WO2021054284A1

WO2021054284A1 - Pattern formation composition and pattern formation method

Info

Publication number: WO2021054284A1
Application number: PCT/JP2020/034708
Authority: WO
Inventors: 田中　宏樹; 泰明田中
Original assignee: 王子ホールディングス株式会社
Priority date: 2019-09-20
Filing date: 2020-09-14
Publication date: 2021-03-25
Also published as: TW202119131A

Abstract

The present invention addresses the problem of providing a pattern formation composition that makes it possible to form a pattern formation film that exhibits excellent etchability. The present invention relates to a pattern formation composition that includes a polymer. When Pr is the free volume radius of the polymer and Mr is the nuclear radius of a metal that is introduced when a pattern is formed from the pattern formation composition, 2≤Pr/Mr≤3.3.

Description

Pattern-forming composition and pattern-forming method

The present invention relates to a pattern-forming composition and a pattern-forming method.

Electronic devices such as semiconductors are required to have higher definition by miniaturization. In addition, diversification of shapes of semiconductor device patterns is also being studied. Examples of such a pattern forming method include a double patterning method, a lithography method using an electron beam, a nanoimprint method, and an induced self-assembling material (Directed Self Assembly, hereinafter also referred to as a pattern forming self-assembling composition). The pattern formation method by self-assembly used is known.

Since the self-assembling composition for pattern formation performs self-assembling by performing phase separation, an expensive electron beam drawing apparatus is not required, and the patterning process complicated as seen in the double patterning method is not complicated, so that the cost is increased. There are the above merits. As a self-assembling composition for pattern formation, for example, diblock copolymers such as polystyrene-polymethylmethacrylate (PS-PMMA) are known (for example, Patent Document 1).

It is also being considered to use a material other than PS-PMMA as the self-assembling composition for pattern formation. For example, Patent Document 2 discloses a self-assembling composition for pattern formation having a styrene-based polymer, an acrylic-based polymer, or the like as a main chain and having a group containing a heteroatom at the end thereof.

US2012 / 0241411 A1 Japanese Unexamined Patent Publication No. 2014-5325

After forming a pattern using the self-assembling composition for pattern formation as described above, an etching step may be provided in which the pattern is used as a protective film and the pattern shape is further processed on the silicon wafer substrate. However, in the conventional method, the etching processability at the time of processing the pattern shape on the substrate may be inferior, which has been a problem.

Therefore, in order to solve the problems of the prior art, the present inventors have studied for the purpose of providing a pattern forming composition capable of forming a pattern forming film exhibiting excellent etching processability. I proceeded.

Specifically, the present invention has the following configuration.

[1] A pattern-forming composition containing a polymer.
Let Pr be the free volume radius of the polymer
When the nuclear radius of the metal introduced when forming a pattern from the pattern forming composition is Mr.
A composition for pattern formation that satisfies the condition of 2 ≦ Pr / Mr ≦ 3.3.
[2] When the pattern-forming composition is applied onto a substrate to form a pattern-forming film having a thickness of 300 nm, and a metal gas is introduced into the pattern-forming film under a pressure of 500 Pa for 300 seconds.
The total content of metal contained in the pattern forming film is 4.0 atom% or more.
When the maximum metal content in the thickness direction of the pattern forming film is Aatom% and the metal content at the midpoint in the thickness direction of the pattern forming film is Batom%, the A / B value is 10.0 or less. , [1]. The pattern-forming composition.
[3] The pattern-forming composition according to [1] or [2], wherein the polymer contains a unit derived from a sugar derivative.
[4] The pattern according to [3], wherein the unit derived from the sugar derivative includes at least one selected from the structure represented by the following general formula (103) and the structure represented by the following general formula (104). Composition for formation;

In the general formulas (103) and (104), R ¹ independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group, an acyl group, an aryl group, a trimethylsilyl group or a phosphoryl group, and a plurality of them. Some R 1s may be the same or different; R ⁵ represents a hydrogen atom or an alkyl group; X ¹ and Y ¹ each independently represent a single bond or a linking group; r represents an integer greater than or ^{equal to 1.} represents, * or mark represents any one of the binding sites of R ¹ when r is 2 or more, or any one of the binding sites of the oxygen atom R ¹ in place of R ¹ is attached Represent.
[5] The pattern-forming composition according to [4], wherein the polymer further has a structure represented by the following general formula (105);

In the general formula (105), W ¹ represents a carbon atom or a silicon atom, and W ² represents -CR _2- , -O-, -S- or -SiR _2- (where R is a hydrogen atom or carbon. Represents an alkyl group having a number of 1 to 5, and a plurality of Rs may be the same or different); R ¹¹ represents a hydrogen atom, an alkyl group having 1 or more and 3 or less carbon atoms or a hydroxyl group, and R ¹² Represents a hydrogen atom, a hydroxyl group, an acetyl group, a methoxycarbonyl group, an aryl group, an allyl group, a glycidyl ether group, a glycidyl ester group, an isocyanate ester group or a pyridyl group.
[6] The pattern formation according to any one of [1] to [5], wherein the polymer contains a unit derived from a sugar derivative, and the content of the unit derived from the sugar derivative in the polymer is 60 to 90% by mass. Composition for.
[7] The pattern-forming composition according to any one of [1] to [6], which is a pattern-forming mask material.
[8] A step of applying a pattern-forming composition containing a polymer onto a substrate to form a pattern-forming film, and
A pattern forming method including a step of introducing a metal into at least a part of a pattern forming film to obtain a metal-containing pattern forming film.
Let Pr be the free volume radius of the polymer
When the nucleus radius of the metal is Mr,
A pattern forming method that satisfies the condition of 2 ≦ Pr / Mr ≦ 3.3.
[9] The total content of the metal contained in the metal-containing pattern forming film is 4.0 atom% or more.
When the maximum metal content in the thickness direction of the metal-containing pattern forming film is Aatom% and the metal content at the midpoint in the thickness direction of the pattern forming film is Batom%, the A / B value is 10.0 or less. The pattern forming method according to [8].
[10] The pattern forming method according to [8] or [9], further comprising a step of forming a pattern on the pattern forming film after the step of forming the pattern forming film.
[11] The pattern forming method according to any one of [8] to [10], further comprising an etching step after the step of obtaining a metal-containing pattern forming film.

According to the present invention, it is possible to improve the etching processability when processing a pattern shape on a substrate after forming a pattern forming film from a pattern forming composition.

FIG. 1 is a graph showing the depth profile (XPS measurement) of the Al content in the pattern forming film obtained in Examples and Comparative Examples. FIG. 2 is a schematic view illustrating a process of forming a pattern on a substrate.

Hereinafter, the present invention will be described in detail. The description of the constituent elements described below may be based on typical embodiments or specific examples, but the present invention is not limited to such embodiments. It should be noted that, with respect to a substituent for which substitution / non-substitution is not specified in the present specification, it means that the group may have an arbitrary substituent.

(Composition for pattern formation)
The present invention relates to a pattern-forming composition containing a polymer. A metal is introduced into the pattern-forming film formed from the pattern-forming composition of the present invention. At this time, the nuclear radius of the metal introduced into the pattern-forming film is Mr, and the pattern-forming film of the present invention is used. When the free volume radius of the polymer contained in the composition is Pr, the condition of 2 ≦ Pr / Mr ≦ 3.3 is satisfied. As described above, the present invention relates to a pattern forming composition containing a polymer having a free volume radius (Pr) satisfying the above conditions with respect to the nuclear radius (Mr) of the metal introduced in the pattern forming step. It is a thing.

Here, the nuclear radius (Mr) of the metal introduced into the pattern-forming film is determined by E Clementi, D L Ramondo, WP Reinhardt (1963), J Chem Phys. It is a value quoted from 38: 2686. Even when the metal introduced into the pattern forming film is a _{metal oxide such as Al 2} O ₃ , the nuclear radius of the metal element (Al) may satisfy the above conditions.

The free volume radius (Pr) of the polymer is a value measured as follows. First, a copolymer solution sample is obtained by dissolving in PGMEA so that the polymer content is 3% by mass and p-toluenesulfonic acid is 0.3% by mass. Then, the copolymer solution sample is spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness is 500 nm, it is fired on a hot plate at 230 ° C. for 5 minutes to form a pattern-forming film. Next, the free volume radius (Pr) of the polymer is calculated by measuring the positron annihilation lifetime of the formed pattern-forming film. Specifically, the pattern-forming film is installed in the positron annihilation lifetime measuring device. Using 22Na based positron beam as positron source, using BaF ₂ made scintillator and a photomultiplier tube as a γ-ray detector, measuring a positron annihilation lifetime under the following conditions. As the positron annihilation life measuring device, for example, a small positron beam generator PALS-200A manufactured by Fuji Invac can be used.
Device constants: 263 to 272 ps, 24.55 ps / ch
Beam intensity: 1.5 keV
Measurement depth: 0 to 25 μm (estimated)
Measurement temperature: Room temperature Measurement atmosphere: Vacuum Total number of counts: Approximately 5,000,000 counts Sample pretreatment: Vacuum degassing at room temperature The positron annihilation lifetime curve obtained above is analyzed by the nonlinear minimum square program POSITRONFIT to calculate the average free volume radius. , The free volume radius (Pr) of the polymer.

The preferred free volume radius (Pr) of the polymer depends on the nuclear radius of the metal introduced into the pattern forming film, but for example, the free volume radius (Pr) of the polymer is preferably 0.10 nm or more, and is 0. It is more preferably 20 nm or more, and further preferably 0.25 nm or more. The free volume radius (Pr) of the polymer is preferably 0.50 nm or less, more preferably 0.40 nm or less, and further preferably 0.35 nm or less. In order to keep the free volume radius (Pr) of the polymer within the above range, for example, the content of the unit derived from the sugar derivative constituting the polymer is adjusted, the degree of polymerization of the sugar portion and the length of the sugar chain are adjusted. It is conceivable to adjust or appropriately adjust the content of the constituent units other than the unit derived from the sugar derivative.

The value of Pr / Mr may be 2 or more, preferably 2.1 or more, more preferably 2.2 or more, further preferably 2.3 or more, and 2.4 or more. Is particularly preferable. The Pr / Mr value may be 3.3 or less, preferably 3.2 or less, more preferably 3.1 or less, and even more preferably 3.0 or less. By setting the Pr / Mr value within the above range, the permeability of the metal to the pattern forming film can be enhanced, and thus a high-strength pattern forming film can be formed. Therefore, it is possible to more effectively enhance the etching processability when processing the pattern shape on the substrate after forming the pattern forming film from the pattern forming composition.

Here, the etching processability can be evaluated by calculating the etching selectivity, and the etching selectivity can be calculated, for example, as follows. In order to calculate the etching selectivity, first, a copolymer solution sample is obtained by dissolving in PGMEA so that the polymer content is 3% by mass and p-toluenesulfonic acid is 0.3% by mass. Then, the copolymer solution sample is spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness is 300 nm, it is fired on a hot plate at 230 ° C. for 1 minute to form a pattern-forming film. Next, the mask is masked with an ArF excimer laser exposure machine so as to have a line-and-space shape (line width 100 nm, space width 100 nm), and exposure is performed using a commercially available ArF resist. Then, after firing on a hot plate at 105 ° C. for 1 minute, a line-and-space pattern is produced by immersing the developing solution. Next, this pattern sample is subjected to oxygen plasma treatment (100 sccm, 4 Pa, 100 W, 60 seconds) on the substrate by an ICP plasma etching apparatus (manufactured by Tokyo Electron Limited) to form a line and space pattern on the pattern forming film. To do. Then, this pattern-forming film was placed in ALD (atomic layer deposition apparatus: SUNALE R-100B manufactured by PICUSAN), and TMA (trimethylaluminum, Al (CH ₃ ) ₃ ) gas was introduced at 95 ° C. for 300 seconds. , Introduce steam for 150 seconds. By repeating this operation three times, Al ₂ O ₃ is introduced into the pattern forming film. Using this pattern as a mask, plasma treatment (100 sccm, 0.4 Pa, 200 W, 120 seconds) is performed with an ICP plasma etching apparatus (manufactured by Tokyo Electron Limited) using _{ethane hexafluoride (C 2} F _{6) and Ar gas to silicon.} Perform dry etching processing of the oxide film. Then, the cross section where the pattern of the silicon oxide film is formed before and after the plasma treatment is observed with a scanning electron microscope (SEM) JSM7800F (manufactured by JEOL Ltd.) at an acceleration voltage of 1.5 kV, an emission current of 37.0 μA, and a magnification of 100,000 times. Then, the thickness of the pattern-forming film into which the metal is introduced and the depth of processing into the silicon oxide film portion are measured, and the etching selectivity is calculated by the following formula.
Etching selectivity = Processing depth to silicon oxide film / (Thickness of pattern forming film before plasma treatment-Thickness of pattern forming film after plasma treatment)
The etching selectivity is preferably larger than 2.0, more preferably 2.5 or more, further preferably 3.0 or more, further preferably 5.0 or more, and 10.0 or more. Is particularly preferable. In the present specification, when the etching selectivity is within the above range, it can be determined that the etching processability when processing the pattern shape on the substrate is good. If the etching processability is good, it is generally possible to dig deep into the substrate.

In the present embodiment, the maximum metal content (atom%) when the metal is introduced into the pattern forming film is preferably 15 atom% or more, more preferably 20 atom% or more, and more preferably 25 atom% or more. It is more preferable to have. The maximum metal content (atom%) when a metal is introduced into the pattern forming film is calculated as follows. First, a copolymer solution sample is obtained by dissolving in PGMEA so that the polymer content is 3% by mass and p-toluenesulfonic acid is 0.3% by mass. Then, the copolymer solution sample is spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness is 300 nm, it is fired on a hot plate at 230 ° C. for 5 minutes to form a pattern-forming film. Next, the pattern-forming film was placed in an ALD (atomic layer deposition apparatus: SUNALE R-100B manufactured by PICUSAN), and TMA (trimethylaluminum, Al (CH ₃ ) ₃ ) gas was introduced at 95 ° C. for 300 seconds. Introduce steam for 150 seconds. By repeating this operation three times, Al ₂ O ₃ is introduced into the pattern forming film. The pattern-forming film after the introduction of Al ₂ O _{3 was} installed in an XPS device (Nexsa XPS System manufactured by Thermo Fisher Scientific), and the concentration profile of Al element in the film thickness direction was determined by XPS analysis (X-ray photoelectron spectroscopy analysis). obtain. The _{film thickness of the pattern forming film after the introduction of Al 2} O ₃ is formed by scratching the sample surface with tweezers to expose the surface of the silicon substrate, and the step portion is formed by a palpation type profilometer (stock company). Obtained by measuring with the company Kosaka Seisakusho model number: ET-4000). That is, the maximum metal content (atom%) is the metal content at the thickness in which the most metal is contained in the thickness direction of the pattern forming film.

The metals to be introduced into the pattern forming film include Li, Be, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga and Ge. , As, Rb, Sr, Y, Zr, Nb, Mo, Ru, Pd, Ag, Cd, In, Sn, Sb, Te, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt , Au, Hg, Tl, Pb, Bi, Po, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and the like. Above all, it is preferable to use Al, B, Si, Sn, Te, Zr, and W as the metal to be introduced into the pattern forming film.

In one embodiment, when the pattern-forming composition is applied onto a substrate to form a pattern-forming film having a thickness of 300 nm, and a metal gas is introduced into the pattern-forming film under a pressure of 500 Pa for 300 seconds, a pattern is formed. The total metal content in the forming film is 4.0 atom% or more, the maximum metal content in the thickness direction of the pattern forming film is Aatom%, and the metal content at the midpoint in the thickness direction of the pattern forming film. When is Batom%, the value of A / B is preferably 10.0 or less. As described above, the pattern-forming composition of the present embodiment may satisfy the above conditions in the total content of the metal introduced in the pattern-forming step and the metal distribution in the pattern-forming film.

When the pattern-forming composition of the present embodiment satisfies the above conditions, it is necessary to more effectively enhance the etching processability when processing the pattern shape on the substrate after forming the pattern-forming film from the pattern-forming composition. Can be done.

In the present embodiment, when the metal gas is introduced into the pattern forming film under a pressure of 500 Pa for 300 seconds, the total metal content (atom%) contained in the pattern forming film should be 4.0 atom% or more. It is preferable that the content is 4.5 atom% or more, and more preferably 5.0 atom% or more. The total content of the metal contained in the pattern forming film is preferably 60 atom% or less, and more preferably 50 atom% or less. The total metal content (atom%) is the content of the metal with respect to the total atomic weight in the pattern-forming film. The total content of the metal contained in the pattern-forming film can be adjusted by selecting the metal species or adjusting the structural units constituting the polymer. The total metal content (atom%) in the pattern-forming film is a value calculated from the depth profile (XPS measurement) of the Al content in the pattern-forming film, as will be described later. Specifically, the Al content at each depth in the pattern-forming film is plotted, an approximate curve is obtained by the nonlinear least squares method, and this is used as a depth profile. This profile is used to calculate the area of the film thickness range obtained by the stylus type step meter in the measurement of the maximum metal content (atom%) in the thickness direction of the pattern forming film described later from the integrated value. For simplicity, the profile printed on paper may be cut out and the total content may be calculated by weight comparison. At that time, the total content of 0% is set to 0 g by weight, and the total content of 100% is set so that the depth profiles are all 100%, and the weight of the printed and cut out product is used.

In the present embodiment, when a metal gas is introduced into the pattern forming film under a pressure of 500 Pa for 300 seconds, the maximum metal content in the thickness direction of the pattern forming film is set to Atom%, and the maximum metal content in the thickness direction of the pattern forming film is set to Atom%. When the metal content at the intermediate point is Batom%, the A / B value is preferably 10.0 or less, more preferably 9.0 or less, and 8.5 or less. The following is more preferable. Further, the A / B value is preferably 2 or less, and particularly preferably 1.5 or less. The A / B value can be adjusted by selecting the metal type or adjusting the constituent units constituting the polymer.

In the present embodiment, the fact that the A / B value is within the above range means that the metal infiltrates in the depth direction in the pattern forming film. Usually, when a metal gas is introduced into the pattern forming film, the surface of the pattern forming film contains the most metal. However, in the present embodiment, by appropriately controlling the structure of the polymer, the ratio of sugar derivatives, the length of sugar chains, the ratio of cross-linking groups, etc., the metal is used not only for the surface of the pattern-forming film but also for pattern-forming. It can also be distributed in the depth direction of the membrane. As a result, the strength of the pattern-forming film in the thickness direction can be increased, and a strong pattern-forming film is formed as a whole. As a result, it is possible to improve the etching processability when processing the pattern shape on the substrate after forming the pattern forming film on the substrate.

The maximum metal content (atom%) in the thickness direction of the pattern forming film is calculated as follows. First, a copolymer solution sample is obtained by dissolving in PGMEA so that the polymer content is 3% by mass and p-toluenesulfonic acid is 0.3% by mass. Then, the copolymer solution sample is spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness is 300 nm, it is fired on a hot plate at 230 ° C. for 5 minutes to form a pattern-forming film. Next, the pattern-forming film was placed in an ALD (atomic layer deposition apparatus: SUNALE R-100B manufactured by PICUSAN), and TMA (trimethylaluminum, Al (CH ₃ ) ₃ ) gas was introduced at 95 ° C. for 300 seconds. Introduce steam for 150 seconds. By repeating this operation three times, Al ₂ O ₃ is introduced into the pattern forming film. The pattern-forming film after the introduction of Al ₂ O _{3 was} installed in an XPS device (Nexsa XPS System manufactured by Thermo Fisher Scientific), and in XPS analysis (X-ray photoelectron spectroscopy analysis), sputtering using Ar ions and surface element concentration. The measurement and the film thickness measurement are repeated to obtain the concentration profile of the Al element in the film thickness direction. The concentration profile of the Al element is, for example, a profile as shown in FIG. The _{film thickness of the pattern forming film after the introduction of Al 2} O ₃ is a tactile profilometer (Kosaka Co., Ltd.) that measures the stepped portion formed between the element concentration measurement performed portion and the unsputtered portion formed at each sputtering time. It is obtained by measuring with the model number: ET-4000) manufactured by Seisakusho. Then, the maximum concentration of the obtained Al element in the obtained concentration profile of the Al element becomes the maximum metal content (atom%).

The maximum metal content (atom%) in the thickness direction of the pattern forming film is preferably 15 atom% or more, more preferably 17 atom% or more, further preferably 20 atom% or more, and 25 atom% or more. Is particularly preferable. Further, the maximum metal content (atom%) in the thickness direction of the pattern forming film is preferably 50 atom% or less. By setting the maximum metal content in the thickness direction of the pattern forming film within the above range, the etching processability when processing the pattern shape on the substrate can be more effectively enhanced.

The metal content (atom%) at the midpoint in the thickness direction of the pattern forming film is the Al element in the film thickness direction obtained when the maximum metal content (atom%) in the thickness direction of the pattern forming film was calculated. It can be calculated from the concentration profile of. It can be calculated by reading the metal content at the midpoint in the thickness direction of the pattern forming film from the concentration profile of the Al element in the film thickness direction.

The metal content (atom%) at the midpoint in the thickness direction of the pattern forming film is preferably 1.5 atom% or more, more preferably 5 atom% or more, and further preferably 15 atom% or more. , 25 atom% or more is particularly preferable. Further, the metal content (atom%) at the midpoint in the thickness direction of the pattern forming film is preferably 50 atom% or less. By setting the metal content at the midpoint in the thickness direction of the pattern forming film within the above range, the etching processability when processing the pattern shape on the substrate can be more effectively improved.

The pattern-forming composition of the present embodiment is preferably a pattern-forming mask material. That is, the pattern-forming film formed from the pattern-forming composition of the present embodiment preferably serves as a protective film when etching the substrate. The pattern-forming film formed from the pattern-forming composition of the present embodiment can also be expected to have an effect on the gas permeability required for the nanoimprint method. Such a pattern-forming film may be peeled off after the etching step.

Further, the pattern-forming composition of the present embodiment may be a pattern-forming self-organizing composition. In the present specification, self-assembly (Directed Self-Assembly) refers to a phenomenon in which an organization or structure is spontaneously constructed without being caused only by control from external factors. For example, by applying a self-assembled composition for pattern formation on a substrate and performing annealing or the like, a film having a phase-separated structure by self-assembly (self-assembled film) is formed, and the self-assembled film is formed. By removing some of the phases, a pattern can be formed on the substrate. Such a pattern shape serves as a protective film, and the substrate can be subjected to a desired etching process.

(polymer)
The pattern-forming composition of the present invention preferably contains a polymer, and the polymer preferably contains a unit derived from a sugar derivative. The sugar derivative may be a monosaccharide-derived sugar derivative or a structure in which a plurality of monosaccharide-derived sugar derivatives are bonded. Further, in the polymer containing a unit derived from a sugar derivative, the unit derived from the sugar derivative may be a structural unit having a sugar derivative-derived structure in the side chain, or a structural unit having a sugar derivative-derived structure in the main chain. There may be.

The unit derived from the sugar derivative is preferably at least one selected from the unit derived from the pentose derivative and the unit derived from the hexose derivative.
The pentose derivative is not particularly limited as long as it has a structure derived from pentose in which the hydroxyl group of the known monosaccharide or polysaccharide pentose is modified with at least a substituent. The pentose derivative is preferably at least one selected from hemicellulose derivatives, xylose derivatives and xylooligosaccharide derivatives, and more preferably at least one selected from hemicellulose derivatives and xylooligosaccharide derivatives.
The hexose derivative is not particularly limited as long as it has a structure derived from hexose in which the hydroxyl group of the hexose of a known monosaccharide or polysaccharide is modified with at least a substituent. The hexose derivative is preferably at least one selected from a glucose derivative and a cellulose derivative, and more preferably a cellulose derivative.
Among them, the unit derived from the sugar derivative is preferably at least one selected from the unit derived from the cellulose derivative, the unit derived from the hemicellulose derivative and the unit derived from the xylooligosaccharide derivative.

Among them, the unit derived from the sugar derivative preferably contains at least one selected from the structure represented by the following general formula (103) and the structure represented by the following general formula (104).

In the general formulas (103) and (104), R ¹ independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group, an acyl group, an aryl group, a trimethylsilyl group or a phosphoryl group, and a plurality of them. there R ¹ may be different even in the same. R ⁵ represents a hydrogen atom or an alkyl group. X ¹ and Y ¹ independently represent a single bond or a linking group, respectively. r represents an integer of 1 or more, * mark any oxygen atoms r is or represents any one of the binding sites of R ^1, or in place of R ¹ bonded to R ¹ in the case of two or more Represents the binding site with one.

In the general formulas (103) and (104), R ¹ independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group, an acyl group, an aryl group, a trimethylsilyl group or a phosphoryl group, respectively. A plurality of R ^1s may be the same or different. Above all, ^{it is preferable that R 1} is independently a hydrogen atom or an acyl group having 1 or more and 3 or less carbon atoms. The above alkyl group also includes a sugar chain. That is, the sugar chain portion in the general formulas (103) and (104) may further have a branched chain.

When R ¹ is an alkyl group or an acyl group, the number of carbon atoms thereof can be appropriately selected depending on the intended purpose. For example, the number of carbon atoms is preferably 2 or more, preferably 200 or less, more preferably 100 or less, further preferably 20 or less, and particularly preferably 4 or less.

Specific examples of R ¹ include, for example, an acetyl group, a propanoyl group, a butyryl group, an isobutyryl group, a valeryl group, an isovaleryl group, a pivaloyl group, a hexanoyl group, an octanoyl group, a chloroacetyl group, a trifluoroacetyl group, and a cyclopentanecarbonyl group. , Cyclohexanecarbonyl group, benzoyl group, methoxybenzoyl group, chlorobenzoyl group and other acyl groups; methyl group, ethyl group, propyl group, butyl group, t-butyl group and other alkyl groups and the like. Among these, an acetyl group, a propanoyl group, a butyryl group, and an isobutyryl group are preferable, and an acetyl group is particularly preferable.

In the general formulas (103) and (104), R ⁵ represents a hydrogen atom or an alkyl group. Among them, R ⁵ is preferably a hydrogen atom or an alkyl group having 1 or more and 3 or less carbon atoms, and particularly preferably a hydrogen atom or a methyl group.

In the general formulas (103) and (104), X ¹ and Y ¹ independently represent a single bond or a linking group, respectively.
When X ¹ is a linking group, the X ^1, an alkylene group, -O -, - NH 2 - , but include groups containing a carbonyl group, or X ¹ is a single bond, or carbon atoms It is preferably an alkylene group having 1 or more and 6 or less, and more preferably an alkylene group having 1 or more and 3 or less carbon atoms.
When Y ¹ is a linking group, ^{examples of Y 1} include a group containing an alkylene group, a phenylene group, -O-, -C (= O) O-, and the like. Y ¹ may be a linking group in which these groups are combined. Among them, Y ¹ is preferably a linking group represented by the following structural formula.

In the above structural formula, * mark represents the binding site with the main chain side, and * mark represents the binding site with the sugar unit of the side chain.

In the general formulas (103) and (104), r represents an integer of 1 or more, and may be 2 or more or 3 or more. Further, r is preferably 1500 or less, more preferably 1200 or less, further preferably 500 or less, further preferably 100 or less, and particularly preferably 50 or less. Most preferably, it is 10 or less.

The average degree of polymerization of the sugar unit is the same as the preferable range of r above. The average degree of polymerization of sugar units is the number of sugar units forming one sugar part, and when the sugar part has a side chain structure, the number of sugar units constituting the side chain is also included in the average degree of polymerization. Is done. The average degree of polymerization of the above sugar units can be calculated by the following measuring method.
First, the solution containing the sugar derivative is kept at 50 ° C. and centrifuged at 15,000 rpm for 15 minutes to remove insoluble matter. Then, the total sugar amount and the reducing sugar amount (both in terms of xylose) of the supernatant are measured. Then, the average degree of polymerization is calculated by dividing the total amount of sugar by the amount of reducing sugar. If the above measurement method cannot be adopted, gel permeation chromatography, size exclusion chromatography, light scattering method, viscosity method, terminal group quantification method, sedimentation velocity method, MULDI-TOF-MS method, structural analysis method by NMR, etc. May be adopted.
When measuring the average degree of polymerization of sugar units after copolymer synthesis, ¹ H-NMR is used to show the integral value of the peak derived from the sugar chain (around 3.3-5.5 ppm) and the peak derived from other components of the sugar derivative. The integral value is calculated, and the average degree of polymerization is calculated from the ratio of each integral value. ^{When R 1} in the general formulas (103) and (104) is not a hydrogen atom, the integrated value of the peak derived from ^{-OR 1} can be used instead of the peak derived from the sugar chain (however, in this case). -OR ¹ R ¹ is not a sugar chain).

* Mark in the general formula (103) and (104), an oxygen atom which r is any representative of any one of the binding sites of ^{R 1,} or in place of ^{R 1} bonded to ^{R 1} in the case of two or more Represents a binding site with any one of. That is, the polymerization site of the sugar unit in the general formulas (103) and (104) may be ^{either R 1} in the sugar unit or the ^{oxygen atom to which R 1} is bonded, and any one of the polymerization sites is the polymerization site. Is preferable. When R ¹ is an alkyl group having a substituent, R ¹ may be a sugar chain, so that there is only one binding site marked with * in the general formulas (103) and (104). However, in reality, the sugar chain may have a side chain consisting of additional sugar chains.

The unit derived from the sugar derivative includes at least one selected from the structure represented by the general formula (103) and the structure represented by the general formula (104), and is represented by the general formula (103). It is preferable that the structure is mainly contained. It is considered that this is because the structure represented by the general formula (103) is more compact than the structure represented by the general formula (104), and the free volume radius of the polymer can be easily controlled.

The polymer contained in the pattern-forming composition is preferably a copolymer. The copolymer may be a block copolymer, but is preferably a random copolymer. By using a random copolymer, a more homogeneous pattern-forming film can be formed.

When the polymer contained in the pattern-forming composition is a copolymer, the polymer preferably has a structure represented by the following general formula (105).

In the general formula (105), W ¹ represents a carbon atom or a silicon atom. Above all, W ¹ is preferably a carbon atom. Further, in the general formula (105), W ² represents -CR _2- , -O-, -S- or -SiR _2- (where R is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Represented, a plurality of Rs may be the same or different). Among them, W ² is _{preferably -CR 2-} , and more preferably _{-CH 2-.}

In the general formula (105), R ¹¹ represents a hydrogen atom, an alkyl group having 1 or more and 3 or less carbon atoms, or a hydroxyl group. Alkyl group having 1 to 3 carbon atoms, preferably a methyl group, R ¹¹ is more preferably a hydrogen atom or a methyl group, more preferably a hydrogen atom.

In the general formula (105), R ¹² represents a hydrogen atom, a hydroxyl group, an acetyl group, a methoxycarbonyl group, an aryl group, an allyl group, a glycidyl ether group, a glycidyl ester group, an isocyanate ester group or a pyridyl group. The allyl group is _{preferably a group represented by -R 3} -CH = CH ₂ , and the glycidyl ether group is preferably a group represented by -CH ₂ -OR ₃ -epoxy, and a glycidyl ester. The group is _{preferably a group represented by -COO-R 3} -epoxy, and the isocyanate ester group is preferably a group represented by -COO-R _3- NCO. Here, R ₃ is an alkylene group which may have a substituent. Examples of the alkylene group which may have a substituent include -CH ₂ -,-(CH ₂ ) ₂ -,-(CH ₂ ) ₃ -,-(CH ₂ ) ₄ -,-(CH ₂ ) ₅ -, -CH ₂ OCH ₂ -,-(CH ₂ ) ₂ OCH ₂ -,-(CH ₂ ) ₃ OCH ₂ -,-(CH ₂ ) ₄ OCH ₂ -,-(CH ₂ ) ₅ OCH ₂ -etc. Can be mentioned. Further, the alkylene group which may have a substituent may be a cycloalkylene group or a crosslinked cyclic cycloalkylene group.

Among them, R ¹² is preferably a methoxycarbonyl group, an aryl group, a glycidyl ether group, a glycidyl ester group or a pyridyl group, more preferably a glycidyl ester group or an aryl group, and a glycidyl ester group or a phenyl group. Is even more preferable. It is also preferable that the phenyl group is a phenyl group having a substituent. Examples of the phenyl group having a substituent include a 4-t-butylphenyl group, a methoxyphenyl group, a dimethoxyphenyl group, a trimethoxyphenyl group, a trimethylsilylphenyl group, a tetramethyldisilylphenyl group and the like. It ^{is also preferable that R 12} is a naphthalene group.

As described above, R ¹² is preferably a phenyl group, and in this case, the unit derived from the structure represented by the general formula (105) is a unit derived from a styrene compound. Examples of the styrene compound include styrene, o-methylstyrene, p-methylstyrene, ethylstyrene, p-methoxystyrene, p-phenylstyrene, 2,4-dimethylstyrene, pn-octylstyrene, and pn-. Examples thereof include decylstyrene, pn-dodecylstyrene, chlorostyrene, bromostyrene, trimethylsilylstyrene, hydroxystyrene, 3,4,5-methoxystyrene, pentamethyldisilylstyrene and the like. Among them, the styrene compound is preferably at least one selected from styrene and trimethylsilyl styrene, and more preferably styrene.

It ^{is also preferable that R 12} is a glycidyl ester group. In this case, the unit derived from the structure represented by the general formula (105) is a unit derived from the glycidyl acrylate compound. Examples of the glycidyl acrylate compound include glycidyl acrylate, glycidyl methacrylate, 4-hydroxybutyl acrylate glycidyl ether, oxylan-2-ylmethyl-2-ethylidene pentanoete and the like. Among them, the glycidyl acrylate compound is preferably at least one selected from glycidyl methacrylate and 4-hydroxybutyl acrylate glycidyl ether.

The weight average molecular weight (Mw) of the polymer is preferably 500 or more, more preferably 1000 or more, and further preferably 1500 or more. The weight average molecular weight (Mw) of the polymer is preferably 1 million or less, more preferably 500,000 or less, further preferably 300,000 or less, and even more preferably 250,000 or less. .. The weight average molecular weight (Mw) of the polymer is a value measured by GPC in terms of polystyrene.

The ratio (Mw / Mn) of the weight average molecular weight (Mw) of the polymer to the number average molecular weight (Mn) is preferably 1 or more. Further, Mw / Mn is preferably 2 or less, more preferably 1.5 or less, and further preferably 1.3 or less. By setting Mw / Mn within the above range, the pattern-forming composition of the present embodiment can form a fine and good pattern structure with higher accuracy.

As described above, the polymer contains a unit derived from a sugar derivative, and the content of the unit derived from the sugar derivative in the polymer is preferably 60% by mass or more, more preferably 65% by mass or more, 70. It is more preferably mass% or more. The content of the unit derived from the sugar derivative in the polymer is preferably 90% by mass or less, and more preferably 85% by mass or less. By setting the content of the unit derived from the sugar derivative in the polymer within the above range, the solubility in an organic solvent can be increased.

Further, the content of the unit represented by the general formula (105) in the polymer may be 5% by mass or more or 10% by mass or more with respect to the total mass of the polymer. Further, the content of the unit represented by the general formula (105) in the polymer is preferably 40% by mass or less, and more preferably 30% by mass or less. The content of the unit represented by the general formula (105) in the polymer can be calculated by ^{1 1 H-NMR.}

The polymer may have other structural units in addition to the above-mentioned structural units. Examples of other structural units include lactic acid-derived units, siloxane bond-containing units, amide bond-containing units, urea bond-containing units, and the like.

(Polymer synthesis method)
The polymer can be synthesized by a known polymerization method such as living radical polymerization, living anionic polymerization, or atom transfer radical polymerization. For example, in the case of living radical polymerization, a polymer can be obtained by reacting with a monomer using a polymerization initiator such as AIBN (α, α'-azobisisobutyronitrile). In the case of living anionic polymerization, a polymer can be obtained by reacting butyllithium with a monomer in the presence of lithium chloride.

The sugar portion of the sugar derivative as described above may be obtained by synthesis, but may be obtained by combining the steps of extracting from lignocellulose derived from woody plants or herbaceous plants. When a method of extracting from a woody plant, a lignocellulose derived from a herbaceous plant, or the like is adopted in order to obtain a sugar portion, the extraction method described in JP-A-2012-100546 or the like can be used. Xylan can be extracted by, for example, the method disclosed in Japanese Patent Application Laid-Open No. 2012-180424. Further, cellulose can be extracted by, for example, the method disclosed in Japanese Patent Application Laid-Open No. 2014-148629.

When obtaining a sugar derivative, it is preferable to modify the OH group of the sugar portion using the above extraction method by acetylation or halogenation. For example, when an acetyl group is introduced, an acetylated sugar derivative can be obtained by reacting with acetic anhydride.

The compound having the structure represented by the general formula (105) may be formed by synthesis, or a commercially available product may be used. When synthesizing a compound having a structure represented by the general formula (105), a known synthesis method can be adopted. When using a commercially available product, for example, Amino-terminated PS (Mw = 12300Da, Mw / Mn = 1.02, manufactured by Polymer Source Co., Ltd.), allyl glycidyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.), glycidyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), glycidyl acrylate (Tokyo Chemical Industry Co., Ltd.) (Manufactured by Kogyo Co., Ltd.), Glycidyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.), 4-Hydroxybutyl acrylate glycidyl ether (manufactured by Mitsubishi Chemical Co., Ltd.), Oxylan-2-ylmethyl-2-ethylidene pentanoete (manufactured by Achemica), 3,4 -Epoxycyclohexylmethylmethacrylate (manufactured by Daicel) or the like can be used.

Copolymers are available from Macromolecules Vol. 36, No. It can be synthesized with reference to 6, 2003. Specifically, a sugar derivative and a compound having a structure represented by the general formula (105) are put in a solvent containing DMF, water, acetonitrile and the like, and a reducing agent is added. Examples of the reducing agent include NaCNBH _{3 and the} like. Then, the mixture is stirred at 30 ° C. or higher and 100 ° C. or lower for 1 day or more and 20 days or less, and a reducing agent is appropriately added as necessary. A precipitate can be obtained by adding water, and a copolymer can be obtained by vacuum drying the solid content.

Examples of the method for synthesizing the copolymer include a synthesis method using radical polymerization, RAFT polymerization, ATRP polymerization, click reaction, and NMP polymerization, in addition to the above methods.
Radical polymerization is a polymerization reaction that occurs when an initiator is added to generate two free radicals by a thermal reaction or a photoreaction. The monomer (eg, a styrene monomer and a sugar methacrylate compound in which methacrylic acid is added to the β-1 position at the end of the xylooligosaccharide) and the initiator (for example, an azo compound such as azobisisobutyronitrile (AIBN)) are heated at 150 ° C. This makes it possible to synthesize a polystyrene-polysaccharide methacrylate random copolymer.
RAFT polymerization is a radical-initiated polymerization reaction involving an exchange chain reaction using a thiocarbonylthio group. For example, a method can be taken in which the OH group attached to the terminal 1 position of the xylooligosaccharide is converted into a thiocarbonylthio group, and then the styrene monomer is reacted at 30 ° C. or higher and 100 ° C. or lower to synthesize a copolymer (Material Maters vol). .5, No.1 Latest Polymer Synthesis Sigma Aldrich Japan Co., Ltd.).
ATRP polymerization, the terminal OH group of the sugar halogenated metal complex _{[(CuCl, CuCl 2, CuBr} , CuBr 2 or CuI, etc.) + TPMA (tris (2- pyridylmethyl) amine)], MeTREN (tris [2- (dimethylamino ) Ethyl] amine), etc.), a monomer (eg, styrene monomer), and a polymerization initiator (2,2,5-trimethyl-3- (1-phenylethoxy) -4-phenyl-3-azahexane). Allows the synthesis of sugar copolymers (eg, sugar-styrene block copolymers).
In NMP polymerization, by heating with an alkoxyamine derivative as an initiator, a reaction with a monomer molecule is caused to generate nitroxide. After that, radicals are generated by thermal dissociation, and the polymerization reaction proceeds. Such NMP polymerization is a kind of living radical polymerization reaction. A monomer (for example, a styrene monomer and a sugar methacrylate compound in which methacrylic acid is added to the β-1 position at the end of a xylooligosaccharide) is mixed, and 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) is used as an initiator. A polystyrene-polysaccharide methacrylate random copolymer can be synthesized by heating at 140 ° C.
The click reaction is a 1,3-bipolar azide / alkyne cycloaddition reaction using a sugar having a propargyl group and a Cu catalyst.

(Manufacturing method of composition for pattern formation)
In the method for producing a pattern-forming composition, it is preferable to mix the above-mentioned polymer and solvent. The solvent is preferably an organic solvent, and examples of the organic solvent include alcohol-based solvents, ether-based solvents, ketone-based solvents, sulfur-containing solvents, amide-based solvents, ester-based solvents, hydrocarbon-based solvents, and the like. Be done. These solvents may be used alone or in combination of two or more.

Examples of alcohol-based solvents include methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, sec-butanol, tert-butanol, n-pentanol, i-pentanol, and 2-methylbutanol. , Se-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethyl Hexanol, sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec-tetradecyl alcohol, sec-heptadecyl alcohol, furfuryl alcohol , Phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol, etc .; ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanol Diol, 2-methyl-2,4-pentandiol, 2,5-hexanediol, 2,4-heptandiol, 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene Glycols, 1H, 1H-trifluoroethanol, 1H, 1H-pentafluoropropanol, 6- (perfluoroethyl) hexanol, etc .; can be mentioned.

Further, as the polyhydric alcohol partially ether-based solvent, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2. -Ethylbutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, diethylene glycol dimethyl ether, diethylene glycol ethylmethyl ether, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene Examples thereof include glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monopropyl ether.

Examples of the ether solvent include diethyl ether, dipropyl ether, dibutyl ether, diphenyl ether, tetrahydrofuran (THF) and the like.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-i-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone and methyl-n. -Hexyl ketone, di-i-butyl ketone, trimethylnonanone, cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, methylcyclohexanone, 2,4-pentandione, acetonylacetone, acetophenone, furfural and the like can be mentioned.

Examples of the sulfur-containing solvent include dimethyl sulfoxide and the like.

Examples of the amide solvent include N, N'-dimethylimidazolidinone, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide. , N-methylpropionamide, N-methylpyrrolidone and the like.

Examples of the ester solvent include diethyl carbonate, propylene carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate and acetic acid. sec-butyl, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, acet Methyl acetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl acetate ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate (PGMEA), propylene acetate Glycol monoethyl ether, propylene glycol monopropyl ether acetate, propylene glycol monobutyl acetate ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl acetate ether, glycol diacetate, methoxytriglycol acetate, ethyl propionate, n-propionic acid Butyl, i-amyl propionate, methyl 3-methoxypropionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate , Diethyl phthalate and the like.

As the hydrocarbon solvent, for example, as an aliphatic hydrocarbon solvent, n-pentane, i-pentane, n-hexane, i-hexane, n-heptane, i-heptane, 2,2,4-trimethylpentane, n-octane, i-octane, cyclohexane, methylcyclohexane, etc .; as aromatic hydrocarbon solvents, benzene, toluene, xylene, mesitylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, i-propylbenzene, diethylbenzene, etc. Examples thereof include i-butylbenzene, triethylbenzene, di-i-propylbenzene, n-amylnaphthalene and anisole.

Among these, propylene glycol monomethyl ether acetate (PGMEA), N, N-dimethylformamide (DMF), propylene glycol monomethyl ether (PGME), anisole, ethanol, methanol, acetone, methyl ethyl ketone, hexane, tetrahydrofuran (THF), dimethyl sulfoxide. (DMSO), 1H, 1H-trifluoroethanol, 1H, 1H-pentafluoropropanol, 6- (perfluoroethyl) hexanol, ethyl acetate, propyl acetate, butyl acetate, cyclohexanone, furfural are more preferred, and PGMEA or DMF is further preferred. Preferably, PGMEA is even more preferred. These solvents may be used alone or in combination of two or more.

The content of the polymer in the pattern-forming composition is preferably 0.1% by mass or more, more preferably 1% by mass or more, based on the total mass of the pattern-forming composition. The polymer content is preferably 30% by mass or less with respect to the total mass of the pattern-forming composition.

<Arbitrary ingredient>
When producing the pattern-forming composition, an ionic liquid may be further blended as an optional component. An ionic liquid is a solvent that is liquid at 100 ° C. or lower and is composed only of ions. At least one of the cation part and the anion part of the ion constituting the ionic liquid is composed of organic ions.

Since the pattern-forming composition contains an ionic liquid, the compatibility between the polymer and the organic solvent can be enhanced. The ionic liquid also has a function of promoting phase separation of the block copolymer.

The ionic liquid is composed of a cation part and an anion part, and the cation part of the ionic liquid is not particularly limited, and one generally used for the cation part of the ionic liquid can be used. Preferred examples of the cation portion of the ionic liquid include nitrogen-containing aromatic ions, ammonium ions, and phosphonium ions.

Examples of the nitrogen-containing aromatic cation include pyridinium ion, pyridadinium ion, pyrimidinium ion, pyrazinium ion, imidazolium ion, pyrazonium ion, oxazolium ion, 1,2,3-triazolium ion, 1, Examples thereof include 2,4-triazolium ion, thiazolium ion, piperidinium ion and pyroridinium ion.

Examples of the anion portion of the ionic liquid include halogen ion, carboxylate ion, phosphinate ion, phosphate ion, phosphonate ion, bis (trifluoromethylsulfonyl) imide ion and the like, and bis (trifluoromethylsulfonyl) imide ion is preferable. Examples of the halogen ion include chloride ion, bromide ion, and iodide ion, and chloride ion is preferable. Examples of the carboxylate ion include formate ion, acetate ion, propionate ion, butyrate ion, hexanoate ion, maleate ion, fumarate ion, oxalate ion, rectate ion, and pyruvate ion. , Format ion, acetate ion, propionate ion are preferable.

The pattern-forming composition may contain, for example, a surfactant or the like as an optional component. When the pattern-forming composition contains a surfactant, the coatability of pattern-forming to a substrate or the like can be improved. Preferred surfactants include nonionic surfactants, fluorine-based surfactants and silicone-based surfactants. These may be used alone or in combination of two or more.

Further, the pattern-forming composition may further contain a catalyst as an optional component. Examples of the catalyst include acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium-p-toluenesulfonic acid, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, ammonium dodecylbenzenesulfonic acid, and hydroxybenzoic acid. Examples of the curing agent include ethylenediamine, diethylenetriamine, triethylenetetramine, diethylaminopropylamine, dimethylaminopropylamine, m-xylenediamine, m-phenylenediamine, triethylamine, benzyldimethylamine and the like.

The pattern-forming composition of the present embodiment may contain a monomer component constituting the polymer. For example, various monomers constituting the polymer can be appropriately added in order to improve the desired properties.

(Pattern formation method)
The present invention is a step of applying the above-mentioned pattern-forming composition containing a polymer onto a substrate to form a pattern-forming film, and a step of introducing a metal into at least a part of the pattern-forming film for metal-containing pattern formation. Once the film is obtained, it is also related to a pattern forming method including. Here, when the free volume radius of the polymer is Pr and the nuclear radius of the metal is Mr, the condition of 2 ≦ Pr / Mr ≦ 3.3 is satisfied. According to the pattern forming method of the present invention, it is possible to improve the etching processability when processing the pattern shape on the substrate after forming the pattern forming film from the pattern forming composition.

Further, the total content of the metal contained in the metal-containing pattern forming film is 4.0 atom% or more, the maximum metal content in the thickness direction of the metal-containing pattern forming film is Aatom%, and the thickness of the pattern forming film is set to Aatom%. When the metal content at the midpoint in the direction is Batom%, the A / B value is preferably 10.0 or less. That is, the step of obtaining the metal-containing pattern forming film is a step of introducing the metal so that the total content of the metal contained in the metal-containing pattern forming film and the A / B value satisfy the above conditions. preferable. By setting the step of obtaining the metal-containing pattern forming film as the above conditions, the etching processability when processing the pattern shape on the substrate after forming the pattern forming film from the pattern forming composition can be more effectively enhanced. Can be done.

Examples of the substrate used in the pattern forming method of the present embodiment include substrates such as glass, silicon, SiN, GaN, and AlN. Further, a substrate made of an organic material such as PET, PE, PEO, PS, cycloolefin polymer, polylactic acid, and cellulose nanofiber may be used. Further, a plurality of layers made of different materials may be sandwiched between the substrate and the guide pattern forming layer. The material is not particularly specified, but is, for example _{, an inorganic material such as SiO 2} , SiN, Al ₂ O ₃ , AlN, GaN, GaAs, W, SOC, SOG, or a commercially available adhesive. Organic materials can be mentioned.

The method of applying the pattern-forming composition on the substrate to form the pattern-forming film is not particularly limited, and examples thereof include a method of applying the pattern-forming composition to be used by a spin coating method or the like. Be done.

The pattern forming method of the present embodiment preferably further includes a step of forming a pattern on the pattern forming film after the step of forming the pattern forming film. In the step of forming the pattern, first, as shown in FIG. 2A, the pattern forming film 20 is formed by applying the pattern forming composition on the substrate 10. Then, as shown in FIG. 2B, at least a part of the pattern forming film 20 is removed so as to have a pattern shape desired to be formed on the substrate 10. For example, by laminating a resist film on the pattern forming film 20 and performing exposure and development processing, a pattern shape as shown in FIG. 2B can be formed.

Examples of the method for removing a part of the pattern forming film include reactive ion etching (RIE) such as chemical dry etching and chemical wet etching (wet development), spatter etching, and physical etching such as ion beam etching. Known methods can be mentioned. Removal of the pattern forming film is, for example, tetrafluoromethane, perfluorocyclobutane _(C _{4 F} 8), perfluoropropane _(C _{3 F} 8), perfluoroethane _(C _{2 F} 6), boron trichloride, trifluoroethylene It can be performed by dry etching with gases such as methane dioxide, trifluoromethane, carbon monoxide, argon, oxygen, nitrogen, chlorine, helium, sulfur hexafluoride, difluoromethane, nitrogen trifluoride and chlorine trifluoride. preferable.

Further, a chemical wet etching step can be adopted as a step of removing a part of the pattern forming film. Wet etching methods include, for example, a method of reacting with acetic acid for treatment, a method of reacting with a mixed solution of alcohol and water such as ethanol and i-propanol, and a method of treating with acetic acid or alcohol after irradiating with UV light or EB light. The processing method and the like can be mentioned.

A pattern can be formed on the pattern forming film as described above. The pattern to be formed is preferably a line-and-space pattern, a hole pattern, or a pillar pattern.

The pattern forming method of the present embodiment includes a step of introducing a metal into at least a part of the pattern forming film to obtain a metal-containing pattern forming film. The step of obtaining the metal-containing pattern forming film (metal introduction step) is preferably provided after the pattern shape is formed on the pattern forming film, but the metal introduction is performed before the pattern shape is formed on the pattern forming film. A process may be provided. Metals introduced into the pattern forming film include Li, Be, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Nb, Mo, Ru, Pd, Ag, Cd, In, Sn, Sb, Te, Cs, Ba, La, Hf, Ta, W, Re, Os, Ir, Examples thereof include Pt, Au, Hg, Tl, Pb, Bi, Po, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The step of introducing the metal into the pattern-forming film can be carried out by, for example, the method described in Journal of Photopolymer Science and Technology Volume 29, Number 5 (2016) 653-657. When introducing a metal into the pattern-forming film, a method using a metal complex gas, a method of applying a solution containing the metal, or a method of introducing the metal into the resist by an ion implant method can be adopted. it can. Above all, in the step of obtaining the metal-containing pattern forming film (metal introduction step), it is preferable to adopt a method of spraying the metal complex gas on the pattern forming film.

In the step of obtaining the metal-containing pattern forming film, it is preferable that the metal is introduced so that the total content of the metal contained in the metal-containing pattern forming film is 4.0 atom% or more, and more preferably 4.5 atom. The metal is introduced so as to be% or more, more preferably 5.0 atom% or more. The upper limit of the total content of the metal contained in the metal-containing pattern forming film is preferably 60 atom% or less, and more preferably 50 atom% or less. Then, in the step of obtaining the metal-containing pattern-forming film, it is preferable that the metal of the pattern-forming film is introduced so that the A / B value is 10.0 or less. Here, A is the maximum metal content (atom%) in the thickness direction of the metal-containing pattern forming film, and B is the metal content (atom%) at the midpoint in the thickness direction of the pattern forming film. ..

In the step of obtaining the metal-containing pattern forming film, the metal gas is sprayed on the pattern forming film, and the spray pressure of the metal gas at this time is preferably 10 Pa or more, more preferably 50 Pa or more. It is more preferably 100 Pa or more. The spray pressure of the metal gas is preferably 700 Pa or less, more preferably 650 Pa or less, and even more preferably 600 Pa or less. The spraying time of the metal gas is preferably 5 seconds or longer, more preferably 15 seconds or longer, and even more preferably 30 seconds or longer. The spraying time of the metal gas is preferably 1800 seconds or less, more preferably 1200 seconds or less, and further preferably 900 seconds or less. In the step of obtaining the metal-containing pattern-forming film, for example, when the metal gas is sprayed on the pattern-forming film for 300 seconds under a pressure of 500 Pa, the total amount of metal contained in the metal-containing pattern-forming film is total. It is preferable that the content is 4.0 atom% or more and the A / B value is 10.0 or less.

It is preferable that an etching step is further provided after the metal is introduced into at least a part of the pattern forming film to obtain the metal-containing pattern forming film. As shown in FIG. 2C, this etching step is a step of etching a substrate using a patterned pattern-forming film as a protective film (mask).

Known methods for processing the substrate in the etching step include, for example, reactive ion etching (RIE) such as chemical dry etching and chemical wet etching (wet development), and physical etching such as spatter etching and ion beam etching. Can be mentioned. Processing of the substrate, for example, tetrafluoromethane, perfluorocyclobutane _(C _{4 F} 8), perfluoropropane _(C _{3 F} 8), trifluoromethane, carbon monoxide, argon, oxygen, nitrogen, chlorine, sulfur hexafluoride , Difluoromethane, nitrogen trifluoride, chlorine trifluoride and other gases are preferably used for dry etching.

In addition, a chemical wet etching process can be adopted in the etching process. Wet etching methods include, for example, a method of reacting with acetic acid for treatment, a method of reacting with a mixed solution of alcohol and water such as ethanol and i-propanol, and a method of treating with acetic acid or alcohol after irradiating with UV light or EB light. The processing method and the like can be mentioned.

The features of the present invention will be described in more detail below with reference to Examples and Comparative Examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention should not be construed in a limited manner by the specific examples shown below.

(Example 1)
[Synthesis of copolymer 1]
(Synthesis of Acetyl Sugar Methacrylate 1)
20 g of xylose was added to a mixed solution of 250 g of acetic anhydride and 320 g of acetic acid, and the mixture was stirred at 30 ° C. for 2 hours. Approximately 5 times the amount of cold water of the solution was added slowly with stirring, and after stirring for 2 hours, the mixture was allowed to stand overnight. To a solution prepared by adding 1.2 g of ethylenediamine and 01.4 g of acetic acid to 400 mL of THF in a flask and bringing the temperature to 0 ° C., 10 g of precipitated crystals was added, and the mixture was stirred for 4 hours. This was injected into 1 L of cold water and extracted twice with dichloromethane. 20 g of this extract, 300 mL of dichloromethane and 4.8 g of triethylamine were placed in a flask and cooled to −30 ° C. 2.8 g of methacryloyl chloride was added and the mixture was stirred for 2 hours. This was injected into 300 mL of cold water, extracted twice with dichloromethane, and the solvent was concentrated to obtain 16.1 g of acetylxylose methacrylate 1. The structure of the obtained acetylxylose methacrylate 1 is as follows.

(Synthesis of Acetylxylose Methacrylate-Styrene-Glysidyl Methacrylate Random Copolymer)
12.0 g of acetyl sugar methacrylate, 2.6 g of styrene (manufactured by Tokyo Kasei Co., Ltd.), 2.6 g of glycidyl methacrylate (manufactured by Tokyo Kasei Co., Ltd.), 100 g of THF as a solvent, and 0.8 g of azobisisobutyronitrile as a polymerization initiator in a flask. After the introduction, the glass container was sealed, the temperature was raised to 78 ° C. under a nitrogen atmosphere substituted with nitrogen, and the mixture was stirred for 6.0 hours. Then, the temperature was returned to room temperature, the inside of the glass container was placed under the atmosphere, and the solution was added dropwise to 300 g of methanol to precipitate a polymer. Then, the solution containing the precipitated polymer was suction-filtered to obtain 112 g of a white copolymer. The obtained copolymer 1 contains the following structural units.

[Preparation of solution sample]
The copolymer was dissolved in PGMEA so as to have 13% by mass of the copolymer and 0.3% by mass of the p-toluenesulfonic acid of the polymerization catalyst to obtain a copolymer solution sample.

(Example 2)
[Synthesis of copolymer 2]
(Synthesis of Acetylxylose Methacrylate-Styrene-Glysidyl Methacrylate Random Copolymer)
In the synthesis of the copolymer 1, the same method as in Example 1 except that the amount of styrene added was changed from 2.6 g to 2.3 g and the amount of glycidyl methacrylate added was changed from 2.6 g to 0.8 g. 12.0 g of copolymer 2 was obtained. Moreover, the copolymer solution sample was obtained in the same manner as in Example 1.

(Example 3)
[Synthesis of copolymer 3]
(Synthesis of Acetylxylose Methacrylate-Styrene Random Copolymer)
In the synthesis of the copolymer 1, 12.0 g of the copolymer 3 was obtained by the same method as in Example 1 except that the amount of styrene added was changed from 2.6 g to 2.1 g and glycidyl methacrylate was not added. Moreover, the copolymer solution sample was obtained in the same manner as in Example 1.

(Example 4)
[Synthesis of copolymer 4]
(Synthesis of Acetyl Xylotriose Methacrylate-Styrene Random Copolymer)
In the synthesis of the copolymer 1, 12.1 g of the copolymer 4 was obtained by the same method as in Example 1 except that xylose was changed to xylotriose. Moreover, the copolymer solution sample was obtained in the same manner as in Example 1. The obtained copolymer 4 contains the following structural units.

[Analysis of copolymer]
(Unit (l): Unit (m): Unit (n) ratio)
¹ The ratio (mass ratio) of the unit (l) and the unit (m): the unit (n) constituting the copolymer was obtained and calculated by 1 H-NMR, and the results are shown in Table 1. Specifically, 10 mg of the copolymers obtained in Examples and Comparative Examples were weighed and dissolved in 1 mL of deuterated chloroform to prepare a solution for NMR, and the obtained solution was transferred to an NMR sample tube (Kanto Chemical Co., Ltd.) and FT-. ¹ H-NMR measurement was performed by NMR (JNM-ECZ600R: JEOL Ltd.).

[Evaluation of free volume radius]
The copolymer solution samples obtained in Examples and Comparative Examples were spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness was 500 nm, it was fired on a hot plate at 230 ° C. for 5 minutes to form a pattern-forming film.
The pattern-forming film thus formed was further cut into a 15 mm × 15 mm square and installed in a small positron beam generator PALS-200A (thin film compatible positron annihilation life measuring device) manufactured by Fuji Invac. Using 22Na based positron beam as positron source, using BaF ₂ made scintillator and a photomultiplier tube as a γ-ray detectors to measure the positron annihilation lifetime under the following conditions.
Device constants: 263 to 272 ps, 24.55 ps / ch
Beam intensity: 1.5 keV
Measurement depth: 0 to 25 μm (estimated)
Measurement temperature: Room temperature Measurement atmosphere: Vacuum Total number of counts: Approximately 5,000,000 counts Sample pretreatment: Vacuum degassing at room temperature The positron annihilation lifetime curve obtained above was analyzed by the nonlinear least squares program POSITRONFIT, and the average free volume radius was calculated. .. The results are shown in Table 1.

[Measurement of Al content]
The copolymer solution samples obtained in Examples and Comparative Examples were spin-coated on a 2-inch silicon wafer substrate. After coating so that the film thickness was 300 nm, it was fired on a hot plate at 230 ° C. for 5 minutes to form a pattern-forming film.
The pattern-forming film thus formed was placed in an ALD (atomic layer deposition apparatus: SUNALE R-100B manufactured by PICUSAN), and TMA (trimethylaluminum, Al (CH ₃ ) ₃ ) gas was added at 95 ° C. for 300 seconds. After the introduction, steam was introduced for 150 seconds. By repeating this operation three times, Al ₂ O ₃ was introduced into the pattern-forming film.
The copolymer film-forming sample after the introduction of Al ₂ O ₃ was placed in an XPS device (Nexsa XPS System manufactured by Thermo Fisher Scientific), and surface elements were subjected to sputtering using Ar ions and XPS analysis (X-ray photoelectron spectroscopy). The concentration measurement and the film thickness measurement were sequentially repeated to obtain a concentration profile of the Al element (nuclear radius 0.118 nm) in the film thickness direction. For the _{film thickness of the pattern forming film after the introduction of Al 2} O _3, the step portion generated in the element concentration measurement part and the unsputtered part is measured for each sputtering time by a tactile profilometer (manufactured by Kosaka Seisakusho Co., Ltd. model number: It was obtained by measuring with ET-4000).
The "Al content in the film" shown in Table 2 is calculated from the obtained depth profile and corresponds to the total measurement of the Al element content in the film.
The "maximum Al content" shown in Table 2 is the Al element content at the point where the Al element concentration in the film in each profile is maximum.
The “Al content at 1/2 of the total film thickness” shown in Table 2 is the Al element content at the intermediate point of the film thickness of each profile.
The "A / B ratio" shown in Table 2 is the ratio of the Al element content calculated by the following formula.
A / B ratio = maximum Al element content / Al content at 1/2 of the total film thickness

[Preparation of sample for etching selectivity measurement]
The copolymer solution samples obtained in Examples and Comparative Examples were spin-coated on a 2-inch silicon wafer substrate with a silicon oxide film (thickness 2 um). After coating so that the film thickness was 300 nm, it was fired on a hot plate at 230 ° C. for 1 minute to form a pattern-forming film.
The mask was masked with an ArF excimer laser exposure machine so as to have a line-and-space shape (line width 100 nm, space width 100 nm), and exposure was performed using a commercially available ArF resist. Then, after firing on a hot plate at 105 ° C. for 1 minute, a line-and-space pattern was prepared by immersing the developer.
Next, this pattern sample is subjected to oxygen plasma treatment (100 sccm, 4 Pa, 100 W, 60 seconds) on the substrate by an ICP plasma etching apparatus (manufactured by Tokyo Electron Limited) to remove the photoresist and form a pattern forming film. A line-and-space pattern was formed. Then, the metal was introduced into the pattern-forming film in the same manner as in the evaluation of the metal introduction rate of the copolymer. Using this pattern as a mask, plasma treatment (100 sccm, 0.4 Pa, 200 W, 120 seconds) is performed with an ICP plasma etching apparatus (manufactured by Tokyo Electron Limited) using _{ethane hexafluoride (C 2} F _{6) and Ar gas to silicon.} The oxide film was dry-etched.

[Evaluation of etching processability]
A scanning electron microscope (SEM) JSM7800F (manufactured by JEOL Ltd.) was used to examine the cross-section of the silicon oxide film before and after plasma treatment using ethane hexafluoride (C ₂ F _{6) and Ar gas with an acceleration voltage of 1.} Observed at 5 kV, emission current 37.0 μA, and magnification 100,000 times, the thickness of the metal-introduced pattern-forming film (thickness c in FIG. 2 (b) and thickness c'in FIG. 2 (c)) , The depth processed into the silicon oxide film portion (depth d in FIG. 2C) was measured. Then, the etching selectivity was calculated by the following formula.
Etching selectivity = Processing depth to silicon oxide film / (Thickness of pattern forming film before plasma treatment-Thickness of pattern forming film after plasma treatment)
Then, the etching processability was evaluated according to the following criteria.
A: Etching selectivity of 10 or more B: Etching selectivity of 2 or more and less than 10 C: Etching selectivity of less than 2

(Example 5)
Examples except that trimethyl borate (B (OCH ₃ ) ₃ ) gas was used _{instead of TMA (trimethylaluminum, Al (CH 3} ) ₃ ) gas when introducing a metal into the pattern forming film in Example 1. Various evaluations were performed in the same manner as in 1.

(Comparative Example 1)
Examples except that trimethyl borate (B (OCH ₃ ) ₃ ) gas was used _{instead of TMA (trimethylaluminum, Al (CH 3} ) ₃ ) gas when introducing a metal into the pattern forming film in Example 1. Various evaluations were performed in the same manner as in 3.

[Measurement of B content]
A concentration profile of element B (nucleus radius 0.087 nm) in the film thickness direction was obtained by the same method as in [Measurement of Al content] described above.
The "B content in the film" shown in Table 3 is calculated from the obtained depth profile and corresponds to the total measurement of the B element content in the film.
The “maximum B content” shown in Table 3 is the B element content at the point where the B element concentration in the film in each profile is maximum.
The “B content at 1/2 of the total film thickness” shown in Table 3 is the B element content at the intermediate point of the film thickness of each profile.
The "A / B ratio" shown in Table 3 is the ratio of the B element content calculated by the following formula.
A / B ratio = maximum B element content / B content at 1/2 of the total film thickness

(Example 6)
Example 1 except that trimethylantimony (Sb (CH ₃ ) ₃ ) gas was used _{instead of TMA (trimethylaluminum, Al (CH 3} ) ₃ ) gas when introducing the metal into the pattern forming film in Example 1. Various evaluations were performed in the same manner as above.

[Measurement of Sb content]
The concentration profile of the Sb element (nucleus radius 0.133 nm) in the film thickness direction was obtained by the same method as the above-mentioned [Measurement of Al content].
The “Sb content in the film” shown in Table 4 is calculated from the obtained depth profile and corresponds to the total measurement of the Sb element content in the film.
The “maximum B content” shown in Table 4 is the Sb element content at the point where the Sb element concentration in the film in each profile is maximum.
The “Sb content at 1/2 of the total film thickness” shown in Table 4 is the Sb element content at the intermediate point of the film thickness of each profile.
The “A / B ratio” shown in Table 4 is the ratio of the Sb element content calculated by the following formula.
A / B ratio = maximum Sb element content / Sb content at 1/2 of the total film thickness

(Comparative Example 2)
Example 1 except that trimethylindium (In (CH ₃ ) ₃ ) gas was used _{instead of TMA (trimethylaluminum, Al (CH 3} ) ₃ ) gas when introducing a metal into the pattern forming film in Example 1. Various evaluations were performed in the same manner as above.

[Measurement of In content]
The concentration profile of the In element (nucleus radius 0.156 nm) in the film thickness direction was obtained by the same method as the above-mentioned [Measurement of Al content].
The "In content in the film" shown in Table 5 is calculated from the obtained depth profile and corresponds to the total measurement of the In element content in the film.
The "maximum In content" shown in Table 5 is the In element content at the point where the In element concentration in the film in each profile is maximum.
The "In content at 1/2 of the total film thickness" shown in Table 5 is the In element content at the intermediate point of the film thickness of each profile.
The “A / B ratio” shown in Table 5 is the ratio of the In element content calculated by the following formula.
A / B ratio = maximum In element content / In content at 1/2 of total film thickness

In Table 1, the nuclear radii are E Crementi, DL Ramondo, WP Reinhardt (1963), J Chem Phys. It is a value based on the description of 38: 2686.

In the example, since the condition of 2 ≦ Pr / Mr ≦ 3.3 was satisfied, the etching processability was good. On the other hand, in the comparative example in which the condition of 2 ≦ Pr / Mr ≦ 3.3 was not satisfied, the etching processability was inferior.

10 Substrate 20 Pattern forming film

Claims

A pattern-forming composition containing a polymer.
Let Pr be the free volume radius of the polymer.
When the nuclear radius of the metal introduced when forming a pattern from the pattern-forming composition is Mr.
A composition for pattern formation that satisfies the condition of 2 ≦ Pr / Mr ≦ 3.3.
When the pattern-forming composition is applied onto a substrate to form a pattern-forming film having a thickness of 300 nm, and a metal gas is introduced into the pattern-forming film under a pressure of 500 Pa for 300 seconds.
The total content of the metal contained in the pattern forming film is 4.0 atom% or more.
When the maximum metal content in the thickness direction of the pattern forming film is Aatom% and the metal content at the intermediate point in the thickness direction of the pattern forming film is Batom%, the A / B value is 10.0 or less. The pattern-forming composition according to claim 1.
The pattern-forming composition according to claim 1 or 2, wherein the polymer contains a unit derived from a sugar derivative.
The pattern-forming unit according to claim 3, wherein the unit derived from the sugar derivative includes at least one selected from the structure represented by the following general formula (103) and the structure represented by the following general formula (104). Composition;

In the general formulas (103) and (104), R 1 independently represents a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group, an acyl group, an aryl group, a trimethylsilyl group or a phosphoryl group, and a plurality of them. Some R 1s may be the same or different; R 5 represents a hydrogen atom or an alkyl group; X 1 and Y 1 each independently represent a single bond or a linking group; r represents an integer greater than or equal to 1. represents, * or mark represents any one of the binding sites of R 1 when r is 2 or more, or any one of the binding sites of the oxygen atom R 1 in place of R 1 is attached Represent.
The pattern-forming composition according to claim 4, wherein the polymer further has a structure represented by the following general formula (105);

In the general formula (105), W 1 represents a carbon atom or a silicon atom, and W 2 represents -CR 2- , -O-, -S- or -SiR 2- (where R is a hydrogen atom or carbon. Represents an alkyl group having a number of 1 to 5, and a plurality of Rs may be the same or different); R 11 represents a hydrogen atom, an alkyl group having 1 or more and 3 or less carbon atoms or a hydroxyl group, and R 12 Represents a hydrogen atom, a hydroxyl group, an acetyl group, a methoxycarbonyl group, an aryl group, an allyl group, a glycidyl ether group, a glycidyl ester group, an isocyanate ester group or a pyridyl group.
The pattern formation according to any one of claims 1 to 5, wherein the polymer contains a unit derived from a sugar derivative, and the content of the unit derived from the sugar derivative in the polymer is 60 to 90% by mass. Composition for.
The pattern-forming composition according to any one of claims 1 to 6, which is a pattern-forming mask material.
A step of applying a pattern-forming composition containing a polymer onto a substrate to form a pattern-forming film, and
A pattern forming method including a step of introducing a metal into at least a part of the pattern forming film to obtain a metal-containing pattern forming film.
Let Pr be the free volume radius of the polymer.
When the nucleus radius of the metal is Mr,
A pattern forming method that satisfies the condition of 2 ≦ Pr / Mr ≦ 3.3.
The total content of the metal contained in the metal-containing pattern forming film is 4.0 atom% or more.
When the maximum metal content in the thickness direction of the metal-containing pattern forming film is Aatom% and the metal content at the midpoint in the thickness direction of the pattern forming film is Batom%, the A / B value is 10. The pattern forming method according to claim 8, wherein the pattern is 0 or less.
The pattern forming method according to claim 8 or 9, further comprising a step of forming a pattern on the pattern forming film after the step of forming the pattern forming film.
The pattern forming method according to any one of claims 8 to 10, further comprising an etching step after the step of obtaining the metal-containing pattern forming film.