly limited, and for example, an alkyl group having 1 to 8 carbon atoms (either linear or branched chain) and a cycloalkyl group having 4 to 7 carbon atoms (monocyclic or polycyclic) are used. Any of them may be used), and examples thereof include an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a carboxy group, a halogen atom, a hydroxyl group, and a cyano group.

Z represents a single bond, -O-, -COO-, -CONH-, -NH-CO-O-, or -NH-CO-NH-. When there are a plurality of Z's, the plurality of Z's may be the same or different.
Among them, Z is preferably -O- or -COO-, and more preferably -COO-.

R ₈ represents a monovalent organic group having a lactone structure or a sultone structure.
Among them, in any of the structures represented by the general formulas (LC1-1) to (LC1-22) and the structures represented by the general formulas (SL1-1) to (SL1-3), the lactone structure or the sultone It is preferable that the group is formed by removing one hydrogen atom from one carbon atom constituting the structure. It is preferable that the carbon atom from which one hydrogen atom is removed is not a carbon atom constituting a substituent (Rb ₂ ).

R ₇ represents a hydrogen atom, a halogen atom, or a monovalent organic group (preferably a methyl group).
Examples of the organic group represented by R ₇ include an alkyl group having 1 to 8 carbon atoms (either linear or branched chain), and a methyl group is preferable.

Hereinafter, a monomer corresponding to a repeating unit having at least one selected from the group consisting of a lactone structure and a sultone structure will be illustrated.
In the examples below, the methyl group attached to the vinyl group may be replaced with a hydrogen atom, a halogen atom, or a monovalent organic group.

The resin (A) may have a repeating unit having a carbonate structure. As the carbonate structure, a cyclic carbonate structure is preferable.
As the repeating unit having a cyclic carbonate structure, a repeating unit represented by the following general formula (A-1) is preferable.

In the general formula (A-1), _RA ¹ represents a hydrogen atom, a halogen atom, or a monovalent organic group.
Examples of the monovalent organic group represented by _RA ¹ include an alkyl group having 1 to 6 carbon atoms which may have a substituent, and a methyl group is preferable. Examples of the substituent include a halogen atom and a hydroxyl group.
n represents an integer greater than or equal to 0.
R _A ² represents a substituent. when n is 2 or more, R _A ² existing in plural, may each be the same or different. The substituent is not particularly limited, and for example, an alkyl group having 1 to 8 carbon atoms (either linear or branched chain) and a cycloalkyl group having 4 to 7 carbon atoms (monocyclic or polycyclic) are used. Any of them may be used), and examples thereof include an alkoxy group having 1 to 8 carbon atoms, an alkoxycarbonyl group having 2 to 8 carbon atoms, a carboxy group, a halogen atom, a hydroxyl group, and a cyano group.
A represents a single bond or a divalent linking group.
The divalent linking group represented by A is not particularly limited, but for example, -CO-, -O-, -S-, -SO-, -SO _2- , -NH-, and an alkylene group (preferably carbon). Numbers 1 to 6), a cycloalkylene group (preferably having 3 to 15 carbon atoms), an alkenylene group (preferably having 2 to 6 carbon atoms), and a divalent linking group obtained by combining a plurality of these groups can be mentioned. Among these, an alkylene group (preferably having 1 to 6 carbon atoms) which may contain -CO- and -O- is more preferable.
Z represents an atomic group forming a monocyclic or polycyclic ring with a group represented by —O—CO—O— in the formula. As Z, an atomic group forming a monocycle with a group represented by —O—CO—O— in the formula is preferable, and the number of ring members of the monocycle is preferably 5 to 6, and more preferably 5.

It is also preferable that the resin (A) has the repeating unit described in paragraphs [0370] to [0414] of US Patent Application Publication No. 2016/0070167A1 as the repeating unit B.

The repeating unit B may be contained alone or in combination of two or more.

The content of the repeating unit B contained in the resin (A) (if there are a plurality of repeating units B, the total thereof) is preferably 5 to 70 mol% with respect to all the repeating units in the resin (A). From 20 to 65 mol% is more preferable, 20 to 65 mol% is further preferable, and 20 to 60 mol% is particularly preferable.
Among them, the content of the repeating unit having a sultone structure and the repeating unit having a carbonate structure contained in the resin (A) (the total of the repeating units if a plurality of them exist) is based on all the repeating units in the resin (A). 10 to 65 mol% is more preferable, 10 to 60 mol% is further preferable, and 10 to 55 mol% is particularly preferable.

-Repeating unit having a polar group The resin (A) preferably contains a repeating unit having a polar group (hereinafter, also referred to as "repeating unit C").
Examples of the polar group include a hydroxyl group, a cyano group, a carboxy group, a fluorinated alcohol group (for example, a hexafluoroisopropanol group) and the like.
As the repeating unit C, a repeating unit having an alicyclic hydrocarbon structure substituted with a polar group is preferable. In the alicyclic hydrocarbon structure substituted with a polar group, the alicyclic hydrocarbon structure is preferably a cyclohexyl group, an adamantyl group, or a norbornane group.

Specific examples of the monomer corresponding to the repeating unit C are given below, but the present invention is not limited to these specific examples.

In addition, as a specific example of the repeating unit C, the repeating unit disclosed in paragraphs [0415] to [0433] of the US Patent Application Publication No. 2016/0070167A1 can be mentioned.
The resin (A) may have one type of repeating unit C alone, or may contain two or more types in combination.

When the resin (A) contains the repeating unit C, the content of the repeating unit C (if there are a plurality of repeating units C, the total thereof) is 5 to 60 mol with respect to all the repeating units in the resin (A). % Is preferred, 5 to 30 mol% is more preferred, and 5 to 15 mol% is even more preferred.

-Repeating unit having neither an acid-decomposable group nor a polar group The resin (A) is further referred to as a repeating unit having neither an acid-decomposable group nor a polar group (hereinafter, also referred to as "repeating unit D". ) May be included.
The repeating unit D preferably has an alicyclic hydrocarbon structure. Examples of the repeating unit D include the repeating unit described in paragraphs [0236] to [0237] of US Patent Application Publication No. 2016/0026083A1.
A preferred example of the monomer corresponding to the repeating unit D is shown below.

Other specific examples of the repeating unit D include the repeating unit disclosed in paragraph [0433] of US Patent Application Publication No. 2016/0070167A1.
The resin (A) may contain the repeating unit D alone or in combination of two or more.
When the resin (A) contains the repeating unit D, the content of the repeating unit D (if there are a plurality of repeating units D, the total thereof) is 5 to 40 mol with respect to all the repeating units in the resin (A). % Is preferable, 5 to 30 mol% is more preferable, 5 to 25 mol% is further preferable, and 5 to 15 mol% is particularly preferable.

In addition to the above repeating units, the resin (A) has dry etching resistance, standard developer suitability, substrate adhesion, resist profile, or resolution which is a general necessary property of resist. It may have various repeating units for the purpose of adjusting heat resistance, sensitivity and the like.
Examples of such a repeating unit include, but are not limited to, a repeating unit corresponding to a predetermined monomer.

The predetermined monomer has one addition-polymerizable unsaturated bond selected from, for example, acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters and the like. Examples include compounds.
In addition, an addition-polymerizable unsaturated compound that can be copolymerized with the monomers corresponding to the various repeating units may be used.
In the resin (A), the molar ratio of each repeating unit is appropriately set in order to adjust various performances.

The resin (A) preferably contains a repeating unit derived from at least one of an acrylic acid ester and a methacrylic acid ester. When the resin (A), which is an acid-degradable resin, has a structure containing a repeating unit derived from at least one of an acrylic acid ester and a methacrylic acid ester, a supermolecular weight substance and a gel component are added to the by-products generated in the manufacturing process. Many can be included. Therefore, when the resin (A), which is an acid-degradable resin, has a structure containing a repeating unit derived from at least one of an acrylic acid ester and a methacrylic acid ester, the effect of the production method of the present invention is more excellent. You can enjoy it.

When the polymer solution is for ArF exposure, the number of repeating units having an aromatic group is preferably 15 mol% or less with respect to all the repeating units in the resin (A) from the viewpoint of the transmission of ArF light. More preferably, it is 10 mol% or less.

When the polymer solution is for ArF exposure, it is preferable that all the repeating units of the resin (A) are composed of (meth) acrylate-based repeating units. That is, the resin (A) is preferably a resin composed of repeating units derived from at least one of an acrylic acid ester and a methacrylic acid ester. In this case, all of the repeating units are methacrylate-based repeating units, all of the repeating units are acrylate-based repeating units, and all of the repeating units are either methacrylate-based repeating units or acrylate-based repeating units. Although it can be used, the acrylate-based repeating unit is preferably 50 mol% or less based on all the repeating units of the resin (A).

When the polymer solution is for KrF exposure, EB exposure, or EUV exposure, the resin (A) preferably has a repeating unit having an aromatic hydrocarbon ring group, and a repeating unit having a phenolic hydroxyl group, or It is more preferable to include a repeating unit having a structure protected by a leaving group (acid-degradable group) in which the phenolic hydroxyl group is decomposed and eliminated by the action of an acid. Examples of the repeating unit containing a phenolic hydroxyl group include a hydroxystyrene repeating unit and a hydroxystyrene (meth) acrylate repeating unit.
When the polymer solution is for KrF exposure, EB exposure, or EUV exposure, the content of the repeating unit having an aromatic hydrocarbon ring group contained in the resin (A) is the total repetition in the resin (A). It is preferably 30 mol% or more with respect to the unit. The upper limit is not particularly limited, but is, for example, 100 mol% or less. Among them, 30 to 100 mol% is preferable, 40 to 100 mol% is more preferable, and 50 to 100 mol% is further preferable.

As the resin (A), for example, the resin (A) described in International Publication No. 2017/05/7253 and the like can be appropriately used.

The weight average molecular weight of the resin (A) is preferably 1,000 to 200,000, more preferably 2,000 to 20,000, and even more preferably 3,000 to 20,000. The degree of dispersion (Mw / Mn) is usually 1.0 to 3.0, preferably 1.0 to 2.6, more preferably 1.0 to 2.0, and further 1.1 to 2.0. preferable.

(solvent)
The polymer solution contains a solvent.
As the solvent, a known resist solvent can be appropriately used. For example, paragraphs [0665] to [0670] of U.S. Patent Application Publication No. 2016/0070167A1, paragraphs [0210] to [0235] of U.S. Patent Application Publication No. 2015/0004544A1, U.S. Patent Application Publication No. 2016/0237190A1. Known solvents disclosed in paragraphs [0424] to [0426] of the specification and paragraphs [0357] to [0366] of US Patent Application Publication No. 2016/0274458A1 can be preferably used.
Examples of the solvent include alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, lactate alkyl ester, alkyl alkoxypropionate, cyclic lactone (preferably having 4 to 10 carbon atoms), and a monoketone compound which may have a ring. (Preferably, the number of carbon atoms is 4 to 10), organic solvents such as alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate are mentioned, and alkylene glycol monoalkyl ether carboxylate is preferable, and propylene glycol monomethyl ether acetate is more preferable.
Further, as the organic solvent, one type may be used alone or two or more types may be used in combination, but it is preferable to use one type alone. When a mixed solvent in which two or more kinds of organic solvents are used in combination is used, a mixed solvent in which a solvent having a hydroxyl group in the structure and a solvent having no hydroxyl group are mixed is preferable.

The solid content concentration of the polymer solution is preferably 1.0 to 50% by mass, more preferably 2.0 to 40% by mass, and even more preferably 5.0 to 30% by mass. The solid content concentration is the mass percentage of the mass of the components excluding the solvent with respect to the total mass of the polymer solution.

[Step B]
In step B, a compound that generates an acid by irradiation with active light or radiation (photoacid generator) is added to the polymer solution that has undergone the above step A, and a sensitive light-sensitive or radiation-sensitive resin composition (hereinafter, “resist”) is added. This is a step of adjusting (also referred to as "composition").
In the following, first, the actinic light-sensitive or radiation-sensitive resin composition obtained through step B will be described.

<Acid-degradable resin (resin (A))>
The resist composition contains an acid-decomposable resin (resin (A)) derived from the above-mentioned polymer solution. The acid-decomposable resin (resin (A)) is as described above.

The resin (A) may be used alone or in combination of two or more.
The content of the resin (A) in the resist composition is generally 20.0% by mass or more, preferably 40.0% by mass or more, and 60.0% by mass, based on the total solid content. The above is more preferable, and 70.0% by mass or more is further preferable. The upper limit is not particularly limited, but 99.5% by mass or less is preferable, 99.0% by mass or less is more preferable, and 97.0% by mass or less is further preferable. The solid content is intended to be a component in the composition excluding the solvent, and any component other than the solvent is regarded as a solid content even if it is a liquid component.

<Photoacid generator (B)>
The resist composition contains a compound that generates an acid by irradiation with active light or radiation (hereinafter, also referred to as “photoacid generator (B)”).
The photoacid generator (B) referred to here is an acid generator usually used to cause a deprotection reaction of a resin component (a deprotection reaction of an acid-degradable resin) or to cause a cross-linking reaction of a resin component. The agent is applicable.
As the photoacid generator (B), a compound that generates an organic acid by irradiation with active light or radiation is preferable. Examples thereof include sulfonium salt compounds, iodonium salt compounds, diazonium salt compounds, phosphonium salt compounds, imide sulfonate compounds, oxime sulfonate compounds, diazodisulfone compounds, disulfone compounds, and o-nitrobenzyl sulfonate compounds.

As the photoacid generator (B), a known compound that generates an acid by irradiation with active light or radiation can be appropriately selected and used alone or as a mixture thereof. For example, paragraphs [0125]-[0319] of U.S. Patent Application Publication 2016/0070167A1, paragraphs [0086]-[0094] of U.S. Patent Application Publication 2015/0004544A1, and U.S. Patent Application Publication 2016 / The known compounds disclosed in paragraphs [0323] to [0402] of 0237190A1 can be preferably used as the photoacid generator (B).

As the photoacid generator (B), for example, a compound represented by the following general formula (ZI), general formula (ZII), or general formula (ZIII) is preferable.

In the above general formula (ZI)
R ₂₀₁ , R ₂₀₂ and R ₂₀₃ each independently represent an organic group.
The number of carbon atoms of the organic group as R ₂₀₁ , R ₂₀₂ and R ₂₀₃ is generally 1 to 30, preferably 1 to 20.
Further, two of R ₂₀₁ to R ₂₀₃ may be bonded to form a ring structure, and the ring may contain an oxygen atom, a sulfur atom, an ester bond, an amide bond, or a carbonyl group. The two of the group formed by bonding of the R ₂₀₁ ~ _{R 203,} an alkylene group (e.g., butylene group, and pentylene group), and _{_{_{-CH 2 -CH 2 -O-CH 2}}} -CH 2 - is Can be mentioned.
Z ^- represents an anion.

Preferable embodiments of the cation in the general formula (ZI) include the corresponding groups in compound (ZI-1), compound (ZI-2), compound (ZI-3), and compound (ZI-4) described below. Be done.
The photoacid generator (B) may be a compound having a plurality of structures represented by the general formula (ZI). For example, at least one of _R 201 _{~ R 203} of the compound represented by formula (ZI), and at least one of _R 201 _{~ R 203} of another compound represented by formula (ZI), a single bond Alternatively, it may be a compound having a structure bonded via a linking group.

First, the compound (ZI-1) will be described.
The compound (ZI-1) is an aryl sulfonium compound in which at least one of R ₂₀₁ to R ₂₀₃ of the above general formula (ZI) is an aryl group, that is, a compound having aryl sulfonium as a cation.
In the aryl sulfonium compound, all of R ₂₀₁ to R ₂₀₃ may be an aryl group, or a part of R ₂₀₁ to R ₂₀₃ may be an aryl group and the rest may be an alkyl group or a cycloalkyl group.
Examples of the aryl sulfonium compound include a triaryl sulfonium compound, a diallyl alkyl sulfonium compound, an aryl dialkyl sulfonium compound, a diallyl cycloalkyl sulfonium compound, and an aryl dicycloalkyl sulfonium compound.

As the aryl group contained in the arylsulfonium compound, a phenyl group or a naphthyl group is preferable, and a phenyl group is more preferable. The aryl group may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the heterocyclic structure include pyrrole residues, furan residues, thiophene residues, indole residues, benzofuran residues, benzothiophene residues and the like. When the aryl sulfonium compound has two or more aryl groups, the two or more aryl groups may be the same or different.
The alkyl group or cycloalkyl group contained in the arylsulfonium compound as required is a linear alkyl group having 1 to 15 carbon atoms, a branched alkyl group having 3 to 15 carbon atoms, or a branched alkyl group having 3 to 15 carbon atoms. Cycloalkyl group is preferable, and examples thereof include methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group, t-butyl group, cyclopropyl group, cyclobutyl group, cyclohexyl group and the like.

The aryl group, alkyl group, and cycloalkyl group represented by R ₂₀₁ to R ₂₀₃ are independently an alkyl group (for example, 1 to 15 carbon atoms), a cycloalkyl group (for example, 3 to 15 carbon atoms), and an aryl group. It may have (for example, 6 to 14 carbon atoms), an alkoxy group (for example, 1 to 15 carbon atoms), a halogen atom, a hydroxyl group, or a phenylthio group as a substituent.

Next, the compound (ZI-2) will be described.
The compound (ZI-2) is a compound in which R ₂₀₁ to R ₂₀₃ in the formula (ZI) each independently represent an organic group having no aromatic ring. Here, the aromatic ring also includes an aromatic ring containing a hetero atom.
The organic group having no aromatic ring as R ₂₀₁ to R ₂₀₃ generally has 1 to 30 carbon atoms, and preferably 1 to 20 carbon atoms.
R ₂₀₁ to R ₂₀₃ are each independently preferably an alkyl group, a cycloalkyl group, an allyl group, or a vinyl group, and are linear or branched 2-oxoalkyl groups, 2-oxocycloalkyl groups, or alkoxy groups. A carbonyl methyl group is more preferred, and a linear or branched 2-oxoalkyl group is even more preferred.

Examples of the alkyl group and cycloalkyl group of R ₂₀₁ to R ₂₀₃ include a linear alkyl group having 1 to 10 carbon atoms or a branched chain alkyl group having 3 to 10 carbon atoms (for example, methyl group, ethyl group, propyl group, etc.). Butyl group and pentyl group) or cycloalkyl group having 3 to 10 carbon atoms (for example, cyclopentyl group, cyclohexyl group, and norbornyl group) are preferable.
R ₂₀₁ to R ₂₀₃ may be further substituted with a halogen atom, an alkoxy group (for example, 1 to 5 carbon atoms), a hydroxyl group, a cyano group, or a nitro group.

Next, the compound (ZI-3) will be described.
The compound (ZI-3) is represented by the following general formula (ZI-3) and has a phenacylsulfonium salt structure.

In the general formula (ZI-3),
R _1c to R _5c are independently hydrogen atom, alkyl group, cycloalkyl group, aryl group, alkoxy group, aryloxy group, alkoxycarbonyl group, alkylcarbonyloxy group, cycloalkylcarbonyloxy group, halogen atom, hydroxyl group. , Nitro group, alkylthio group or arylthio group.
R _6c and R _7c each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, a halogen atom, a cyano group or an aryl group.
R _x and R _y each independently represent an alkyl group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocycloalkyl group, an alkoxycarbonylalkyl group, an allyl group or a vinyl group.

Even if any two or more of R _1c to R _5c , R _5c and R _6c , R _6c and R _7c , R _5c and R _x , and R _x and R _y are combined to form a ring structure, respectively. Often, this ring structure may independently contain an oxygen atom, a sulfur atom, a ketone group, an ester bond, or an amide bond.
Examples of the ring structure include an aromatic or non-aromatic hydrocarbon ring, an aromatic or non-aromatic heterocycle, and a polycyclic fused ring formed by combining two or more of these rings. Examples of the ring structure include a 3- to 10-membered ring, preferably a 4- to 8-membered ring, and more preferably a 5- or 6-membered ring.

_{Examples of} the group formed by combining any two or more of R _1c to R _5c , R _6c and R _7c , and R _x and R _y include a butylene group and a pentylene group.
As the group formed by bonding R _5c and R _6c , and R _5c and R _x , a single bond or an alkylene group is preferable. Examples of the alkylene group include a methylene group and an ethylene group.
Zc ^- represents an anion.

Next, the compound (ZI-4) will be described.
The compound (ZI-4) is represented by the following general formula (ZI-4).

In the general formula (ZI-4),
l represents an integer of 0 to 2.
r represents an integer from 0 to 8.
R ₁₃ represents a group having a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, or a cycloalkyl group. These groups may have substituents.
R ₁₄ represents a hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkylcarbonyl group, an alkylsulfonyl group, a cycloalkylsulfonyl group, or a group having a cycloalkyl group. These groups may have substituents. When a plurality of R ₁₄ are present, each independently represents the above group such as a hydroxyl group.
R ₁₅ independently represents an alkyl group, a cycloalkyl group, or a naphthyl group. These groups may have substituents. Bonded to two R ₁₅ each other may form a ring. When two R ₁₅ are combined to form a ring together, in the ring skeleton may contain a hetero atom such as an oxygen atom, or a nitrogen atom. In one embodiment, two R ₁₅ is an alkylene group, it is preferable to form a ring structure.
Z ^- represents an anion.

In the general formula (ZI-4), the alkyl groups represented by R ₁₃ , R ₁₄ and R ₁₅ are linear or branched chain. The alkyl group preferably has 1 to 10 carbon atoms. As the alkyl group, a methyl group, an ethyl group, an n-butyl group, or a t-butyl group is preferable.

Next, the general formulas (ZII) and (ZIII) will be described.
In the general formulas (ZII) and (ZIII), R ₂₀₄ to R ₂₀₇ each independently represent an aryl group, an alkyl group or a cycloalkyl group.
As the aryl group represented by R ₂₀₄ to R ₂₀₇ , a phenyl group or a naphthyl group is preferable, and a phenyl group is more preferable. The aryl group represented by R ₂₀₄ to R ₂₀₇ may be an aryl group having a heterocyclic structure having an oxygen atom, a nitrogen atom, a sulfur atom or the like. Examples of the skeleton of the aryl group having a heterocyclic structure include pyrrole, furan, thiophene, indole, benzofuran, and benzothiophene.
Examples of the alkyl group and cycloalkyl group represented by R ₂₀₄ to R ₂₀₇ include a linear alkyl group having 1 to 10 carbon atoms and a branched chain alkyl group having 3 to 10 carbon atoms (for example, a methyl group and an ethyl group). A propyl group, a butyl group, a pentyl group, etc.) or a cycloalkyl group having 3 to 10 carbon atoms (for example, a cyclopentyl group, a cyclohexyl group, a norbornyl group, etc.) is preferable.

The aryl group, alkyl group, and cycloalkyl group represented by R ₂₀₄ to R ₂₀₇ may each independently have a substituent. Examples of the substituent which the aryl group represented by R ₂₀₄ to R ₂₀₇ , the alkyl group, and the cycloalkyl group may have include an alkyl group (for example, 1 to 15 carbon atoms) and a cycloalkyl group (for example, carbon). Numbers 3 to 15), aryl groups (for example, 6 to 15 carbon atoms), alkoxy groups (for example, 1 to 15 carbon atoms), halogen atoms, hydroxyl groups, phenylthio groups and the like.
Z ^- represents an anion.

Z in the general formula (ZI) ^-, Z in the general formula (ZII) ^-, Zc in formula (ZI-3) ^-, and Z in the general formula (ZI-4) ^- as the following general formula (3) The represented anion is preferred.

In general formula (3),
o represents an integer of 1 to 3. p represents an integer from 0 to 10. q represents an integer from 0 to 10.

Xf represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. The number of carbon atoms of this alkyl group is preferably 1 to 10, and more preferably 1 to 4. Further, as the alkyl group substituted with at least one fluorine atom, a perfluoroalkyl group is preferable.
Xf is preferably a fluorine atom or a perfluoroalkyl group having 1 to 4 carbon atoms, and more preferably a fluorine atom or CF ₃ . In particular, it is more preferable that both Xfs are fluorine atoms.

R ₄ and R ₅ each independently represent a hydrogen atom, a fluorine atom, an alkyl group, or an alkyl group substituted with at least one fluorine atom. If R ₄ and _{R 5} there are a plurality, _{R 4} and _{R 5} may each be the same or different.
The alkyl group represented by R ₄ and R ₅ may have a substituent, and has 1 to 4 carbon atoms. R ₄ and R ₅ are preferably hydrogen atoms.
Specific examples and preferred embodiments of the alkyl group substituted with at least one fluorine atom are the same as the specific examples and preferred embodiments of Xf in the general formula (3).

L represents a divalent linking group. When there are a plurality of L's, the L's may be the same or different.
The divalent linking group includes, for example, -COO- (-C (= O) -O-), -OCO-, -CONH-, -NHCO-, -CO-, -O-, -S-,-. SO-, -SO _2- , alkylene group (preferably 1 to 6 carbon atoms), cycloalkylene group (preferably 3 to 15 carbon atoms), alkenylene group (preferably 2 to 6 carbon atoms), and a plurality of these. Examples thereof include a combined divalent linking group. Among them, -COO -, - OCO -, - CONH -, - NHCO -, - CO -, - O -, - SO 2 -, - COO- alkylene group -, - OCO- alkylene group -, - CONH- alkylene group -, or -NHCO- alkylene group - are preferred, -COO -, - OCO -, - CONH -, - SO 2 -, - COO- alkylene group -, or -OCO- alkylene group - is more preferable.

W represents an organic group containing a cyclic structure. Among these, a cyclic organic group is preferable.
Examples of the cyclic organic group include an alicyclic group, an aryl group, and a heterocyclic group.
The alicyclic group may be a monocyclic type or a polycyclic type. Examples of the monocyclic alicyclic group include a monocyclic cycloalkyl group such as a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include a polycyclic cycloalkyl group such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group. Of these, alicyclic groups having a bulky structure having 7 or more carbon atoms, such as a norbornyl group, a tricyclodecanyl group, a tetracyclodecanyl group, a tetracyclododecanyl group, and an adamantyl group, are preferable.

The aryl group may be monocyclic or polycyclic. Examples of the aryl group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group.
The heterocyclic group may be monocyclic or polycyclic. The polycyclic type can suppress the diffusion of acid more. Further, the heterocyclic group may or may not have aromaticity. Examples of the aromatic heterocycle include a furan ring, a thiophene ring, a benzofuran ring, a benzothiophene ring, a dibenzofuran ring, a dibenzothiophene ring, and a pyridine ring. Examples of the non-aromatic heterocycle include a tetrahydropyran ring, a lactone ring, a sultone ring, and a decahydroisoquinoline ring. Examples of the lactone ring and the sultone ring include the lactone structure and the sultone structure exemplified in the above-mentioned resin. As the heterocycle in the heterocyclic group, a furan ring, a thiophene ring, a pyridine ring, or a decahydroisoquinoline ring is particularly preferable.

The cyclic organic group may have a substituent. Examples of the substituent include an alkyl group (which may be linear or branched, preferably having 1 to 12 carbon atoms) and a cycloalkyl group (monocyclic, polycyclic, and spiroring). Any of them may be used, preferably 3 to 20 carbon atoms), an aryl group (preferably 6 to 14 carbon atoms), a hydroxyl group, an alkoxy group, an ester group, an amide group, a urethane group, a ureido group, a thioether group and a sulfonamide. Examples include groups and sulfonic acid ester groups. The carbon constituting the cyclic organic group (carbon that contributes to ring formation) may be carbonyl carbon.

Formula (3) As the anion represented _{^{_{_{by, SO 3 - -CF 2 -CH 2}}}} -OCO- (L) q'-W, SO 3 - -CF 2 -CHF-CH 2 -OCO- (L) _{^{_{q'-W, SO 3 - -CF}}} 2 -COO- (L) q'-W, SO 3 - -CF 2 -CF 2 -CH 2 -CH 2 - (L) q-W, or, SO ₃ ^- -CF _2- CH (CF ₃ ) -OCO- (L) q'-W is preferable. Here, L, q and W are the same as in the general formula (3). q'represents an integer from 0 to 10.

In one embodiment, Z in formula (ZI) ^-, Z in the general formula (ZII) ^-, Zc in formula (ZI-3) ^-, and Z in the general formula (ZI-4) ^- as is generally the following An anion represented by the formula (4) is also preferable.

In general formula (4),
X ^B1 and X ^B2 each independently represent a monovalent organic group having no hydrogen atom or fluorine atom. It is preferable that X ^B1 and X ^B2 are hydrogen atoms.
X ^B3 and X ^B4 each independently represent a hydrogen atom or a monovalent organic group. It is preferable that at least one of X ^B3 and X ^B4 is a fluorine atom or a monovalent organic group having a fluorine atom, and both X ^B3 and X ^B4 are monovalent organic groups having a fluorine atom or a fluorine atom. Is more preferable. It is even more preferred that both X ^B3 and X ^B4 are fluorine-substituted alkyl groups.
L, q and W are the same as those in the general formula (3).

Z in the general formula (ZI) ^-, Z in the general formula (ZII) ^-, Zc in formula (ZI-3) ^-, and Z in the general formula (ZI-4) ^- as the following general formula (5) The represented anion is preferred.

In the general formula (5), Xa independently represents a fluorine atom or an alkyl group substituted with at least one fluorine atom. Xb independently represents an organic group having no hydrogen atom or fluorine atom. The definitions and preferred embodiments of o, p, q, R ₄ , R ₅ , L, and W are the same as in the general formula (3).

Z in the general formula (ZI) ^-, Z in the general formula (ZII) ^-, Zc in formula (ZI-3) ^-, and Z in the general formula (ZI-4) ^- may be a benzenesulfonic acid anion Often, it is preferably a benzenesulfonic acid anion substituted with a branched chain alkyl group or a cycloalkyl group.

Z in the general formula (ZI) ^-, the formula Z in (ZII) ^-, Zc in formula (ZI-3) ^- Z in, and the general formula (ZI-4) ^- The following general formula (SA1) Aromatic sulfonic acid anions represented by are also preferable.

In formula (SA1),
Ar represents an aryl group and may further have a substituent other than the sulfonic acid anion and the- (DB) group. Further, examples of the substituent which may be possessed include a fluorine atom and a hydroxyl group.

N represents an integer of 0 or more. As n, 1 to 4 is preferable, 2 to 3 is more preferable, and 3 is further preferable.

D represents a single bond or a divalent linking group. Examples of the divalent linking group include an ether group, a thioether group, a carbonyl group, a sulfoxide group, a sulfone group, a sulfonic acid ester group, an ester group, and a group composed of a combination of two or more of these.

B represents a hydrocarbon group.

It is preferable that D is a single bond and B is an aliphatic hydrocarbon structure. B is more preferably an isopropyl group or a cyclohexyl group.

Preferred examples of the sulfonium cation in the general formula (ZI) and the iodonium cation in the general formula (ZII) are shown below.

Generally the anion Z in formula (ZI) ^-, the anion in the general formula (ZII) Z ^-, Zc in formula (ZI-3) ^-, and the general formula Z in (ZI-4) ^- shows the preferred embodiment below.

The above cations and anions can be arbitrarily combined and used as a photoacid generator (B).

The photoacid generator (B) may be in the form of a low molecular weight compound or may be incorporated in a part of the polymer. Further, the form of the low molecular weight compound and the form incorporated in a part of the polymer may be used in combination.
The photoacid generator (B) is preferably in the form of a low molecular weight compound.
When the photoacid generator (B) is in the form of a low molecular weight compound, the molecular weight is preferably 3,000 or less, more preferably 2,000 or less, still more preferably 1,000 or less.
When the photoacid generator (B) is incorporated in a part of the polymer, it may be incorporated in a part of the resin (A) described above, and is incorporated in a resin different from the resin (A). You may.
The photoacid generator (B) may be used alone or in combination of two or more.
The content of the photoacid generator (B) in the resist composition (if a plurality of types are present, the total thereof) is preferably 0.1 to 35.0% by mass, preferably 0, based on the total solid content of the composition. .5 to 25.0% by mass is more preferable, and 3.0 to 20.0% by mass is further preferable.
When the photoacid generator contains a compound represented by the above general formula (ZI-3) or (ZI-4), the content of the photoacid generator contained in the resist composition (when a plurality of types are present). The total) is preferably 5 to 35% by mass, more preferably 7 to 30% by mass, based on the total solid content of the composition.

The acid dissociation constant pKa of the acid generated by decomposition of the photoacid generator (B) by irradiation with active light or radiation is, for example, −0.01 or less, preferably −1.00 or less. It is more preferably −1.50 or less, and further preferably −2.00 or less. The lower limit of pKa is not particularly limited, but is, for example, −5.00 or higher. pKa can be measured by the method described above.

<Acid diffusion control agent (C)>
The resist composition preferably contains an acid diffusion control agent as long as it does not interfere with the effects of the present invention.
The acid diffusion control agent (C) acts as a citric acid that traps the acid generated from the acid generator or the like during exposure and suppresses the reaction of the acid-degradable resin in the unexposed portion due to the excess generated acid. .. Examples of the acid diffusion control agent (C) include a basic compound (CA), a basic compound (CB) whose basicity is reduced or eliminated by irradiation with active light or radiation, and a weak acid relative to an acid generator. Acid diffusion control of onium salt (CC), low molecular weight compound (CD) having a nitrogen atom and a group desorbed by the action of acid, or onium salt compound (CE) having a nitrogen atom in the cation part, etc. Can be used as an agent. In the resist composition, a known acid diffusion control agent can be appropriately used. For example, paragraphs [0627] to [0664] of U.S. Patent Application Publication No. 2016/0070167A1, paragraphs [0995] to [0187] of U.S. Patent Application Publication No. 2015/0004544A1, U.S. Patent Application Publication No. 2016/0237190A1. Known compounds disclosed in paragraphs [0403] to [0423] of the specification and paragraphs [0259] to [0328] of US Patent Application Publication No. 2016/0274458A1 are suitable as the acid diffusion control agent (C). Can be used for.

As the basic compound (CA), compounds having a structure represented by the following formulas (A) to (E) are preferable.

In the general formulas (A) and (E),
R ²⁰⁰ , R ²⁰¹ and R ²⁰² may be the same or different, and each independently has a hydrogen atom, an alkyl group (preferably 1 to 20 carbon atoms), a cycloalkyl group (preferably 3 to 20 carbon atoms) or an aryl. Represents a group (6 to 20 carbon atoms). R ²⁰¹ and R ²⁰² may be combined with each other to form a ring.
R ²⁰³ , R ²⁰⁴ , R ²⁰⁵ and R ²⁰⁶ may be the same or different, and each independently represents an alkyl group having 1 to 20 carbon atoms.

The alkyl groups in the general formulas (A) and (E) may have a substituent or may be unsubstituted.
Regarding the above alkyl group, as the alkyl group having a substituent, an aminoalkyl group having 1 to 20 carbon atoms, a hydroxyalkyl group having 1 to 20 carbon atoms, or a cyanoalkyl group having 1 to 20 carbon atoms is preferable.
It is more preferable that the alkyl groups in the general formulas (A) and (E) are unsubstituted.

As the basic compound (CA), guanidine, aminopyrrolidin, pyrazole, pyrazoline, piperazine, aminomorpholin, aminoalkylmorpholin, piperidine and the like are preferable, and imidazole structure, diazabicyclo structure, onium hydroxide structure, onium carboxylate structure, etc. A compound having a trialkylamine structure, an aniline structure or a pyridine structure, an alkylamine derivative having a hydroxyl group and / or an ether bond, an aniline derivative having a hydroxyl group and / or an ether bond, and the like are more preferable.

A basic compound (CB) whose basicity is reduced or eliminated by irradiation with active light or radiation (hereinafter, also referred to as “compound (CB)”) has a proton acceptor functional group and is active light or It is a compound that is decomposed by irradiation with radiation to reduce or disappear its proton accepting property, or to change from proton accepting property to acidic.

A proton-accepting functional group is a functional group having a group or an electron capable of electrostatically interacting with a proton, for example, a functional group having a macrocyclic structure such as a cyclic polyether, or a π-conjugated group. It means a functional group having a nitrogen atom having an unshared electron pair that does not contribute to. The nitrogen atom having an unshared electron pair that does not contribute to π conjugation is, for example, a nitrogen atom having a partial structure shown in the following formula.

Preferred partial structures of the proton acceptor functional group include, for example, a crown ether structure, an aza crown ether structure, a primary to tertiary amine structure, a pyridine structure, an imidazole structure, a pyrazine structure and the like.

The compound (CB) is decomposed by irradiation with active light or radiation to reduce or eliminate the proton acceptor property, or generate a compound in which the proton acceptor property is changed to acidic. Here, the decrease or disappearance of the proton acceptor property, or the change from the proton acceptor property to the acidity is a change in the proton acceptor property due to the addition of a proton to the proton acceptor property functional group, and is specific. Means that when a proton adduct is formed from a compound (CB) having a proton-accepting functional group and a proton, the equilibrium constant in its chemical equilibrium decreases.
Proton acceptability can be confirmed by measuring pH.

The acid dissociation constant pKa of the compound generated by decomposition of the compound (CB) by irradiation with active light or radiation preferably satisfies pKa <-1, more preferably -13 <pKa <-1, and-. It is more preferable to satisfy 13 <pKa <-3.

The acid dissociation constant pKa can be obtained by the method described above.

In the resist composition, an onium salt (CC), which is a weak acid relative to the acid generator, can be used as the acid diffusion control agent.
When an acid generator and an onium salt that generates an acid that is a weak acid relative to the acid generated from the acid generator are mixed and used, the acid generator is generated by active light or irradiation with radiation. When the acid collides with an onium salt having an unreacted weak acid anion, salt exchange releases the weak acid to produce an onium salt with a strong acid anion. In this process, the strong acid is exchanged for the weak acid having a lower catalytic ability, so that the acid is apparently inactivated and the acid diffusion can be controlled.

As the onium salt that is relatively weak acid with respect to the acid generator, compounds represented by the following general formulas (d1-1) to (d1-3) are preferable.

In the formula, R ⁵¹ is a hydrocarbon group which may have a substituent, and Z ^2c is a hydrocarbon group having 1 to 30 carbon atoms which may have a substituent (however, carbon adjacent to S). R ⁵² is an organic group, Y ³ is a linear, branched or cyclic alkylene group or arylene group, and Rf is a fluorine atom. It is a hydrocarbon group containing, and M ⁺ is independently an ammonium cation, a sulfonium cation, or an iodonium cation.

Preferred examples of the sulfonium cation or iodonium cation represented by M ⁺ include the sulfonium cation exemplified by the general formula (ZI) and the iodonium cation exemplified by the general formula (ZII).

An onium salt (CC), which is a relatively weak acid with respect to an acid generator, is a compound having a cation moiety and an anion moiety in the same molecule, and the cation moiety and anion moiety are linked by a covalent bond ( Hereinafter, it may also be referred to as “compound (CCA)”).
The compound (CCA) is preferably a compound represented by any of the following general formulas (C-1) to (C-3).

In the general formulas (C-1) to (C-3),
R ₁ , R ₂ , and R ₃ each independently represent a substituent having 1 or more carbon atoms.
L ₁ represents a divalent linking group or a single bond that links the cation site and the anion site.
-X ^- ^_is, -COO ^-, ^-SO 3 - represents an anion portion selected from -R ₄ ^-, -SO ₂ -, and ^-N. R ₄ is a linking site with the adjacent N atom, a carbonyl group (-C (= O) -) , sulfonyl group _{(-S (= O) 2 -} ), and sulfinyl group (-S (= O) - ) Represents a monovalent substituent having at least one of them.
R ₁ , R ₂ , R ₃ , R ₄ , and L ₁ may be combined with each other to form a ring structure. Further, in the general formula (C-3), two of R ₁ to R ₃ are combined to represent one divalent substituent, which may be bonded to an N atom by a double bond.

Substituents having 1 or more carbon atoms in R ₁ to R ₃ include an alkyl group, a cycloalkyl group, an aryl group, an alkyloxycarbonyl group, a cycloalkyloxycarbonyl group, an aryloxycarbonyl group, an alkylaminocarbonyl group and a cycloalkylamino. Examples thereof include a carbonyl group and an arylaminocarbonyl group. Of these, an alkyl group, a cycloalkyl group, or an aryl group is preferable.

L ₁ as a divalent linking group includes a linear or branched alkylene group, a cycloalkylene group, an arylene group, a carbonyl group, an ether bond, an ester bond, an amide bond, a urethane bond, a urea bond, and two kinds thereof. Examples thereof include groups formed by combining the above. L ₁ is preferably an alkylene group, an arylene group, an ether bond, an ester bond, or a group formed by combining two or more of these.

A low molecular weight compound (CD) having a nitrogen atom and having a group desorbed by the action of an acid (hereinafter, also referred to as “compound (CD)”) has a group desorbed by the action of an acid on the nitrogen atom. It is preferably an amine derivative having.
As the group desorbed by the action of the acid, an acetal group, a carbonate group, a carbamate group, a tertiary ester group, a tertiary hydroxyl group, or a hemiaminol ether group is preferable, and a carbamate group or a hemiaminol ether group is more preferable. ..
The molecular weight of the compound (CD) is preferably 100 to 1000, more preferably 100 to 700, and even more preferably 100 to 500.
Compound (CD) may have a carbamate group having a protecting group on the nitrogen atom. The protecting group constituting the carbamate group is represented by the following general formula (d-1).

In the general formula (d-1)
Rb is independently a hydrogen atom, an alkyl group (preferably 1 to 10 carbon atoms), a cycloalkyl group (preferably 3 to 30 carbon atoms), an aryl group (preferably 3 to 30 carbon atoms), and an aralkyl group (preferably 3 to 30 carbon atoms). It preferably represents 1 to 10 carbon atoms) or an alkoxyalkyl group (preferably 1 to 10 carbon atoms). Rb may be connected to each other to form a ring.
The alkyl group, cycloalkyl group, aryl group, and aralkyl group represented by Rb are independently hydroxyl groups, cyano groups, amino groups, pyrrolidino groups, piperidino groups, morpholino groups, oxo groups and other functional groups, alkoxy groups, or halogens. It may be replaced with an atom. The same applies to the alkoxyalkyl group indicated by Rb.

As Rb, a linear or branched alkyl group, a cycloalkyl group, or an aryl group is preferable, and a linear or branched alkyl group or a cycloalkyl group is more preferable.
Examples of the ring formed by connecting the two Rbs to each other include an alicyclic hydrocarbon, an aromatic hydrocarbon, a heterocyclic hydrocarbon, and a derivative thereof.
Specific structures of the group represented by the general formula (d-1) include, but are not limited to, the structure disclosed in paragraph [0466] of US Patent Publication US2012 / 0135348A1.

The compound (CD) preferably has a structure represented by the following general formula (6).

In the general formula (6)
l represents an integer of 0 to 2, m represents an integer of 1 to 3, and satisfies l + m = 3.
Ra represents a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group or an aralkyl group. When l is 2, the two Ras may be the same or different, and the two Ras may be interconnected to form a heterocycle with the nitrogen atom in the equation. This heterocycle may contain a heteroatom other than the nitrogen atom in the formula.
Rb has the same meaning as Rb in the above general formula (d-1), and the same applies to preferred examples.
In the general formula (6), the alkyl group, cycloalkyl group, aryl group, and aralkyl group as Ra are independently substituted with the alkyl group, cycloalkyl group, aryl group, and aralkyl group as Rb, respectively. As a good group, it may be substituted with a group similar to the group described above.

Specific examples of the alkyl group, cycloalkyl group, aryl group, and aralkyl group of Ra (these groups may be substituted with the above group) include groups similar to the above-mentioned specific examples for Rb. Be done.
Specific examples of particularly preferred compounds (CDs) in the present invention include, but are not limited to, the compounds disclosed in paragraph [0475] of U.S. Patent Application Publication 2012 / 0135348A1.

The onium salt compound (CE) having a nitrogen atom in the cation portion (hereinafter, also referred to as “compound (CE)”) is preferably a compound having a basic moiety containing a nitrogen atom in the cation portion. The basic moiety is preferably an amino group, more preferably an aliphatic amino group. It is more preferable that all the atoms adjacent to the nitrogen atom in the basic moiety are hydrogen atoms or carbon atoms. Further, from the viewpoint of improving basicity, it is preferable that an electron-attracting functional group (carbonyl group, sulfonyl group, cyano group, halogen atom, etc.) is not directly bonded to the nitrogen atom.
Preferred specific examples of the compound (CE) include, but are not limited to, the compound disclosed in paragraph [0203] of US Patent Application Publication 2015/0309408A1.

A preferable example of the acid diffusion control agent (C) is shown below.

In the resist composition, the acid diffusion control agent (C) may be used alone or in combination of two or more.
When the acid diffusion control agent (C) is contained in the resist composition, the content of the acid diffusion control agent (C) (if a plurality of types are present, the total thereof) is determined to be 0, based on the total solid content of the composition. It is preferably 01 to 10.0% by mass, more preferably 0.01 to 5.0% by mass.

<Hydrophobic resin (D)>
The resist composition may contain a hydrophobic resin (D). The hydrophobic resin (D) is preferably a resin different from the resin (A).
By including the hydrophobic resin (D) in the resist composition, the static / dynamic contact angle on the surface of the sensitive light-sensitive or radiation-sensitive film can be controlled. This makes it possible to improve development characteristics, suppress outgas, improve immersion liquid followability in immersion exposure, reduce immersion defects, and the like.
The hydrophobic resin (D) is preferably designed to be unevenly distributed on the surface of the resist film, but unlike a surfactant, it does not necessarily have to have a hydrophilic group in the molecule, and a polar / non-polar substance is used. It does not have to contribute to uniform mixing.

Hydrophobic resin (D), from the viewpoint of uneven distribution in the film surface layer, "fluorine atom", "silicon atom", and is selected from the group consisting of "CH ₃ partial structure contained in the side chain portion of the resin" It is preferable that the resin has a repeating unit having at least one kind.
When the hydrophobic resin (D) contains a fluorine atom and / or a silicon atom, the fluorine atom and / or the silicon atom in the hydrophobic resin (D) may be contained in the main chain of the resin, and the side It may be contained in the chain.

When the hydrophobic resin (D) contains a fluorine atom, the partial structure having a fluorine atom may be a resin having an alkyl group having a fluorine atom, a cycloalkyl group having a fluorine atom, or an aryl group having a fluorine atom. preferable.

The hydrophobic resin (D) preferably has at least one group selected from the following groups (x) to (z).
(X) Acid group (y) A group that decomposes by the action of an alkaline developer and increases its solubility in an alkaline developer (hereinafter, also referred to as a polarity converting group).
(Z) Group decomposed by the action of acid

Examples of the acid group (x) include a phenolic hydroxyl group, a carboxylic acid group, a fluorinated alcohol group, a sulfonic acid group, a sulfonyl group, a sulfonylimide group, a (alkylsulfonyl) (alkylcarbonyl) methylene group, and (alkylsulfonyl) (alkyl). Carbonyl) imide group, bis (alkylcarbonyl) methylene group, bis (alkylcarbonyl) imide group, bis (alkylsulfonyl) methylene group, bis (alkylsulfonyl) imide group, tris (alkylcarbonyl) methylene group, and tris (alkylsulfonyl) ) Methylene groups and the like can be mentioned.
As the acid group, a fluorinated alcohol group (preferably hexafluoroisopropanol), a sulfonimide group, or a bis (alkylcarbonyl) methylene group is preferable.

Examples of the group (y) that decomposes due to the action of the alkaline developing solution and increases the solubility in the alkaline developing solution include a lactone group, a carboxylic acid ester group (-COO-), and an acid anhydride group (-C (O) OC). (O)-), acidimide group (-NHCONH-), carboxylic acid thioester group (-COS-), carbonate ester group (-OC (O) O-), sulfate ester group (-OSO ₂ O-), and Examples thereof include a sulfonic acid ester group (-SO ₂ O-), and a lactone group or a carboxylic acid ester group (-COO-) is preferable.
The repeating unit containing these groups is, for example, a repeating unit in which these groups are directly bonded to the main chain of a resin, and examples thereof include a repeating unit made of an acrylic acid ester and a methacrylic acid ester. In this repeating unit, these groups may be bonded to the main chain of the resin via a linking group. Alternatively, the repeating unit may be introduced into the end of the resin by using a polymerization initiator or chain transfer agent having these groups at the time of polymerization.
Examples of the repeating unit having a lactone group include the same repeating units having the lactone structure described above in the section of resin (A).

The content of the repeating unit having a group (y) that decomposes by the action of the alkaline developer and increases the solubility in the alkaline developer is 1 to 100 mol% with respect to all the repeating units in the hydrophobic resin (D). Is preferable, 3 to 98 mol% is more preferable, and 5 to 95 mol% is further preferable.

In the hydrophobic resin (D), the repeating unit having a group (z) that decomposes by the action of an acid may be the same as the repeating unit having an acid-degradable group mentioned in the resin (A). The repeating unit having a group (z) decomposed by the action of an acid may have at least one of a fluorine atom and a silicon atom. The content of the repeating unit having the group (z) decomposed by the action of the acid is preferably 1 to 80 mol%, more preferably 10 to 80 mol%, based on all the repeating units in the hydrophobic resin (D). , 20-60 mol% is more preferred.
The hydrophobic resin (D) may further have a repeating unit different from the repeating unit described above.

The repeating unit having a fluorine atom is preferably 10 to 100 mol%, more preferably 30 to 100 mol%, based on all the repeating units in the hydrophobic resin (D). The repeating unit having a silicon atom is preferably 10 to 100 mol%, more preferably 20 to 100 mol%, based on all the repeating units in the hydrophobic resin (D).

On the other hand, especially in case of containing a CH ₃ partial structure in the hydrophobic resin (D) is a side chain moiety, a hydrophobic resin (D) is also preferable that is substantially free of fluorine atom and a silicon atom. Further, it is preferable that the hydrophobic resin (D) is substantially composed of only repeating units composed of only atoms selected from carbon atoms, oxygen atoms, hydrogen atoms, nitrogen atoms and sulfur atoms.

The weight average molecular weight of the hydrophobic resin (D) in terms of standard polystyrene is preferably 1,000 to 100,000, more preferably 1,000 to 50,000.

The total content of the residual monomer and / or oligomer component contained in the hydrophobic resin (D) is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass. The degree of dispersion (Mw / Mn) is preferably in the range of 1 to 5, and more preferably in the range of 1 to 3.

As the hydrophobic resin (D), a known resin can be appropriately selected and used alone or as a mixture thereof. For example, known resins disclosed in paragraphs [0451]-[0704] of U.S. Patent Application Publication 2015 / 0168830A1 and paragraphs [0340]-[0356] of U.S. Patent Application Publication 2016 / 0274458A1. Can be suitably used as the hydrophobic resin (D). Further, the repeating unit disclosed in paragraphs [0177] to [0258] of US Patent Application Publication No. 2016/0237190A1 is also preferable as the repeating unit constituting the hydrophobic resin (D).

A preferable example of the monomer corresponding to the repeating unit constituting the hydrophobic resin (D) is shown below.

The hydrophobic resin (D) may be used alone or in combination of two or more.
It is preferable to mix and use two or more kinds of hydrophobic resins (D) having different surface energies from the viewpoint of achieving both immersion liquid followability and development characteristics in immersion exposure.
The content of the hydrophobic resin (D) in the resist composition is preferably 0.01 to 20.0% by mass, more preferably 0.05 to 8.0% by mass, based on the total solid content in the composition. ..

<Solvent (E)>
The resist composition contains a solvent.
The solvent contained in the resist composition may include not only the solvent brought in by the polymer solution but also the solvent separately added in the step B.
In the resist composition, a known resist solvent can be appropriately used. For example, paragraphs [0665] to [0670] of U.S. Patent Application Publication No. 2016/0070167A1, paragraphs [0210] to [0235] of U.S. Patent Application Publication No. 2015/0004544A1, U.S. Patent Application Publication No. 2016/0237190A1. Known solvents disclosed in paragraphs [0424] to [0426] of the specification and paragraphs [0357] to [0366] of US Patent Application Publication No. 2016/0274458A1 can be preferably used.
Examples of the solvent that can be used when preparing the resist composition include alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, lactic acid alkyl ester, alkyl alkoxypropionate, and cyclic lactone (preferably having 4 to 10 carbon atoms). , Monoketone compounds which may have a ring (preferably 4 to 10 carbon atoms), organic solvents such as alkylene carbonate, alkyl alkoxyacetate, and alkyl pyruvate.

As the organic solvent, a mixed solvent in which a solvent having a hydroxyl group in the structure and a solvent having no hydroxyl group may be used may be used.
As the solvent having a hydroxyl group and the solvent having no hydroxyl group, the above-mentioned exemplified compounds can be appropriately selected, but as the solvent containing a hydroxyl group, alkylene glycol monoalkyl ether, alkyl lactate and the like are preferable, and propylene glycol monomethyl ether (propylene glycol monomethyl ether). PGME), propylene glycol monoethyl ether (PGEE), methyl 2-hydroxyisobutyrate, or ethyl lactate is more preferred. Further, as the solvent having no hydroxyl group, alkylene glycol monoalkyl ether acetate, alkylalkoxypropionate, monoketone compound which may have a ring, cyclic lactone, alkyl acetate and the like are preferable, and among these, propylene Glycol monomethyl ether acetate (PGMEA), ethyl ethoxypropionate, 2-heptanone, γ-butyrolactone, cyclohexanone, cyclopentanone or butyl acetate are more preferred, propylene glycol monomethyl ether acetate, γ-butyrolactone, ethyl ethoxypropionate, Cyclohexanone, cyclopentanone or 2-heptanone is more preferred. Propylene carbonate is also preferable as the solvent having no hydroxyl group.
The mixing ratio (mass ratio) of the solvent having a hydroxyl group and the solvent having no hydroxyl group is 1/99 to 99/1, preferably 10/90 to 90/10, more preferably 20/80 to 60/40. preferable. A mixed solvent containing 50% by mass or more of a solvent having no hydroxyl group is preferable in terms of coating uniformity.
The solvent preferably contains propylene glycol monomethyl ether acetate, and may be a propylene glycol monomethyl ether acetate single solvent or a mixed solvent of two or more kinds containing propylene glycol monomethyl ether acetate.

<Surfactant (F)>
The resist composition may contain a surfactant. When a surfactant is contained, a fluorine-based and / or a silicon-based surfactant (specifically, a fluorine-based surfactant, a silicon-based surfactant, or a surfactant having both a fluorine atom and a silicon atom) Is preferable.

When the resist composition contains a surfactant, a pattern having good sensitivity and resolution and few adhesions and development defects can be obtained when an exposure light source of 250 nm or less, particularly 220 nm or less is used.
Fluorine-based and / or silicon-based surfactants include those described in paragraph [0276] of US Patent Application Publication No. 2008/0248425.
In addition, other surfactants other than the fluorine-based and / or silicon-based surfactants described in paragraph [0280] of US Patent Application Publication No. 2008/0248425 can also be used.

These surfactants may be used alone or in combination of two or more.
When the resist composition contains a surfactant, the content of the surfactant is, for example, 0.0001 to 20% by mass and 0.0001 to 2.0% by mass with respect to the total solid content of the composition. Is preferable, and 0.0005 to 1.0% by mass is more preferable.
On the other hand, when the content of the surfactant is 10 ppm or more with respect to the total solid content of the composition, the uneven distribution of the surface of the hydrophobic resin (D) is increased. As a result, the surface of the resist film formed from the resist composition can be made more hydrophobic, and the water followability during immersion exposure is improved.

<Other additives>
The resist composition may further contain other additives such as acid growth agents, dyes, plasticizers, photosensitizers, light absorbers, alkali-soluble resins, dissolution inhibitors, and dissolution accelerators. ..

<Preparation method>
When the light source wavelength used in the exposure step is other than KrF rays, the solid content concentration of the resist composition is usually preferably 1.0 to 10% by mass, more preferably 2.0 to 5.7% by mass. It is more preferably 0 to 5.3% by mass. When the light source wavelength used in the exposure step is KrF line, it is usually preferably 1.0 to 50% by mass, more preferably 2.0 to 30% by mass. The solid content concentration is the mass percentage of the mass of other resist components excluding the solvent with respect to the total mass of the composition.

From the viewpoint of improving the resolving power, the film thickness of the resist film formed from the resist composition is preferably 90 nm or less, more preferably 85 nm or less, and more preferably 85 nm or less, when the light source wavelength used in the exposure step is other than KrF line. When the light source wavelength used for is KrF line, it is preferably 1000 nm or less, more preferably 800 nm or less. Such a film thickness can be obtained by setting the solid content concentration in the resist composition in an appropriate range to give an appropriate viscosity and improving the coatability or the film forming property.

The resist composition is used by dissolving the above components in a predetermined organic solvent, preferably the mixed solvent, filtering the mixture, and then applying the resist composition onto a predetermined support (substrate). The pore size of the filter used for filter filtration is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.03 μm or less. When the solid content concentration of the resist composition is high (for example, 25% by mass or more), the pore size of the filter used for filter filtration is preferably 3 μm or less, more preferably 0.5 μm or less, still more preferably 0.3 μm or less. .. The filter is preferably made of polytetrafluoroethylene, polyethylene, or nylon. In filter filtration, for example, as disclosed in Japanese Patent Application Publication No. 2002-62667 (Japanese Patent Laid-Open No. 2002-62667), cyclic filtration may be performed, and a plurality of types of filters may be arranged in series or in parallel. It may be connected to and filtered. Moreover, you may filter the resist composition a plurality of times. Further, the resist composition may be degassed before and after the filter filtration.

[Use]
The resist composition obtained by the production method of the present invention corresponds to a resist composition whose properties change in response to irradiation with active light or radiation. More specifically, the resist composition obtained by the production method of the present invention includes a semiconductor manufacturing process such as an IC (Integrated Circuit), a circuit board such as a liquid crystal or a thermal head, a molding structure for imprinting, and the like. The present invention relates to a resist composition used for a photofabrication process, a slab printing plate, or a production of an acid curable composition.
The pattern formed in the present invention can be used in an etching step, an ion implantation step, a bump electrode forming step, a rewiring forming step, a MEMS (Micro Electro Mechanical Systems), and the like.

[Pattern formation method]
Hereinafter, the pattern forming method of the present invention will be described.
The pattern forming method of the present invention
(I) A step of forming a resist film (sensitive light-sensitive or radiation-sensitive film) on the support by the resist composition obtained by the above-mentioned production method of the present invention (resist film forming step).
(Ii) A step (exposure step) of exposing the resist film (irradiating active light rays or radiation),
(Iii) A step of developing the exposed resist film with a developing solution (development step), and
Have.

The pattern forming method of the present invention is not particularly limited as long as it includes the steps (i) to (iii) above, and may further include the following steps.
In the pattern forming method of the present invention, the exposure method in the (ii) exposure step may be immersion exposure.
The pattern forming method of the present invention preferably includes (iv) preheating (PB: PreBake) step before the (ii) exposure step.
The pattern forming method of the present invention preferably includes (v) post-exposure heating (PEB: Post Exposure Bake) step after the (ii) exposure step and before the (iii) development step.
The pattern forming method of the present invention may include (ii) exposure steps a plurality of times.
The pattern forming method of the present invention may include (iv) a preheating step a plurality of times.
The pattern forming method of the present invention may include (v) a post-exposure heating step a plurality of times.

In the pattern forming method of the present invention, the above-mentioned (i) film forming step, (ii) exposure step, and (iii) developing step can be performed by a generally known method.
Further, if necessary, a resist underlayer film (for example, SOG (Spin On Glass), SOC (Spin On Carbon), and antireflection film) may be formed between the resist film and the support. As a material constituting the resist underlayer film, a known organic or inorganic material can be appropriately used.
A protective film (top coat) may be formed on the upper layer of the resist film. As the protective film, a known material can be appropriately used. For example, US Patent Application Publication No. 2007/0178407, US Patent Application Publication No. 2008/0085466, US Patent Application Publication No. 2007/0275326, US Patent Application Publication No. 2016/0299432, The composition for forming a protective film disclosed in US Patent Application Publication No. 2013/02444438 and International Patent Application Publication No. 2016/157988A can be preferably used. The composition for forming a protective film preferably contains the above-mentioned acid diffusion control agent.
A protective film may be formed on the upper layer of the resist film containing the above-mentioned hydrophobic resin.

The support is not particularly limited, and is generally used in a semiconductor manufacturing process such as an IC, a circuit board manufacturing process such as a liquid crystal or a thermal head, and other photolithography lithography processes. A substrate can be used. Specific examples of the support include an inorganic substrate such as silicon, SiO ₂ , and SiN.

The heating temperature is preferably 70 to 130 ° C., more preferably 80 to 130 ° C., still more preferably 80 to 120 ° C. in both the (iv) preheating step and the (v) post-exposure heating step.
The heating time is preferably 30 to 300 seconds, more preferably 30 to 180 seconds, still more preferably 30 to 90 seconds in both the (iv) preheating step and the (v) post-exposure heating step.
The heating can be performed by means provided in the exposure apparatus and the developing apparatus, and may be performed by using a hot plate or the like.

The wavelength of the light source used in the exposure process is not limited, and examples thereof include infrared light, visible light, ultraviolet light, far ultraviolet light, polar ultraviolet light (EUV), X-ray, and electron beam. Among these, far-ultraviolet light is preferable, and the wavelength thereof is preferably 250 nm or less, more preferably 220 nm or less, further preferably 1 to 200 nm. Specifically, KrF excimer laser (248 nm), ArF excimer laser (193 nm), _{F 2} excimer laser (157 nm), X-ray, EUV (13 nm), or an electron beam or the like, KrF excimer laser, ArF excimer laser, EUV or electron beam is preferable.

(Iii) In the developing step, it may be an alkaline developer or a developer containing an organic solvent (hereinafter, also referred to as an organic developer).

As the alkaline developer, a quaternary ammonium salt typified by tetramethylammonium hydroxide is usually used, but in addition to this, alkaline aqueous solutions such as inorganic alkalis, primary to tertiary amines, alcohol amines, and cyclic amines are also available. It can be used.
Further, the alkaline developer may contain an appropriate amount of alcohols and / or a surfactant. The alkali concentration of the alkaline developer is usually 0.1 to 20% by mass. The pH of the alkaline developer is usually 10 to 15.
The time for developing with an alkaline developer is usually 10 to 300 seconds.
The alkali concentration, pH, and development time of the alkaline developer can be appropriately adjusted according to the pattern to be formed.

The organic developer is a developer containing at least one organic solvent selected from the group consisting of a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, an ether solvent, and a hydrocarbon solvent. Is preferable.

Examples of the ketone solvent include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methylamyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, and diisobutyl ketone. Cyclohexanone, methylcyclohexanone, phenylacetone, methylethylketone, methylisobutylketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methylnaphthylketone, isophorone, propylene carbonate and the like can be mentioned.

Examples of the ester solvent include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, and diethylene glycol monoethyl. Ether acetate, ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butane Examples thereof include butyl acid acid, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, butyl propionate and the like.

As the alcohol solvent, the amide solvent, the ether solvent, and the hydrocarbon solvent, the solvents disclosed in paragraphs [0715] to [0718] of US Patent Application Publication No. 2016/0070167A1 can be used.

A plurality of the above solvents may be mixed, or may be mixed with a solvent other than the above or water. The water content of the developer as a whole is preferably less than 50% by mass, more preferably less than 20% by mass, further preferably less than 10% by mass, most preferably less than 0 to 5% by mass, and substantially free of water. Is particularly preferable.
The content of the organic solvent in the organic developer is preferably 50 to 100% by mass, more preferably 80 to 100% by mass, further preferably 90 to 100% by mass, and 95 to 100% by mass with respect to the total amount of the developer. % Is particularly preferable.

The organic developer may contain an appropriate amount of a known surfactant, if necessary.

The content of the surfactant is usually 0.001 to 5% by mass, preferably 0.005 to 2% by mass, more preferably 0.01 to 0.5% by mass, based on the total amount of the developing solution.

The organic developer may contain the acid diffusion control agent described above.

Examples of the developing method include a method of immersing the substrate in a tank filled with a developing solution for a certain period of time (dip method), a method of raising the developing solution on the surface of the substrate by surface tension and allowing it to stand still for a certain period of time (paddle method), and a substrate. Examples include a method of spraying the developer on the surface (spray method) or a method of continuing to discharge the developer while scanning the developer discharge nozzle at a constant speed on a substrate rotating at a constant speed (dynamic discharge method). Be done.

A step of developing with an alkaline aqueous solution (alkaline developing step) and a step of developing with a developer containing an organic solvent (organic solvent developing step) may be combined. As a result, the pattern can be formed without dissolving only the region of the intermediate exposure intensity, so that a finer pattern can be formed.

(Iii) It is preferable to include a step of washing with a rinsing solution (rinsing step) after the developing step.

For example, pure water can be used as the rinsing solution used in the rinsing step after the developing step using the alkaline developer. Pure water may contain an appropriate amount of a surfactant. In this case, after the developing step or the rinsing step, a process of removing the developing solution or the rinsing solution adhering to the pattern with a supercritical fluid may be added. Further, after the rinsing treatment or the treatment with the supercritical fluid, a heat treatment may be performed to remove the water remaining in the pattern.

The rinsing solution used in the rinsing step after the developing step using the developing solution containing an organic solvent is not particularly limited as long as it does not dissolve the pattern, and a general solution containing an organic solvent can be used. As the rinsing solution, use a rinsing solution containing at least one organic solvent selected from the group consisting of a hydrocarbon solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, and an ether solvent. Is preferable.
Specific examples of the hydrocarbon solvent, the ketone solvent, the ester solvent, the alcohol solvent, the amide solvent, and the ether solvent include the same as those described for the developing solution containing the organic solvent.
As the rinsing solution used in the rinsing step in this case, a rinsing solution containing a monohydric alcohol is more preferable.

Examples of the monohydric alcohol used in the rinsing step include linear, branched, and cyclic monohydric alcohols. Specifically, 1-butanol, 2-butanol, 3-methyl-1-butanol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 1-hexanol, 4-methyl-2-pentanol, 1 -Heptanol, 1-octanol, 2-hexanol, cyclopentanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, and methylisobutylcarbinol can be mentioned. Examples of monohydric alcohols having 5 or more carbon atoms include 1-hexanol, 2-hexanol, 4-methyl-2-pentanol, 1-pentanol, 3-methyl-1-butanol, methyl isobutyl carbinol and the like. ..

A plurality of each component may be mixed, or may be mixed and used with an organic solvent other than the above.
The water content in the rinse solution is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less. Good development characteristics can be obtained by setting the water content to 10% by mass or less.

The rinse solution may contain an appropriate amount of a surfactant.
In the rinsing step, the substrate developed with an organic developer is washed with a rinsing solution containing an organic solvent. The cleaning treatment method is not particularly limited, and for example, a method of continuously discharging the rinse liquid onto a substrate rotating at a constant speed (rotary coating method), or a method of immersing the substrate in a tank filled with the rinse liquid for a certain period of time. Examples thereof include a method (dip method) and a method of spraying a rinse liquid on the substrate surface (spray method). Above all, it is preferable to perform the cleaning treatment by the rotary coating method, and after cleaning, rotate the substrate at a rotation speed of 2,000 to 4,000 rpm to remove the rinse liquid from the substrate. It is also preferable to include a heating step (Post Bake) after the rinsing step. This heating step removes the developer and rinse liquid remaining between and inside the patterns. In the heating step after the rinsing step, the heating temperature is usually 40 to 160 ° C., preferably 70 to 95 ° C., and the heating time is usually 10 seconds to 3 minutes, preferably 30 seconds to 90 seconds.

The resist composition obtained by the production method of the present invention, and various materials used in the pattern forming method of the present invention (for example, a developing solution, a rinsing solution, an antireflection film forming composition, or a top coat forming composition). Etc.) preferably do not contain impurities such as metal components, isomers, and residual monomers. The content of these impurities contained in the above-mentioned various materials is preferably 1 ppm or less, more preferably 100 ppt or less, further preferably 10 ppt or less, and substantially not contained (below the detection limit of the measuring device). Is particularly preferable.

Examples of the method for removing impurities such as metals from the above-mentioned various materials include filtration using a filter. The filter pore size is preferably 10 nm or less, more preferably 5 nm or less, and even more preferably 3 nm or less. As the material of the filter, a filter made of polytetrafluoroethylene, polyethylene, or nylon is preferable. The filter may be one that has been pre-cleaned with an organic solvent. Filter In the filtration step, a plurality of types of filters may be connected in series or in parallel. When a plurality of types of filters are used, filters having different pore diameters and / or materials may be used in combination. Further, various materials may be filtered a plurality of times, and the step of filtering the various materials a plurality of times may be a circulation filtration step. As the filter, it is preferable that the eluate is reduced as disclosed in Japanese Patent Application Publication No. 2016-201426 (Japanese Patent Laid-Open No. 2016-201426).
In addition to filter filtration, impurities may be removed by an adsorbent, and filter filtration and an adsorbent may be used in combination. As the adsorbent, a known adsorbent can be used, and for example, an inorganic adsorbent such as silica gel or zeolite, or an organic adsorbent such as activated carbon can be used. Examples of the metal adsorbent include those disclosed in Japanese Patent Application Publication No. 2016-206500 (Japanese Patent Laid-Open No. 2016-206500).
Further, as a method for reducing impurities such as metals contained in the various materials, a raw material having a low metal content is selected as a raw material constituting the various materials, and filter filtration is performed on the raw materials constituting the various materials. Alternatively, a method such as lining the inside of the apparatus with Teflon (registered trademark) or the like to perform distillation under conditions in which contamination is suppressed as much as possible can be mentioned. It is also preferable to apply glass lining treatment to all processes of the manufacturing equipment for synthesizing various materials (resin, photoacid generator, etc.) of the resist component in order to reduce impurities such as metals to the order of ppt. The preferred conditions for filter filtration performed on the raw materials constituting the various materials are the same as those described above.

In order to prevent contamination of the above-mentioned various materials, U.S. Patent Application Publication No. 2015/0227049, Japanese Patent Application Publication No. 2015-123351 (Japanese Patent Laid-Open No. 2015-123351), Japanese Patent It is preferably stored in the container described in Application Publication No. 2017-13804 (Japanese Patent Laid-Open No. 2017-13804) and the like.

A method for improving the surface roughness of the pattern may be applied to the pattern formed by the pattern forming method of the present invention. As a method for improving the surface roughness of the pattern, for example, a method of treating the pattern with a plasma of a gas containing hydrogen disclosed in US Patent Application Publication No. 2015/0104957 can be mentioned. In addition, Japanese Patent Application Publication No. 2004-235468 (Japanese Patent Laid-Open No. 2004-235468), US Patent Application Publication No. 2010/0020297, Proc. of SPIE Vol. A known method as described in 8328 83280N-1 “EUV Resist Curing Technology for LWR Reduction and Etch Sensitivity Enhancement” may be applied.
Further, the pattern formed by the above method is a spacer process disclosed in, for example, Japanese Patent Application Publication No. 1991-270227 (Japanese Patent Application Laid-Open No. 3-270227) and US Patent Application Publication No. 2013/209941. Can be used as a core material (Core).

[Manufacturing method of electronic device]
The present invention also relates to a method for manufacturing an electronic device, including the above-mentioned pattern forming method. The electronic device manufactured by the method for manufacturing an electronic device of the present invention is suitably mounted on an electrical and electronic device (for example, home appliances, OA (Office Automation) related devices, media related devices, optical devices, communication devices, etc.). Will be done.

The present invention will be described in more detail below based on examples. The materials, amounts used, proportions, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as limiting by the examples shown below.

[Synthesis of resins (P-AP1) to (P-AP6), resins (P-AN1) to (P-AN6), and resins (P-KP1) to (P-KP6), and polymer solutions (P-AN6). AP1-0) to (P-AP1-6), polymer solutions (P-AN1-0) to (P-AN1-6), and polymer solutions (P-KP1-0) to (P-KP1-6) Preparation]
[Synthesis of resin (P-AP1) and preparation of polymer solution (P-AP1-0)]
A mixed solvent of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether was placed in a flask under a nitrogen stream and heated to 80 ° C. (solvent 1). Next, the monomers corresponding to each repeating unit of the resin P-AP1 shown below were mixed in a mixed solvent of 6/4 (mass ratio) of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether at a molar ratio of 40/60, respectively. It was dissolved and a monomer solution was prepared. Further, a polymerization initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the dissolved solution was added dropwise to the solvent 1 over 6 hours. After completion of the dropping, the reaction was further carried out at 80 ° C. for 2 hours. The reaction solution was allowed to cool, poured into hexane / ethyl acetate, and the precipitated powder was collected by filtration and dried to obtain a resin (P-AP1). The weight average molecular weight of the obtained resin (P-AP1) was 8,000, and the dispersity (Mw / Mn) was 1.5. Further, the resin (P-AP1) was dissolved in propylene glycol monomethyl ether acetate to obtain a polymer solution (P-AP1-0) of 15% by mass.

[Synthesis of resins (P-AP2) to (P-AP6), resins (P-AN1) to (P-AN6), and resins (P-KP1) to (P-KP6), and polymer solutions (P-). AP2-0) to (P-AP6-0), polymer solutions (P-AN1-0) to (P-AN6-0), and polymer solutions (P-KP1-0) to (P-KP6-0) Preparation]
Resins (P-AP2) to (P-AP6) and resins shown in Table 1 according to the method described in [Synthesis of resin (P-AP1) and preparation of polymer solution (P-AP1-0)] described above. (P-AN1) to (P-AN6) and resins (P-KP1) to (P-KP6) were synthesized. Further, by mixing each of the obtained resins and the solvent shown in Table 1 so as to have the solid content concentration shown in Table 1, the polymer solutions (P-AP2-0) to (P-AP6-0). , Polymer solutions (P-AN1-0) to (P-AN6-0), and polymer solutions (P-KP1-0) to (P-KP6-0) were prepared.
The structures of the resins (P-AP2) to (P-KP6) are shown below. In addition, Table 1 shows the weight average molecular weight (Mw) and the degree of dispersion of the resins (P-AP2) to (P-KP6). In each structure of the resins (P-AP2) to (P-KP6) shown below, the composition ratio of each repeating unit is intended to be a molar ratio.

[Preparation of resist composition]
[Step A (Polymer solution filtration step)]
Step A (filtering step of the polymer solution) was carried out on the obtained polymer solutions (P-AP1-0) to (P-KP6-0) according to the procedure shown below, and the polymer solution (P-AP1- 1)-(P-KP6-1) were obtained.

<Purification Example 1: Preparation of Polymer Solution (P-AP1-1)>
First, a filtration facility composed of a first filter of a nylon film (Pall-made Ultipleats / P-nylon, pore diameter 0.02 μm) was prepared.
Next, the prepared polymer solution (P-AP1-0) was passed through the first filter under the condition of a linear velocity of 132 L / (hr · m ² ) in an environment of 22 ° C. to obtain a polymer solution (P-AP1-0). P-AP1-1) was obtained. In addition, purification example 1 corresponds to the form in which step A includes the above-mentioned step X once.

<Purification Example 2: Preparation of Polymer Solution (P-AP1-2)>
First, the first filter of nylon film (Pall's Ultipleated P-nylon, pore diameter 0.02 μm) and the second filter of polyethylene film (Microgard Plus made by Entegris, pore diameter 0.005 μm) are connected in series. I prepared a filtration facility.
Next, the prepared polymer solution (P-AP1-0) is passed through the first filter to the second filter in this order under the condition of a linear velocity of 132 L / (hr · m ² ) in an environment of 22 ° C. As a result, a polymer solution (P-AP1-2) was obtained. In addition, the purification example 2 corresponds to the form in which the step A includes the above-mentioned step X twice or more, and specifically corresponds to the above-mentioned step (2). The first filter corresponds to the above-mentioned filter X1, and the second filter corresponds to the above-mentioned filter X2.

<Purification Example 3: Preparation of Polymer Solution (P-AP1-3)>
First, the first filter of nylon film (Pall's Ultipleated P-nylon, pore diameter 0.02 μm) and the second filter of polyethylene film (Microgard Plus made by Entegris, pore diameter 0.005 μm) are connected in series. I prepared a filtration facility.
Next, the prepared polymer solution (P-AP1-0) was applied 5 times in the order of the first filter to the second filter under the condition of a linear velocity of 132 L / (hr · m ² ) in an environment of 22 ° C. The polymer solution (P-AP1-3) was obtained by repeating the liquid passing. In addition, purification example 3 corresponds to the form in which step A includes the above-mentioned step X twice or more, and specifically corresponds to the above-mentioned step (2). The first filter corresponds to the above-mentioned filter X1, and the second filter corresponds to the above-mentioned filter X2.

<Purification Examples 4 to 21>
The polymer solutions ((P-AP1-4) to (P-KP6-1)) shown in Table 2 were obtained by the same method except for the polymer solution to be used, the filter, the linear velocity, and the temperature.
In Table 2, "PTFE" in Purification Example 4 is intended to be polytetrafluoroethylene. Specifically, it is "Torrento X" manufactured by Entegris.

[Measurement of specific metal atom content in polymer solution]
The polymer solutions (P-AP1-0) to (P-KP6-1) obtained in [Step A (Filtration step of polymer solution)] described above, and [Step A (Filtration step of polymer solution)] described above. The total content (mass ppb) of specific metal atoms in the solution was measured for the polymer solutions (P-AP1-0), (P-AP2-0), and (P-AP3-0) that were not subjected to the above. ..
Specifically, using ICP-MS, Metal-7500cs manufactured by Agilent Technologies, Na, K, Ca, Fe, Cu, Mg, Mn, Al, Li, Cr, Ni, Sn, Zn, Ag, As. , Au, Ba, Cd, Co, Pb, V, W, Zr, and Mo, the total content of each metal atom was measured, and from the obtained values, the content of the specific metal atom (mass) with respect to the total mass of the solution. ppb) was calculated. The measurement results are shown in Table 3.

From the results in Table 3, it is clear that when the acid-decomposable resin contains one or more of a carbonate structure and a sultone structure, the effect of reducing specific metal impurities in step A is more excellent.

[Step B (Preparation of resist composition)]
<Preparation of resist compositions R-1 to R-21 and RC-1 to RC-3>
First, a first filter of nylon membrane (pore diameter; 0.01 μm), a second filter of polyethylene membrane (pore diameter; 0.002 μm), and a third filter of polyethylene membrane (pore diameter; 0.002 μm) are used. Filtering equipment connected in series in this order was prepared.
Next, each component is mixed according to the formulation shown in Table 4 below, and the obtained mixed solution is passed through the filtration equipment, whereby the resist composition (R-1 to R-) having a total solid content concentration shown in Table 4 is passed. 21, RC-1 to RC-3) were obtained.

The structure of each component used in Table 4 is shown below.

(Photoacid generator)

(Basic compound)

(Additive)

A-3: Megafuck R-41 (manufactured by DIC Corporation) (fluorine-based)

(solvent)
SL-1: Propylene glycol monomethyl ether acetate (PGMEA)
SL-2: Propylene glycol monomethyl ether (PGME)
SL-3: γ-BL (GBL)
SL-4: Cyclohexanone

[Pattern formation (ArF exposure, positive development) and evaluation]
[Examples AP-1 to AP-9, Comparative Example AP-1]
The composition for forming an organic antireflection film ARC29SR (manufactured by Nissan Chemical Industries, Ltd.) was applied onto a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a film thickness of 95 nm. The resist compositions R-1 to R-9 and RC-1 were each applied thereto, and the mixture was baked at 90 ° C. for 60 seconds to form a resist film having a film thickness of 85 nm. A halftone exposure mask with 6% transmittance was used for the obtained wafer using an ArF excimer laser immersion scanner (ASML XT1700i, NA1.20, Dipole, outer sigma 0.981, inner sigma 0.895, Y deflection). Pattern exposure was performed via (line / space = 1/1). Pure water was used as the immersion liquid. Then, after heating at 100 ° C. for 60 seconds, a pattern having a pitch of 130 nm and a line width of 65 nm was obtained by paddling with a tetramethylammonium aqueous solution (2.38% by mass) for 30 seconds and developing (positive type development). Defects on the obtained resist pattern were inspected with Uvision 5 manufactured by AMAT, and the number of bridge defects (pieces / cm ² ) was counted. The results are shown in Table 5.

From the results in Table 5, it is clear that when the resist composition obtained by the production method of the example is used, the bridge defects generated on the developed pattern can be suppressed (the number of bridge defects generated is small).
Further, from the comparison of Examples of Examples AP-1 to AP-9, when the acid-degradable resin contained in the resist composition contains at least one of a carbonate structure and a sultone structure, it is generated on the pattern after development. It is clear that the bridging defects can be further suppressed (comparison between Examples AP-1 to AP-7 and Examples AP-8 and AP-9).
On the other hand, when the resist composition obtained by the production method of the comparative example is used, the bridge defects generated on the developed pattern cannot be suppressed.

[Pattern formation (ArF exposure, negative development) and evaluation]
[Examples AN-1 to AN-6, Comparative Example AN-1]
The composition for forming an organic antireflection film ARC29SR (manufactured by Nissan Chemical Industries, Ltd.) was applied onto a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a film thickness of 95 nm. The resist compositions R-10 to R-15 and RC-2 were applied thereto and baked at 90 ° C. for 60 seconds to form a resist film having a film thickness of 85 nm. A halftone exposure mask with 6% transmittance was used for the obtained wafer using an ArF excimer laser immersion scanner (ASML XT1700i, NA1.20, Dipole, outer sigma 0.981, inner sigma 0.895, Y deflection). Pattern exposure was performed via (line / space = 1/1). Pure water was used as the immersion liquid. Then, it was heated at 100 ° C. for 60 seconds and then paddled with butyl acetate for 60 seconds for development (negative type development) to obtain a pattern having a pitch of 130 nm and a line width of 65 nm. Defects on the obtained resist pattern were inspected with Uvision 5 manufactured by AMAT, and the number of bridge defects (pieces / cm ² ) was counted. The results are shown in Table 6.

From the results in Table 6, it is clear that when the resist composition obtained by the production method of the example is used, the bridge defects generated on the developed pattern can be suppressed (the number of bridge defects generated is small).
Further, from the comparison of Examples of Examples AN-1 to AN-6, when the acid-decomposable resin contained in the resist composition contains one or more of a carbonate structure and a sultone structure, it is generated on the pattern after development. It is clear that the bridging defects can be further suppressed (comparison between Examples AN-1 to AN-4 and Examples AN-5 and AN-6).
On the other hand, when the resist composition obtained by the production method of the comparative example is used, the bridge defects generated on the developed pattern cannot be suppressed.

[Pattern formation (KrF exposure, positive development) and evaluation]
[Examples KP-1 to KP-6, Comparative Example KP-1]
An organic antireflection film forming composition DUV42 (manufactured by Brewer Science Co., Ltd.) was applied onto a silicon wafer and baked at 205 ° C. for 60 seconds to form an antireflection film having a film thickness of 64 nm. The resist compositions R-16 to 21 and RC-3 were applied thereto and baked at 130 ° C. for 60 seconds to form a resist film having a film thickness of 600 nm. The obtained wafer was used with a KrF excimer laser (ASML PASS, NA0.7, Dipole, outer sigma 0.8, inner sigma 0.7) and passed through a binary exposure mask (line / space = 1/1). Then, pattern exposure was performed. Then, after heating at 130 ° C. for 60 seconds, a pattern having a pitch of 400 nm and a line width of 200 nm was obtained by paddling with a tetramethylammonium aqueous solution (2.38% by mass) for 60 seconds and developing (positive development). Defects on the obtained resist pattern were inspected for defects with 2360 manufactured by KLA, and the number of bridge defects (pieces / cm ² ) was counted.

From the results in Table 7, it is clear that when the resist composition obtained by the production method of the example is used, the bridge defects generated on the developed pattern can be suppressed (the number of bridge defects generated is small).
Further, from the comparison of Examples KP-1 to KP-6, when the acid-decomposable resin contained in the resist composition contains one or more of a carbonate structure and a sultone structure, it is generated on the developed pattern. It is clear that the bridging defects can be further suppressed (comparison between Examples KP-1 to KP-2 and Examples KP-3 to KP-6).
On the other hand, when the resist composition obtained by the production method of the comparative example is used, the bridge defects generated on the developed pattern cannot be suppressed.

Claims

A method for producing a sensitive light-sensitive or radiation-sensitive resin composition used in a semiconductor device manufacturing process.
Step A of purifying a polymer solution containing a resin and a solvent which are decomposed by the action of an acid and whose polarity is increased.
A step B of preparing a sensitive light-sensitive or radiation-sensitive resin composition by adding a compound that generates an acid by irradiation with active light or radiation to the polymer solution that has undergone the step A is included.
A method for producing a sensitive light-sensitive or radiation-sensitive resin composition, wherein the step A comprises a step X in which the polymer solution is passed through a filter X and filtered.
The first aspect of claim 1, wherein the filter X is selected from the group consisting of a nylon film having a pore size of 0.03 μm or less, a polyolefin resin film having a pore size of 0.01 μm or less, and a fluororesin film having a pore size of 0.01 μm or less. A method for producing a sensitive light-sensitive or radiation-sensitive resin composition.
The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to claim 1 or 2, wherein the differential pressure of the filter X is 0.3 MPa or less.
The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 3, wherein the step X is carried out in a temperature environment of 15 to 25 ° C.
The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 4, wherein the step A includes the step X twice or more.
The step A is
A step X0 in which the polymer solution is passed through the filter X0 and filtered, and a step X1 in which the polymer solution passed through the step X0 is passed through the filter X1 and filtered is included.
A step X1 in which the polymer solution is passed through the filter X1 and filtered, and a step X2 in which the polymer solution passed through the step X1 is passed through the filter X2 and filtered is included.
A step X0 in which the polymer solution is passed through the filter X0 and filtered, a step X1 in which the polymer solution passed through the step X0 is passed through the filter X1 and filtered, and the polymer solution passed through the step X1 is passed through the filter X2. Including step X2 of letting and filtering
The filter X0 and the filter X2 are filters different from the filter X1, and are selected from a polyolefin resin film having a pore diameter of 0.01 μm or less and a fluororesin film having a pore diameter of 0.01 μm or less, claims 1 to 4. The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to any one of the above.
The step A is
The polymer solution comprises a step X0 of passing the polymer solution through the filter X0 and filtering the polymer solution, and a step X1 of passing the polymer solution through the step X0 and filtering the polymer solution through the filter X1 and passing through the step X1. Then, once again, the step of carrying out the step X0 and the step X1 is included one or more times.
The polymer solution comprises a step X1 in which the polymer solution is passed through the filter X1 and filtered, and a step X2 in which the polymer solution through the step X1 is passed through the filter X2 and filtered, and the polymer solution has undergone the step X2. Then, the step of carrying out the step X1 and the step X2 is included once or more, or
A step X0 in which the polymer solution is passed through the filter X0 and filtered, a step X1 in which the polymer solution through the step X0 is passed through the filter X1 and filtered, and the polymer solution through the step X1 is passed through the filter X2. 6. The step 6 includes the step X2 of performing the step X2 and the step X2, and the step of performing the step X0, the step X1 and the X2 again with respect to the polymer solution that has undergone the step X2. The method for producing a sensitive light-sensitive or radiation-sensitive resin composition according to the above method.
The actinic or radiation-sensitive resin composition according to claim 6 or 7, wherein the differential pressure of the filter X0, the differential pressure of the filter X1, and the differential pressure of the filter X2 are all 0.3 MPa or less. Manufacturing method of things.
The one according to any one of claims 1 to 8, wherein the resin that is decomposed by the action of the acid and whose polarity is increased includes a resin containing a repeating unit derived from at least one of an acrylic acid ester and a methacrylic acid ester. A method for producing a sensitive light-sensitive or radiation-sensitive resin composition.
The actinic or radiation-sensitive resin composition according to any one of claims 1 to 9, wherein the resin whose polarity is increased by the action of the acid contains one or more of a carbonate structure and a sultone structure. How to make things.
The sensitive light-sensitive or radiation-sensitive resin composition produced by the method for producing the sensitive light-sensitive or radiation-sensitive resin composition according to any one of claims 1 to 10 is used on a support. The process of forming the resist film and
The step of exposing the resist film and
A pattern forming method comprising a step of developing the exposed resist film with a developing solution.
A method for manufacturing an electronic device, including the pattern forming method according to claim 11.