JP2023010747A - Film-forming material for lithography, film-forming composition for lithography, underlay film for lithography and patterning method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film-forming material for lithography or the like that can employ a wet process and is useful for forming a photoresist underlay film having excellent heat resistance, etching resistance, step substrate embedding properties and film surface smoothness.

SOLUTION: The present invention provides a film-forming material for lithography containing an oxazine compound.

SELECTED DRAWING: None

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention provides a film-forming material for lithography, a film-forming composition for lithography containing the material, an underlayer film for lithography formed using the composition, and a pattern-forming method using the composition (e.g., a resist pattern). method or circuit pattern method).

2. Description of the Related Art In the manufacture of semiconductor devices, microfabrication is performed by lithography using photoresist materials. In recent years, as the integration density and speed of LSIs have increased, there has been a demand for further miniaturization based on pattern rules. In lithography using photoexposure, which is currently used as a general-purpose technique, the intrinsic resolution limit due to the wavelength of the light source is approaching.

The light source for lithography used for resist pattern formation has been shortened from KrF excimer laser (248 nm) to ArF excimer laser (193 nm). However, as the resist pattern becomes finer and finer, a resolution problem or a problem that the resist pattern collapses after development occurs. However, simply thinning the resist makes it difficult to obtain a resist pattern with a film thickness sufficient for substrate processing. Therefore, in addition to the resist pattern, there is a need for a process in which a resist underlayer film is formed between the resist and the semiconductor substrate to be processed, and this resist underlayer film also functions as a mask during substrate processing.

At present, various types of resist underlayer films are known for such processes. For example, unlike conventional resist underlayer films with a high etching rate, terminal groups are removed by applying a predetermined energy to realize a resist underlayer film for lithography that has a dry etching rate selectivity close to that of resist. An underlayer film-forming material for multi-layer resist processes has been proposed which contains a solvent and a resin component having at least a substituent group which is separated to form a sulfonic acid residue (see Patent Document 1). In addition, a resist underlayer film material containing a polymer having a specific repeating unit has been proposed as a material for realizing a resist underlayer film for lithography having a dry etching rate selectivity ratio lower than that of a resist (see Patent Document 2). .). Furthermore, in order to realize a resist underlayer film for lithography having a dry etching rate selectivity ratio smaller than that of a semiconductor substrate, acenaphthylene repeating units and repeating units having a substituted or unsubstituted hydroxy group are copolymerized. A resist underlayer film material containing a polymer has been proposed (see Patent Document 3).

On the other hand, an amorphous carbon underlayer film formed by CVD using methane gas, ethane gas, acetylene gas, etc. as raw materials is well known as a material having high etching resistance in this type of resist underlayer film.

In addition, the present inventors have found that a naphthalene formaldehyde polymer containing a specific structural unit and an organic solvent are used as materials that are excellent in optical properties and etching resistance, are soluble in solvents, and can be subjected to wet processes. A film-forming composition has been proposed (see Patent Documents 4 and 5).

Regarding the method of forming the intermediate layer used in the formation of the resist underlayer film in the three-layer process, for example, a method of forming a silicon nitride film (see Patent Document 6) and a method of forming a silicon nitride film by CVD (see Patent Document 7). ) are known. Materials containing silsesquioxane-based silicon compounds are also known as intermediate layer materials for three-layer processes (
See Patent Documents 8 and 9. ).

JP-A-2004-177668 JP 2004-271838 A JP-A-2005-250434 WO2009/072465 WO2011/034062 JP-A-2002-334869 WO2004/066377 Japanese Patent Application Laid-Open No. 2007-226170 JP 2007-226204 A

As mentioned above, many conventional film-forming materials for lithography have been proposed. There is no material that satisfies both the embedding property in a stepped substrate and the flatness of the film at a high level, and the development of a new material is required.

The present invention has been made in view of the above problems, and its object is to provide a photoresist underlayer that is applicable to a wet process and has excellent heat resistance, etching resistance, embedding characteristics for stepped substrates, and film flatness. An object of the present invention is to provide a film-forming material for lithography useful for forming a film, a composition for forming a film for lithography containing the material, and an underlayer film for lithography and a method for forming a pattern using the composition. .

［式中、
Ｒ^１及びＲ^２は、独立して、炭素数１～３０の有機基であり、
Ｒ^３～Ｒ^６は、独立して、水素又は炭素数１～６の炭化水素基であり、
Ｘは、単結合、－Ｏ－、－Ｓ－、－Ｓ－Ｓ－、－ＳＯ₂－、－ＣＯ－、－ＣＯＮＨ－、
－ＮＨＣＯ－、－Ｃ（ＣＨ₃）₂－、－Ｃ（ＣＦ₃）₂－、－（ＣＨ₂）_m－、－Ｏ－（ＣＨ₂
）_m－Ｏ－、又は－Ｓ－（ＣＨ₂）_m－Ｓ－であり、
ｍは１～６の整数であり、
Ｙは、独立して、単結合、－Ｏ－、－Ｓ－、－ＣＯ－、－Ｃ（ＣＨ₃）₂－、－Ｃ（ＣＦ
₃）₂－、又は炭素数１～３のアルキレンである］。
［４］
下記式（０）の基：

（式（０）中、Ｒは各々独立して、水素原子及び炭素数１～４のアルキル基からなる群よ
り選ばれる）
を有する化合物をさらに含有する、［１］～［３］のいずれかに記載のリソグラフィー用
膜形成材料。
［５］
架橋剤をさらに含有する、［１］～［４］のいずれかに記載のリソグラフィー用膜形成
材料。
［６］
前記架橋剤が、フェノール化合物、エポキシ化合物、シアネート化合物、アミノ化合物
、メラミン化合物、グアナミン化合物、グリコールウリル化合物、ウレア化合物、イソシ
アネート化合物及びアジド化合物からなる群より選ばれる少なくとも１種である、［５］
に記載のリソグラフィー用膜形成材料。
［７］
架橋促進剤をさらに含有する、［１］～［６］のいずれか一項に記載のリソグラフィー
用膜形成材料。
［８］
ラジカル重合開始剤をさらに含有する、［１］～［７］のいずれか一項に記載のリソグ
ラフィー用膜形成材料。
［９］
［１］～［８］のいずれか一項に記載のリソグラフィー用膜形成材料と溶媒とを含有す
る、リソグラフィー用膜形成用組成物。
［１０］
酸発生剤をさらに含有する、［９］に記載のリソグラフィー用膜形成用組成物。
［１１］
リソグラフィー用膜がリソグラフィー用下層膜である、［１０］に記載のリソグラフィ
ー用膜形成用組成物。
［１２］
［１１］に記載のリソグラフィー用膜形成用組成物を用いて形成される、リソグラフィ
ー用下層膜。
［１３］
基板上に、［１１］に記載のリソグラフィー用膜形成用組成物を用いて下層膜を形成す
る工程、
該下層膜上に、少なくとも１層のフォトレジスト層を形成する工程、及び
該フォトレジスト層の所定の領域に放射線を照射し、現像を行う工程、
を含む、レジストパターン形成方法。
［１４］
基板上に、［１１］に記載のリソグラフィー用膜形成用組成物を用いて下層膜を形成す
る工程、
該下層膜上に、珪素原子を含有するレジスト中間層膜材料を用いて中間層膜を形成する
工程、
該中間層膜上に、少なくとも１層のフォトレジスト層を形成する工程、
該フォトレジスト層の所定の領域に放射線を照射し、現像してレジストパターンを形成
する工程、
該レジストパターンをマスクとして前記中間層膜をエッチングする工程、
得られた中間層膜パターンをエッチングマスクとして前記下層膜をエッチングする工程
、及び
得られた下層膜パターンをエッチングマスクとして基板をエッチングすることで基板に
パターンを形成する工程、
を含む、回路パターン形成方法。
［１５］
［１］～［８］のいずれか一項に記載のリソグラフィー用膜形成材料を、溶媒に溶解さ
せて有機相を得る工程と、
前記有機相と酸性の水溶液とを接触させて、前記リソグラフィー用膜形成材料中の不純
物を抽出する第一抽出工程と、
を含み、
前記有機相を得る工程で用いる溶媒が、水と任意に混和しない溶媒を含む、精製方法。 Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by using a compound having a specific structure, and have completed the present invention. That is, the present invention is as follows.
[1]
A film-forming material for lithography containing an oxazine compound.
[2]
Film formation for lithography according to [1], wherein the oxazine compound comprises a six-membered ring containing one oxygen atom, one nitrogen atom and four carbon atoms as ring member atoms and a condensed ring with an aromatic ring. material.
[3]
The film-forming material for lithography according to [2], wherein the oxazine compound is at least one compound selected from the group consisting of compounds represented by the following formulas (a) to (f).

[In the formula,
R ¹ and R ² are independently an organic group having 1 to 30 carbon atoms,
R ³ to R ⁶ are independently hydrogen or a hydrocarbon group having 1 to 6 carbon atoms,
X is a single bond, -O-, -S-, -S-S-, -SO ₂ -, -CO-, -CONH-,
—NHCO—, —C(CH ₃ ) ₂ —, —C(CF ₃ ) ₂ —, —(CH ₂ ) _m —, —O—(CH ₂
) _m —O—, or —S—(CH ₂ ) _m —S—;
m is an integer from 1 to 6,
Y is independently a single bond, -O-, -S-, -CO-, -C(CH ₃ ) ₂ -, -C(CF
₃ ) _2- or alkylene having 1 to 3 carbon atoms].
[4]
A group of the following formula (0):

(In formula (0), each R is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms)
The film-forming material for lithography according to any one of [1] to [3], further comprising a compound having
[5]
The film-forming material for lithography according to any one of [1] to [4], further comprising a cross-linking agent.
[6]
The cross-linking agent is at least one selected from the group consisting of phenol compounds, epoxy compounds, cyanate compounds, amino compounds, melamine compounds, guanamine compounds, glycoluril compounds, urea compounds, isocyanate compounds and azide compounds, [5]
3. The film-forming material for lithography according to .
[7]
The film-forming material for lithography according to any one of [1] to [6], further comprising a cross-linking accelerator.
[8]
The film-forming material for lithography according to any one of [1] to [7], further comprising a radical polymerization initiator.
[9]
A composition for forming a film for lithography, containing the film-forming material for lithography according to any one of [1] to [8] and a solvent.
[10]
The film-forming composition for lithography according to [9], further comprising an acid generator.
[11]
The film-forming composition for lithography according to [10], wherein the film for lithography is an underlayer film for lithography.
[12]
An underlayer film for lithography, which is formed using the composition for forming a film for lithography according to [11].
[13]
forming an underlayer film on a substrate using the film-forming composition for lithography according to [11];
a step of forming at least one layer of photoresist layer on the underlayer film; and a step of irradiating a predetermined region of the photoresist layer with radiation and developing;
A method of forming a resist pattern, comprising:
[14]
forming an underlayer film on a substrate using the film-forming composition for lithography according to [11];
forming an intermediate layer film on the underlayer film using a resist intermediate layer film material containing silicon atoms;
forming at least one photoresist layer on the intermediate layer film;
a step of irradiating a predetermined region of the photoresist layer with radiation and developing to form a resist pattern;
etching the intermediate layer film using the resist pattern as a mask;
Etching the underlayer film using the obtained intermediate layer film pattern as an etching mask; and Etching the substrate using the obtained underlayer film pattern as an etching mask to form a pattern on the substrate;
A method of forming a circuit pattern, comprising:
[15]
a step of dissolving the film-forming material for lithography according to any one of [1] to [8] in a solvent to obtain an organic phase;
a first extraction step of contacting the organic phase with an acidic aqueous solution to extract impurities in the film-forming material for lithography;
including
A purification method, wherein the solvent used in the step of obtaining the organic phase comprises a solvent optionally immiscible with water.

INDUSTRIAL APPLICABILITY According to the present invention, a film-forming material for lithography which is applicable to a wet process and is useful for forming a photoresist underlayer film having excellent heat resistance, etching resistance, embedding characteristics in a stepped substrate, and film flatness. , a composition for forming a film for lithography containing the material, and an underlayer film for lithography and a method for forming a pattern using the composition.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The following embodiments are examples for explaining the present invention, and the present invention is not limited only to these embodiments.

[Film forming material for lithography]
A film-forming material for lithography, which is one embodiment of the present invention, contains an oxazine compound.

The content of the oxazine compound in the film-forming material for lithography of the present embodiment is preferably 5 to 100% by mass, more preferably 51 to 100% by mass, more preferably 60 to 100% by mass, from the viewpoint of heat resistance. It is more preferably 100% by mass, even more preferably 70 to 100% by mass, and particularly preferably 80 to 100% by mass.

The oxazine compound used in the film forming material for lithography of the present embodiment is not particularly limited, but from the viewpoint of raw material availability and production corresponding to mass production, one oxygen atom, one nitrogen atom It preferably includes a 6-membered ring containing 4 carbon atoms and a fused ring with an aromatic ring. Here, an oxazine compound in which the aromatic ring is a benzene ring is also referred to as a benzoxazine compound, and an oxazine compound in which the aromatic ring is a naphthalene ring is also referred to as a naphthoxazine compound.

As the oxazine compound, compounds represented by the following general formulas (a) to (f) are preferable from the viewpoint of etching resistance. In the general formulas below, the bond shown toward the center of the ring indicates that it is bonded to any carbon that constitutes the ring and to which a substituent can be bonded.

In general formulas (a) to (f),
R ¹ and R ² are independently an organic group having 1 to 30 carbon atoms,
R ³ to R ⁶ are independently hydrogen or a hydrocarbon group having 1 to 6 carbon atoms,
X is a single bond, -O-, -S-, -S-S-, -SO ₂ -, -CO-, -CONH-,
—NHCO—, —C(CH ₃ ) ₂ —, —C(CF ₃ ) ₂ —, —(CH ₂ ) _m —, —O—(CH ₂
) _m —O—, or —S—(CH ₂ ) _m —S—;
m is an integer from 1 to 6,
Y is independently a single bond, -O-, -S-, -CO-, -C(CH ₃ ) ₂ -, -C(CF
₃ ) _2- or alkylene having 1 to 3 carbon atoms;

In addition, oxazine compounds include oligomers and polymers having oxazine structures in side chains,
Oligomers and polymers having an oxazine structure in the main chain are included.

Oxazine compound, International Publication 2004/009708 pamphlet, JP-A-11-
12258 and JP-A-2004-352670.

The film-forming material for lithography of this embodiment can be applied to a wet process. In addition, the film-forming material for lithography of the present embodiment has an aromatic structure and a rigid oxazine skeleton. express sexuality. As a result, deterioration of the film during high-temperature baking is suppressed,
An underlayer film having excellent etching resistance to oxygen plasma etching or the like can be formed. Furthermore, the film-forming material for lithography of the present embodiment has high solubility in organic solvents and high solubility in safe solvents in spite of having an aromatic structure. Furthermore, the underlayer film for lithography made of the composition for forming a film for lithography according to the present embodiment, which will be described later, is excellent in embedding characteristics in stepped substrates and film flatness, and not only has good stability in product quality, but also resist Excellent adhesion to the layer and the resist intermediate layer film material makes it possible to obtain an excellent resist pattern.

（式（０）中、Ｒは各々独立して、水素原子及び炭素数１～４のアルキル基からなる群よ
り選ばれる）
を有する化合物（以下、本明細書において「マレイミド化合物」ということがある。）を
さらに含有することが好ましい。マレイミド化合物は、例えば、分子内に１個以上の第１
級アミノ基を有する化合物と無水マレイン酸との脱水閉環反応により得ることができる。
また、例えば、無水マレイン酸の代わりに無水シトラコン酸等を使用して同様にメチルマ
レイミド化されたもの等も含まれる。マレイミド化合物としては、例えば、ポリマレイミ
ド化合物及びマレイミド樹脂を挙げることができる。
[Maleimide compound]
The film-forming material for lithography, which is one embodiment of the present invention, has the following formula (0)
base of:

(In formula (0), each R is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms)
(hereinafter sometimes referred to as "maleimide compound" in this specification). The maleimide compound has, for example, one or more first
It can be obtained by a dehydration ring-closure reaction between a compound having a secondary amino group and maleic anhydride.
In addition, for example, those similarly methylmaleimidated by using citraconic anhydride or the like instead of maleic anhydride are also included. Examples of maleimide compounds include polymaleimide compounds and maleimide resins.

The content of the maleimide compound in the film-forming material for lithography of the present embodiment is preferably 51 to 95% by mass, more preferably 60 to 95% by mass, from the viewpoint of heat resistance and etching resistance. , More preferably 70 to 95% by mass, 80 to
95% by mass is particularly preferred.

As the polymaleimide compound and maleimide resin used in the film-forming material for lithography of the present embodiment, bismaleimide compounds and addition polymerizable maleimide resins are preferable from the viewpoint of raw material availability and production corresponding to mass production.

式（１）中、Ｚはヘテロ原子を含んでいてもよい炭素数１～１００の２価の炭化水素基
である。炭化水素基の炭素数は、１～８０、１～６０、１～４０、１～２０等であっても
よい。ヘテロ原子としては、酸素、窒素、硫黄、フッ素、ケイ素等を挙げることができる
。 <Bismaleimide compound>
The bismaleimide compound is preferably a compound represented by the following formula (1).

In formula (1), Z is a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a heteroatom. The number of carbon atoms in the hydrocarbon group may be 1-80, 1-60, 1-40, 1-20, and the like. Heteroatoms include oxygen, nitrogen, sulfur, fluorine, silicon, and the like.

式（１Ａ）中、
Ｘはそれぞれ独立に、単結合、－Ｏ－、－ＣＨ_２－、－Ｃ（ＣＨ_３）_２－、－ＣＯ－、
－Ｃ（ＣＦ_３）_２－、－ＣＯＮＨ－又は－ＣＯＯ－であり、
Ａは、単結合、酸素原子、ヘテロ原子（例えば、酸素、窒素、硫黄、フッ素）を含んで
いてもよい炭素数１～８０の２価の炭化水素基であり、
Ｒ_１はそれぞれ独立に、ヘテロ原子（例えば、酸素、窒素、硫黄、フッ素、塩素、臭素
、ヨウ素）を含んでいてもよい炭素数０～３０の基であり、
ｍ１はそれぞれ独立に、０～４の整数である。 The bismaleimide compound is more preferably a compound represented by the following formula (1A).

In formula (1A),
Each X is independently a single bond, —O—, —CH ₂ —, —C(CH ₃ ) ₂ —, —CO—,
-C(CF ₃ ) ₂ -, -CONH- or -COO-,
A is a divalent hydrocarbon group having 1 to 80 carbon atoms which may contain a single bond, an oxygen atom, a heteroatom (e.g., oxygen, nitrogen, sulfur, fluorine),
each R ₁ is independently a group having 0 to 30 carbon atoms optionally containing a heteroatom (e.g., oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine);
Each m1 is independently an integer of 0-4.

Ｙは単結合、－Ｏ－、－ＣＨ_２－、－Ｃ（ＣＨ_３）_２－、－Ｃ（ＣＦ_３）_２－、

であり、
Ｒ_１はそれぞれ独立に、ヘテロ原子（例えば、酸素、窒素、硫黄、フッ素、塩素、臭素
、ヨウ素）を含んでいてもよい炭素数０～３０の基であり、
ｎは、０～２０の整数であり、
ｍ１及びｍ２はそれぞれ独立に、０～４の整数である。 More preferably, from the viewpoint of improving heat resistance and etching resistance, in formula (1A),
Each X is independently a single bond, —O—, —CH ₂ —, —C(CH ₃ ) ₂ —, —CO—,
-C(CF ₃ ) ₂ -, -CONH- or -COO-,
A is a single bond, an oxygen atom, -(CH ₂ ) _n -, -CH ₂ C(CH ₃ ) ₂ CH ₂ -, -(
C(CH ₃ ) ₂ ) _n —, —(O(CH ₂ ) _m2 ) _n —, —(O(C ₆ H ₄ )) _n —, or any of the following structures:

Y is a single bond, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -,

and
each R ₁ is independently a group having 0 to 30 carbon atoms optionally containing a heteroatom (e.g., oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine);
n is an integer from 0 to 20,
m1 and m2 are each independently an integer of 0-4.

X is preferably a single bond from the viewpoint of heat resistance, and -COO from the viewpoint of solubility.
- is preferred.
From the viewpoint of improving heat resistance, Y is preferably a single bond.
R ₁ is preferably a group having 0 to 20 or 0 to 10 carbon atoms which may contain heteroatoms (eg, oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine). From the viewpoint of improving solubility in organic solvents, R ₁ is preferably a hydrocarbon group. For example, as R ₁
Examples include alkyl groups (eg, alkyl groups having 1 to 6 or 1 to 3 carbon atoms), and specific examples include methyl groups and ethyl groups.
m1 is preferably an integer of 0 to 2, from the viewpoint of raw material availability and solubility improvement,
1 or 2 is more preferred.
m2 is preferably an integer of 2-4.
n is preferably an integer of 0 to 2, and more preferably an integer of 1 to 2 from the viewpoint of improving heat resistance.

ｎ１は１～１０の整数であり、
ｎ２は１～４の整数であり、
ｎ３は１～２０の整数であり、
Ｙは－Ｃ（ＣＨ_３）_２－又は－Ｃ（ＣＦ_３）_２－であり、
Ｒ_１はそれぞれ独立に、アルキル基（例えば、炭素数１～６又は１～３のアルキル基）
であり、
ｍ１はそれぞれ独立に、０～４の整数である。 One embodiment of the compound represented by formula (1A) is
each X is independently a single bond, -O-, -CO-, or -COO-;
A is a single bond, an oxygen atom, -(CH ₂ ) _n1 -, -CH ₂ C(CH ₃ ) ₂ CH ₂ -, -
(O(CH ₂ ) _n2 ) _n3 —, or the structure

n1 is an integer from 1 to 10,
n2 is an integer from 1 to 4,
n3 is an integer from 1 to 20,
Y is -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -;
Each R ₁ is independently an alkyl group (eg, an alkyl group having 1 to 6 or 1 to 3 carbon atoms)
and
Each m1 is independently an integer of 0-4.

One embodiment of the compound represented by formula (1A) is
X is a single bond,
A is -(CH ₂ ) _n1 -,
n1 is an integer from 1 to 10,
Each R ₁ is independently an alkyl group (eg, an alkyl group having 1 to 6 or 1 to 3 carbon atoms)
and
Each m1 is independently an integer of 0-4.
Here, n1 is preferably 1-6 or 1-3.

One embodiment of the compound represented by formula (1A) is
each X is independently -CO- or -COO-,
A is -(O(CH ₂ ) _n2 ) _n3 -,
n2 is an integer from 1 to 4,
n3 is an integer from 1 to 20,
Each R ₁ is independently an alkyl group (eg, an alkyl group having 1 to 6 or 1 to 3 carbon atoms)
and
Each m1 is independently an integer of 0-4.
Here, -XAX- is preferably -CO-(O(CH ₂ ) _n2 ) _n3 -COO-.

であり、
Ｙは－Ｃ（ＣＨ_３）_２－又は－Ｃ（ＣＦ_３）_２－であり、
Ｒ_１はそれぞれ独立に、アルキル基（例えば、炭素数１～６又は１～３のアルキル基）
であり、
ｍ１はそれぞれ独立に、０～４の整数である。
ここで、Ａは以下の構造

であることが好ましい。 One embodiment of the compound represented by formula (1A) is
X is -O-,
A has the following structure

and
Y is -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -;
Each R ₁ is independently an alkyl group (eg, an alkyl group having 1 to 6 or 1 to 3 carbon atoms)
and
Each m1 is independently an integer of 0-4.
where A is the following structure

is preferably

式（１Ｂ）中、Ｚ１はヘテロ原子を含んでいてもよい炭素数１～１００の２価の直鎖状
、分岐状、あるいは環状の炭化水素基である。ヘテロ原子としては、酸素、窒素、硫黄、
フッ素、ケイ素等を挙げることができる。 The bismaleimide compound is preferably a compound represented by the following formula (1B).

In formula (1B), Z1 is a divalent linear, branched or cyclic hydrocarbon group having 1 to 100 carbon atoms which may contain a heteroatom. Heteroatoms include oxygen, nitrogen, sulfur,
Fluorine, silicon and the like can be mentioned.

<Addition polymerization type maleimide resin>
The addition polymerization type maleimide resin is preferably a resin represented by the following formula (2) or the following formula (3) from the viewpoint of improving etching resistance.

In formula (2), each R ₂ is independently a group having 0 to 10 carbon atoms which may contain a heteroatom (eg, oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine). Also, _R2
is preferably a hydrocarbon group from the viewpoint of improving solubility in an organic solvent. For example, R
₂ includes an alkyl group (eg, an alkyl group having 1 to 6 or 1 to 3 carbon atoms),
Specific examples include a methyl group and an ethyl group.
Each m2 is independently an integer of 0 to 3. In addition, m2 is preferably 0 or 1, and more preferably 0 from the viewpoint of raw material availability.
Each m2' is independently an integer of 0-4. In addition, m2' is preferably 0 or 1, and more preferably 0 from the viewpoint of raw material availability.
n is an integer of 0-4. Also, n is preferably an integer of 1 to 4 or 0 to 2, and more preferably an integer of 1 to 2 from the viewpoint of improving heat resistance.

In the above formula (3), R ₃ and R ₄ each independently represent a heteroatom (e.g., oxygen, nitrogen,
a group having 0 to 10 carbon atoms which may contain sulfur, fluorine, chlorine, bromine, iodine); Moreover, from the viewpoint of improving the solubility in organic solvents, R ₃ and R ₄ are preferably hydrocarbon groups. Examples of R ₃ and R ₄ include alkyl groups (eg, alkyl groups having 1 to 6 or 1 to 3 carbon atoms) and the like, and specific examples include methyl and ethyl groups.
Each m3 is independently an integer of 0 to 4. Further, m3 is preferably an integer of 0 to 2, and more preferably 0 from the viewpoint of raw material availability.
Each m4 is independently an integer of 0-4. Further, m4 is preferably an integer of 0 to 2, and more preferably 0 from the viewpoint of raw material availability.
n is an integer from 0 to 4; Also, n is preferably an integer of 1 to 4 or 0 to 2, and more preferably an integer of 1 to 2 from the viewpoint of raw material availability.

The film-forming material for lithography of this embodiment can be applied to a wet process. In addition, the film-forming material for lithography of the present embodiment has an aromatic structure and a rigid maleimide skeleton. express sexuality. As a result, deterioration of the film during high-temperature baking is suppressed, and an underlayer film having excellent etching resistance to oxygen plasma etching or the like can be formed. Furthermore, the film-forming material for lithography of the present embodiment has high solubility in organic solvents and high solubility in safe solvents in spite of having an aromatic structure. Furthermore, the underlayer film for lithography made of the composition for forming a film for lithography according to the present embodiment, which will be described later, is excellent in embedding characteristics in stepped substrates and film flatness, and not only has good stability in product quality, but also resist Excellent adhesion to the layer and the resist intermediate layer film material makes it possible to obtain an excellent resist pattern.

Specifically, the bismaleimide compound used in the present embodiment is m-phenylenebismaleimide, 4-methyl-1,3-phenylenebismaleimide, 4,4-diphenylmethanebismaleimide, 4,4'-diphenylsulfone. bismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene,
phenylene skeleton-containing bismaleimides such as 1,4-bis(3-maleimidophenoxy)benzene, 1,4-bis(4-maleimidophenoxy)benzene; bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, 1,1-bis(3-ethyl-5-methyl-4-
maleimidophenyl)ethane, 2,2-bis(3-ethyl-5-methyl-4-maleimidophenyl)propane, N,N′-4,4′-[3,3′-dimethyl-diphenylmethane]bismaleimide, N , N′-4,4′-[3,3′-dimethyl-1,1-diphenylethane]
Bismaleimide, N,N'-4,4'-[3,3'-dimethyl-1,1-diphenylpropane]bismaleimide, N,N'-4,4'-[3,3'-diethyl-diphenylmethane ] bismaleimide, N,N′-4,4′-[3,3′-di-n-propyl-diphenylmethane]bismaleimide, N,N′-4,4′-[3,3′-di-n-butyl -diphenylmethane]bismaleimide containing a diphenylalkane skeleton, N,N'-4,4'-[3,
Biphenyl skeleton-containing bismaleimide such as 3′-dimethyl-biphenylene]bismaleimide, N,N′-4,4′-[3,3′-diethyl-biphenylene]bismaleimide, 1,6-hexanebismaleimide, 1, Aliphatic backbone bismaleimides such as 6-bismaleimide-(2,2,4-trimethyl)hexane, 1,3-dimethylenecyclohexanebismaleimide, 1,4-dimethylenecyclohexanebismaleimide, and 1,3-bis( 3-aminopropyl)-1,1,2,2-tetramethyldisiloxane, 1,3-bis(3-aminobutyl)-1,1,2,2-tetramethyldisiloxane, bis(4-aminophenoxy ) dimethylsilane, 1,3-bis(4-aminophenoxy)tetramethyldisiloxane, 1,1,
3,3-tetramethyl-1,3-bis(4-aminophenyl)disiloxane, 1,1,3
,3-tetraphenoxy-1,3-bis(2-aminoethyl)disiloxane, 1,1,3
,3-tetraphenyl-1,3-bis(2-aminoethyl)disiloxane, 1,1,3,
3-tetraphenyl-1,3-bis(3-aminopropyl)disiloxane, 1,1,3,
3-tetramethyl-1,3-bis(2-aminoethyl)disiloxane, 1,1,3,3-
tetramethyl-1,3-bis(3-aminopropyl)disiloxane, 1,1,3,3-tetramethyl-1,3-bis(4-aminobutyl)disiloxane, 1,3-dimethyl-1,
3-dimethoxy-1,3-bis(4-aminobutyl)disiloxane, 1,1,3,3,5
,5-hexamethyl-1,5-bis(4-aminophenyl)trisiloxane, 1,1,5
,5-tetraphenyl-3,3-dimethyl-1,5-bis(3-aminopropyl)trisiloxane, 1,1,5,5-tetraphenyl-3,3-dimethoxy-1,5-bis(4 -
aminobutyl)trisiloxane, 1,1,5,5-tetraphenyl-3,3-dimethoxy-1,5-bis(5-aminopentyl)trisiloxane, 1,1,5,5-tetramethyl-3, 3-dimethoxy-1,5-bis(2-aminoethyl)trisiloxane, 1,1,5
,5-tetramethyl-3,3-dimethoxy-1,5-bis(4-aminobutyl)trisiloxane, 1,1,5,5-tetramethyl-3,3-dimethoxy-1,5-bis(5 -aminopentyl)trisiloxane, 1,1,3,3,5,5-hexamethyl-1,5-bis(
3-aminopropyl)trisiloxane, 1,1,3,3,5,5-hexaethyl-1,5
- Bismaleimide compounds composed of diaminosiloxanes such as bis(3-aminopropyl)trisiloxane, 1,1,3,3,5,5-hexapropyl-1,5-bis(3-aminopropyl)trisiloxane, etc. mentioned.

Among the bismaleimide compounds, bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, N,N'-4,4'-[3,3'-dimethyl-diphenylmethane]bismaleimide, N,N'-4,4'-[3,3'-diethyldiphenylmethane]bismaleimide is preferable because it is excellent in solvent solubility and heat resistance.

Examples of addition polymerization type maleimide resins used in the present embodiment include Bismaleimide M-20 (manufactured by Mitsui Toatsu Chemicals, trade name), BMI-2300 (manufactured by Daiwa Kasei Kogyo Co., Ltd.,
trade name), BMI-3200 (manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name), MIR-3000 (
manufactured by Nippon Kayaku Co., Ltd., product name) and the like. Among these, BMI-2300 is particularly preferable because it is excellent in solubility and heat resistance.

<Crosslinking agent>
In addition to the oxazine compound, the film-forming material for lithography of the present embodiment may further contain a cross-linking agent, if necessary, from the viewpoint of suppressing a decrease in curing temperature and intermixing.

The cross-linking agent is not particularly limited as long as it undergoes a cross-linking reaction with the oxazine compound, and any known cross-linking system can be applied.
Phenolic compounds, epoxy compounds, cyanate compounds, amino compounds, acrylate compounds, melamine compounds, guanamine compounds, glycoluril compounds, urea compounds, isocyanate compounds, azide compounds, etc., but not particularly limited thereto. These cross-linking agents can be used singly or in combination of two or more. Among these, epoxy compounds and cyanate compounds are preferred.

In the cross-linking reaction between an oxazine compound and a cross-linking agent, for example, the active group (phenolic hydroxyl group, epoxy group, cyanate group or amino group) possessed by these cross-linking agents is converted into phenol obtained by ring-opening the alicyclic moiety of benzoxazine. reacts with hydroxyl groups.

A well-known thing can be used as said phenol compound. For example, phenols include alkylphenols such as cresols and xylenols, polyhydric phenols such as hydroquinone, polycyclic phenols such as naphthols and naphthalene diols, and bisphenols such as bisphenol A and bisphenol F. and polyfunctional phenol compounds such as phenol novolak and phenol aralkyl resins.
From the viewpoint of heat resistance and solubility, aralkyl-type phenolic resins are preferred.

A known epoxy compound can be used as the epoxy compound, and is selected from those having two or more epoxy groups in one molecule. For example, bisphenol A, bisphenol F, 3,
3′,5,5′-tetramethyl-bisphenol F, bisphenol S, fluorene bisphenol, 2,2′-biphenol, 3,3′,5,5′-tetramethyl-4,4′-dihydroxybiphenol, resorcinol, Epoxidized dihydric phenols such as naphthalene diols, tris-(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, tris(2,3-epoxypropyl) Isocyanurate, trimethylolmethane triglycidyl ether, trimethylolpropane triglycidyl ether, triethylolethane triglycidyl ether, phenol novolak, o-cresol novolak, and other trivalent or higher phenol epoxides, dicyclopentadiene and phenol Epoxidized products of cocondensation resins, epoxidized products of phenol aralkyl resins synthesized from phenols and paraxylylene dichloride, etc., epoxidized products of biphenyl aralkyl type phenol resins synthesized from phenols and bischloromethylbiphenyl, etc., naphthols and epoxidized naphthol aralkyl resins synthesized from paraxylylene dichloride and the like. These epoxy resins may be used alone or in combination of two or more. From the viewpoint of heat resistance and solubility, epoxy resins that are solid at room temperature, such as epoxy resins obtained from phenol aralkyl resins and biphenyl aralkyl resins, are preferred.

The cyanate compound is not particularly limited as long as it is a compound having two or more cyanate groups in one molecule, and known compounds can be used. Examples thereof include those described in WO 2011108524. In the present embodiment, preferred cyanate compounds are those having a structure in which the hydroxyl group of a compound having two or more hydroxyl groups in one molecule is substituted with a cyanate group. mentioned. Further, the cyanate compound preferably has an aromatic group,
A structure in which a cyanate group is directly linked to an aromatic group can be preferably used. Examples of such cyanate compounds include bisphenol A, bisphenol F, bisphenol M, bisphenol P, bisphenol E, phenol novolak resin, cresol novolak resin, dicyclopentadiene novolak resin, tetramethylbisphenol F, bisphenol A novolak resin, bromine bisphenol A, brominated phenol novolac resin, trifunctional phenol, tetrafunctional phenol, naphthalene-type phenol, biphenyl-type phenol, phenol aralkyl resin, biphenyl aralkyl resin, naphthol aralkyl resin, dicyclopentadiene aralkyl resin, alicyclic phenol, phosphorus Examples include those having a structure in which the hydroxyl group of the contained phenol or the like is substituted with a cyanate group. You may use these cyanate compounds individually or in combination of 2 or more types as appropriate. Moreover, the cyanate compound described above may be in any form of a monomer, an oligomer, or a resin.

Examples of the amino compounds include m-phenylenediamine, p-phenylenediamine, 4,
4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-
Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4' -diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4
-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,
3-bis(3-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2
, 2-bis[4-(3-aminophenoxy)phenyl]propane, 4,4′-bis(4-
aminophenoxy)biphenyl, 4,4′-bis(3-aminophenoxy)biphenyl,
bis[4-(4-aminophenoxy)phenyl]ether, bis[4-(3-aminophenoxy)phenyl]ether, 9,9-bis(4-aminophenyl)fluorene, 9,9
-bis(4-amino-3-chlorophenyl)fluorene, 9,9-bis(4-amino-3
-fluorophenyl)fluorene, O-tolidine, m-tolidine, 4,4'-diaminobenzanilide, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 4-aminophenyl-4- Examples include aminobenzoate, 2-(4-aminophenyl)-6-aminobenzoxazole and the like. Among these, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 4,4′- diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 1
,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)
Benzene, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,
2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3
-aminophenoxy)phenyl]propane, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ether, Aromatic amines such as bis[4-(3-aminophenoxy)phenyl]ether, diaminocyclohexane, diaminodicyclohexylmethane, dimethyldiaminodicyclohexylmethane, tetramethyldiaminodicyclohexylmethane, diaminodicyclohexylpropane, diaminobicyclo[2.2.1 ] heptane,
bis(aminomethyl)-bicyclo[2.2.1]heptane, 3(4),8(9)-bis(
alicyclic amines such as aminomethyl)tricyclo[5.2.1.02,6]decane, 1,3-bisaminomethylcyclohexane, isophoronediamine, ethylenediamine, hexamethylenediamine, octamethylenediamine, decamethylenediamine, Aliphatic amines such as diethylenetriamine and triethylenetetramine are included.

Specific examples of the melamine compound include hexamethylolmelamine, hexamethoxymethylmelamine, compounds in which 1 to 6 methylol groups of hexamethylolmelamine are methoxymethylated, or mixtures thereof, hexamethoxyethylmelamine, and hexaacyloxymethyl. Examples include compounds in which 1 to 6 methylol groups of melamine and hexamethylolmelamine are acyloxymethylated, or mixtures thereof.

Specific examples of the guanamine compound include, for example, tetramethylolguanamine, tetramethoxymethylguanamine, compounds in which 1 to 4 methylol groups of tetramethylolguanamine are methoxymethylated, or mixtures thereof, tetramethoxyethylguanamine, and tetraacyloxyguanamine. , a compound obtained by acyloxymethylating 1 to 4 methylol groups of tetramethylolguanamine, or a mixture thereof.

Specific examples of the glycoluril compounds include, for example, tetramethylolglycoluril, tetramethoxyglycoluril, tetramethoxymethylglycoluril, compounds in which 1 to 4 methylol groups of tetramethylolglycoluril are methoxymethylated, or mixtures thereof; Examples include compounds in which 1 to 4 methylol groups of tetramethylolglycoluril are acyloxymethylated, or mixtures thereof.

Specific examples of the urea compound include tetramethylol urea, tetramethoxymethyl urea, compounds in which 1 to 4 methylol groups of tetramethylol urea are methoxymethylated, mixtures thereof, and tetramethoxyethyl urea.

Moreover, in the present embodiment, a cross-linking agent having at least one allyl group may be used from the viewpoint of improving the cross-linkability. Specific examples of cross-linking agents having at least one allyl group include:
2,2-bis(3-allyl-4-hydroxyphenyl)propane, 1,1,1,3,3,
3-hexafluoro-2,2-bis(3-allyl-4-hydroxyphenyl)propane,
Allylphenols such as bis(3-allyl-4-hydroxyphenyl)sulfone, bis(3-allyl-4-hydroxyphenyl)sulfide, bis(3-allyl-4-hydroxyphenyl)ether, 2,2- bis(3-allyl-4-cyanatophenyl)propane, 1
, 1,1,3,3,3-hexafluoro-2,2-bis(3-allyl-4-cyanatophenyl)propane, bis(3-allyl-4-cyanatophenyl)sulfone, bis(3- allyl-4-cyanatophenyl) sulfide, bis(3-allyl-4-cyanatophenyl)
Allyl cyanates such as ether, diallyl phthalate, diallyl isophthalate, diallyl terephthalate, triallyl isocyanurate, trimethylolpropane diallyl ether, pentaerythritol allyl ether, etc., but are limited to those exemplified above. is not. These may be used alone or as a mixture of two or more. Among these, 2,2-bis(3-allyl-4-hydroxyphenyl)propane, 1,1,1,3, 3,3-hexafluoro-2,2-bis(3-allyl-4-hydroxyphenyl)propane, bis(3-allyl-4-hydroxyphenyl)sulfone, bis(
Allylphenols such as 3-allyl-4-hydroxyphenyl)sulfide and bis(3-allyl-4-hydroxyphenyl)ether are preferred.

The film-forming material for lithography of the present embodiment can be formed into the film for lithography of the present embodiment by cross-linking and curing the oxazine compound alone or by blending the above-mentioned cross-linking agent by a known method. . Examples of cross-linking methods include methods such as heat curing and photo-curing.

The content of the cross-linking agent is, for example, 0 when the oxazine compound is 100 parts by mass.
. It is in the range of 1 to 100 parts by mass, preferably in the range of 1 to 50 parts by mass, more preferably in the range of 1 to 30 parts by mass from the viewpoint of heat resistance and solubility.

The film-forming material for lithography of the present embodiment may optionally contain a cross-linking accelerator for promoting cross-linking and curing reactions.

The cross-linking accelerator is not particularly limited as long as it promotes cross-linking and curing reaction, and examples thereof include amines, imidazoles, organic phosphines, and Lewis acids. These cross-linking accelerators can be used singly or in combination of two or more. Among these, imidazoles and organic phosphines are preferred, and imidazoles are more preferred from the viewpoint of lowering the cross-linking temperature.

Examples of the cross-linking accelerator include, but are not limited to, 1,8-diazabicyclo (
5,4,0) Tertiary amines such as undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, 2-methylimidazole, 2-phenylimidazole, 2- ethyl-
imidazoles such as 4-methylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, 2,4,5-triphenylimidazole, tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, Organic phosphines such as phenylphosphine, tetra-substituted phosphonium/tetra-substituted borate such as tetraphenylphosphonium/tetraphenylborate, tetraphenylphosphonium/ethyltriphenylborate, tetrabutylphosphonium/tetrabutylborate, 2-ethyl-4-methylimidazole and tetraphenylboron salts such as tetraphenylborate, N-methylmorpholine-tetraphenylborate, and the like.
The amount of the cross-linking accelerator compounded is usually, when the oxazine compound is 100 parts by mass,
It is preferably in the range of 0.1 to 10 parts by mass, more preferably in the range of 0.1 to 5 parts by mass from the viewpoint of ease of control and economy, and still more preferably 0.1 to 3 parts by mass. It is in the range of parts by mass.

<Radical polymerization initiator>
The film-forming material for lithography of the present embodiment may optionally contain a radical polymerization initiator. The radical polymerization initiator may be a photopolymerization initiator that initiates radical polymerization with light, or a thermal polymerization initiator that initiates radical polymerization with heat.

Such a radical polymerization initiator is not particularly limited, and conventionally used ones can be appropriately employed. For example, 1-hydroxycyclohexylphenyl ketone, benzyl dimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2 -methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-
methyl-propionyl)-benzyl]phenyl}-2-methylpropan-1-one, 2,
4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,
6-Trimethylbenzoyl)-phenylphosphine oxide and other ketone-based photopolymerization initiators, methyl ethyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, acetyl acetate peroxide, 1,1-bis(t -hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)-cyclohexane, 1,1
-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)-2-methylcyclohexane, 1,1-bis(t-butylperoxy)- cyclohexane, 1,1-bis(t-butylperoxy)cyclododecane,
1,1-bis(t-butylperoxy)butane, 2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1, 1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-hexyl hydroperoxide, t-butyl hydroperoxide, α,α'-bis(t-butylperoxy)diisopropylbenzene, dicumyl Peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-bis( t-butylperoxy)hexyne-3, isobutyryl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic acid peroxide, m-toluoyl benzoyl Peroxide, benzoyl peroxide, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis(4-t-butylcyclohexyl) peroxydicarbonate, di-2-
ethoxyethyl peroxydicarbonate, di-2-ethoxyhexyl peroxydicarbonate, di-3-methoxybutyl peroxydicarbonate, di-s-butyl peroxydicarbonate, di(3-methyl-3-methoxybutyl) peroxydicarbonate,
α,α'-bis(neodecanoylperoxy)diisopropylbenzene, cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethyl peroxyneodecanoate, t-hexyl peroxyneodecanoate, t-butyl peroxyneodecanoate, t-hexyl peroxypivalate, t-butyl peroxypivalate, 1,1,3,3 -tetramethylbutylperoxy-2-ethylhexanooate, 2,5-dimethyl-2,5-bis(2-
ethylhexanoylperoxy)hexanoate, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate ate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxyisobutyrate, t-butylperoxymalate, t-butylperoxy-3,5,5-trimethylhexanoate, t-
butyl peroxylaurate, t-butyl peroxyisopropyl monocarbonate, t
-butyl peroxy-2-ethylhexyl monocarbonate, t-butyl peroxyacetate, t-butyl peroxy-m-toluyl benzoate, t-butyl peroxybenzoate, bis(t-butyl peroxy) isophthalate, 2,5 -dimethyl-2,5-
bis(m-toluylperoxy)hexane, t-hexylperoxybenzoate, 2,
5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butyl peroxyallyl monocarbonate, t-butyltrimethylsilyl peroxide, 3,3',4,
4'-tetra(t-butylperoxycarbonyl)benzophenone, 2,3-dimethyl-
Examples include organic peroxide polymerization initiators such as 2,3-diphenylbutane.

Also, 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile, 1-[(
1-cyano-1-methylethyl)azo]formamide, 1,1′-azobis(cyclohexane-1-carbonitrile), 2,2′-azobis(2-methylbutyronitrile), 2,
2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylpropionamidine) dihydrochloride, 2,
2′-azobis(2-methyl-N-phenylpropionamidine) dihydrochloride, 2
,2′-azobis[N-(4-chlorophenyl)-2-methylpropionamidine]dihydride chloride, 2,2′-azobis[N-(4-hydrophenyl)-2-methylpropionamidine]dihydrochloride, 2 , 2′-azobis[2-methyl-N-(phenylmethyl)propionamidine] dihydrochloride, 2,2′-azobis[2-methyl-N-
(2-propenyl) propionamidine] dihydrochloride, 2,2′-azobis[N-
(2-hydroxyethyl)-2-methylpropionamidine]dihydrochloride, 2,2
'-azobis[2-(5-methyl-2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2 '-azobis[2-(4,5,6,7-tetrahydro-1H-1,3-
diazepin-2-yl)propane]dihydrochloride, 2,2′-azobis[2-(3,
4,5,6-tetrahydropyrimidin-2-yl)propane]dihydrochloride, 2,2
'-azobis[2-(5-hydroxy-3,4,5,6-tetrahydropyrimidine-2-
yl)propane]dihydrochloride, 2,2′-azobis[2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane]dihydrochloride, 2,2′-azobis[2-(2 -imidazolin-2-yl)propane], 2,2′-azobis[2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide], 2,2′-azobis[ 2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide], 2,2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide], 2,2′- Azobis(2-methylpropionamide), 2,2
'-azobis (2,4,4-trimethylpentane), 2,2'-azobis (2-methylpropane), dimethyl-2,2-azobis (2-methylpropionate), 4,4'-azobis ( 4-cyanopentanoic acid), 2,2′-azobis[2-(hydroxymethyl)propionitrile] and other azo polymerization initiators. As the radical polymerization initiator in the present embodiment, one of these may be used alone or two or more of them may be used in combination, and other known polymerization initiators may be further used in combination.

The content of the radical polymerization initiator may be a stoichiometrically necessary amount with respect to the mass of the oxazine compound.
. It is preferably from 05 to 25 parts by mass, more preferably from 0.1 to 10 parts by mass. When the content of the radical polymerization initiator is 0.05 parts by mass or more, it tends to be possible to prevent insufficient curing of the oxazine compound. If it is not more than parts by mass, it tends to be possible to prevent deterioration of the long-term storage stability at room temperature of the film-forming material for lithography.

[Method for Purifying Film-Forming Material for Lithography]
The lithographic film-forming material can be purified by washing with an acidic aqueous solution.
In the purification method, the film-forming material for lithography is dissolved in an organic solvent that is arbitrarily immiscible with water to obtain an organic phase, and the organic phase is brought into contact with an acidic aqueous solution to perform an extraction treatment (first extraction step). 3. Transferring metals contained in an organic phase containing a film-forming material for lithography and an organic solvent to an aqueous phase, and then separating the organic phase from the aqueous phase. The purification can significantly reduce the content of various metals in the film-forming material for lithography of the present invention.

The organic solvent that is arbitrarily immiscible with water is not particularly limited, but an organic solvent that can be safely applied to the semiconductor manufacturing process is preferable. The amount of the organic solvent used is usually about 1 to 100 times the weight of the compound used.

Specific examples of the organic solvent used include those described in International Publication 2015/080240. Among these, toluene, 2-heptanone, cyclohexanone, cyclopentanone, methyl isobutyl ketone, propylene glycol monomethyl ether acetate, ethyl acetate and the like are preferred, and cyclohexanone and propylene glycol monomethyl ether acetate are particularly preferred. These organic solvents can be used alone or in combination of two or more.

The acidic aqueous solution is appropriately selected from aqueous solutions in which generally known organic and inorganic compounds are dissolved in water. Examples include those described in International Publication 2015/080240. These acidic aqueous solutions can be used alone or in combination of two or more. Examples of acidic aqueous solutions include mineral acid aqueous solutions and organic acid aqueous solutions. Examples of the aqueous mineral acid solution include aqueous solutions containing one or more selected from the group consisting of hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid. Examples of aqueous organic acid solutions include acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, tartaric acid, citric acid, methanesulfonic acid, phenolsulfonic acid, p-toluenesulfonic acid and trifluoroacetic acid. An aqueous solution containing one or more selected from the group consisting of The acidic aqueous solution is preferably an aqueous solution of sulfuric acid, nitric acid, or a carboxylic acid such as acetic acid, oxalic acid, tartaric acid, or citric acid, more preferably an aqueous solution of sulfuric acid, oxalic acid, tartaric acid, or citric acid, and particularly an aqueous solution of oxalic acid. preferable. Polyvalent carboxylic acids such as oxalic acid, tartaric acid, and citric acid coordinate to metal ions and produce a chelating effect, so it is thought that more metals can be removed. Further, the water used here preferably has a low metal content, such as ion-exchanged water, in line with the object of the present invention.

The pH of the acidic aqueous solution is not particularly limited, but if the acidity of the aqueous solution is too high, it may adversely affect the compounds or resins used, which is not preferred. The pH range is usually about 0-5, more preferably about 0-3.

The amount of the acidic aqueous solution used is not particularly limited. may cause the above problem. The amount of the aqueous solution used is usually 10 to 200 parts by mass, preferably 20 to 100 parts by mass, based on the solution of the film-forming material for lithography.

The metal content can be extracted by contacting the acidic aqueous solution with a solution (B) containing a film-forming material for lithography and an organic solvent optionally immiscible with water.

The temperature at which the extraction treatment is performed is usually 20 to 90°C, preferably 30 to 80°C. The extraction operation is performed, for example, by mixing well by stirring or the like, and then allowing the mixture to stand still. As a result, the metal contained in the solution containing the compound used and the organic solvent migrates to the aqueous phase. Moreover, this operation reduces the acidity of the solution, and can suppress deterioration of the compound to be used.

After the extraction treatment, the solution phase containing the compound to be used and the organic solvent is separated from the aqueous phase, and the solution containing the organic solvent is recovered by decantation or the like. The standing time is not particularly limited, but if the standing time is too short, the separation between the solution phase containing the organic solvent and the aqueous phase becomes poor, which is not preferable. Usually, the standing time is 1 minute or longer, preferably 10 minutes or longer, and still more preferably 30 minutes or longer. In addition, although the extraction process may be performed only once,
It is also effective to repeat the operations of mixing, standing, and separating multiple times.

When such an extraction treatment is performed using an acidic aqueous solution, the organic phase containing the recovered organic solvent is extracted from the aqueous solution after the treatment, and is further extracted with water (second extraction step) is preferably performed. The extraction operation is performed by allowing the mixture to stand still after mixing well by stirring or the like. Since the obtained solution is separated into a solution phase containing the compound and the organic solvent and an aqueous phase, the solution phase is recovered by decantation or the like. Further, the water used here preferably has a low metal content, such as ion-exchanged water, in line with the object of the present invention.
The extraction process may be performed only once, but it is also effective to repeat the operations of mixing, standing, and separating multiple times. In the extraction process, conditions such as the ratio of both used, temperature, time, etc. are not particularly limited, but may be the same as in the case of the contact process with the acidic aqueous solution.

Water contained in the thus obtained solution containing the film-forming material for lithography and the organic solvent can be easily removed by performing an operation such as distillation under reduced pressure. Also, if necessary, an organic solvent can be added to adjust the concentration of the compound to an arbitrary concentration.

Methods for obtaining only the film-forming material for lithography from the obtained solution containing the organic solvent can be carried out by known methods such as removal under reduced pressure, separation by reprecipitation, and combinations thereof. If necessary, known treatments such as concentration operation, filtration operation, centrifugation operation, and drying operation can be performed.

[Composition for film formation for lithography]
The film-forming composition for lithography of this embodiment contains the film-forming material for lithography and a solvent. The lithographic film is, for example, a lithographic underlayer film.

The film-forming composition for lithography of the present embodiment can be applied to a substrate, then heated as necessary to evaporate the solvent, and then heated or irradiated with light to form a desired cured film. can. The film-forming composition for lithography of the present embodiment may be applied by any method. Roll coating method, transfer printing method, brush coating,
A method such as a blade coating method, an air knife coating method, or the like can be appropriately employed.

The heating temperature of the film is not particularly limited for the purpose of evaporating the solvent.
It can be done at 0°C. The heating method is not particularly limited. For example, a hot plate or an oven may be used to evaporate under an appropriate atmosphere such as air, an inert gas such as nitrogen, or vacuum. The heating temperature and heating time may be selected so as to suit the process steps of the intended electronic device, and the heating conditions may be selected such that the physical properties of the resulting film are suitable for the required properties of the electronic device. The conditions for light irradiation are not particularly limited either, and appropriate irradiation energy and irradiation time may be adopted according to the film-forming material for lithography to be used.

<Solvent>
The solvent used in the film-forming composition for lithography of the present embodiment is not particularly limited as long as it dissolves at least the oxazine compound, and known solvents can be used as appropriate.

Specific examples of the solvent include those described in International Publication 2013/024779. These solvents can be used singly or in combination of two or more.

Among the above solvents, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, methyl hydroxyisobutyrate, and anisole are particularly preferred from the viewpoint of safety.

The content of the solvent is not particularly limited.
It is preferably 0 parts by mass, more preferably 400 to 7,900 parts by mass,
More preferably, it is 900 to 4,900 parts by mass.

<Acid generator>
The film-forming composition for lithography of the present embodiment may optionally contain an acid generator from the viewpoint of further promoting the cross-linking reaction. As acid generators, those that generate acid by thermal decomposition, those that generate acid by light irradiation, and the like are known, and any of them can be used.

Examples of acid generators include those described in International Publication 2013/024779. Among these, in particular, triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, tris(p-tert-butoxyphenyl)sulfonium trifluoromethanesulfonate, p-toluenesulfonic acid Triphenylsulfonium, (p-tert-butoxyphenyl)diphenylsulfonium p-toluenesulfonate, tris(p-tert-butoxyphenyl)sulfonium p-toluenesulfonate, trinaphthylsulfonium trifluoromethanesulfonate, cyclohexylmethyl trifluoromethanesulfonate (2
-oxocyclohexyl)sulfonium, (2-norbornyl)methyl(2-oxocyclohexyl)sulfonium trifluoromethanesulfonate, onium salts such as 1,2′-naphthylcarbonylmethyltetrahydrothiophenium triflate; bis(benzenesulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(n-butylsulfonyl)diazomethane, bis(isobutylsulfonyl)diazomethane, bis(sec-butylsulfonyl)diazomethane,
Diazomethane derivatives such as bis(n-propylsulfonyl)diazomethane, bis(isopropylsulfonyl)diazomethane, bis(tert-butylsulfonyl)diazomethane; bis-(p-toluenesulfonyl)-α-dimethylglyoxime, bis-(n-butane) glyoxime derivatives such as sulfonyl)-α-dimethylglyoxime, bissulfone derivatives such as bisnaphthylsulfonylmethane; N-hydroxysuccinimide methanesulfonate, N-hydroxysuccinimide trifluoromethanesulfonate, N-hydroxysuccinimide 1-propanesulfonic acid ester, N-hydroxysuccinimide 2
- N such as propanesulfonate, N-hydroxysuccinimide 1-pentanesulfonate, N-hydroxysuccinimide p-toluenesulfonate, N-hydroxynaphthalimide methanesulfonate, and N-hydroxynaphthalimidebenzenesulfonate -Sulfonate derivatives of hydroxyimide compounds and the like are preferably used.

In the film-forming composition for lithography of the present embodiment, the content of the acid generator is not particularly limited, but is 0 to 50 parts by mass when the oxazine compound in the film-forming material for lithography is 100 parts by mass. is preferably 0 to 40 parts by mass.
By setting it within the preferred range described above, the cross-linking reaction tends to be enhanced, and the occurrence of the mixing phenomenon with the resist layer tends to be suppressed.

<Basic compound>
Furthermore, the composition for forming an underlayer film for lithography of the present embodiment may contain a basic compound from the viewpoint of improving storage stability.

The basic compound serves as a quencher for the acid to prevent the progress of the cross-linking reaction of the acid generated in a small amount by the acid generator. Such basic compounds include, but are not limited to, primary, secondary or tertiary aliphatic amines, mixed amines, aromatic group amines, heterocyclic amines, nitrogen-containing compounds having a carboxy group, nitrogen-containing compounds having a sulfonyl group, nitrogen-containing compounds having a hydroxyl group, nitrogen-containing compounds having a hydroxyphenyl group, alcoholic nitrogen-containing compounds, amide derivatives or and imide derivatives.

In the film-forming composition for lithography of the present embodiment, the content of the basic compound is not particularly limited. is preferably 0 to 1 part by mass.
When the content is within the preferred range described above, the storage stability tends to be enhanced without excessively impairing the cross-linking reaction.

Furthermore, the film-forming composition for lithography of the present embodiment may contain known additives. Examples of known additives include, but are not limited to, ultraviolet absorbers, antifoaming agents, colorants, pigments, nonionic surfactants, anionic surfactants, cationic surfactants, and the like.

[Underlayer film for lithography and pattern forming method]
The underlayer film for lithography of this embodiment is formed using the film-forming composition for lithography of this embodiment.

Further, the pattern forming method of the present embodiment includes the step (A-1) of forming an underlayer film on a substrate using the film-forming composition for lithography of the present embodiment, and forming at least one a step (A-2) of forming a photoresist layer of a layer, and a step (A-3) of, after the step (A-2), irradiating a predetermined region of the photoresist layer with radiation and developing the , has

Furthermore, another pattern forming method of the present embodiment includes the step (B-1) of forming an underlayer film on a substrate using the film-forming composition for lithography of the present embodiment; Step (B-2) of forming an intermediate layer film using a resist intermediate layer film material containing silicon atoms; and Step (B-3) of forming at least one photoresist layer on the intermediate layer film. and, after the step (B-3), a step (B-4) of irradiating a predetermined region of the photoresist layer with radiation and developing to form a resist pattern; Thereafter, the intermediate layer film is etched using the resist pattern as a mask, the lower layer film is etched using the obtained intermediate layer film pattern as an etching mask, and the substrate is etched using the obtained lower layer film pattern as an etching mask. and a step (B-5) of forming a pattern on the substrate.

As long as the underlayer film for lithography of this embodiment is formed from the film-forming composition for lithography of this embodiment, the formation method is not particularly limited, and known techniques can be applied. For example, after the film-forming composition for lithography of the present embodiment is applied onto a substrate by a known coating method such as spin coating or screen printing or a printing method, the organic solvent is removed by, for example, volatilization. An underlayer film can be formed.

When forming the lower layer film, it is preferable to perform baking in order to suppress the occurrence of the mixing phenomenon with the upper layer resist and promote the cross-linking reaction. In this case, the baking temperature is not particularly limited, but is preferably in the range of 80 to 450° C., more preferably 200° C.
~400°C. Also, the baking time is not particularly limited, but is preferably within the range of 10 to 300 seconds. The thickness of the underlayer film can be appropriately selected according to the required performance, and is not particularly limited. It is more preferably 50 to 1000 nm.

After forming the underlayer film on the substrate, a silicon-containing resist layer or a conventional hydrocarbon monolayer resist is formed thereon in the case of a two-layer process, and a silicon-containing intermediate layer is formed thereon in the case of a three-layer process, and further It is preferable to form a silicon-free monolayer resist layer thereon. In this case, a known photoresist material can be used for forming this resist layer.

As a silicon-containing resist material for a two-layer process, from the viewpoint of oxygen gas etching resistance, a silicon atom-containing polymer such as a polysilsesquioxane derivative or a vinylsilane derivative is used as a base polymer, and an organic solvent, an acid generator, A positive photoresist material containing a basic compound or the like, if necessary, is preferably used. Here, as the silicon atom-containing polymer, a known polymer used in this type of resist material can be used.

A polysilsesquioxane-based intermediate layer is preferably used as the silicon-containing intermediate layer for the three-layer process. Reflection tends to be effectively suppressed by providing the intermediate layer with an antireflection film effect. For example, in a 193 nm exposure process, if a material containing many aromatic groups and having high substrate etching resistance is used as the underlayer film, the k value tends to increase and the substrate reflection tends to increase. by reducing the substrate reflection to 0
. 5% or less. The intermediate layer having such an antireflection effect is not limited to the following, but for 193 nm exposure, an acid- or heat-crosslinking polysilsesquioxylate having a phenyl group or a silicon-silicon bond-containing light-absorbing group is introduced. Sun is preferably used.

An intermediate layer formed by a chemical vapor deposition (CVD) method can also be used. Although not limited to the following, for example, a SiON film is known as an intermediate layer that is highly effective as an antireflection film produced by a CVD method. Generally, C
Formation of the intermediate layer by a wet process such as spin coating or screen printing is simpler and more cost effective than the VD method. The upper layer resist in the three-layer process may be either positive type or negative type, and may be the same as a commonly used single layer resist.

Further, the underlayer film of the present embodiment can also be used as an antireflection film for a normal single-layer resist or as a base material for suppressing pattern collapse. Since the underlayer film of the present embodiment is excellent in etching resistance for underlayer processing, it can be expected to function as a hard mask for underlayer processing.

When the resist layer is formed from the photoresist material, a wet process such as spin coating or screen printing is preferably used as in the case of forming the underlayer film. After the resist material is applied by spin coating or the like, prebaking is usually performed, and it is preferable to perform this prebaking at 80 to 180° C. for 10 to 300 seconds. Then, according to a conventional method, exposure is performed, post-exposure bake (PEB),
A resist pattern can be obtained by developing. Although the thickness of the resist film is not particularly limited, it is generally preferably 30 to 500 nm, more preferably 50 to 4 nm.
00 nm.

Also, the exposure light may be appropriately selected and used according to the photoresist material to be used. Generally, high energy rays with a wavelength of 300 nm or less, specifically 248 nm, 193 nm,
Excimer lasers of 157 nm, soft X-rays of 3 to 20 nm, electron beams, X-rays and the like can be mentioned.

In the resist pattern formed by the above-described method, pattern collapse is suppressed by the underlayer film of the present embodiment. Therefore, by using the underlayer film of this embodiment, a finer pattern can be obtained, and the exposure dose required for obtaining the resist pattern can be reduced.

Next, etching is performed using the obtained resist pattern as a mask. Gas etching is preferably used for etching the lower layer film in the two-layer process. As the gas etching, etching using oxygen gas is suitable. In addition to oxygen gas, He, Ar
It is also possible to add inert gases such as CO, CO ₂ , NH ₃ , SO ₂ , N ₂ , NO _{2 and} H ₂ gases. CO, CO ₂ , NH ₃ , N ₂ , NO _{2 ,} H
Gas etching can also be performed with only _two gases. In particular, the latter gas is preferably used for sidewall protection to prevent undercutting of pattern sidewalls.

On the other hand, gas etching is also preferably used for etching the intermediate layer in the three-layer process. As the gas etching, the same one as described in the above two-layer process can be applied. In particular, it is preferable to process the intermediate layer in the three-layer process using a freon-based gas and using a resist pattern as a mask. After that, as described above, the intermediate layer pattern is used as a mask to perform, for example, oxygen gas etching, so that the lower layer film can be processed.

Here, when forming an inorganic hard mask intermediate layer film as the intermediate layer, CVD method or ALD method is used.
A silicon oxide film, a silicon nitride film, and a silicon oxynitride film (SiON film) are formed by a method or the like. The method for forming the nitride film is not limited to the following, but for example, the methods described in Japanese Patent Application Laid-Open No. 2002-334869 (Patent Document 6) and WO2004/066377 (Patent Document 7) can be used. Although a photoresist film can be formed directly on such an intermediate layer film, an organic anti-reflective coating (BARC) is formed on the intermediate layer film by spin coating, and a photoresist film is formed thereon. You may

As an intermediate layer, a polysilsesquioxane-based intermediate layer is also preferably used. Reflection tends to be effectively suppressed by giving the resist intermediate layer film an effect as an antireflection film. Specific materials for the polysilsesquioxane-based intermediate layer are not limited to the following, but are described in, for example, JP-A-2007-226170 (Patent Document 8) and JP-A-2007-226204 (Patent Document 9). can be used.

Subsequent etching of the substrate can also be performed by conventional methods, for example, if the substrate is SiO
_2. SiN can be etched mainly with Freon-based gas, and p-Si, Al, and W can be etched mainly with chlorine-based or bromine-based gas. When the substrate is etched with a flon-based gas, the silicon-containing resist in the two-layer resist process and the silicon-containing intermediate layer in the three-layer process are stripped off at the same time as the substrate is processed. On the other hand, when the substrate is etched with a chlorine-based or bromine-based gas, the silicon-containing resist layer or the silicon-containing intermediate layer is removed separately, and generally, after the substrate is processed, the dry-etching removal is performed with a flon-based gas. .

The underlayer film of the present embodiment is characterized by being excellent in etching resistance of these substrates. The substrate can be appropriately selected and used from known substrates, and is not particularly limited, but Si, α-S,
i, p-Si, SiO ₂ , SiN, SiON, W, TiN, Al and the like. again,
The substrate may be a laminate having a film to be processed (substrate to be processed) on a base material (support). Such films to be processed include Si, SiO ₂ , SiON, SiN, p-Si, α-Si,
Various Low-k films such as W, W--Si, Al, Cu, and Al--Si, and their stopper films, etc., are exemplified, and a material different from that of the substrate (support) is usually used. The thickness of the substrate to be processed or the film to be processed is not particularly limited, but is usually 50 to 1,000,000.
It is preferably about 0 nm, more preferably 75 to 500,000 nm.

EXAMPLES The present invention will be described in more detail below with reference to examples, production examples, and comparative examples, but the present invention is not limited to these examples.

[Molecular weight]
The molecular weight of the synthesized compound was measured by Acquity UPLC/MALDI-
Measured by LC-MS analysis using Synapt HDMS.

[Evaluation of heat resistance]
Using an EXSTAR6000TG-DTA device manufactured by SII Nanotechnology Co., Ltd., about 5 mg of a sample is placed in a non-sealed aluminum container and heated to 500 ° C. at a heating rate of 10 ° C./min in a nitrogen gas (100 ml / min) stream. The amount of heat weight loss was measured by this method. From a practical viewpoint, the following A or B evaluation is preferable. If it is evaluated as A or B, it has high heat resistance and can be applied to high temperature baking.
<Evaluation Criteria>
A: Thermal weight loss at 400°C is less than 10% B: Thermal weight loss at 400°C is 10% to 25%
C: Thermal weight loss at 400 ° C. is more than 25%

[Evaluation of solubility]
Propylene glycol monomethyl ether acetate (PG
MEA) and compound and/or resin were charged, and after stirring with a magnetic stirrer at 23° C. for 1 hour, the amount of compound and/or resin dissolved in PGMEA was measured, and the results were evaluated according to the following criteria. From a practical point of view, the following A or B evaluation is preferable. If it is evaluated as A or B, it has high storage stability in a solution state and is sufficiently applicable to edge beat rinse liquid (PGME/PGMEA mixed liquid) widely used in semiconductor microfabrication processes.
<Evaluation Criteria>
A: 10% by mass or more B: 5% by mass or more and less than 10% by mass C: less than 5% by mass

熱重量測定の結果、得られたリソグラフィー用膜形成材料の４００℃での熱重量減少量
は１０％未満（評価Ａ）であった。また、ＰＧＭＥＡへの溶解性を評価した結果、１０質
量％以上（評価Ａ）であり、得られたリソグラフィー用膜形成材料は優れた溶解性を有す
るものと評価された。
前記リソグラフィー用膜形成材料中のビスマレイミド化合物と付加重合型マレイミド樹
脂との合計質量１０質量部に対し、溶媒としてＰＧＭＥＡを９０質量部加え、室温下、ス
ターラーで少なくとも３時間以上攪拌させることにより、リソグラフィー用膜形成用組成
物を調製した。 <Example 1>
5 parts by mass of BMI-70 was used as the bismaleimide compound, and 5 parts by mass of BMI-2300 was used as the addition polymerization type maleimide resin. In addition, 2 parts by mass of benzoxazine (BF-BXZ; manufactured by Konishi Chemical Industry Co., Ltd.) represented by the following formula was used, and 2,4
, 5-triphenylimidazole (TPIZ) was blended to prepare a film-forming material for lithography.

As a result of thermogravimetric measurement, the amount of thermal weight loss at 400° C. of the obtained film-forming material for lithography was less than 10% (evaluation A). Further, the solubility in PGMEA was evaluated to be 10% by mass or more (evaluation A), and the obtained film-forming material for lithography was evaluated to have excellent solubility.
90 parts by mass of PGMEA as a solvent is added to 10 parts by mass of the total mass of the bismaleimide compound and the addition polymerizable maleimide resin in the film-forming material for lithography, and the mixture is stirred at room temperature with a stirrer for at least 3 hours to obtain A film-forming composition for lithography was prepared.

熱重量測定の結果、得られたリソグラフィー用膜形成材料の４００℃での熱重量減少量
は１０％未満（評価Ａ）であった。また、ＰＧＭＥＡへの溶解性を評価した結果、１０質
量％以上（評価Ａ）であり、得られたリソグラフィー用膜形成材料は優れた溶解性を有す
るものと評価された。
前記ビスマレイミド化合物１０質量部に対し、溶媒としてＰＧＭＥＡを９０質量部加え
、室温下、スターラーで少なくとも３時間以上攪拌させることにより、リソグラフィー用
膜形成用組成物を調製した。 <Example 2>
As the bismaleimide compound, 10 parts by mass of BMI-1000P and 2 parts by mass of the benzoxazine BF-BXZ represented by the above formula were used, and 0.0 part of TPIZ was used as the cross-linking accelerator.
1 part by mass was blended to obtain a film-forming material for lithography.

As a result of thermogravimetric measurement, the amount of thermal weight loss at 400° C. of the obtained film-forming material for lithography was less than 10% (Evaluation A). Further, the solubility in PGMEA was evaluated to be 10% by mass or more (evaluation A), and the obtained film-forming material for lithography was evaluated to have excellent solubility.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound, and the mixture was stirred at room temperature with a stirrer for at least 3 hours to prepare a film-forming composition for lithography.

熱重量測定の結果、得られたリソグラフィー用膜形成材料の４００℃での熱重量減少量
は１０％未満（評価Ａ）であった。また、ＰＧＭＥＡへの溶解性を評価した結果、１０質
量％以上（評価Ａ）であり、得られたリソグラフィー用膜形成材料は優れた溶解性を有す
るものと評価された。
前記ビスマレイミド化合物１０質量部に対し、溶媒としてＰＧＭＥＡを９０質量部加え
、室温下、スターラーで少なくとも３時間以上攪拌させることにより、リソグラフィー用
膜形成用組成物を調製した。 <Example 3>
As the bismaleimide compound, 10 parts by mass of BMI-80 and 2 parts by mass of the benzoxazine BF-BXZ represented by the above formula are used, and 0.1 part by mass of TPIZ is blended as a cross-linking accelerator to form a film for lithography. used as a forming material.

As a result of thermogravimetric measurement, the amount of thermal weight loss at 400° C. of the obtained film-forming material for lithography was less than 10% (evaluation A). Further, the solubility in PGMEA was evaluated to be 10% by mass or more (evaluation A), and the obtained film-forming material for lithography was evaluated to have excellent solubility.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound, and the mixture was stirred at room temperature with a stirrer for at least 3 hours to prepare a film-forming composition for lithography.

<Example 4>
As an oxazine compound, 10 parts by mass of benzoxazine BF-BXZ alone was used as a film-forming material for lithography.
As a result of thermogravimetric measurement, the amount of thermal weight loss at 400° C. of the obtained film-forming material for lithography was less than 10% (Evaluation A). Further, the solubility in PGMEA was evaluated to be 10% by mass or more (evaluation A), and the obtained film-forming material for lithography was evaluated to have the necessary solubility.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the film-forming material for lithography, and the mixture was stirred at room temperature with a stirrer for at least 3 hours to prepare a film-forming composition for lithography.

<Example 5>
10 parts by mass of BMI-70 was used as the bismaleimide compound. Further, using 2 parts by mass of benzoxazine BF-BXZ, as a photoradical polymerization initiator, Irgacure 18
4 (manufactured by BASF) was added in an amount of 0.1 part by mass to prepare a film-forming material for lithography.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound in the film-forming material for lithography, and the mixture was stirred at room temperature with a stirrer for at least 3 hours to prepare a film-forming composition for lithography. .

前記ビスマレイミド化合物１０質量部に対し、溶媒としてＰＧＭＥＡを９０質量部加え
、室温下、スターラーで少なくとも３時間以上攪拌させることにより、リソグラフィー用
膜形成用組成物を調製した。 <Example 6>
10 parts by mass of BMI-50P was used as the bismaleimide compound. In addition, using 2 parts by mass of benzoxazine BF-BXZ, as a photoradical polymerization initiator, Irgacure 1
0.1 part by mass of 84 (manufactured by BASF) was blended to prepare a film-forming material for lithography.

90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound, and the mixture was stirred with a stirrer at room temperature for at least 3 hours to prepare a film-forming composition for lithography.

<Example 7>
10 parts by mass of BMI-1000P was used as the bismaleimide compound. Also, 2 parts by mass of benzoxazine BF-BXZ was used, and 0.1 part by mass of Irgacure 184 (manufactured by BASF) was added as a photoradical polymerization initiator to obtain a film-forming material for lithography.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound, and the mixture was stirred with a stirrer at room temperature for at least 3 hours to prepare a film-forming composition for lithography.

<Example 8>
10 parts by mass of BMI-80 was used as the bismaleimide compound. Further, using 2 parts by mass of benzoxazine BF-BXZ, as a photoradical polymerization initiator, Irgacure 18
4 (manufactured by BASF) was added in an amount of 0.1 part by mass to prepare a film-forming material for lithography.
90 parts by mass of PGMEA as a solvent was added to 10 parts by mass of the bismaleimide compound, and the mixture was stirred with a stirrer at room temperature for at least 3 hours to prepare a film-forming composition for lithography.

<Production Example 1>
A 10 L four-necked flask capable of bottom extraction was prepared, equipped with a Dimroth condenser, a thermometer and a stirring blade. Into this four-necked flask, 1.09 kg (7 mol, manufactured by Mitsubishi Gas Chemical Co., Ltd.) of 1,5-dimethylnaphthalene and 2.1 parts of a 40% by mass formalin aqueous solution were placed in a nitrogen stream.
kg (28 mol as formaldehyde, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 0.97 ml of 98% by mass sulfuric acid (manufactured by Kanto Chemical Co., Ltd.) were charged and reacted under normal pressure at 100° C. for 7 hours while refluxing. After that, 1.8 kg of ethylbenzene (manufactured by Wako Pure Chemical Industries, Ltd., reagent special grade) was added as a diluting solvent to the reaction solution, and after standing, the lower aqueous phase was removed. Furthermore, neutralization and washing with water were carried out, and ethylbenzene and unreacted 1,5-dimethylnaphthalene were distilled off under reduced pressure to obtain 1.25 kg of light brown solid dimethylnaphthalene formaldehyde resin.
The molecular weight of the obtained dimethylnaphthalene formaldehyde resin is the number average molecular weight (Mn)
: 562, weight average molecular weight (Mw): 1168, and dispersity (Mw/Mn): 2.08.

Subsequently, a four-necked flask with an internal volume of 0.5 L equipped with a Dimroth condenser, a thermometer and a stirring blade was prepared. In this four-necked flask, 100 g (0.51 mol) of the dimethylnaphthalene formaldehyde resin obtained as described above and 0.05 g of p-toluenesulfonic acid were charged under a nitrogen stream, and the temperature was raised to 190 ° C. After heating for 1 hour, it was stirred. After that, 52.0 g (0.36 mol) of 1-naphthol was further added, and the temperature was raised to 220° C. and reacted for 2 hours. After dilution with the solvent, neutralization and washing were carried out, and the solvent was removed under reduced pressure to obtain 126.1 g of modified resin (CR-1) as a dark brown solid.
The resulting resin (CR-1) has Mn: 885, Mw: 2220, Mw/Mn: 2.51
Met.
As a result of thermogravimetry (TG), the amount of thermal weight loss of the obtained resin at 400° C. was over 25% (evaluation C). Therefore, it was evaluated as being difficult to apply to high-temperature baking.
As a result of evaluating the solubility in PGMEA, it was 10% by mass or more (evaluation A), and was evaluated as having excellent solubility.
The above Mn, Mw and Mw/Mn were measured by performing gel permeation chromatography (GPC) analysis under the following conditions and obtaining molecular weights in terms of polystyrene.
Apparatus: Shodex GPC-101 type (manufactured by Showa Denko Co., Ltd.)
Column: KF-80M x 3
Eluent: THF 1 mL/min
Temperature: 40°C

次いで、実施例１～４、比較例１～２のリソグラフィー用膜形成用組成物をシリコン基
板上に回転塗布し、その後、２４０℃で６０秒間、さらに４００℃で１２０秒間ベークし
て、膜厚２００ｎｍの下層膜を各々作製した。前記４００℃でベーク前後の膜厚差から膜
厚減少率（％）を算出して、各下層膜の膜耐熱性を評価した。そして、下記に示す条件に
てエッチング耐性を評価した。
また、下記に示す条件にて、段差基板への埋め込み性、及び平坦性を評価した。 <Examples 1 to 4, Comparative Examples 1 to 2>
Lithographic film-forming compositions were prepared as in Examples 1-4. Moreover, Production Example 1
Using the resin obtained in 1., lithography film-forming compositions of Comparative Examples 1 and 2 were prepared.
The composition of each composition is as shown in Table 1. The phenylaralkyl type epoxy resin (NC-3000-L; manufactured by Nippon Kayaku Co., Ltd.) as a cross-linking agent is represented by the following formula.

Then, the film-forming compositions for lithography of Examples 1 to 4 and Comparative Examples 1 and 2 were spin-coated on a silicon substrate, and then baked at 240° C. for 60 seconds and further at 400° C. for 120 seconds to obtain a film thickness. A 200 nm underlayer film was prepared for each. The thickness reduction rate (%) was calculated from the thickness difference before and after baking at 400° C., and the film heat resistance of each lower layer film was evaluated. Then, the etching resistance was evaluated under the conditions shown below.
In addition, the embeddability into the stepped substrate and the flatness were evaluated under the following conditions.

<Examples 5 to 8>
Lithographic film-forming compositions were prepared as in Examples 5-8. The composition of each composition is as shown in Table 2. Next, the film-forming compositions for lithography of Examples 5 to 8 were spin-coated on a silicon substrate, then baked at 110° C. for 60 seconds to remove the solvent from the coating film, and then subjected to integrated exposure with a high-pressure mercury lamp. It was cured with an amount of 600 mJ/cm ² and an irradiation time of 20 seconds, and further baked at 400° C. for 120 seconds to prepare each underlayer film with a thickness of 200 nm. The thickness reduction rate (%) was calculated from the thickness difference before and after baking at 400° C., and the film heat resistance of each lower layer film was evaluated. Then, the etching resistance was evaluated under the conditions shown below.
In addition, the embeddability into the stepped substrate and the flatness were evaluated under the following conditions.

[Evaluation of film heat resistance]
<Evaluation Criteria>
S: Film thickness reduction rate before and after baking at 400°C ≤ 10%
A: Film thickness reduction rate before and after baking at 400°C ≤ 15%
B: Film thickness reduction rate before and after baking at 400°C ≤ 20%
C: film thickness reduction rate before and after baking at 400° C.>20%

[Etching test]
Etching device: RIE-10NR manufactured by Samco International
Output: 50W
Pressure: 4Pa
Time: 2min
Etching gas CF4 gas flow rate: _O2 gas flow rate = 5:15 ₍ sccm)

[Evaluation of etching resistance]
Etching resistance was evaluated by the following procedure.
First, under the same conditions as in Example 1, except that novolak (PSM4357 manufactured by Gun Ei Kagaku Co., Ltd.) was used instead of the film-forming material for lithography in Example 1, and the drying temperature was set to 110° C., a novolac underlayer film was formed. was made. Then, for this novolac underlayer film,
The etching test described above was performed, and the etching rate at that time was measured.
Next, the etching test was performed in the same manner for the underlayer films of Examples 1 to 8 and Comparative Examples 1 and 2, and the etching rate at that time was measured.
Using the etching rate of the novolac underlayer film as a reference, the etching resistance was evaluated according to the following evaluation criteria. From a practical point of view, the following S evaluation is particularly preferable, and A and B evaluations are preferable.
<Evaluation Criteria>
S: Etching rate less than -30% compared to novolac underlayer film A: Etching rate less than -30% to -20% compared to novolak underlayer film B: Etching rate compared to novolak underlayer film but -20% or more to less than -10% C: The etching rate is -10% or more and 0% or less compared to the novolak underlayer film

[Evaluation of embeddability in stepped substrate]
Evaluation of the embeddability into the stepped substrate was performed by the following procedure.
The composition for forming an underlayer film for lithography was coated on a 60nm line-and-space SiO ₂ substrate having a film thickness of 80nm, and baked at 240°C for 60 seconds to form a 90nm underlayer film. A cross section of the obtained film was cut out and observed with an electron microscope to evaluate embeddability into the stepped substrate.
<Evaluation Criteria>
A: The underlayer film is embedded without defects in the uneven portions of the 60 nm line-and-space SiO ₂ substrate.
C: The uneven part of the 60 nm line and space _SiO2 substrate has defects and is not filled with the underlying film.

[Flatness evaluation]
Trench width 100 nm, pitch 150 nm, depth 150 nm (aspect ratio: 1.5
) and a trench (open space) with a width of ₅ μm and a depth of 180 nm. After that, it was baked at 240° C. for 120 seconds in an air atmosphere to form a resist underlayer film having a thickness of 200 nm. The shape of this resist underlayer film was observed with a scanning electron microscope ("S-4800" by Hitachi High-Technologies Corporation).
”), and the difference (ΔFT) between the maximum and minimum film thicknesses of the resist underlayer film on the trench or space was measured.
<Evaluation Criteria>
S: ΔFT<10 nm (best flatness)
A: 10 nm ≤ ΔFT < 20 nm (good flatness)
B: 20 nm ≤ ΔFT < 40 nm (slightly good flatness)
C: 40 nm ≤ ΔFT (poor flatness)

<Example 9>
By applying the film-forming composition for lithography in Example 1 onto a _SiO2 substrate having a film thickness of 300 nm and baking it at 240° C. for 60 seconds and further at 400° C. for 120 seconds,
A lower layer film having a film thickness of 70 nm was formed. A resist solution for ArF is applied on this underlayer film, and 1
A photoresist layer having a film thickness of 140 nm was formed by baking at 30° C. for 60 seconds. As the ArF resist solution, a compound of the following formula (22): 5 parts by mass, triphenylsulfonium nonafluoromethanesulfonate: 1 part by mass, tributylamine: 2 parts by mass,
and PGMEA: 92 parts by mass were used.
In addition, the compound of the following formula (22) was prepared as follows. That is, 2-methyl-2-
4.15 g of methacryloyloxyadamantane, 3.00 g of methacryloyloxy-γ-butyrolactone, 2.08 g of 3-hydroxy-1-adamantyl methacrylate, and 0.38 g of azobisisobutyronitrile were dissolved in 80 mL of tetrahydrofuran to form a reaction solution. bottom. This reaction solution was polymerized for 22 hours while maintaining the reaction temperature at 63° C. under a nitrogen atmosphere, and then added dropwise to 400 mL of n-hexane. The produced resin thus obtained was coagulated and purified, and the produced white powder was filtered and dried under reduced pressure at 40° C. overnight to obtain a compound represented by the following formula.

In the formula (22), 40, 40, and 20 indicate the ratio of each structural unit,
It does not indicate a block copolymer.

Then, using an electron beam lithography system (Elionix; ELS-7500, 50 keV), the photoresist layer is exposed, baked (PEB) at 115 ° C. for 90 seconds, and 2.38% by mass of tetramethylammonium hydroxide ( A positive resist pattern was obtained by developing with an aqueous TMAH) solution for 60 seconds. Table 3 shows the evaluation results.

<Example 10>
A positive resist pattern was obtained in the same manner as in Example 9, except that the composition for forming an underlayer film for lithography in Example 2 was used instead of the composition for forming an underlayer film for lithography in Example 1. . Table 3 shows the evaluation results.

<Example 11>
A positive resist pattern was obtained in the same manner as in Example 9, except that the composition for forming an underlayer film for lithography in Example 3 was used instead of the composition for forming an underlayer film for lithography in Example 1. . Table 3 shows the evaluation results.

<Example 12>
A positive resist pattern was obtained in the same manner as in Example 9, except that the composition for forming an underlayer film for lithography in Example 4 was used instead of the composition for forming an underlayer film for lithography in Example 1. . Table 3 shows the evaluation results.

<Comparative Example 3>
The photoresist layer was formed of Si in the same manner as in Example 9, except that the lower layer film was not formed.
It was formed directly on an _O2 substrate to obtain a positive resist pattern. Table 3 shows the evaluation results.

[evaluation]
55 nmL/S (1:1
) and 80 nm L/S (1:1) resist patterns were observed using an electron microscope (S-4800, manufactured by Hitachi, Ltd.). With respect to the shape of the resist pattern after development, a resist pattern with good rectangularity without pattern collapse was evaluated as good, and a non-perfect resist pattern was evaluated as unsatisfactory. Further, as a result of the observation, the minimum line width with good rectangularity without pattern collapse was used as an index for evaluation as resolution. Further, the sensitivity was defined as the minimum energy amount of electron beams capable of drawing a good pattern shape, and this was used as an index for evaluation.

As is clear from Table 3, Examples 9 to 12 using the film-forming composition for lithography of the present embodiment containing a benzoxazine compound significantly improved both resolution and sensitivity compared to Comparative Example 3. confirmed to be excellent. Moreover, it was confirmed that the shape of the resist pattern after development had no pattern collapse and had good rectangularity. Furthermore, from the difference in resist pattern shape after development, Example 9 obtained from the lithography film-forming composition of Examples 1 to 4
It was shown that the underlayer films of ˜12 have good adhesion to the resist material.

The film-forming material for lithography of the present embodiment has relatively high heat resistance, relatively high solvent solubility, excellent embedding characteristics in stepped substrates and excellent film flatness, and is applicable to wet processes. Therefore, a lithographic film-forming composition containing a lithographic film-forming material can be widely and effectively used in various applications requiring these properties. In particular, the present invention can be effectively used in the fields of underlayer films for lithography and underlayer films for multi-layer resists.

Claims (15)

A film-forming material for lithography containing an oxazine compound. 3. The lithographic film-forming according to claim 1, wherein the oxazine compound comprises a condensed ring of a six-membered ring containing one oxygen atom, one nitrogen atom and four carbon atoms as ring member atoms and an aromatic ring. material. 3. The film-forming material for lithography according to claim 2, wherein the oxazine compound is at least one compound selected from the group consisting of compounds represented by formulas (a) to (f) below.

[In the formula,
R ¹ and R ² are independently an organic group having 1 to 30 carbon atoms,
R ³ to R ⁶ are independently hydrogen or a hydrocarbon group having 1 to 6 carbon atoms,
X is a single bond, -O-, -S-, -S-S-, -SO ₂ -, -CO-, -CONH-,
—NHCO—, —C(CH ₃ ) ₂ —, —C(CF ₃ ) ₂ —, —(CH ₂ ) _m —, —O—(CH ₂
) _m —O—, or —S—(CH ₂ ) _m —S—;
m is an integer from 1 to 6,
Y is independently a single bond, -O-, -S-, -CO-, -C(CH ₃ ) ₂ -, -C(CF
₃ ) _2- or alkylene having 1 to 3 carbon atoms]. A group of the following formula (0):

(In formula (0), each R is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms)
4. The film-forming material for lithography according to claim 1, further comprising a compound having The film-forming material for lithography according to any one of claims 1 to 4, further comprising a cross-linking agent. 5. The cross-linking agent is at least one selected from the group consisting of phenol compounds, epoxy compounds, cyanate compounds, amino compounds, melamine compounds, guanamine compounds, glycoluril compounds, urea compounds, isocyanate compounds and azide compounds. 3. The film-forming material for lithography according to . The film-forming material for lithography according to any one of claims 1 to 6, further comprising a cross-linking accelerator. 8. The film-forming material for lithography according to claim 1, further comprising a radical polymerization initiator. A film-forming composition for lithography, comprising the film-forming material for lithography according to any one of claims 1 to 8 and a solvent. 10. The film-forming composition for lithography according to claim 9, further comprising an acid generator. 11. The composition for forming a lithographic film according to claim 10, wherein the lithographic film is an underlayer film for lithography. An underlayer film for lithography formed using the film-forming composition for lithography according to claim 11 . forming an underlayer film on a substrate using the film-forming composition for lithography according to claim 11;
a step of forming at least one layer of photoresist layer on the underlayer film; and a step of irradiating a predetermined region of the photoresist layer with radiation and developing;
A method of forming a resist pattern, comprising: forming an underlayer film on a substrate using the film-forming composition for lithography according to claim 11;
forming an intermediate layer film on the underlayer film using a resist intermediate layer film material containing silicon atoms;
forming at least one photoresist layer on the intermediate layer film;
a step of irradiating a predetermined region of the photoresist layer with radiation and developing to form a resist pattern;
etching the intermediate layer film using the resist pattern as a mask;
Etching the underlayer film using the obtained intermediate layer film pattern as an etching mask; and Etching the substrate using the obtained underlayer film pattern as an etching mask to form a pattern on the substrate;
A method of forming a circuit pattern, comprising: a step of dissolving the film-forming material for lithography according to any one of claims 1 to 8 in a solvent to obtain an organic phase;
a first extraction step of contacting the organic phase with an acidic aqueous solution to extract impurities in the film-forming material for lithography;
including
A purification method, wherein the solvent used in the step of obtaining the organic phase comprises a solvent optionally immiscible with water.